Tuned pipe...One step closer to production!



Hi all,

As some of you may know, I have been tinkering with making a tuned pipe / expansion for our little engines...Well I am happy to say I am 1 step closer to an actual production model....I will try to post some pics here now (this model is specific to the Dax 70 but may fit others as well).

The unit was designed the most difficult installation (small frame mountain bike, low rake fork, and oversized tubes) so it should fit on other bikes easily. The unit is adjustable as well without need for difficult bending. Weight is approximately 5.4 lbs. in prototype form. This pipe was designed to be far away from the riders legs so as not to interfere with normal pedaling and bicycle use.

Pipe will allow you to gear up substantially....It will pull me up the steepest of hills here in Charlottesville using a 36T rear sprocket faster than a stock bike with a 44T sprocket....I am thinking of gearing up even more in the future.

Hmmm....pics did not take...I'll try resizing since I think that is the problem.
OK another try...I think it's Gonna work! ;-)


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SIGN ME UP FOR ONE! It'd be great to be able to use a 44tooth sprocket in Colorado! I'm currently using a 50tooth and there are some hills that the engine struggles on.
Figure on a price yet? I need to know this. I hear people talk about a 2 stroke powerband. Is the Happy Time powerband with an expansion pipe the same type of powerband you feel in a 2 stroke dirt bike? I mean does it go mmmmmmAAAAAHHHHH!!!
Personally and this is just me,I like riding the bike trails and the very look of this pipe may just be the thing that would kick me out. But then again...I can always switch to the stock pipe when I know I'm gonna be on it.
If you can fit that up for the GEBE 32/40 count me in :)

I have found a tuned pipe for them but the company wont deliver to the UK *sigh*

Jemma xx
Can you adjust the carb on these Happy time engines?
I ask because if you can't, a good tuned pipe can run the motor lean,
causing all sorts of problems.

I have no experience with the HT, but a lot of experience with goped motors,
and tuned pipes. I need to run more rich with a pipe as a rule
or there is a chance of seizing the motor.