My shop is in an over-sized two-car garage attached to my home. My work is a calling, in the theological sense of the word. Ethical and moral questions arise every day – they are hard, sharp, unambiguous and unavoidable.

Float Needles and Blown Fuses

Posted: August 30th, 2013 | Author: Administrator | Filed under: Fuel & Air, Ignition, Timing, & Electrical, Motorcycle Repair | Tags: , | No Comments »

It doesn’t take much at all to cause a float needle to improperly seat and allow fuel to keep flowing. The smallest bit of debris can keep the needle from seating properly and cutting off the fuel flow. Below is an email exchange with a customer regarding such float problems. Also, there are some useful tidbits about diagnosing electrical problems. Enjoy!

Hi Chris, we talked , in past, over phone…I managed to get all plugs in the 83 Venture @ .035 with new OEM(paper element) air filter….I am getting a backfire on deceleration on one cylinder, and idle is just not a consistant solid RPM…vaies, maybe 300 RPM’s at idle…..In your expert opinion, is this a valve adjustment problem and/or carb out of sync? Or, is air filter not breathing as free as it should? Have a great and safe 4th weekend…this is an irratating issue…I drove down to Pickens today and the bike runs smooth enough on the highway….then decelerate and pop goes the weasel….many thanks……need to bring it to an expert….
Respectfully,
W


W,

The symptoms you describe are typical of a cylinder running lean at low rpms. This can be caused by either a carb with clogged up idle/pilot jets or by an air leak. If you can tell which cyl. is the culprit, removal and a thorough cleaning should do the trick. The other possibility is that the rubber intake manifold between the carb and the intake port is cracked and leaking air. Less likely but possible is that the little rubber o-ring sealing the pilot air screw is leaking.

Cheers,
Chris


Hi Chris, I left you a ph message, but here are the symptoms…..1983 Yamaha Venture…one carb is dumping gas and it goes down to ground through short hose….It runs smooth, and strong, but I am wanting to take a trip north (487 mi) to 85 miles SW of Indianapolis camping in KY on way there and back….you can see the gas flow in the carb in question(when air filter is removed), but not other 3 carbs are showing gas flow…Do you think, by adding Sea Foam, to gas line, recently, I could have screwed up the works? Also, I overfilled the tank last saturday, then didn’t drive until yesterday, and noticed gas smell but really had to hunt down leak…..possible vapor lock from heat and expansion yesterday? Anyway, I need to get this fixed….
Many Thanks, Respectfully,
W


Wayne,

My guess is that the problem is that the Sea Foam did its job and dislodged accumulated crud – one little speck of which had lodged in the float needle seat and is preventing it from shutting off the fuel flow to that carb. The overfilling is probably just a coincidence.

An important caveat: I have not worked on a Venture before but a friend of mine has one and there is a lot of stuff to remove before one can put that carb on the bench to work on it. If you have a good shop manual – great – if not, I will need to purchase one – about $30 for a Clymer or Haynes. I can figure out just about anything – given time – and I adjust my hours to reflect what I think it should have taken someone familiar with the bike. But you may prefer to take it to a Yamaha dealer or another mechanic who has experience with this bike. I think, if I were in your shoes, that’s what I would do.

Let me know what you decide.

Cheers,
Chris


Chris,
I traced another caveat: my headlight went out…I took the HL housing apart and cleaned connectors……put it together…still no light….went to fuse box and the head lamp, 10 amp fuse, had burned a hole in plastic fuse housing…I Jerry rigged one annode side of glass fuse with a fashioned connector (what I had available to improvise) and snapped the good side back in…works, but no high beam, so I believe I need a new lamp and a permanent fix for the fuse box defiency…I like working on bikes, but my expertise is limited…Been riding for 42 yrs, and, at 60, still learning new tricks…..my tool kit is my own variety of tools, including cold touch soldering iron, flares, flashlight, night light sticks, electrical & duct tape, fuses, extra plugs, plug gapper, tool to get plugs out and in, Teflon tie sticks, first aid kit, rainsuit, 3 sets of gloves including gaunlet, and misc items for most common fixes…I have running lights, mini-red strobe lights which are motion activated, deer horn alerts(I know they work lol), highway pegs, and a small instrument cluster containing, clock, compass, and thermometer…..these add-ons are for better visability & safety and function…..bike is stock…no mods….Have a great weekend……
Respectfully,
W


Wayne,

The blown fuse means that something in that circuit is drawing more than 10 amps – typically due to either a short or a bad ground. The most likely culprit is inside the light switch module on the handlebar. Less likely is that the headlight itself shorted internally. The fuse exists to protect the electrical components – and from the bike going up in flames – worst case. Juryrigging/bypassing the fuse will – sooner or later – result in much more expensive problems than you have now. If you have a multi-meter you should be able to located the fault and correct it.

Good luck in getting it sorted out.

Cheers,
Chris


What Can a Spark Plug Tell You?

Posted: August 30th, 2013 | Author: Administrator | Filed under: Engine, Fuel & Air, Motorcycle Repair | No Comments »

Knowing how to read a spark plug can give you very helpful insight into what is actually happening inside of your engine. Below is a correspondence I had with a customer explaining what I could deduce from the state of his plugs.

R,

I did a quick and dirty compression test on the cold engine – 140 psi on the left cyl and 150 on the right. These values will increase to around 160 psi when measured correctly on a hot engine – and that’s very good. So your engine is fundamentally sound and I can procede with the work.

Significantly, the two spark plugs looked very different and yeild clues as to the poor performance. The insulator tip can be read to give a good idea of what’s happening in the combustion chamber. The left plug was black with an oily sheen while the right was nearly white and dry. I suspect that one of the valve guide seals on the left cyl is allowing oil from the cams down the valve stem into the cyl and that the right cyl is running way too lean. I’ll take another plug reading after I have cleaned/rebuilt/adjusted the carbs. If the oil fouling on the left cyl is not too bad, it may be better/cheaper to just replace that plug once in a while rather than pull the head to install new seals. Plugs are cheap and easy to replace. Valve guide seals are not.

Cheers,
Chris


The Wretched Truth About Restorations

Posted: December 13th, 2012 | Author: Administrator | Filed under: Editorial, Engine, Forks & Steering, Frame & Body, Fuel & Air, Ignition, Timing, & Electrical, Motorcycle Repair, Wheels, Tires, & Brakes | Tags: , | 7 Comments »

Greetings Chris,

I have researched available motorcycle restoration shops on the East Coast and have found your shop one of the best suited for my project. I would like to determine if your willing and able to restore a vintage Yamaha 80 enduro shown in the pictures attached? If so, to what level of restoration are you capable of achieving? And how long would this take? Further, what ballpark pricing can you provide?

Regards,
R

_____________________

R,

Thanks for your note of inquiry – and the very flattering words about my shop and work.

First, I need to know that you know the First Law of Restorations; you will end up spending waaaaay more than the finished product will fetch on the open market – two to three times more is the rule of thumb – and the multiple is higher with smaller displacement bikes.

So let’s see if I can scare you off right now. Mechanical restoration/rebuilding will run $3k – half parts and half my time. Cosmetic restoration will be another $3k – about half for first-rate factory correct paint and decals and half for re-chroming which, when properly done, means stripping the old chrome from the part, filling the deeper rust pits and other defects with a conductive metal filler, a heavy layer of copper plate to fill the smaller pits, a layer of nickle to keep the copper from showing through the final layer of chrome. This process is sometimes called “triple chrome.” Better add another $1k to cover things like tires, seat re-upholstery, and this, that, and the other thing. That’s $7k – and no matter how realistically I think I am estimating time and money, everything takes longer and costs more than I had expected – even when I know this and take it into account. That may be the Second Law of Restorations; everything will take longer and cost more than even your worst-case estimate. A final bill of $8k could happen. And all this for a bike that will be worth no more than $3k when done – probably closer to $2k.

I have been doing this stuff long enough to have learned a few things; nobody ever complains about getting a bill less than they expected. Dealing with a panicky customer as the running estimate is regularly revised upward is no fun. I’d rather scare you to death right now.

I’ve just come in from the shop – 11pm – after an afternoon favor checking out a problem on my sweetie’s son’s bike turned into eight hours of pro-bono work – time for a bit of supper.

Cheers,
Chris
Existential Motorcycles TEL: 828-6839289 Web: http://www.existentialmotorcycles.com
Alexander, NC 28701

______________________

Greetings Chris,

Thanks for your carefully thought out email below. Your thoughts and details provided are worth close observation and consideration. With the economy in its current state and no prospects for any improvement in the foreseable years ahead, I must fully think through what makes sense for me moving forward. I will let you know if I decide to proceed in the coming months.

Happy Holidays and warm regards,
R

________________

R,

Thanks for taking my bucket of cold water over your head so well.

Now I can ethically add that there are many excellent non-monetary reasons/rewards for/from restoring a bike – all better reasons, in my way of reckoning, than money.

And it could be done in two stages; mechanics/functional restoration one year and the pretty bits the next.

But it will be expensive and time-consuming.

Under no circumstances should you compromise your financial health to take on a proper restoration. It sucks all the fun out of it – and the damned bike becomes the cause of it all. And I become the dealer man for whom you are stealing the children’s lunch money to feed your habit. Pure poison. If/when you do this, have the cash on hand and set aside.

I do take extensive notes as I work and lots of digi-pix. On long-term projects I send these as updates every day or so – kinda helps the customer come along for the ride – and adds considerable value to the results – builder’s notes and documentary pix impress the hell out of buyers. But most of all, it’s fun for everybody. I enjoy telling stories of the day’s work and it helps me to review my work and confess my sins. Yes, I break the code of the Mechanics’ Guild and freely admit that I make mistakes and, sometimes, really fuck things up. I’ve made just about every damned-fool mistake you can think of and broken every tool and part. But a funny thing happened – as the years rolled by I made fewer and smaller mistakes. I still make mistakes – sometimes even dumb ones – but for quite a while now (knock polished alloy) they have been non-catatrophic and recoverable errors. And every one still a lesson of some sort.

Cheers,
Chris

Existential Motorcycles TEL: 828-6839289 Web: http://www.existentialmotorcycles.com
Alexander, NC 28701


So you think you want a custom cafe racer?

Posted: November 19th, 2012 | Author: Administrator | Filed under: Engine, Forks & Steering, Frame & Body, Fuel & Air, Ignition, Timing, & Electrical, Motorcycle Repair, Random Things of Interest, Wheels, Tires, & Brakes | Tags: | No Comments »

Greetings,

The following in the first installment of correspondence between me, a would-be cafe-racer builder, and one of his customers. The customer was so appalled at what was delivered to him that he forced the builder to bring the bike to me and pay me to put things right.

Caveat emptor!

Chris


John and Casey,

This is the first in a short series of illustrated reports on my findings and work on your bike.

It will be difficult reading for both of you – and it is difficult work and writing for me. I began work on your bike last evening and had to quit after 1 ½ hrs. as what I was finding was making me increasingly angry.

In short, this bike was built/assembled by a dangerously incompetent person who should never be allowed to work on a vintage motorcycle again – unless they are willing to apprentice for a couple of years with someone who knows what they are doing.

Report – Initial Inspection:

Compression test: L = 190 psi and R = 175 psi. on a cold engine.

Since the spec on a new engine is 175 psi., these numbers suggest a substantial build-up of carbon on the piston crown and head. I will put a bore scope down the spark plug hole today and have a look. Also I’ll do a leak-down test. For the price of this bike – $7k – it should have a freshly-built engine, not just a freshly-painted engine.

The electronic ignition module is located in the worst possible place on the bike – directly in front of the leading edge of the rear tire with no intervening fender or other shield to protect it from the grit/crud/spray hurled at it by the spinning rear wheel. I will relocate it or shield it.

The front brake is dragging badly – and it’s a simple drum brake – the adjustment of the cable/actuating mechanism is just too tight. Again, no excuse for this. A simple pre-delivery inspection would have caught this. No bike should leave a shop with compromised brakes.

All three Phillips head screws for the cover on the centrifugal oil filter had seized and the heads stripped out. The rust pattern in the stripped screw heads shows that no attempt was made to remove the stripped screws and replaced with good ones so that the new owner could access/clean the filter. Which suggests that the person who built this bike did not clean the filter either.

Working carefully, I was able to remove all three screws in about 30 minutes. The pix below show what I found and how I fixed it. They also show the inside of the centrifugal filter and what I found in there – the usual black sludge but with lots of small bits of metal embedded in it – steel as it sticks to the head of a magnet. This probably comes from the transmission gears and suggests that it has been treated badly at some point in its past.

First I drilled out the heads of the stripped screws a bit and then hammered a 3/8” drive torx bit into the hole. Anoint with penetrant, heat with MAPP gas, and attach impact driver to the torx bit. One good whack with a 3 lb. Short sledge and voila. Well, almost. The threads of the top/left screw were stuck so badly that I just twisted the head off the screw shank. Fortunately, I was able then to carefully lift the cover off and then get a grip in the bit of shank protruding from the case.

And finally, two of the four bolts holding the footpegs to the frame were badly cross-threaded and one on the right side had jammed half way in and been left like that, here’s the pic.

Not only does the shoddy/dangerous workmanship offend me, I am dumbfounded by the fact that the person who assembled this bike did not think or care that anyone would notice.

I am posting this series of correspondence on my website – minus your names – as a bit of a caution to folks buying a custom-built bike and to those who think that capitalizing on the cafe-racer fashion is an easy quick buck.

John, I am roughing up you and your biz – and it’s got to hurt. But it’s the truth. If you can’t stand it, refund C’s money in full and get out of the biz. Otherwise, do the harder/right thing and take it and learn from it.

Sincerely,

Chris Finlayson
Existential Motorcycles
Alexander, NC


John and Casey,

This is the first in a short series of illustrated reports on my findings and work on your bike.

It will be difficult reading for both of you – and it is difficult work and writing for me. I began work on your bike last evening and had to quit after 1 ½ hrs. as what I was finding was making me increasingly angry.

In short, this bike was built/assembled by a dangerously incompetent person who should never be allowed to work on a vintage motorcycle again – unless they are willing to apprentice for a couple of years with someone who knows what they are doing.

Report – Initial Inspection:

Compression test: L = 190 psi and R = 175 psi. on a cold engine.

Since the spec on a new engine is 175 psi., these numbers suggest a substantial build-up of carbon on the piston crown and head. I will put a bore scope down the spark plug hole today and have a look. Also I’ll do a leak-down test. For the price of this bike – $7k – it should have a freshly-built engine, not just a freshly-painted engine.

The electronic ignition module is located in the worst possible place on the bike – directly in front of the leading edge of the rear tire with no intervening fender or other shield to protect it from the grit/crud/spray hurled at it by the spinning rear wheel. I will relocate it or shield it.

The front brake is dragging badly – and it’s a simple drum brake – the adjustment of the cable/actuating mechanism is just too tight. Again, no excuse for this. A simple pre-delivery inspection would have caught this. No bike should leave a shop with compromised brakes.

All three Phillips head screws for the cover on the centrifugal oil filter had seized and the heads stripped out. The rust pattern in the stripped screw heads shows that no attempt was made to remove the stripped screws and replaced with good ones so that the new owner could access/clean the filter. Which suggests that the person who built this bike did not clean the filter either.

Working carefully, I was able to remove all three screws in about 30 minutes. The pix below show what I found and how I fixed it. They also show the inside of the centrifugal filter and what I found in there – the usual black sludge but with lots of small bits of metal embedded in it – steel as it sticks to the head of a magnet. This probably comes from the transmission gears and suggests that it has been treated badly at some point in its past.

First I drilled out the heads of the stripped screws a bit and then hammered a 3/8” drive torx bit into the hole. Anoint with penetrant, heat with MAPP gas, and attach impact driver to the torx bit. One good whack with a 3 lb. Short sledge and voila. Well, almost. The threads of the top/left screw were stuck so badly that I just twisted the head off the screw shank. Fortunately, I was able then to carefully lift the cover off and then get a grip in the bit of shank protruding from the case.

And finally, two of the four bolts holding the footpegs to the frame were badly cross-threaded and one on the right side had jammed half way in and been left like that, here’s the pic.

Not only does the shoddy/dangerous workmanship offend me, I am dumbfounded by the fact that the person who assembled this bike did not think or care that anyone would notice.

I am posting this series of correspondence on my website – minus your names – as a bit of a caution to folks buying a custom-built bike and to those who think that capitalizing on the cafe-racer fashion is an easy quick buck.

John, I am roughing up you and your biz – and it’s got to hurt. But it’s the truth. If you can’t stand it, refund C’s money in full and get out of the biz. Otherwise, do the harder/right thing and take it and learn from it.

Sincerely,

Chris Finlayson
Existential Motorcycles
Alexander, NC


John and Casey,

This is the first in a short series of illustrated reports on my findings and work on your bike.

It will be difficult reading for both of you – and it is difficult work and writing for me. I began work on your bike last evening and had to quit after 1 ½ hrs. as what I was finding was making me increasingly angry.

In short, this bike was built/assembled by a dangerously incompetent person who should never be allowed to work on a vintage motorcycle again – unless they are willing to apprentice for a couple of years with someone who knows what they are doing.

Report – Initial Inspection:

Compression test: L = 190 psi and R = 175 psi. on a cold engine.

Since the spec on a new engine is 175 psi., these numbers suggest a substantial build-up of carbon on the piston crown and head. I will put a bore scope down the spark plug hole today and have a look. Also I’ll do a leak-down test. For the price of this bike – $7k – it should have a freshly-built engine, not just a freshly-painted engine.

The electronic ignition module is located in the worst possible place on the bike – directly in front of the leading edge of the rear tire with no intervening fender or other shield to protect it from the grit/crud/spray hurled at it by the spinning rear wheel. I will relocate it or shield it.

The front brake is dragging badly – and it’s a simple drum brake – the adjustment of the cable/actuating mechanism is just too tight. Again, no excuse for this. A simple pre-delivery inspection would have caught this. No bike should leave a shop with compromised brakes.

All three Phillips head screws for the cover on the centrifugal oil filter had seized and the heads stripped out. The rust pattern in the stripped screw heads shows that no attempt was made to remove the stripped screws and replaced with good ones so that the new owner could access/clean the filter. Which suggests that the person who built this bike did not clean the filter either.

Working carefully, I was able to remove all three screws in about 30 minutes. The pix below show what I found and how I fixed it. They also show the inside of the centrifugal filter and what I found in there – the usual black sludge but with lots of small bits of metal embedded in it – steel as it sticks to the head of a magnet. This probably comes from the transmission gears and suggests that it has been treated badly at some point in its past.

First I drilled out the heads of the stripped screws a bit and then hammered a 3/8” drive torx bit into the hole. Anoint with penetrant, heat with MAPP gas, and attach impact driver to the torx bit. One good whack with a 3 lb. Short sledge and voila. Well, almost. The threads of the top/left screw were stuck so badly that I just twisted the head off the screw shank. Fortunately, I was able then to carefully lift the cover off and then get a grip in the bit of shank protruding from the case.

And finally, two of the four bolts holding the footpegs to the frame were badly cross-threaded and one on the right side had jammed half way in and been left like that, here’s the pic.

Not only does the shoddy/dangerous workmanship offend me, I am dumbfounded by the fact that the person who assembled this bike did not think or care that anyone would notice.

I am posting this series of correspondence on my website – minus your names – as a bit of a caution to folks buying a custom-built bike and to those who think that capitalizing on the cafe-racer fashion is an easy quick buck.

John, I am roughing up you and your biz – and it’s got to hurt. But it’s the truth. If you can’t stand it, refund C’s money in full and get out of the biz. Otherwise, do the harder/right thing and take it and learn from it.

Sincerely,

Chris Finlayson
Existential Motorcycles
Alexander, NC
Bad location for sensitive electronics


Cleaning/lining a gas tank

Posted: April 1st, 2012 | Author: Administrator | Filed under: Fuel & Air, Motorcycle Repair | 4 Comments »

If it’s not leaking, just clean and de-rust it and put a filter in the fuel line to the carbs. The risks of a less-than-perfect lining job are greater than the benefits – on a non-leaking tank. If the liner starts to come off, it’s pretty much curtains for the tank.

The right way to clean a tank is to first mechanically remove as much rust/crud from the inside as possible. Get a length of light chain – the stuff sold in hardware stores in bulk for hanging lights and so forth is ideal. The length is not important – 3-6ft. is fine. Some folks use a large handful of nuts/bolts – which works – but it can be hard to get them all out again. The chain is easy.

Put the chain in the tank with a quart/liter or so of kerosene. Lay a plastic shopping bag over the filler hole and then close the cap. This keeps the kero from finding its way out the vent in the cap. Now shake the tank turning it this way and that. So it until your arms get tired and then set it aside. Repeat this a number of times until the rust and crud has been scoured away and the metal is clean and bright. Extract the chain and drain off the kero/crud solution. Rinse with fresh kero until it comes out clear. Pour in a quart or so of Evap-o-rust or similar de-rusting solution. They are all based on phosphoric acid which chemically converts iron oxide – rust – to a moderately inert ferric phosphate. I use Milkstone Remover – a dilute solution of phosphoric acid sold through Tractor Supply for cleaning dairy lines. I mix it 1:5 with water – making six gallons – in one of those large blue plastic storage totes from Kmart/Target/etc. Now I can fill a tank with de-rusting solution and let it sit for a day or so. This stuff is highly reusable – and you can just toss smaller rusty bits in the tote. At this weak concentration, the acid is completely safe – you can put your bare hand in it. If you have a cut or nick, it will sting just a little bit.

Here’s a bit from Wikipedia on the chemistry:

“Phosphoric acid may be used as a “rust converter”, by direct application to rusted iron, steel tools, or surfaces. The phosphoric acid converts reddish-brown iron(III) oxide, Fe2O3 (rust) to black ferric phosphate, FePO4.

“Rust converter” is sometimes a greenish liquid suitable for dipping (in the same sort of acid bath as is used for pickling metal), but it is more often formulated as a gel, commonly called naval jelly. It is sometimes sold under other names, such as “rust remover” or “rust killer”. As a thick gel, it may be applied to slopi ng, vertical, or even overhead surfaces.

After treatment, the black ferric-phosphate coating can be scrubbed off, leaving a fresh metal surface. Multiple applications of phosphoric acid may be required to remove all rust. The black phosphate coating can also be left in place, where it will provide moderate further corrosion resistance (such protection is also provided by the superficially similar Parkerizing and blued electrochemical conversion coating processes).”

If the tank is still solid and leak-free, just use it as is but fill it with Stabil-treated gas if it’s going to sit unused for more than a couple of weeks.

If, however, you want or need to line the tank, your work has just begun.

Rinse the tank well with water – several times – to remove all traces of acid. Now dry the inside with compressed air or a hair dryer on low heat. You can speed up things by shaking/blowing most of the rinse water out and putting the tank in a slow oven – about 120-150 degrees F – for a couple of hours. Shake the tank – if you can hear any liquid inside, it’s not done yet.

Now let the tank cool, if you have used the oven method of drying, and then pour a quart of acetone in. Replace the cap and shake well turning the tank over and round about. This does two things; it picks up and eliminates any remaining traces of water and leaves the surface squeaky clean for max adhesion of the line.

The coating should be applied immediately. The acetone washed metal will flash-rust very quickly. Use a liner that is explicitly resistant to the ethanol that is present in most gasoline these days. Good liner is expensive – Caswell’s and POR-15 are said to be very good. I use Red-Kote, and industrial tank liner available through some auto parts stores for around $60/gal. I thin it with MEK – nasty nasty stuff put the only thing that will thin this stuff – and give the tank a thinned wash coat first to ensure that it penetrates every tiny nook/cranny/pore. It needs to air-dry for a couple of days before applying the second un-thinned coating – which needs to dry several days before contact with gasoline. The nice thing about having way more liner than you need is that you can pour lots into the tank to ensure that the coating reaches/covers everything – but you must take pains to ensure that all of the excess drains out so that what remains dries completely before contact with fuel.

If you are using a coating, you must either first remove the petcock and plug those holes or use a crummy old petcock as the sacrificial plug. Also make sure you put a layer or two of plastic between the filler cap and the hole before closing the cap. Otherwise, the liner can plug the vent hole in the cap and your tank will not flow gas to the carbs.


Tuning pilot air screws

Posted: March 13th, 2012 | Author: Administrator | Filed under: Fuel & Air, Motorcycle Repair | No Comments »

NOTE: the following is for twin cyl. engines – and singles too.  Fours will not idle on one cyl. so an external tachometer is needed to fine-tune them.  But, in general, just setting the screws to the spec listed in the service manual will be just fine.

Setting the pilot air screws is fairly simple.  Raise the idle speed sufficiently that it will idle on one cyl. when you pull the plug cap off the other.  Turn the idle speed down as far as you can without the engine dying.  Turn the screw in/out until you have found the spot of highest idle.  As the idle rises, turn the idle adjuster to keep the idle as low as possible.  You can hear changes in idle speed better at the slowest possible idle.  Initially, make the changes a 1/2 turn at a time and pause for ten sec. or more to let the change take effect – there is a lag.  Once you have found the highest idle, repeat but make the changes 1/4 turn.  Repeat with 1/8 turn changes.  When done, make sure the idle is as low as it will go.
Now repeat for the other cyl.
Replace both plug caps and turn the idle down to 1.2k rpm or so.
That’s it.

If you want to go all techie, you can buy an external tachometer with an inductive pickup – but the old guys did it by ear.

So I get this note from a guy in the Andes …

Posted: November 30th, 2011 | Author: Administrator | Filed under: Engine, Fuel & Air, Motorcycle Repair | No Comments »

… and this is what it said. But to make sense you should go to the end of this post and read back up. I’m too damn lazy to rearrange it for you. And please do visit Matt’s blog. He’s an extraordinary man – too smart to be fearless – but he is. I do believe the man loves living too much to be afraid of dying.

Begin copied text:


Matt,

RE XT500 – yes, more power – lots – but also more size and weight – lots too. I’ve become a bit of a crank about weight in my cranky old age. Big power is big stupid fun but the additional mass needed to keep it all more or less in line is not fun – but still stupid. See? I told you I am a crank.

My first bike was a Hodaka Ace 100 – a 100cc. 2-stroke street-legal enduro bike. It made modest power but weighed just under 200 lb. In real off-road/no-road riding, one’s rate of progress is mostly terrain and traction-limited – not power-limited. So big power is worse than useless – you can’t use it but it still comes with all that extra size and mass. Stupid. Of course, the more nearly your course of travel resembles a road, the more you can put big power to the ground.

This winter I am building myself a hot-rod to my liking – 300 lb. & 40 rear-wheel hp. (approx.). A former customer had an XR650-L that he seized due to letting it run out of oil. Usually, the damage is worst at the extremities of the pressurized oil supply – the head (cams and valves). But in this case the piston seized hard enough to break off a big chunk of the piston skirt on the intake side. The cam journals got hot – cooked oil on the adjacent castings – but they did not score or seize so the rest should be fine. When I autopsied the corpse and gave him my estimate for a resurrection, he asked for some time to think it over. After a few months I ended up with it in lieu of. And not much of a bargain at that. But I have an earlier-gen XR600R frame which is smaller and lighter and I’ve got the new higher-compression over-size piston/rings/etc. and boring the cyl. and renewing the valve faces/seats will be under $200. Say another $1k for a CBR600 front and rear end tacked onto the XR frame. Make it $800 for cables, tires and widgets and what-not. I’m leaning toward a monochrome/bare metal aesthetic – no paint, no plating – everything fine-bead blasted to a dull satin luster and clear-coated – powder or epoxy. All fasteners of silicone-bronze. The tank a longitudinal stack of three aluminum alloy tubes approx. 6″ dia. w/ends slash-cut/tapered and capped at each end. A repro-tractor seat cast in aluminum – yes, they are available for around $60 intended as a decorator item and often used as seats on bar stools in the den – I guess. Seat rigged as a springer with those cool mini coil-over shocks. No fenders. I have no idea what it will really turn out to be – I tend to make things up as I go along. But you get the gist – a light-weight thug.

Yes, opening up the airbox can only help.

Cheers,

Chris


i meant drz400…. typo there at the end.

thanks chris!

you can see pictures of the whole journey (11 months on the road so far) at www.spokecount.com. one of the best posts is called ‘’san blas
panama to capurgana colombia.”

i ordered a carb kit from keintech, but getting it delivered down here
has been an issue. i will take the carb apart and see what i find. i
seem to recall somebody on the ADVrider forum mentioning the
adjustable needle. i just put in a brand new air filter and applied
the recommended 2-stroke oil. do you think opening up the airbox
would assist any?

i am glad to hear the shop is coming together! i take it existential
MC is doing well! any more custom projects going on?

i ALMOST bought an XT500, but balked at the last minute for the
simple, reliable dr200. but i am already missing the extra umph of my
drz200 on the long mountain climbs when there are 10 trucks to pass.

and to clarify, i don’t recall ever claiming that the unicycle trip
was fun… :)

cheers,
matt


Matt,
An adventure indeed – but that’s what I’d expect from a loon who thinks a 2k mi. off-road unicycle trip is fun.

You are almost certainly experiencing oxygen starvation – or, rather, your
engine is. The carb is jetted for sea level or thereabouts and the stock
jetting usually work pretty well up to about 3k ft./1k m. elev. It’s the
main jet that is most in play at full throttle – and the stocker is
flowing
too much fuel for the available oxy at your higher elevations making the
engine run too rich – you will be fouling plugs soon if you haven’t
already. So lean out the pilot mixture – screw it out if the pilot screw
is upstream of the throttle slide and in if it is downstream – and lean out
the mid-range by lowering the needle. I can’t recall if your needle has the
grooves and a clip that makes it adjustable. If so, put the clip in the
highest groove – lowering the needle. If your needle is not adjustable
you will need a smaller needle jet. If you are having problems now at 3k m., it
will be undriveable at 5k. And even if/when you have the jetting sorted, the engine will be making significantly less power – less fuel/air = less power. Make sure your air filter is clean clean clean. If it is at all occluded,that will exacerbate the rich condition. Please do add me to the list if you are sending out periodic reports. You would barely recognize the shop these days – fully insulated, well- lit, two real table lifts, floor to ceiling shelving, three workbench spaces, organized and humming.

Cheers,
Chris


hey chris!
i hope you are doing great. i have cooked up quite the adventure. i bough a 2003 suzuki DR200 with 6000 miles on it in medellin, colombia. i am headed south fast to ushuaia, argentina, then back north slowly. now here’s my issue. when i am running between 50 and 60mph in 5th gear, i am getting some power loss. it is especially noticeable when i jam on the throttle to pass, climbing, or when a wind gust hits me. the bike ran great at about 1500m and now i am between 2 and 3000m going up to 5000m in peru, any suggestions? drill out the mixture screw, as it might be too lean? or could it be some other issue? just wonder your thoughts.

cheers,
matt


A note on winter/long-term storage.

Posted: November 16th, 2011 | Author: Administrator | Filed under: Engine, Fuel & Air, Motorcycle Repair | No Comments »

Greetings fellow motorcycle owners,

Do the right thing for your two-wheeled companion – do a few simple and inexpensive things now so that your bike is ready to ride on the first great day of spring.

Or you could wait until that first warm day only to find that your battery is dead, the fuel in the tank gone bad, the carbs gummed up from sitting full of untreated fuel for months, the chain rusty and the sprockets shot – and every bike shop in the known world is booked for weeks out with work for other lazy-ass motorcycle abusers just like you. Is there really a choice?

So here’s what you do:

A. Take your bike to one of the several shops in the area for a winter-storage prep.
B. Do it yourself.

Either way, this is what should be done.

Have the following material ready to hand:

Oil and filter
Stabil brand fuel treatment
Cable lube
Chain lube
Fork oil
Cleaners and polish

1.) Ride your bike until you have to switch to Reserve.
2.) Add the specified amount of Stabil to your fuel tank for its capacity – directions on the back of the Stabil bottle
3.) Fill the tank to the brim and ride it for five miles or so – enough to ensure that the fuel in the carbs is treated fuel.
4.) Top up the tank.
5.) While the engine is still hot/warm from your ride, change the oil and filter.
Change transmission oil if separate from the engine oil – shaft-drive oil too if you have one.
6. Clean/lube/adjust the chain.
7.) Pinch the chain between your fingers at the 3 o’clock position on the rear sprocket.
If you can pull it more than 1/3 the way up off the tooth, the chain is stretched and will only trash your sprockets if they are still good – which they probably are not.
The teeth on the sprockets should be symmetrical – not worn more on one side than the other or hooked. The ends of the teeth should be squared off – not pointy.
You will need to remove the front/countershaft sprocket cover to examine the teeth.
Worn sprockets will trash a good chain and versa vice. Ideally, they are replaced as a complete set – chain and sprockets.
8.) Replace the chain and/or sprockets as necessary.
9.) Examine your brake pads/shoes – replace if worn.
10.) Replace brake fluid.
11.) Flush and change coolant – if your bike is a water-pumper.
12.) Drain and replace the hydraulic fluid in the front forks. Consult your manual for the right type and amount.
13. Replace the fork seals at the same time if there is any evidence of weepage.
14. Remove all the control cables. Using a pressure luber, run cleaner and then lube through them. Replace and adjust.
15.) Change/clean the air filter.
16.) Replace the tires if worn more than 1/2 way.
17. Remove the battery and marry it to a trickle/float charger someplace that does not freeze.
18. Clean and polish your bike. Clean/treat plastic/rubber with Armor-All.
19. Put it on its center-stand or some other stand – take the weight of the bike off the springs and the tires’ contact patches.
20. Cover it with a dust sheet if stored inside – the best cover you can afford if outside.
21. If the bike is to be stored outside or in an unheated garage/shed, spray the whole thing down with WD-40 or some such to prevent condensation corrosion.
In the spring, spray it down with a cycle cleaner like SS-100 and hose off.

Now for the pay-off.

On that first day of spring, install your battery, turn the key, and go riding.

This public service announcement is brought to you by Existential Motorcycles on behalf of all the WNC motorcycle shops.

Cheers,
Chris Finlayson
Existential Motorcycles
Alexander, NC 28701
TEL: 828-683-9289


Just Another Day at the Office

Posted: November 2nd, 2011 | Author: Administrator | Filed under: Fuel & Air, Motorcycle Repair | No Comments »

Steve,

Of course Robt. and I had a collegial discussion on the way home regarding your bike – theorizing, hypothesizing, and devising tests of those hypothesis. So nothing would do when we unloaded your bike but to get it up on the lift and put our chat to work.

First thing, I put my meter on the battery – expecting it to be very low as per the clicking solenoid. Not so! A full and robust 13v. Still, it’s amps that spin the starter, not volts so I hauled over my big shop battery – retired from daily duty in my truck – and jumper-cabled it to your system. Same thing – click click – no joy. Finally, I cabled the shop battery directly to the starter motor. There a perceptible vibration an electric motor makes when it’s drawing all the juice but cannot turn – and your motor made it.

Now my working hypothesis is that the starter motor has seized. Time to remove it and bench test it. This required removing the left side engine alternator cover. I did not put a drain pan under the engine as there is no oil in the alternator/rotor bay. Pulled the array of 8mm bolts, gave the cover a tap with the dead-blow hammer to break the seal …

… and out poured gasoline – gushing gasoline. I removed the sparkplug and the cyl. was full to the top with gasoline. There was nothing wrong with the battery or the starter – liquid is incompressible and the cyl. was full. This is something called a “hydro-lock” and it usually results in a bent connecting rod. I put the bike in gear, shifted up to top, and turned the engine over with the rear wheel – which launched great jets of gasoline toward the ceiling. The crankcase and the air filter box were also filled with gasoline.

I have a good collection of retired cotton bed sheets that I use for dust covers when I remember them and it took a half-dozen or more of them to mop up the shallow lakes of gasoline on the lift table and floor. One spark …

I let everything drain for a while and then filled the crankcase, and turned the engine over with the spark plug removed to pump fresh oil through the system before it had to sustain the forces of combustion. I did a compression test and got 155 on a cold engine – a very good number. Fitted a new D8EA and turned it over with the choke off and the throttle wide open – the field-expedient treatment for a flooded carbureted engine. First a cough and then a few more – and whoo hee! We have self-sustaining combustion. And the engine sounds smooth and happy – not a hint of the dreaded bent con-rod.

So, why did your engine fill will gasoline? I tested the petcock – the vacuum-operated petcock with the manual over-ride in the “Prime” position. The petcock is working as designed so, after filling it, you must have left it overnight with the petcock on Prime – which I specifically instructed you was to be used only if/when the tank had run dry and the carb sucked air as it sputtered to a stop. In that case, the carb needs to be Primed – filled with fuel prior to staring the engine. Otherwise it stays in the On or Reserve positions.

But we have a second question to answer as well; if the float/float-needle/needle seat are all on the job, the flow of fuel from the tank should have been shut off by the float needle fitting into its seat. But it wasn’t. I think the clue is in the fact that you filled the tank up from nearly empty – and I bet that I find another layer of sediment in the carb float bowl. But wait! There is one other possibility – and the more likely, now that I think of it – is that the damage I showed you on one of the posts for the float pivot pin was worse than I assessed and somehow caused the float to stick open. I will investigate this tomorrow.

This is an example of the tension between saving the customer money by reusing less than perfect parts or giving them back a bike that breaks down again. Mostly my judgement is pretty good and less than perfect parts can and do give long and faithful service. Sometimes I’m wrong – in retrospect, that is. The easy thing would be to simply use new parts all the time – effectively charging my customers to cover my ass. But I do believe in using/reusing as much of our way-too-much stuff as we can.

So, all of that may or may not have something to do with the problems you were experiencing pre-fill-up. I will keep your bike for a couple of days and take it on a few short hops – perhaps as far as Weaverville. If it is trouble-free, the plan is for Robt. to take it home to his place in Marshall and have you drive your car to meet him there for some schooling.

You’re into me for a couple of hours/$110 and half of the normal pick-up fee – $25 -I’m eating half on the possible hanging float but you left the petcock in the Prime position.

A good used carb body may be required – but a whole good used carb bought to get it. Figure $100 +/-. plus another hour or so of my time.

And that’s the news from Existential Motorcycles this evening.

Cheers,

Chris

Existential Motorcycles
Alexander, NC 28701

TEL: 828-683-9289


Good sources for vintage Honda parts

Posted: July 28th, 2010 | Author: Administrator | Filed under: Engine, Forks & Steering, Frame & Body, Fuel & Air, Ignition, Timing, & Electrical, Motorcycle Repair, Wheels, Tires, & Brakes | Tags: | No Comments »

Here are links to a few sites that I have found have a good inventory of new vintage Honda parts:

http://www.cmsnl.com/

This one is in the Netherlands but I’ve gotten parts from them in a week or so – and they have stuff that no one else has.

http://www.babbittsonline.com/pages/parts/viewbybrand/default.aspx

Babbitts is good too – and they have on-line parts diagrams for just about every vintage Japanese bike.

http://www.ohiocycle.com/

http://www.classicjapanesemotorcycles.com/

http://www.westernhillshondayamaha.com/aboutus.asp

http://www.vintageconnections.com/

a source for OEM type electrical connectors, etc.

http://www.davidsilverspares.co.uk/

Excellent inventory and prices are o.k. now that the British Pound has tanked against the dollar.

http://www.hondarestoration.com/