bestrcpilot

the biggest gain with the TY intake track is gained by maker the connection to the air-box the straight as possible. As most of the trouble with the intake is a pinched intake rubber hose between the carby and the air-box. If you ride it like a modern bike.IE.. lots of revs and using the clutch, then opening the top of the air box up will help it to rev better. Now if you are running a short header pipe and after market exhaust and porting then a bigger air-box and a straighter intake track dos help. IE. using a Yamaha RD 350 intake (from the reed plate to the carby.) And make sure the reed are sealing as after 35 years they are know the lift and not seal. The use a new carby as the stock one are also know the wear and and not run right. Hope this helps

The silver frame is a model 49 mark2 A replacement frame from Bultaco sometimes did not have a number on them, but check by the right foot peg .

I find that most cables for the front brake are to long which give a spongy feel to the brake as the cable flexes to much. Try making the cable as short as it can be. It does Help

If you really don't want to do the swing arm mod. Then try useing a dt 175 swing arm. You will have to redo the tabs onit but it's longer then a ty arm Just use a an early dt. By lenthing the swing arm will help keep the front end down on the hill.

Sound like the trail is wrong. Go with a set of ty250 triple trees and ty250 forks. Fixed mine. I to tried a set set of triple trees that were parallel to the headstock the bike felt like I was falling off the front end and sloppy side to side just terrible put the ty250 set up on it much better. Also use the upper triple tree that moved the handlebars in front of the pivot point..

I have no trouble with IRC tube type staying on the rim with my M49 Bultaco even when I run them down to 4 psi.

Pull the side cover and see if ignition is full of water also check the amount of oil in it and see if there's water in the oil. Change plug. Reclean carby again. Check flywheel key.

Check the points and timing.

If alloud a Mikuni 24mm flat slide works for me.

I was using condenser that I had in stock from 1974. That is why I had two go tits ups. I now use new ones and no more failures.

By all means move the condenser under the tank. When and not if it fails it' s easy to change out. Mount two that way when it fails in the middle of the woods gets youbackto the pits. Moved mine 3 years ago and doing so saved me a long push back twice now.

I think for now I will have to wait and see about when I can get back on the bike. Believe it or not but my Ty175 is down to 150 pounds now after 5 years of work. So I think I will stick with it. One of the perks of being a toolmaker. My Doctor is not motorcycle friendly and when ask about getting back to riding he said I should never get back on one of those death machines. So you can see why I asked on here.

More info was asked for so here it comes. 4 weeks post op. I'm from the orther side of the pond from most of you, the USA. I have been riding trials for over 40 years. Now on a ty175 in vintage class and rebuilding a Bultaco m49. Had my first heart attack 10 years ago and have had 4 more leading up to the bypass, with 6 stents alone the way. A total knee replaced 3 years ago. So I could keep riding. Not on any blood thinner, my blood does not want to clot on it own.

Thanks for the responses. Good to know I may still be able to ride again. Guess I don't have to sell the bikes just yet.