When i intially installed my grubee 50cc motor on my mountain bike i could cruise at 22-24mph. After 325 miles on it started to only run around 17 mph top end. i figured out it was running extremely rich one day when i accidentally left the fuel valve off and at the end of the gas supply it sped back up to 22 before running out of fuel. I messed with the float and needle a bunch to no avail, then i took the advice i found on the board of placing a small wire in the main jet and bammm.... 23 mph. soldered up my main yesterday and drilled it our .004" smaller and she is running good as new!!
what a difference a jet makes!!
- Thread starter ssvincels1
- Start date
Your altitude (above sea level) also plays a big part on jet size selection.
Here in the Denver area, roughly 6000' above sea level, I solder and drill all my jets to .024. The 'C' clip on the second from the top. I have had better luck with the old stand-by NT carburetor than any others I've tried. It seems to be better matched to the HT engine for all-around performance.
Tom
Here in the Denver area, roughly 6000' above sea level, I solder and drill all my jets to .024. The 'C' clip on the second from the top. I have had better luck with the old stand-by NT carburetor than any others I've tried. It seems to be better matched to the HT engine for all-around performance.
Tom
Good point Tom... I've found the NT carbs as equipped stock are jetted perfectly for my altitude (actually all the carb variants seem to be) - which is at sea level & sometimes below, depending on tides & storm surges lol
ya im @ 20 ft above sea level so i figured it would be lean if anything. i have a cns epa approved carb on mine. i grew up messing with only fuel injection on all my vehicles, just getting used to messing w the carbs.
...hmm, I shoulda been more clear - I've run NT, Speed & CNS V1 carbies & never needed to rejet (sea level), but I've (fortunately?) never had to mess with the "EPA" CNS... which I believe is the 2nd or even 3rd variant.
I quite like the CNS V1 (version one), but for absolute simplicity w/almost the same preformance I'd again agree w/Tom & defo reco the NT - the ever so slight differences between even the V1 & the NT aren't really worth the aggravation if you're not used to carb shenanigans *shrug*
I quite like the CNS V1 (version one), but for absolute simplicity w/almost the same preformance I'd again agree w/Tom & defo reco the NT - the ever so slight differences between even the V1 & the NT aren't really worth the aggravation if you're not used to carb shenanigans *shrug*
