New carburettor, loss of power

Sean Clarke

New Member
May 21, 2018
Hey, I just bought a high performance carburettor and installed it on my bike engine. I had no room for the air filter so I am using a stocking and hose clamp as a filter. When I tested it out I was moving much slower than I go with my stock NT carburettor which doesn't sound right. I have a windowed piston and I run 18:1 mix fuel (what the manual suggested but is this too rich?) When I go full throttle the revs sit at a spot where they sound different, kind of borey.. How can I get it to run better?


Well-Known Member
Sep 30, 2012
my answer would be to go back to the carb that ran well, but that's just because I hate carbs that are sold as 'performance' or 'racing'

most of them are nice, but not jetted for these motors - you'll spend a LOT of time trying out different jets to get it running well

you might get some real benefit out of it after tuning, but that may include changing exhaust to match the new carb
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Well-Known Member
Mar 15, 2012
Santa Barbara, CA
18x1 is a bit rich....I think that 24-32 to 1 with a good high quality 2 stroke oil is fine. Also, you can try different jets to find that one that makes your bike run best. Often times the stock jet is too big, try a smaller jet.
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