Husqvarna 2009 TE 310 Workshop Manual page 142

ENGINE OVERHAULING
"Keihin" carburettor adjustment (TC 450-510; TXC 250-450-510)
Adjust the carburettor with warm engine and with the throttle in closed position.
Work as follows:
- Turn slow running adjusting screw (1) on the left side of the bike, , until the engine
is turning over at fairly high rpm (turn the screw clockwise to increase the rpm, and
anticlockwise to descrease the rpm).
- Turn adjusting screw (2) clockwise until the fully closed position is reached then
turn back 1,5 turns (250) or 2 turns (450-510).
- progressively loosen adjusting screw (1) to obtain the slow running required.
NOTE
An incorrect idle jet size could cause troubles of starting of the engine.
In this case:
- if turning the screw (2), no engine speed change is obtained, a smaller idle jet
TC-TXC
has to be installed;
- if the engine stops when the screw (2) is not yet completely turned, a larger idle
jet has to be installled.
After the idle jet replacement, repeat the "Carburetor adjustment".
Besides, if with a completely throttle grip open, poor acceleration or slow pickup
of the engine or sooty spark plug are obtained, it is necessary to check the wear
of these carburettor parts: throttle valve, metering pin and needle jet (mixture
enrichment). See the next pages.
G.22 Part. N. 8000 H0368 (09-2008)