justin.fiveash
New Member
My bike was running great with the stock carb. I received a performance carb in mail and changed it out. Now it's running like ****. Any advise?
Lost a lot of power
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butre
Well-Known Member
performance carbs are a supporting mod, not a bolt on for stock engines. you need a better exhaust flow and probably a better intake flow to make any use of the thing
D
Deleted member 12676
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make sure the float is even with the carbs horizontal when just closing the input needle.
too low and the bike runs too lean at idle. too rich and it runs too rich at idle.
too lean or rich may mean it won't start at all.
Once you get it idling then you have to adjust the needle height for clean running at middle RPM and then adjust the main jet size for clean running at top RPM. That is true of all carburetors, not just yours.
too low and the bike runs too lean at idle. too rich and it runs too rich at idle.
too lean or rich may mean it won't start at all.
Once you get it idling then you have to adjust the needle height for clean running at middle RPM and then adjust the main jet size for clean running at top RPM. That is true of all carburetors, not just yours.
Fabian
Well-Known Member
The standard NT carburettor (when jetted correctly) works as well as any of the "so called" performance carburettors.
The only meaningful improvement over a float style carburettor is a Walbro style diaphragm carburettor, though for the same venturi size it will not make any more power, because the laws of physics dictate how much air can be moved through a given internal venturi diameter.
The only meaningful improvement over a float style carburettor is a Walbro style diaphragm carburettor, though for the same venturi size it will not make any more power, because the laws of physics dictate how much air can be moved through a given internal venturi diameter.
justin.fiveash
New Member
Yup. I put the NT back on and jetted it. Took about 5 hrs to get it right, but I finally got it. I love this bike!
Fabian
Well-Known Member
I agree.
A properly jetted standard NT carburettor is surprisingly reliable and works surprisingly well.
Fabian
Well-Known Member
The only thing better than the standard setup is a Walbro style diaphragm carburettor; allowing ease of tuning when compared to a float style carburettor, such as the NT.
The Wabro has external Hi and Low jetting screws so there is no mess as compared to the standard float carburettor; requiring the fuel bowl to be removed 30 times to change main jet sizes when optimising the air/fuel ratio.
Once you have installed a diaphragm carburettor (with thermal isolation spacers) you will never go back to a float style carburettor, not just for the ease of jetting but for the fact that they don't suffer air or fuel leaks.
HeadSmess
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i been thinking of making a separate bowl for the NT... with a nice simple adjustable main jet hooked up to the existing straw via a hose 
it will be necessary when i actually finish this dyno stand...
whaaaa? they do it on lil outboard engines, mine even has adjustable high AND low!
theres one performance carb out there, the "red filter" one...only difference i can see between it and the stock NT is that it has a fuel tap? of course, it isnt the only "performance" carb out there.
everyone is agreed. stick to the NT or nitto, depending which label you choose to look at?
it will be necessary when i actually finish this dyno stand...
whaaaa? they do it on lil outboard engines, mine even has adjustable high AND low!
theres one performance carb out there, the "red filter" one...only difference i can see between it and the stock NT is that it has a fuel tap? of course, it isnt the only "performance" carb out there.
everyone is agreed. stick to the NT
or nitto, depending which label you choose to look at?
