grizwald

Front brake plate your'e after is a late 70's YZ250 with outside Aluminium arm. This brake plate fits inside the standard TY wheel but needs two modifications. MOD.(1) Extend the existing torque lug on the left-hand fork leg by machining a small aluminium extension to fit snug inside the YZ brake plate. N.B. ( This needs to be done as there's not enough on the standard lug to fit in the YZ brake plate). You can also use the twin leading shoe brake from the last generation aircooled YZ's. MOD.(2) The second-hand YZ brake plates i've seen usually have the threaded adjuster boss broken off , so all you do is make a small angled plate in steel to replace it drill / bolt through the brake plate to attatch. Also you can use a early Yamaha RD200 front brake cable(about the right length ). I hope this has answered your enquiry. Regards Griz.

Thanks Pitley, Is the WES silencer quiet or fairly noisey? Mine sounds like an old Greeves at the moment.

Many thanks woodbutcher. Will see if iv'e got those sprockets & try it out.

Hi all, Could members advise the best gearing option for a TY250 mono (standard motor ) run solely for trials use?

Hi have nearly finished my TY mono rebuild . I've found a few problems on the way & would like to discuss them. My bike has a YZ 250 front brake plate fitted & iv'e had to machine a extended torque lug for the fork leg/ brake plate,anyone else had to do this? I also found that the carb had had a few DIY mods on it that didn't work very well.Corrected this by adjusting the float height to 23mm with the float tang just seating in the float valve slot, next fitted 42 pilot jet, highly vented air box lid, 145 main jet & needle back in the std position , air screw 1, 1/2 turns out. Bike now starts easily & runs like a top. Plastic petrol tanks don't fit very well on ty's & they seem to ooz fuel vapour & discolour (i'm thinking of getting some tank covers made). Put plenty of rubber tube compressed into the fins on head & barrel this will deaden the ringing. Question i need a good quiet exhaust silencer for the TY any ideas other than making your own? Regards Grizwald.

flywheel is standard type, marks for timing are on crankcase. i haven't ridden the bike yet but will try standard settings & play around with it as i go. Might even try the mikuni carb route as well. regards grizwald

Hi i'm rebuilding a ty250 mono & have just built my engine with a new piston that has 2 different crown heights , the centre section is higher than the sides (I presume this is to let the transfer ports open at a different time to a conventional crowned piston ) anybody know the answer? Also the original timing marks on my bike were marked for 2.8mm BTDC , but there are 4 other marks to the right of the original manufacturers mark(seems somebody has played around with the ignition timing in the past. Can anybody recommend the best figure to use e.g. 2.8mm or 2.6mm BTDC. Many thanks Regards Grizwald.