hop_sing Posted October 30, 2018 Report Share Posted October 30, 2018 I ride a modern Trials bike and want to get a TY to ride and set up our vintage sections. I found a 175 that has some mods done and looks pretty good. But the owner has a couple 250's that are not as nice. He put the 250 wheels and tires on the 175 because the tires where nice Michelin's and cut a spacer to line things up. This also means that it now has a dished sprocket on it. My questions are things like, are they heavier ? will the dished sprockets get hard to get in the future ? Is this something anybody else has done. I think it is silly he did it. maybe the spokes and rims are better or something else. but should I skip it or not be worried. I know the guy and he isn't a dummy. He says he can swap it back but I just don't know enough about the TY's. It has several other mods like the stiffer front springs in the forks and pegs done right. I am tall and it has the bar riser's. Thanks for any input. Hop Quote Link to comment Share on other sites More sharing options...
tony27 Posted October 30, 2018 Report Share Posted October 30, 2018 TY175 & 250 use the same wheels, there won't be a weight difference. The dished sprockets aren't the easiest to get but most places that deal with TYs can supply a spacer that lets you use flat sprockets My biggest concern would be your comment about the spacer, sounds like the rear wheel will be off to the right side now Personally I've always found the 175 to cramped for my height of 181cm which is part of the reason I ride a 250 even though most people say the 175 is the better trials bike Quote Link to comment Share on other sites More sharing options...
hop_sing Posted October 30, 2018 Author Report Share Posted October 30, 2018 I haven't looked at the bike recently and not that close as we where riding together and I wasn't looking to buy. The guy is smart enough to not have the wheel off center. I think he cut the spacer and moved it to the outside of the sprocket. If a different spacers are available to be able to use a flat sprocket then that should ease my worries about future sprockets. But I also am gathering that the brakes and cables should all be the same. I was thinking maybe the hub had a deeper hole for the brake shoes. I am going to go look at it in a couple days and want as much input as I want something that is hassle free. Quote Link to comment Share on other sites More sharing options...
section swept Posted October 30, 2018 Report Share Posted October 30, 2018 The TY 250 is a little heavier than you might be used to, the 175 is lighter as the whole engine unit is smaller and therefore lighter. The 250 A was quite a wide engine and the cases were aluminium, later engines had Magnesium cases, susceptible to corroding. The steering head angle is not that steep and so the steering can be a bit slow, frames can be cut and welded to alter both head angle and move the engine up and forward to gain extra ground clearance and better weight distribution, Majesty’s were heavily modified TY’s that gave the TY better handling, steering and traction. The later model mono shock forks are better, some use IT enduro brake plates that give you twin leading brake shoe at the front. Standard TY’s were made to be both road and trial orientated, so a compromise bike in many ways. Spares are readily available from Yambits, InMotion, TY off road and Trial and Trail. There are probably plenty more suppliers out there. Footrest position is a personal preference just make sure any welding has been done properly. The air filters can disintegrate if not looked after, the seat base can rust out and they can also crack across the middle and then crush the top of the air box. Rear sprockets can still be had in dished format or as already stated a spacer block allows a flat sprocket to be used. The gearbox sprocket cover can allow mud to collect and cause issues, many have been cut away to prevent this happening. There’s a bit of a list for you to go at, in standard form the frame was really quite well made and strong, so you shouldn’t fine any cracks, but check just in case. Yamaha didn’t undercoat their frames rather they just flashed silver paint onto bare metal so rusting can also be a bit of a problem. Good luck with your quest.? 1 Quote Link to comment Share on other sites More sharing options...
turbofurball Posted October 31, 2018 Report Share Posted October 31, 2018 11 hours ago, tony27 said: Personally I've always found the 175 to cramped for my height of 181cm which is part of the reason I ride a 250 even though most people say the 175 is the better trials bike I got new yokes which lost the tiller effect, steepened the steering angle, put the handlebars in a good place for a taller rider (I'm 5'10, 178cm), and allowed me to use modern fatbars that look similar to the original ones Quote Link to comment Share on other sites More sharing options...
Junglejeff Posted November 12, 2019 Report Share Posted November 12, 2019 On 10/31/2018 at 4:20 AM, turbofurball said: I got new yokes which lost the tiller effect, steepened the steering angle, put the handlebars in a good place for a taller rider (I'm 5'10, 178cm), and allowed me to use modern fatbars that look similar to the original ones Were could I purchase new yokes like you describe?. Quote Link to comment Share on other sites More sharing options...
b40rt Posted November 12, 2019 Report Share Posted November 12, 2019 2 hours ago, Junglejeff said: Were could I purchase new yokes like you describe?. Look for Gerry Minshall, he and his wife are heavily involved in the Kia classic trials series so Google him through that. Gerry is a really good guy, and manufacturers many parts for twin shock and pre 65. 3 Quote Link to comment Share on other sites More sharing options...
feetupfun Posted November 12, 2019 Report Share Posted November 12, 2019 The hubs are exactly the same on 175 and 250. The 250 uses a dished sprocket and the 175 uses a flat sprocket because their front sprockets are at different distances from the centreline. Quote Link to comment Share on other sites More sharing options...
feetupfun Posted November 12, 2019 Report Share Posted November 12, 2019 A standard TY250 weighs about 11 kg more than a standard TY175 and 10 kg of that difference is the weight difference of the motors Quote Link to comment Share on other sites More sharing options...
feetupfun Posted November 12, 2019 Report Share Posted November 12, 2019 They can both be made a lot lighter than standard Quote Link to comment Share on other sites More sharing options...
johnnyboxer Posted November 12, 2019 Report Share Posted November 12, 2019 2 hours ago, feetupfun said: A standard TY250 weighs about 11 kg more than a standard TY175 and 10 kg of that difference is the weight difference of the motors Incidently a TY250R Mono weighs 89kg and the later TYZ250 weighs 79kg So a TYZ is only 5kg heavier than a 4RT 3 Quote Link to comment Share on other sites More sharing options...
tony27 Posted November 17, 2019 Report Share Posted November 17, 2019 On 10/31/2018 at 10:20 PM, turbofurball said: I got new yokes which lost the tiller effect, steepened the steering angle, put the handlebars in a good place for a taller rider (I'm 5'10, 178cm), and allowed me to use modern fatbars that look similar to the original ones Modified a set of standard top yokes which puts the bars midway between the steering stem nut & the fork tops, improved the steering by a lot on my 250. Steering head angle had been altered in 99 to match a 99 Beta so this bike goes exactly where it is pointed Lots of other stuff done to lose weight & improve the riding experience Quote Link to comment Share on other sites More sharing options...
thai-ty Posted November 19, 2019 Report Share Posted November 19, 2019 On 11/12/2019 at 2:33 PM, feetupfun said: A standard TY250 weighs about 11 kg more than a standard TY175 and 10 kg of that difference is the weight difference of the motors .... is the weight difference of the cranks.... ..fixed it for ya.... Quote Link to comment Share on other sites More sharing options...
feetupfun Posted November 20, 2019 Report Share Posted November 20, 2019 11 hours ago, thai-ty said: .... is the weight difference of the cranks.... ..fixed it for ya.... What does this mean? Quote Link to comment Share on other sites More sharing options...
thai-ty Posted November 20, 2019 Report Share Posted November 20, 2019 1 hour ago, feetupfun said: What does this mean? the cranks/flywheels are ridiculously heavy in Yamaha 250/350 motors. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.