Popping through Carbs

[metalforever]

Right the UK GS problems continue

I've recently adjusted my carb after having trouble with the cylinders fouling plugs.

Now that that seems ok when the bike runs (and it runs poorly at that!) it's popping through both carbs. my initial thought was valve timing but i've checked this and its correct

So what else could it be?

[The Buddha]

If it pops too much, you can blow the slides out ... and yes that will only cause more popping.
I dunno, clean and jet it ... what ever is right for your setup ... you have to put more details on here ... maybe fuel quality has crapped out and caused these to get worse and worse.
Cool.
Buddha.

[metalforever]

Right well here's exactly what it's doing now.

As it's a UK spec bike im running stock jetting (120 mains etc) and 2.25turns out on the mixture screw.

So that says it's not the carb's fault causing the problems, especially since ive replaced every part of the carb except the float seat and valve which ar eon order.

What happens is the bike finds it very hard to start and when it finally does it wont idle as it can't maintain any revs without choke/throttle (Full choke makes it sit at less than 2k revs)

When i rev the bike it pops every 4-8 seconds or so, if i try to hold it at any fixed revs the revs gradually drop and the bike stalls, meaning i have to continue to add throttle to maintain the same revs.

I've checked the plugs and they appear to be sparking nicely.

What i'm thinking it is is valve timing as i think this is happening:

Fuel Air Mixture Prep'd in Carb > Inlet Valve Opens > Inlet Closes > Ignition occurs > Exhaust Opens

Once the exhaust opens i'm not sure what happens. it could be on of the following two in my opinion:

Exhaust Opens > Exhaust Closes (Too early) > Inlet Opens > Pressurised Exhaust Gases exit through carb

OR

Exhaust Opens > Exhaust Closes > Inlet Opens > Ignition Occurs > Poor Inlet Seal allows burnt fuel air mixture to escape through inlet into the carb

Any ideas?

[The Buddha]

How does it run once warmed up.
If it runs fine ...
Its a tight valve. Possibly an intake.
If not, its a vacuum leak on the intake side or just plain old bad carbs.
120 is too lean to run right ... and 2.25 also, I set to 3 on that and 125 mains and 40 pilots.
Cool.
Buddha.

[metalforever]

Buddha

120 and 2.25 turns is standard for a uk spec bike...

however i was running 3 turns out and it was far too rich. im going to try 2.5 turns to see if that helps my problem if not it's going to the garage/ebay!