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Lag in acceleration

5009 Views 15 Replies 12 Participants Last post by  fitzy
I recently had my carbs cleaned, balanced and replaced new carbie boots. But when i had my carbs tuned by mike i realised that there is a bit of lag when i accelerate. The lag is dismissed if the revs are around the 3000 mark but other wise if i give the bike full throttle it stutters slightly (like as if it was started when its cold). Was wondering if anyone has any ideas how i can sort this out.

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had it replaced whilst i was at the service day. Might invest in a uni filter when this one gets dirty or if i can find a solution to the lag =/
a lag as in a plateau in acceleration?
I don't really understand if your saying if it is around 3k rpm, or everywhere but 3k.
it may just be a flat spot.
getting a uni filter will just make it run lean if you don't rejet your carbs.
yeh could say its a flat spot in a way it's like my bike has a massive turbo theres no power for a split second when i give it all then it comes around and takes off.
i'm going to have to give a response tomorrow i haven't slept in a long time i have on idea what im typing
usually theres nothing under 4k rpm anyway. if you are taking off or doing slow speed work itll need to be over 4k ive found
Is this lag experienced when you are changing gears by any chance?
I think what hes saying it that you've stopped, then you open the throttle, then the bike bogs down a bit or plays silly buggers, then suddenly hits its straps at 3000rpm and behaves as normal.

If thats the case I would be checking your carbs again. I had a similar problem withe the GPZ. If you dont have a fuel filter on your fuel line, nows the time to do it!
As above, Im guessing its not getting fuel through quick enough
How far open is your throttle when it occurs? This is more important than the revs. If the throttle is only partly open (below 1/4) it is your pilot jets the ones under the carbs. These are generally in a bit too much for emmissions purposes and the bike runs lean then when you open the throttle a bit it gets enough feul and takes off. You could try winding them out about half a turn to see if this helps, if it gets worse wind them in one full turn. this is because it is getting too much gas.

If it is 1/4 to 1/2 throttle it is generally needles. there is some overlap, but this is where you should start.

try chaning ur plugs bro...although u changed them at crutches...if wasnt running correctly afterwards so they could have fouled already...and its only like $16.00 out of ur pocket anyways!
What matt69 said, except its not 'pilot jets', its the mixture adjustment that he is referring to. Your bike sounds rich, and under rich conditions an engine will stutter or lag before gathering enough speed to be able to use the extra fuel without fouling or misfiring.

I would suggest a raising of the clips on your carburettor needles. This will have the effect of reducing the fuel metered to the engine for a given throttle setting, most notably in the midrange. You may also want to have a word to the fellow who adjusted the carbies, as surely he would have noticed this during a road test.

CHeers - boingk
check your tank is clean and fuel filter is okays, maybe you sucked some crap back down into carbies??

also as said change plugs mate
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