Engine stalls when cold and under power

[superman]

So I'm having a bit of trouble with the old throttle in the mornings and I'm wondering if anyone has any ideas how to fix the problem.

The bike is carbureted so when I start it I usually put on a little choke and let it run for a couple of minutes before riding off. However whenever I twist the throttle to about 1/3 open it's almost as though the air/fuel mix is suddenly depleted and if I hold it in this position the bike usually stalls. After riding for about 20km I don't notice it anymore but it takes ages to go away.

You can feel it at any speed if you idle your throttle and then open it up that theirs a random gap in power.

Do I just need to go see a mechanic to get the bike tuned to sort this out? Carbs are clean looking from my last inspection of them.

[FJRider]

http://www.kiwibiker.co.nz/forums/showthread.php/148237-Bike-cuts-out-under-load

[p.dath]

If you are only having the problem in the mornings, then it is highly likely the engine just needs more warm up time. The tolerances in an engine are fairly fine, and different parts expand at different rates. Plus some fluids (like oil) change their parameters as they warm up.

Modern bikes have fuel injection which is programmed to work around this issue, but carburetters can not.

Try letting the bike warm up an extra minute - or just ride more gently for the first 10 minutes or so.

[Bassmatt]

If you are only having the problem in the mornings, then it is highly likely the engine just needs more warm up time. The tolerances in an engine are fairly fine, and different parts expand at different rates. Plus some fluids (like oil) change their parameters as they warm up.

Modern bikes have fuel injection which is programmed to work around this issue, but carburetters can not.

Try letting the bike warm up an extra minute - or just ride more gently for the first 10 minutes or so.

Yep. Wife had the same bike and the same problem, worse in winter for obvious reasons. Just let it warm up bit longer.