I just installed the Stage 2 conversion:
I replaced the piston and cylinder to 70cc, replaced slides and spring, put on the Prima pipe, and changed the jetting from 82 to 95, which came with the kit. I fired it up and it started and idled fine. When I went to test it on the road, it had absolutely no response to giving it gas, just barely putt-ed. I removed the airbox to see if more air would help, and it did a bit. It didn't have any bottom end acceleration, but got up to about 35mph. I noticed if I gave it more gas, it would bog and I could feel (with my hand) a spray of gas coming out of the carb.
Is this all a jetting issue and do I just need to play with jetting until it is satisfactory? I am contemplating going to a 19mm carb and a performance air filter, but that doesn't help me today.
Thank you for your help.
Doug
Jetting help needed
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Re: Jetting help needed
2T motors are very sensitive to jetting...too lean, and they don't want to rev...too rich, and they won't revJewelryMonk wrote:... When I went to test it on the road, it had absolutely no response to giving it gas, just barely putt-ed. I removed the airbox to see if more air would help, and it did a bit. It didn't have any bottom end acceleration, but got up to about 35mph...
All other things equal, a displacement bump will tend to draw more vacuum through the carb and lessen the need to upjet.
As a start I suggest going smaller and see if it helps.
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After my 70cc upgrade and Prima pipe, I put a 19mm Malossi carb on this week with a scooterworks racing air filter, had an 80 jet in the carb from the start. I changed jest 5 times and ended up with a 118 jet in it. still has no low end, bogs down quite a bit.... no take off..., but goes good at the top end.
Plug finally looks tan instead of white.
Also changed slider weights to 6.0g and stronger spring.
I have to figure out the low end....
Any ideas?
Plug finally looks tan instead of white.
Also changed slider weights to 6.0g and stronger spring.
I have to figure out the low end....
Any ideas?