Bike sounding a bit rough and spluttery when idling fine when i open the throttle

any ideas of what could be causing it ??

also seems to be running a bit hotter than normal (or maybe it's just the hot weather makes it feel like that)

all fluid levels fine using 80:1 mix and never been a problem before

thanks in advance

Ali

Edited June 15, 201016 yr by High_Fiver

Cleaned the carb lately? Sounds like its due for one.

i'll give it a clean out

only done last month though

but worth a try

Strip n clean carb, put in a new spark plug, clean and replace air filter! Drain replace radiator with fresh coolant! Start up using fresh premixed fuel! That should ensure it runs smoothly!

Bike sounding a bit rough and spluttery when idling fine when i open the throttle

any ideas of what could be causing it ??

also seems to be running a bit hotter than normal (or maybe it's just the hot weather makes it feel like that)

all fluid levels fine using 80:1 mix and never been a problem before

thanks in advance

Ali

After adjusting the mixture screw, if it's still rough I'd look into:

water in fuel or stale fuel. We often store the bikes with a partial full fuel tank which presents two problems,

a larger surface area of fuel to allow "boiling off" or evaporation of the high-end aromatics that aid starting

and low-speed running and, a volume of air that presents condensation of water. This can be cumulative and

the results build on themselves to eventually cause symptoms. I like to store my bike in between rides

with a full tank.

Possible air leak. Usually this involves the manifold/reedcage area and most often is caused by over tightening

the manifold (the capscrews only go to about 7-8 ft lbs max) which causes the manifold to bow in between the

bolt holes.

a still obstructed pilot jet. At .35/.38mm, the pilot jet is extremely small and a piece of grit can easily lodge in

it. Most of us use fuel cans for years and dirt can accumulate in the bottom of the container so it's a good idea

to add an inline fuel filter. When using compressed air to clean jets or passageways in carbs, always force the

air in the opposite direction that the air of fuel flows as the orifices are usually funnel-shaped and this will prevent

the particle from staying lodged at the bottom of the "funnel".

Jon

Strip n clean carb, put in a new spark plug, clean and replace air filter! Drain replace radiator with fresh coolant! Start up using fresh premixed fuel! That should ensure it runs smoothly!

one more thing, check your fan is coming on? Maybe your thermostat!