kevin j

Wasn't castrol R the full racing castor bean oil product? Great lubrication but nasty if left in the engine a week or more. Lots of maintenance and flushing on shutdown, etc. required to get it out of the system before storage. The synthetics have sort of taken over the high performance market. I don't know anything about 2s racing anymore. jon stoodley be the man... k

I run 50 or 60:1 with synthetic oils in the air cooled yams. 80:1 in the water cooled moderns. k

The adjusting screw would only affect the plates if the lever couldn't move. In stead of pushin g on the plates, it justmoves the lever back in the spiral plastic gear in the opposite direction. The lever moves back and forth in the spiral, so you want it centered about the arc it will make when operating, as the prior post described. The spiral gear and lever are NLA from Yamaha and a weak point, so treat them carefully. Keep cleaned and lubed and a good chain tensioner on the bike. The chain throws sand and crap right up into that area, so it gets sticky and wears. Also, if a chain comes off it often bends the push rod (which is easy to get) and damages the actuator (which is NLA and thus already gone from most boneyard carcasses). Bob Ginder at B7J also has an adjustable pivot point lever to get softer pull for little hands. is the freedom lube tool the same as the yamaluber? I have several, they work great. I did learn not to gently squirt the lube in the top, as it tends to just come back out around any leaks. Give it full blast, as much and fast as possible, and let it leak out around the top if it happenss. But that builds enough pressure to push the lube down, and pushes dirt out the bottom. Never lube from bottom up. Great tools. Thankfully, hydraulic brake and clutches reduce need for this maintenance, but throttles are still cables..... k

theyhave a very heavy flywheel, but 4 secs is toomuch. flywheel effect is a second or two. I agree, look for vacuum leak. spray water, use wd40, or propane from and UNLIT soldering torch bottle. when you find the leak point engine soudn will change. If it is alternator or crank side seals, this doesn't work of coruse, but for carb boots, manifold, etc works well. k

what is the failure mode? has anyone done any home preventive remedies? If the issue is shorting to outside, maybe a dip in the electricians glyptol or something like that ahead of time? prior to the soap water gaining entrance. If it is internal shorting, ..... not much can do there. I will seal the case carefully and add a vent hose, like the old Yam and the old GG... Wishful thinking, I assume if that simple the factory would have already done it.... k

half links are not as strong, because of the offset bend in the metal, so most mfr avoid them. What is changed, different sprockets, or ??? was it always that way? kcj

my son has on 02, we got last year. I am told the stator problem is 03 and later, and the water pump case corrosion issue is 03 and later with magnesium cases. Anyone have direct experience otherwise? I have no reason to doubt the info, but just need to know if I should be sparing an expensive stator. And I do have oil in anitfreeze, although seals I hope sort that out. k

more info please, part numbers, etc. and pics of your bracket if it is not obvious. Can I buy on inet, I am in the US Son got a 2002? Rev 3 last year and I just want to accumulate some parts before need arises. Broken kickstart lever was I think $125, ouch. I am also looking for clutch and brake master cylinders, hoses, calipers, shifter ever, maybe some wheels. Really nice bike though, big leap from his old 96GG and our 2000GG tks, kcj

I put a 2000 gasgas front brake and wheel on my TY350. way easeir and cheaper and works great and easy to get parts. Actually was spare parts that I had for kids bike, and just got to thinking it might owrk. Way easy. should be an earlier post on here with some pics and dwgs. if not, send me a message and I'll email pics and details. I would like to hear from someone who has converted the back though. Don't need disk there, but want to get tubeless tire.....disassembly and patching a tube type is a PITA. kcj

The two plug theory had a couple reasons, both somewhat based on misconceptions, so both likely marketing or hype that was never used: 1. hot pug in one spot, cold plug in the other spot, in attempt to not have detonation at high loads and speeds. Road engines. Wrong, a hot plug causes detonation because it heats up from combustion, not because it is firing. So it still caused detonation. 2. One plug fouls, switch to the other. Somewhat true, it could help, but often if one fouled it is because mixture of fuel or oil is off and the byproducts fouled the plug, or the ignition is weak and can no longer fire the plug. The other plug in the head has the same mixture and carbon, the fouling is byproduct of combustion, not really related to if plug is firing or not. Possibly being in different places in the swirling mixture might mean one plug fouled and the other didn't, but I wouldn't bet on it. Big aircraft piston engines had/have two plugs, two complete ingitions sometimes, partly for redundancy and safety, partly because the combusiton chambers were so big, and supercharging so heavy, that the combustion needed to start from two places to burn faster and prevent detonation under heavy load. The flame path is simply too long with one plug, the heating up of the charge puts it into detonation. Soem aftermarket heads had two plug places so could be used on two models with different exhausts. Whichever port was accessible was used. Or the compression release of course. kcj

I have learned with the older stuff to have all parts in hand before teardown. often, what seems routine maintenance hits a snag because a part is NLA from the dealers. For example, I have heard that TY350 mono Z spokes, and piston rings are NLA. Since the bore is chrome, rings have to be casit iron. Most aftermarket (Wiseco etc) generic rings are chromed, for cast iron bores.... Thankfully I have a few spares for my lifetime.... I guess the head gasket quoted is an example- that one seems incredible.... kcj

does sound like an air leak somewhere. tips I got from this board: 1. while running, run water across the assorted joints of the engine. Sucking in minute quantiy of water will seal the air leak briefly and engine sound will change. 2. spray with wd40,same effect but messy 3. Use small butane/propane torch UNLIT to apply butane various places. If it sucks in the fuel gas, it changes engine sound. (butnot in the electricl area with points making sparks!) I have done all three and they work. Sounds like you have verified the slide is working right, butr FWIW for others: TY80 carb has a small brass index pin in carb body that keeps the slide aligned right. That pin tends to work partially out, causes slide to hang up at part stroke or just off idle or full stroke. Push it back in and dab some epoxy on the outside of the carb body at the small boss where the pin is pressed in. kcj

does it need to be welded/plugged? If there is a screw into it for some bracket, you could coat the screw threads with loctite sealer (the weakest strength) and it should work ok. k

never had autolube! Twinshocks did, but more serious off road engines never did. More weight of pump and tank, more complexity to fail, less directly related to fuel flow, and added to throttle cable pull. premix a good synthetic oil, use some race gas blended with 92 octane. Not sure of 250, but 350 needs about 95 octane to get rid of the hot pinging, even with head gasket removed. I run about 60:1 or so. Eventually you might want to trim the flywheel to reduce the overun when slowing down the engine, and add cutch extender to soften the lever. enjoy it. k

never had one! premix a good synthetic oil, use some race gas blended with 92 octane. Not sure of 250, but 350 needs about 95 octane to get rid of the hot pinging, even with head gasket removed. I run about 60:1 or so. Eventually youmight want to trim the flywheel to reduce the overun when slowing down the engine, and add cutch extender to soften the lever. enjoy it. k

different 'valves' though: the two stroke disc valve controls inlet to the crankcase. It only has to seal a few psi, and always atmopheric temperatures hence little lube problems And the premix carries its own oilmist. Old Kawasaki discs were like masonite or bakelite material. 4 stroke is actually sealing the combustion chamber pressures and temperatures. hundreds of psi, hundreds of degrees. Did engine research for my MS degree. Part of that was the literature searches. I got off on many totally unrelated but very interesting bunny trails about engine ideas through history. literally hundreds of spark plug patents, etc. WW2 era British piston engine war planes took the engine designs to the peak, especially given the low octane fuels, poorer lubes, and metallurgy. Amzaaing what was done, obsoleted by jets, but laid groundwork for much of the high performance engines of later and today. fascinating to me. k

TY had 4 speed. N at bottom so easy to find for little kids. Later GT or MX80's had 5 speed. When my kids were younger, I looked at converting because of the big jump between first and second (I am thinking like 30% or more) but it turns out that 5th just adds to the top. And the ratios between 1-2 and 2-3 were similar so I couldn't just sprocket down and run 2-3. There is a plastic spacer in there in the TY, or was it the MX..... On the 5 speeds they just delete the spacer and put a gear in its place. Strange, would think for the few dollars they would have all been the same, but.... So I abandoned the changes, k\moved the kids up later on. manyyears back. tirs are hard to find. 14 rear, 16 front, many choices but all were narrower and not trials pattern. Only ones I knew of 5 years ago were Cheng Shin (sp?). Hard as nails, but they fit between the forks, swing arm, etc. good little bike. I will try and send you a file of information and notes, in couple days, they are at home. kcj

Two great sites that lend further suupport to your thesis. http://www.dhmo.org/ http://en.wikipedia.org/wiki/Dihydrogen_monoxide_hoax

ebay usa used to have a guy selling CD with Yamaha parts fiches info and another with Yamaha owners manuals.

CAUTION!!! it doesn't work with little kittens what, they plug up the drain?

what is aroldite? I've heard of using same process with superglue (cyanoacrylate sp?), or 'JB weld' (a grey two part epoxy/metal type paste). k

I can't find the direct link right now, but someonewhere on the the scambaiters site are 'The Quotations of Cole', the year long saga of Wilson and the Anus laptop computers sales. So hilarious it has to be made up, but so far beyond that it can't be made up! scambaiters is fun site. anyone who has done ebay or other ads has had them. I had an offer for $3500 for a TY350, to ship to africa....... if only....... http://www.419eater.com/ kcj

I am in US. I have/had several TY350 as my first 'modern' bike, but having never ridden a 250, my experiences have nothing to compare to. very slow response due to heavy flywheel (before trimming), runs out of breathing at medium revs because of limited transfer port size. basically pick a gear, anything other than first, and run the whole section in it. pulls strong. tough as nails though, heavy now, high pegs, etc as you would know from the 250 I have a 250 cylinder, assorted spare bottom ends, want to find a head and source for piston & rings to put together a 250 for fun someday. Supposedly with some porting they veel much more modern like. The 350 is a world of its own I guess... kcj

two cautions: I would not run without gearbox oil, as even with no load everything is turning, just not dogged to the output shaft. Second, you might need to run if for several minutes probably to see the effect. Once a film of oil is sucked into engine via seals or via normal premix inlet, it takes quite the time to purge out. SAE research tests with radioactive traced oil showed rapid decreases in the oil effect in seconds/minutes, but some traces still there as long as 30 minutes. You could spray some water or wd40 on the alternator side so see if sound changed for air leaks. Since you suspect oil side leak, and deending on what you run for premix oil, maybe run on gearbox oil and see what the sound and exhaust smell are like. Then change to synthetic premix 2 cycle oil in the gearbox. If the exhaust now smells way different like a modern bike, might indicate it is sucking in from the clutch side seal. Are the main bearings in good shape? loose mains tends to suck through seals, and drive the ignition points settings goofy. kcj

Having changed all of the things that you mention, it could be the brake line failing. If the integrity of the pipe has gone, then the pressure will be being wasted expanding the pipe and not being applied to the piston. nope, that just makes it spongy, will still develope the same final pressure. Now, if you have a piece of lining of the hose causing a restriction, can stop the flow. but I'd focus on cleaning pistons pads and disc. kcj