New to the trials scene but wanted something to take to CD9, and managed to pick up an old CT3 Yamaha off a mate for free that had been sitting out in the weather for a number of years. Surprisingly, the motor was in great condition and still on standard bore.
Stripped the bike down to the frame and then set about modifying it with the help of some invaluable input from David Lahey and John Cuff (JC1), which included lowering the seat rails, pulling the head angle in, increasing the ground clearance, changing the trail and repositioning the footrests.
Wanted to use the original CT tank so cut 25mm out of the centre and made up a screw-in cap to replace the flip-top original.
The pipe was a source of much discussion, and ended up making one with a long header pipe, shallow diffuser, steep baffle cone and fitted a baffle tube inside. Made an aluminium muffler packed with fibreglass to keep it nice and quiet.
The CT frame has a centre backbone so the pipe was made to run down the side to the swingarm pivot and back up, and tucks in quite nicely. Made the obligatory rhs sidestand.
Made a linkage for the gearlever as my left foot is not 1 metre long.
Rebuilt the engine just with bearings, seals and gaskets and a standard piston and rings ($20 off ebay). Rebuilt the wheels, painted the frame, tank and guards (the green may offend, but it's what I had in the shed), made the seat and got it covered outside. The front guard is off a softtail Harley with the original CT mounting brackets and the rear guard is a fibreglass Montesa Cappra replica.
Total cost was under $600 as I used a lot of bits and pieces out of my junk pile. I gave it a run yesterday and it pulls nicely from nothing and seems to work quite well. All in all, a good fun project.