Erratic tickover

[Windmill John]

Hi All,
Didn't put this in Workshop as unsure whether fuel or electrics, but....

Sometimes, most times when you rev the bike and let go, it goes to about 2000 rpm
Sometimes it drops down, but sometimes it doesn't, or can drop down to idle but can take a little while.

Okay, just pre-empting some questions.
Carb stripped, cleaned
New diaphragm; irrelevant for idle.
Cables adjusted
Slide height adjusted
Left and right bodies synced
Float height adjusted; hopefully correct...
Inline filters removed
Looks like recently purchased carb to inlet rubbers; although I haven't yet sprayed over them to test, but they look good.
Air filter oiled and checked.

Are there any electrical possibilities to an erratic idle?

Cheers

John

[xtzrick]

Can't think of any electrical probs that would cause erratic idle, it is more likely to be an air leak.

Have you checked the butterfly spindle on the right carb for wear?
Apparently they can wear which could cause an air leak.

Rick

[Mezo]

So you removed & checked this filter behind the float needle valve?



Mezo.

[Mezo]

Also have you checked your inlet rubber boots for air leaks, and is your rubber pipe from the left intake to your fuel pump OK (no cracks) your pump works by vacuum.

Mezo.

[Windmill John]

Thanks for that. Yes I check needle valve, eveything in carbs fully removed, checked, sprayed, blown etc.
Inlet rubbers look new and I greased the two o rings; I'll try spraying brake cleaner later whilst running.
I'll try spraying that linkage too.

Didn't check the hose to the pump, but will do.

Tappets set correctly by the way.

Thanks again.

John

[jibber]

Is the throttle tube or grip binding in any way on the bars?

[Windmill John]

Okay, just sprayed around the inlets, hoses, carbs, garden, cat..... No increase in revs!!

It didn't Rev and stay at 2000 until warm and then not everytime!!

I'll monitor and see how it goes.

Jibber, I made sure I cranked the throttle closed to test, no difference. It is certainly not as bad as it was on the ride from the previous owner, but then again, that was 90 miles, not 5.

Let's not worry about the fact I started to kick start it, but was met with a feeling like I was kicking through treacle and a ratchety sound; at least the electric start is good

Just stuck a new picture of Jean Claude on my website.

[xtzrick]

Try to work out if it's happening when you close the throttle from large or small throttle movement, is the right carb being used when you shut off?

Found this

phpBB [video]

No idea if it's relevant to your problem (I don't speak Welsh... or the language in the vid either )
Just thought it was worth a link to the forum

Rick

[Windmill John]

Spaseeba Rick

I want to get a bit of riding in now before getting carbs off again. I'll monitor how much throttle etc.

Cheers

John

[Windmill John]

Thanks xtrider. I fitted a new diaphragm and slide when I stripped the carbs. It is certainly much better than when I bought the bike.
I'm going to live with it until I take the engine out for some checking, helicoiling, leak stopping etc.