More problems

[DevonianScotsman]

This is becoming somewhat of a joke in the Jones household...

Once the engine is warm, if the engine is revved to more than 3,000rpm for any period of time - when i close the throttle the revs come down really slowly and sometimes stick at 3,000.

I've changed the diaphragms in both carbs, but this has made very little difference.

Any ideas?

 

[John Armstrong]

"Choke" is fully off?

 

[DevonianScotsman]

I think that's unlikely - the choke needs to be open almost fully to have any effect at all, so when it's closed it'll be doing nothing.

 

[Redboots]

I think that's unlikely - the choke needs to be open almost fully to have any effect at all, so when it's closed it'll be doing nothing.

Disconnect the choke cables at the carb and see if it fixes it.
Did you strip the carbs?... mix up the choke parts?...

Check for air leaks on the rubber tubes between the carb and head. Spray the area with brake cleaner and see if revs change.

Did you disconnect the vac hoses from the carbs and not replace?

John

 

[r100gser]

revs dropping slowly

first of all chck the cables are moving smoothley especially fron the spilitter under the tank,.check float levels, and carb sync, you may to adujst the stop screws and listen by ear if the revs drop quicker, do some fine adustment buy vac guages, but if it was mine i would check
valve clearences,first, especially exhaust,

 

[BillN]

Quite common - you just need to check everything and sort and problems and then it will come right

 

[judge]

Quite common - you just need to check everything and sort and problems and then it will come right

If they ever re-write the Haynes manuals you'll get my vote Bill

 

[Devon]

Rob, the bike is jinked
I'll do you a favour and take it off your hands

 

[Kenny]

Check valve clearances..then ensure you have 2mm free play where the cables sit in the carbs. Balance carbs and reset tickover...should cure it Also ensure throttle grip tube has not grease on it..needs to ( sort of ) snap instantly back..grease and other lubes stop this happening.

If all that fails, then try BillN theory above

 

[DevonianScotsman]

Cheers guys, I'll crack on with the checking of valve clearances and balancing the carbs etc - Then I'll let you know how I get on!

 

[Steptoe]

Back off the idle screws a turn each side, or until the idle is to your satisfaction . Then re-adjust the mixture screws under the carbs.

 

[DevonianScotsman]

Cheers Steptoe - I'll try that too.

 

[DrFarkoff]

Bob wieghts sticking in Bean can??? Ignition stays advanced until they free off then drop back
I just had a friends 80RT with the siebenrock do this, a few squirts of lube on the pivots via the little inspection window cured it

Also Check your Carb type against mixture screw setting in the haynes manual and make sure yours are set correctly

I chose the wrong carb on my 80RT and one was 3/4 turn out and the other was one and a half result high Idle

Good Luck and let us know what it was

 

[DevonianScotsman]

Hi Guys,

After a day f tinkering, it's finally sorted.
Here's what I did:

1. Changed the oil, fliters and sparkplugs.
2. Set the mixture screws to the CORRECT setting.
3. Got the trusty vacuum guages out and balances the carbs.
4. Checked and adjusted the valve clearances.

Personally I think it was the mixture screws.

Sorted in time for the Megaride!

Cheers for all your help!