Running rich?

[therefused]

I think my bike mite be running rich?

Problems are, when started it idles fine, but bogs abit at 4k, fine after i have gone down the road. after its warmed up it idles at 2.5-3k.

When i let the throttle off it almost always backfires.

Finaly, it sometimes cuts out when its wet/raining, just like its run out of petrol, its hard start after, but once its started i have to hold the revs at about 3k for 5mins then its fine, if i try rev it past 3k before 5mins it bogs and cuts out again.

Rim of the endcan is also jet black in burnt oil/petrol, nt sure which one

Any ideas?

[Neosophist]

I recommend you strip and overhaul the carbs.

Your bad mix could be blocked jets. Once you've given the carbs a once over and made sure everything is as it should be go from there.

Backfires (check exhaust system for leaks after you've checked carbs)

[therefused]

Will a leaking exhaust cause any other problems apart from backfireing?

Also in regards to carb pilot screws, is clockwise/screw in making the carb leaner or richer?

[Cammo]

Also in regards to carb pilot screws, is clockwise/screw in making the carb leaner or richer?

Screwing them in is a leaner setting, out is richer.

[griff488]

If you screw the pilot screw all the way in how many turns out should it be for the right mixture?

Cheers Griff

[The Hamster]

Griff- between 2 and 2.5 turns out from fully in is usually where the bikes run nicely. I would go for 2.25 to start and just tweek them a bit if you feel the need.

[griff488]

Cheers mate!
I have the same problem as therefused. Runs lovely on tickover, bogs down around 4-5k then ticks over at 2.5/3k revs! No back firing though! You can smell it running rich so will have a fiddle when i get chance! If not looks like another set of carbs to clean! Just done the missus' gixer!!
Are there carb rebuild kits easily available for these carbs? I used NRP carbs for the gixer ones!

Cheers Griff

[Neosophist]

you can get float bowl seals if you need them, i only change them when they leak rather than a matter of course as there a rubber band rather than a gasket.

Other parts like floatpins etc are available but costly.

Maintaince is easy on them but fiddly getting them in and out due to the V of the engine.

[therefused]

Checked my needles and they have a washer, if the mod has been done they will have 2 washers am i correct?

[Neosophist]

Checked my needles and they have a washer, if the mod has been done they will have 2 washers am i correct?

Check the size of the washer.

It could have 5 ultra thin washers, or 1 thicker washer :D

:)