PWK 28 Idle Problems

[headcoats]

Over the years I have taken these carbs apart so many times I can do it with my knob 🍌
But have a problem now I can't seem to fix
Idle is fluctuating but as soon as you give it a sniff of throttle it pick up OK.

The other thing is as you shut throttle, instead of just burbling it starts to buck about and snatch.
Thinking now could it be electrical and what processes could I do to nail the problem

[shaunthe2nd]

Is throttle cable lubricated and routed without kinks or nips?

[shaunthe2nd]

First time on this site I've used lubricated, kinks and nips in the same sentence without a moderator warning!

[abar121]

Can you isolate it to one cylinder or is it both?

[headcoats]

Think it's the left cylinder but will look again tomorrow.


It has Lomas GP style pipes so end cans are piggy backed



Jetting and settings have remained the same since engine was built and over 500 miles now and was running OK at those RPM'S before

[oldbritguy]

Did you get to the bottom of this?

I have a set ofPWKs to fit to the 421 and trying to pre empt possible snags.

John

[headcoats]

Think it was a blockage in the airscrew jet block, not the pilot jets.
You take the 2 security screws out to remove jet block and it reveals tiny little holes