www.zxrworld.co.uk

I was at Cadwell at the weekend and after each race the engine sounded right dodgy - almost like it was running on 2 or 3 cylinders. It would be worst under about 10k revs (on the in lap) and better above that. Off the circuit on the way to park it up after race 1, it stalled, but restarted first attempt.

I raced last year and can remember the engine sounding odd on cooldown, but it had never stalled before. Someone trackside suggested I shouldn't worry, that it was the carbs rebalancing. I'm happy to go with that, as it starts up and runs fine by the next race each time, but would like to hear views here too.

I am running lower idling revs at the minute (c. 2k) versus c. 3.5k last year - not sure if that is why it never stalled last year.

Glad to hear your views, and also a layman's description of what carb rebalancing actually means would be good (assume I know nothing - you'll be very close to right ).

Cheers

Gerhard

anyone?

Here is a guide to balancing carbs - http://www.zxrworld.co.uk/zxr400/balancing.html

Have a read through it to understand what it entails. If I was you I would go back to your original set up. If the problem goes away you know its a fueling issue. If not then my next step would be balancing the carbs. Come back to us and let us know how it goes.

while running flat out the carbs stay cool because they are busy giving up latent heat to the fuel atomisation process going on inside them (this is what causes carb icing in winter), on the in lap, the carbs start to soak up the heat from the engine which throws the mixture out the window till things have settled down. The actual effect this has depends on your individual setup..

i wouldnt worry about it.

thanks chaps.

Hi,
I had this very problem, discovered the fuel pump had given up. It ran perfect then would stall or run lumpy after a race.
Put on a new fuel pump and the bike has been perfect since