Trials Australia Forums

Hi Everyone,

David, you have bought to my attention another part that I would like to have for the KT. This one has lost his mate, does anyone know where to find another? It wouldn't worry me if it's cracked and or has mounting lugs missing, if so they would be a perfect match.

Greg, this one looks to be quite a good match, but is currently about 1100km away from your workshop. Would you like it posted or wait until it can be transported another way?

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.

That looks fantastic Pete especially that cool exhaust

Looks a very good job for that money, and the only thing that could be improved upon is the very long front pipe to silencer connecting tube, which will tend to stop the bike revving out fully and will reduce top end power a bit.

If I can find a wreck like that will you build me a bike like that for $600 ? I'll be over in the new year to try it out !

This year there were a couple of Fantams (Fantic top end on Bantam crankcases) competing in the Scottish 2 Day "65" event. I would guess that without the costly modern frame, and required billet alloy parts, a clubman type Fantam could be built very cheaply.

FM350 wrote:Looks a very good job for that money, and the only thing that could be improved upon is the very long front pipe to silencer connecting tube, which will tend to stop the bike revving out fully and will reduce top end power a bit.

I'm sorry, I don't understand. Do you mean the header pipe or the stinger pipe, and what length should it be exactly? Does it really matter if top end power is reduced - I was really looking for bottom end power, which it seems to have .

David Lahey wrote:That looks fantastic Pete especially that cool exhaust

Thanks to your help David.

Jon V8 wrote:If I can find a wreck like that will you build me a bike like that for $600 ? I'll be over in the new year to try it out !

No problem, I'll get started tonight

It looks a real treat, Pete. A credit to you.

Glad to hear it rides nicely too.

If you are satisfied with how it runs then no problem, but on small capacity motors the ability to rev out fully is often helpful.