Yamaha

Hi, My ty250 has plenty of power, but only at the bottom end of the gears, as soon as i hit half revs and upwards it just doesn't gain any power at-all, which means i resort to staying in the bottom end of the gears. At first i thought that this was obviously how the trial bike was designed, not the top end aggressive nature like a motocross bikes. But my friend has one also, and pulls through the gears no problem. I have a ty175 also and i sometimes think that it is definitely faster than my 250, no power issues at-all. I have changed the gearbox oil, put in a new spark plug, cleaned and checked my air filter and cleaned out my front exhaust but to no avail. I dont w…

I wonder if anybody as ever put a 250 TS TY and a Mono TY motor on a scale ? I am in the process off rebuilding a TS and find the motor heavy. Guy

TY 80, the bike starts and runs but when put in gear you have to rev it up and push off while releasing the clutch to get rolling, once its in the power band, runs great. Is this the way the TY80'S run? The topend sounds tight. I would like it to run slow and zippy while in 1st gear, any Ideas? sam

I just got a TY from Canada, about 3,000 feet or 1,000 meters higher than Maine here at sea level. It won't run without the choke at idle. There's green slime in the carb on everything made of brass. I'm wondering if a re-jet is required, I know it needs cleaning at least. Are there recommended jet sizes to start from? Also, someone removed the oil injection, but I see a line to the intake in the front of the carb from the pump, and I was wondering if that should be plugged off. Back in the 80's, I removed the oil injection off a Suzuki TS185, but I drilled holes above the main bearings so fuel mix could get in there and lubricate them. Before I tear this all apart…

i have just re-built the bottom end on a ty175 i bought as a basket case, thing is it wont run off tickover unless the choke is pulled out. i have dismantled the carb twice and i am confident that its ok. it starts first kick, ticks over, but refuses to run if i try and open the throttle, as i say, if i then pull the choke on it will rev cleanly for a few seconds untill it then chokes up. any ideas?

Hey everyone, my dad owns a 74-76 (not sure of the year, blue and white paint) Yamaha TY250 an the sprockets are pretty shot. I've tried looking online for new ones that use the 428 chain, and haven't come up with anything. I did see a European site that stocks sprockets, but uses 520 chain. We recently had to put a new chain on the bike, but had to use a 420 and not a 428, which may or may no be a problem if I order the stock size sprockets. Basically, I was wondering if it would be better to order 520 sprockets and chain instead of using the 420 chain and looking for 428 sprockets. They seem to be hard to find, and since we only use this dirtbike to peddle around on the…

Hi, I am looking for informations about a Yamaha trial bike. The engine is a TY175 and the frame looks like a mini majesty converted to monoshock. Are you aware of such bikes ? Regards

Hi all I am interested in modifying my standard TY250 engine to a 320 I would like to buy a replacement cylinder and head so that I would always have the original parts to fall back on if needed. Would any of the TY twin shock cylinders be ok to use for the conversion? There is a cylinder on ebay at the mo but the guy does'nt know what year bike it came from. From one of the posts it said to use a DT360 piston, I have only looked on ebay but they only look available in the USA. Does anyone know of a supplier in the UK? The Majesty site wants £150 for a piston kit but it looks like I could get a DT360 kit for approx £100 from the USA. On another post one guy asked …

Hi guys, I'm looking to get my 1978 ty250 ported as it's very flat at bottom end power,any recommendations where to get it ported/ rebored?

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…

Hello, i have a TY175 that needs electronic ignition as the points need changing and i thought it best to do it once. Any suggestions or recommendations out there? thanks

I am looking to improve the front brake on our TY175 and am thinking of converting it to disc. I have been looking for a front end off a broken Gas Gas or similar. Have any of you chaps carried out such a mod and have you any advice? Thanks Eiger.

Can anyone tell me the correct length of spoke to lace a tubeless rim to my spare TY hub, have a spare wheel and just tried a quick rough build with ten spokes and they are slightly too long, just wondered if anyone that has done it has the correct measurement to hand, if not will have to take it to a wheel builder. thanks

After my getting the clutch as easy as I could at present , I taught my little one how to ride his "new" bike ... 1; clutch to stiff for small hands ! 2 ; Stock throttle (and oe slide spring ) too light ... 3 ; Dads porting and expansion chamber de baffling , extra OOMMPHH ! (will lift the front end in 3rd gear on it's own w/my 200lbs on the seat !) 4 ; Trying to pull in clutch to stop (like DaD told him !) , jerks throttle WFO too ... and crashes into house... 5 ; big ole tear rolling down cheek and first words " is MY bike ok ? " and I have to say , Bike is fine , your not broke , and you will never forget your first good crash (house dented ! ) So I've got a sl…

Hello everyone, I am planning to rebuild my engine later on in the year, and was wondering about a few things. I am going to give it a new big end and little end, along with main bearing etc, the plan is to do it all at once then I won't need to strip it again for a while. If it needs a rebore, I want to take it out to 270, but I also will want to get the inlet shortened and get the head and the top of the barrel machined down a bit to raise the compression. I have heard that Birketts are the best place to get this done, but do they have a website I could look at? If not does anyone have a phone number to hand for them? I also have a very large amount of modifications…

Hi all , it seems there are lots of different rear shocks out there, some rated at soft and super soft action ect and i am 95 kg so need stronger spring rate to go on the shocks . I would have said you needed stiffer shocks for stronger springs , what do you find works best??

Hello esteemed, revered and acclaimed masters of mechanical know how! i have found tillerman6's posts/replies enlightened learning and would like to thank you all for your input. Thank you sincerely as no here (in NYC) even seems to know what a trials bike is! so question 1, as a noob who is trying to get more confident, i was feeling inspired to try and do a top end tear down and learn more about the piston/chamber etc and at least assess current conditions and hopefully allow me to feed the addiction of buying new parts if needed and replacing (or stashing for later)... having already asked on here about the oil seals, and been encouraged to go down the …

Hi, I've just acquired a 1979 Ty175 majesty and whilst I intend to trial it, the tank needs painting. So, I thought I might just as well try and use the correct white. Can anyone please tell me the paint code for the tank, same for the frame. Thanks

Theres a Ty175 for sale on Ebay and the guy reckons its a Majesty. I cant remember myself but I thought there was only two.. the mini Majesty with the straight down tubes and then the one with the bent down tubes which I thought was the original Majesty, anyway the guy selling this one thinks its an original...anyone know any better..have a look... HERE

Here are the before and after pictures of my TY175 It is now a TY200 Before And the after It's took almost year and lots of new and rebuilt parts. But I'm glad I did, it's a great bike to ride.