Low down fuelling on a 4JH / 3TJ hybrid

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plodder
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Low down fuelling on a 4JH / 3TJ hybrid

Post by plodder »

My hybrid lacks power and is snatchy below 4000 rpm. Not a problem except for pootling about town & manouvering. It's not something I normally do but if I can improve it then it is a bonus.

Is there any adjustment within the carbs that will help to smooth this out (without going to the dyno man). i.e. changine the idle adjustment screw, the idle jet or the needle position.
Evilchicken0
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Re: Low down fuelling on a 4JH / 3TJ hybrid

Post by Evilchicken0 »

have a look at the idle jets and see if they're clean ... is the throttle cable and linkage working properly ???
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cagiva996
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Re: Low down fuelling on a 4JH / 3TJ hybrid

Post by cagiva996 »

try this cv carb set up guide from factory pro ,i used this to set up my carbs.there is some good info here http://www.factorypro.com/tech/carbtun.html" onclick="window.open(this.href);return false;
plodder
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Re: Low down fuelling on a 4JH / 3TJ hybrid

Post by plodder »

The jets are OK and there's nothing wrong with the throttle actuation.

Thanks for the guide... I reckon it's a bit lean low down, so I'll up the fuel level by 1mm and see how it is.

Like I said, it's no drama.. it just starts proper pulling at 4K and goes nuts at 7K.

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