XR70 top end upgrade

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Good to know about the cam chain, makes me feel better.

I did probably have an excessive amount of oil in the valve guides and I don't know how much was supposed to be used in the bore. I've only run it for a few minutes because it was so late when I finished. I'll get her seated tomorrow.

Thanks
 
Okay, head bolts needed retorqued, there was an air leak causing it to run lean and hot which started burning off the built up carbon and oil in the exhaust. Not smoking at all now and running strong.

Now jetting, :O

I have replaced the 88 main with a 90 and have the needle on the 4th clip. It is running the 20mm carb, pod filter, w/ the race cam on a stock head with stock exhaust. It bogs when the boy hits the throttle quick from a stand still (flat spot on the bottom). Too early to read the plug, but he can't kick it so I need it to quit dying, or I need a decompression valve so he can start it.
 
4th from top? Should do it. Try richer on the idle air screw? If that helps but not enough, go up on the pilot.

Thanks for the follow-up order:)
 
Thanks for the tips, I put the needle all the way up (5th) and now it's running a bit rich according to the plug but stills has the bog; I'll look into a new pilot. The kit only comes with mains. It seems like the needle in the TB carb has a very docile profile, I'd like to find one with more of a taper.

I appreciate all your help.
 
Thanks for the tips, I put the needle all the way up (5th) and now it's running a bit rich according to the plug but stills has the bog; I'll look into a new pilot. The kit only comes with mains. It seems like the needle in the TB carb has a very docile profile, I'd like to find one with more of a taper.

I appreciate all your help.

I'll toss a pilot kit in with the other goodies.
 
Thanks man! That's a big hookup considering the s/h everyone wants for a single jet.
 
Off topic abit but not really...

Are there longer kickstarters available out there? My little man can start it when it's warm, but it's still tough. I think a longer shaft would help him out alot.
 
Off topic abit but not really...

Are there longer kickstarters available out there? My little man can start it when it's warm, but it's still tough. I think a longer shaft would help him out alot.

Yeah, some are longer. Gimme a length on yours, center to center, roughly?
 
the newer style china ones make it abit easier , theres also takegawa and bbr ones for abit more $$
 
The kickstart is about 6" top to bottom (this is the overall), and the shaft is 12mm+/-.
 
I got the kickstart taken care of. I have an old BW80 lump in the shed and the kicker on it has the same size shaft and is about 1 1/2" longer than the Honda! Man that makes a big difference. Just for anyone else that reads this, a pw80 has the same kickstart on it.
 

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