Little rev then dead, very confused...

[bikemonkey]

Just got my bike back running again, and when I was burping the cooling system I noticed that it struggled to idle after a rev to about 3k then often dies after a rev to 6k.

I also checked the electrical system and the strange thing was that when I unplugged the reg/rec plug the revs rose 500rpm then dropped the same when plugged back in, but the outputs of the plug are all good.

It also won't start after dying without a little throttle and an adjustment of the idle......

Video here of what I mean.


http://s1126.photobucket.com/albums/l60 ... G_0457.mp4

[CMSMJ1]

NO fuel..??

[bikemonkey]

Should be getting fuel, full tank, vacuum working properly, had been running for a while before I noticed it.

It is on the abba stand atm, but that's never caused problems before....

[Morespeedvicar]

Bet the idle jets have got bunged up, the revs will pick up with the reg unplugged takes the load off the genny.
It may clean up with use but i'd be more inclined to say the carbs are gonna have to come off.
how longs it been stood?
Cheers
Ian

[bikemonkey]

I've just put new pilot and main jets in the carbs, so I doubt it's that...

[CMSMJ1]

Hows about - does it run on choke? is the idle adjuster all sorted?

Seems a bit abrupt in the vid..

[bikemonkey]

Runs on choke fine, idle adjuster is in properly and set at 1600rpm.

Took it off the stand, seemed a little better but it still cut out.

So I upped the idle to 2k and it struggled a tiny bit but didn't die.

Think I'm gonna stick the bodywork back on and take it for a good run, see if it just needs a little flushing through as it were.

[Neosophist]

Interesting.

You've been messing with the carbs right?

The pilot circuit isnt the same as the pilot jets, it's the three small holes that you can see from the engine side of the butterflies, very easy to gum up.

To me, providing you have fuel in the bike (always check the obvious first) it seems like the idle circuit is wrong and its cutting out becuase of it.

Do you have any air-leaks? Did you mess with the float heights / pilot screws?

[bikemonkey]

Didn't touch the float heights, adjusted the pilot screws to 2.25 turns out.

No air leaks, carb's are seating properly and all tightened up.

They were very clean inside to me...

[Neosophist]

Didn't touch the float heights, adjusted the pilot screws to 2.25 turns out.

No air leaks, carb's are seating properly and all tightened up.

They were very clean inside to me...

How was it running before you messed with it? Tried putting the pilot screws back in a little?