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Bike Won't Idle

Featured Replies

Hi all,

 

I have a 2009 Sherco 290, but it doesn't like to tick over...

 

I have stripped the carb multiple times, cleaned out all jets etc.

I have adjusted the fuel mixture screw on the carb & played with the tick over screw.

I have checked the rubbers between carb & engine & airbox.  I have had all these off & even removed reed block to check petals etc. & replaced gasket.

I have replaced the crank seal behind the flywheel.

I have replaced the fuel tap and filter on the petrol tank, put new fuel in the tank and ensured the flow is good in to the carb.

 

Next step is to replace all seals / o-rings in the carb this evening, but after that I don't know where to look...the engine does sound a bit "poppy" and as if it is starved of fuel on tick over.  Also, the revs take time to die down....hence leading me to think there is an air leak.

 

It has a Dellorto carb...

 

Any other suggestions?

 

The bike was stood for a while last year before I bought it, but I have had it running fine for a couple of sessions...just now this issue has appeared...

 

Thank you,

 

James

 

 

 

 

 

Edited by jkendall

Start the engine and set the tick over screw to get it to run without the need to work the twist grip.

Get a can of WD40 or similar and spray it around the carb rubbers, joints et cetera and see if there is a change in revs when you spray in certain areas.

  • Author

Thanks, I did do this the other day and didn't notice any change, but to be honest...even on high tick over she doesn't like to keep running.

 

Could the timing cause this effect?  ...I did replace the stator the end of last year...

 

Thanks,

 

James

 

 

  • Author

Changed plug last night but no change. Hard to see spark in general but thats normal with these bikes....Going to retard timing a bit today as think it's quite far advanced. Will also check cdi etc. But think pins are pretty good as checked when fitted replacement stator last year.

Will let you know how it goes!

  • 4 years later...

Did you find the answer to this problem my bike cannot find a settled idle and will not rev at all had carb off cleaned twice new throttle slider also checked reeds they're fine put fresh fuel in how ever my fuel tap has a slight leak just noticed tonight cannot get a tight seal at the tap will that cause this problem

  • 2 weeks later...
On 4/3/2020 at 8:50 PM, Sanders said:

Did you find the answer to this problem my bike cannot find a settled idle and will not rev at all had carb off cleaned twice new throttle slider also checked reeds they're fine put fresh fuel in how ever my fuel tap has a slight leak just noticed tonight cannot get a tight seal at the tap will that cause this problem

Something as simple as a clogged or malfunctioning tank breather on the cap can stop a bike revving, as the tank will become vacuumed as the carb sucks fuel in, iv had it happen on other bikes. 

Just thought I'd update found the woodruff key had sheared ordered one today and hopefully we have revs I'll update soon as we fire it up 

Hi all replaced the woodruff key with one from splatshop also a new gasket for the fuel tap as this was leaking when turning fuel tap on new fuel line aswell still strange idle and no revs at all just borks any ideas/suggestions would be very appreciated dying to get out 

Crankcase (crankshaft) oil seals leaking allowing crankcase compression out and air in causing erratic or no idle and hesitance on initial engine revving/ acceleration. And as already mentioned weak ignition spark....possibly both faults likely..

Edited by section swept

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