power limiter for yz 80?

[KIWI KDX]

hey all, i just picked up a 92 yz80 to teach my wife to ride on,
i know a 4 stroke would have been better, but i got offered it for 200 bucks with a blown top end, worn bottom end and stuffed barell, and was intending to re power it with a 4 stroke.

now once i pulled it down, all it needs is a piston and ring!!!!
so is too good to re power. what a score!!!!!!!!!!!!!!!!!!!!!!

anyway i want to try to limit the power, hard on a 2 stroke i know! all i can come up with is sleeving the throttle cable inside the carb, so it only opens so far.

any other ideas?????

 

[ttoks]

on an 80 it's going to be very difficult, and since the YZ 80's don't have a power valve that only makes it harder, limiting the throttle is going to be a must.

 

[ZOMBIE666]

the power band on those things are snappy as hell. not sure if anyone makes one for an older 80 but you could try a flywheel weight. they smooth out the power curve a bit.

 

[rostifer]

Here's one for you. It's quite original. You ready... twist the throttle less. But the heavy flywheel Idea's a good one

 

[justalonewolf007]

That is pretty obvious rostifer, I think his question isn't about not going as fast, but making the transition from slow to fast tamer.

The problem with two-strokes (mostly the 80cc models) is that there is no power in the lower end. If you try putz around more slowly, you foul spark plugs.

Limiting the amount the amount of throttle twist doesn't seem like the best way to handle the situation. Limit it too much, and the bike won't do anything; the end result will be frustration.

Your best bet is the flywheel weight, and close supervision and instruction for the first few rides. Teach her how to use the clutch to "limit" the power if she gets scared. (It's not just for shifting!) Another good thing is to teach her how to let go of the throttle (surprisingly people get scared and "freeze" when the bike hits the power band and takes off. This happens a LOT!).

 

[KTM Mike]

I suspect the underlying issue is not the total power, but how the power is delivered - little on the bottom - then WHAM the power hits when it comes up on the pipe.

As already stated - flywheel weight can help notably. Steahlyoffroad.com

Also I suggest a G2 throttle cam - works great. Makes throttle contol much easier and more progressive. 3 cams - three curves - standard then progressivly less agressive. result is it changes how much twist vs how much throttle opening. Do a search here or on KTMtalk.com . G2 helps with the freezing on the throttle noted above - due to it working more progressivly

Jetting might help - some bikes (some KTMs) used a 3 taper needles - when it hit the transition points - a spike in power delivery, or a "hit". Straight taper needles address that. No clue if that applies to an older YZ 80 or not.

Different pipe - dunno what is available for your bike, but some are known to make better bottom end vs top, or to smooth out the hit.