TRX 70 Carb Question

[WOODY 96]

I am waiting on a TB 88 kit w/carb & cam for my 2005 CRF70. I also have a 1986 TRX 70 in mint condition. The TRX has a bog in the engine just off idle and it doesn't seem to have a lot of power. I have rebuilt the TRX carb with two different kits but still has same problem. My question is this: is the carb and intake tube on the CRF bigger than the one on the TRX? Would it benefit the TRX to put the carb & intake off the CRF on it? Would the stock CRF cam help the TRX? This is all new to me I have always been a big bike guy.

[dirtbkr188]

The CRF cam is a bearing cam, and will not fit in the TRX head, which is a journal-type cam.

The stock CRF carb is a 17mm, I believe, and it should bolt right up to the TRX head....but....doesn't the TRX carb have twin fuel inlets and the fuel petcock mounted to the carb? If so, you will have to use a "T" fitting to make a two-into-one fuel supply line, and also add an inline fuel shutoff.

[WOODY 96]

Thanks Dirtbkr188,

I was a little worried about the petcock being mounted on the carb of the TRX. If I use a "T" fitting I will not be able to turn the fuel off unless I find some sort of detached version of petcock. Bye the way, when you said the carb should bolt right up to the TRX head, you were talking about the intake manifold and carb from the CRF, not just the carb alone right? Thanks for the info on the cam too, maybe I should have gotten the TB 88 kit with the race head and put the whole top end off the CRF 70 on the TRX 70 to modernize it. I guess I'll wait till it gets here then decide if I want to tackle the TRX project right now. Thanks!

[dirtbkr188]

Yes, you can use the intake and the carb from the CRF on the TRX70.

[WOODY 96]

Thanks again!!