Yamaha

recently bought a 1975 yamaha ty 80 b. i run fuel oil ratio 40 to 1. do you need expensive 2 stroke oil. will using i use semi synthetic cost around £9. should i use castrol or will regular scoooter motorcycle 2 stroke work.well. also what compression should a ty 80 have the haynes manual states 78 psi warm engine>?? 78 psi seems low. piston and rings look ok think there quite new by the looks. rings and bore seem ok. i can get photos if needed not an expert on engines just picked up some knowldge over time..iIhad to order new head gaskets studs becuase the owner before had used a cut off piece of gasket.it was circle had the edges cut offf and it failed. had exh…

So here is the last part to be burnt out or cleaned in some way. I was thinking maybe some drain cleaner? Drano or something like that? MEK? As you already may know, the exit hole is very small. So this does not lend itself to cleaning with a scraper or screwdriver. I have to go and get two more gallons of degreaser and soak this thing again overnight. but any thoughts are much appreciated.

How much fork oil per leg and recommended wt,also what is point gap and piston position before tdc?

I have a ty250 pre pinky, with a leak on the gear selection shaft. Does anyone know the part number, I am in thailand and these numbers are hard to come by.

I just wondered what some of the engine mods people do to the TY250 engine. I rode another TY a while back and it had unreal power from idle and pulled like a train. That engine pulled like a modern engine and I just woudered what type of modifications had been made to the motor. I have had mine a while now and sold the modern bike so I am only going to ride the TY. It suits me and I love riding it but I think I am ready to see what can be done with one. Anybody taken thier TY past stock? I just picked up another frame last weekend and am going to put some Hebo pegs on it while moving them down and back. Then I might have the frame powder coated. Next will be to find anot…

This part of the tail pipe accepts the end plug assembly you see in the last thread above. It is also steel construction. It looks like there is a baffle inside there that is most likely welded in about half way down the length of the tube where the diameter starts to change. .? The baffle has several "spokes" to it and makes it look like the center of an old mag wheel. This is where I think the main part of the obstruction for the exhaust gasses was located. I have already poked down in there with a coat hanger and not much is coming out now Sorry for the poor image quality, but it's hard to take pictures in a black hole! . I also soaked it with degrease…

Since we seem to have several regulars who have experience with TY250's I have a couple of questions. I have been riding a Model 92 Sherpa T in Trials this year and have just finished getting my TY250 up and running. Rode a couple of sections and found the riding position to feel strange. The TY must be 2 or 3 inches higher than the Sherpa T (foot pegs anyway). I find I'm bending over quite a bit to hold the handle bars. Have you changed the handle bars or do you get used to it? Have you changed the position of the foot pegs? Without going to anything really wild or expensive what changes have you made to the bike? If I can get a few more hours of riding time I …

So I'm riding through a section this past Saturday and hear a light rattle sound from the front of the engine ('74 TY250). Shut her down and just turning it over with the kick starter could hear metal parts moving around loose. I have pulled the engine apart and found a broken ring, small end bearing with a lot of slop and a cir clip missing. The ring caught in a port and broke the ring land so the piston is trash. Found no metal parts inside the engine - don't know if they went out the exhaust or down into the case. I have washed the cases out several times with kerosene (then turned the engine over to drain it out). Nothing has come out - pieces wise. Bore wasn…

Hello. I'm a new member here and am working on my dad's 76 TY175. He had broken the frame muffler mount many many years ago and had just bailing wired the muffler up to the frame and now that I'm working on getting it running again, I want to fabricate a new muffler mounting bracket that is welded to the bottom of the rear-right seat frame tube. Would it be possible for somebody to draw or trace that small triangular bracket and email it to me so I can reproduce it (somewhat) and weld it to the frame? Thanks for any help or references provided.

Does anyone know the correct float level for the stock carburetor on my 250A ? The bike runs decent,but while cleaning the carb today I noticed the floats do not sit parallel with the carb base.I,m not sure if I will mess with it or not because it runs ok.

hello, well, my rattly old ty is not rattly anymore, having been rebuilt with a relined cylinder, wossner piston, new rod, big end and mains etc. the timing is spot on. the jetting is less spot on (work in progress) not sure if this is a new thing, or if the bike always did it - but didnt notice because of the bad rattles it made before - but on over run, it makes a sort of 'dongk, dongk, dongk' noise .................. I have read about the 'pipe bang' problem (on usa sites mainly). is this normal for a ty? pjme did all the machine work and the bike was put together properly - otherwise its all fine. thoughts appreciated.

Hi I got my kick start shaft problem resolved. the question I now have is how much preload should the spring have,

A friend ask me about taking off the oil pump on is TY ( 493-101 ), no problem just take the front cover off, unscrew the pump and pull the shaft and bushing off install a cover with a gasket: voila! the pump is out ( just block the oil intake at the motor ) I never had one that had a clip inside the clutch cover. Was I just lucky ? And If I want to replace the standard light with LED any advise ? Guy

Well this old bike is still giving me surprises and while I'm waiting on the cylinder re-bore and new piston, I thought I should look at how much crud was hiding in the tail pipe. Not to be disappointed, the tail pipe decided to cough up a couple of peanut sized chunks of pure carbon. So I know there is more in there somewhere. took off the expansion chamber too of course and it was not as bad ( I think) but the engine (when it was together) would belch 2 stroke smoke from all angles when it first started up. Could be that this carbon was what was causing the detonation during deceleration? Something was definitely going on in the cylinder. (see pictures below) …

G'day folks, ex pat from the Midland centre now based in Queensland Australia for the last 38 years. I spend more time working on bikes these days than riding them, TY Yamaha's in particular. I think its a general problem but all the bikes I see have some level of rust pitting on the stanchions. 1; Is there a sure fire way of fixing this problem besides getting the tubes hard chromed which costs more than most TY's are worth over here. I've heard epoxy resin or araldite can be used and smoothed down but how successful is it ? 2; Where can I buy new stanchions from in the UK or anywhere else, TY175 in particular. 3; Coming to ride t…

Does anybody know if genuine Yamaha pistons are still available for a twinshock TY250?. I've got hold of a 'pattern' piston from a UK Yam spares dealer and it's been nothing but trouble .........any help would be appreciated.

Just about to send off my cylinder to Millenium Technologies for re-work. Trying to source a new upper end con rod bearing for the 74 TY 250 A. I have sources for everything else. The part number listed in the factory documentation says it is 93310-21854 But the one I found at Yamaha Partshouse (Babbits) was listed as 93310-218A6-00 . Don't know if this is the same part or if someone has a cross reference list somewhere? Or if there is a NOS part still in the wrapper that someone is willing to part with? Just trying to avoid a SNAFU at the time when everything goes back together. The old bearing was missing a roller when I took it out of the engine.

After some searching on Ebay and my local Yamaha bike shop (no help there) I am wondering about my next top end overhaul. I don't ride it much, but I noticed last time out that it was dinging a bit louder than I would like going down hill with the throttle closed. From what I am seeing, the time between overhauls on these 2 strokes is on the order of 30-40 hours! So I'm going to do a compression test as soon as I can fabricate a right angle adapter for my compression gauge hose. The hose I have with the compression gauge is too stiff to allow it to thread into the spark plug hole without risking damage because the frame is centered right above the spark plug hole. …

74 ty 250 was running great for a year then it started breaking up and when you are accellerating it wont rev up. cleaned carb cleaned points and reset timming any ideas Thanks Jim

Salutations oh ye revered masters of mechanical knowledge and expertise! johnny here in NY with (yet another) question. im sorry if im asking too much, but my wife seems to be of no help and completely uninterested. This tank just came up for sale and the guy only wants 100 bucks for it. i was thinking of it as a spare but i am out of my depth in assessing the rust damage on the underside of the tank. the seller says it has pin holes leaks and will need work but i think it looks in ok condition other than the outside rust? if that rust went all the through then would it need to be welded and would this strip off the last of that nice paint? On my current origina…