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Bitsa (Ralph Wright - RIP):
Hi all,
I still have not got her right and do not really what to do next suggestions please.
Starts like a normal 750 full choke knock it off quick runs fine.Get it hot ticks over OK rev the engine idles nicely.The thing is I can not get the air screws out past 1/2 turn.If I turn them in one at a time it starts revving as Its riching up turn back out 1/2 turn idles nicely again but the plug colour is white,lean I think.I have checked float heights numerous times and can not get it any better.Should I try 42 slow jets, that's if I can find some?The motor is all stock including carbs jets etc.I would live with it but after reading topics here and elsewhere I am paranoid about the colour of the plugs.It seems no matter what I do I can not get it to run on the rich side.
Cheers
Bitsa

Waggles:
Tis easy to get paranoid isn't it? must admit I haven't even checked my plugs yet, I just set all jets as per manual, balanced and left it as it runs fine, might pull the plugs at the weekend and let you know what its like.

My first thoughts are:

Is the exhaust standard? are all the plugs the same? what model do you have?

Have you tried screwing the air screws in a bit, then as the revs rise, back off the throttle stop?

1/2 turn out doesn't sound quite right to me, you may have a slight blockage of the idle circuit. Do you have Hondaman's book? lotta good stuff in there about carb tuning / cleaning etc

Bitsa (Ralph Wright - RIP):
Hi Waggles,
Yes stock exhaust,plugs the same and she is a k4.If I turn the screws in yes I can slow her down with throttle stop but then all the screws would be fully closed.I have had them sonic cleaned and cleaned with carb cleaner several times no change.I do not have Honda mans book but have checked all topics that he has replied to on sister site and followed.
Bitsa

Seamus:
I guess you have a 341 exhaust on the bike. Have a look at the sealing of the exhaust to the head and also the inlet rubbers. If all the carb settings are correct, then I would suspect an air leak somewhere.

Also, check rubbers from filrter box to carbs. Is the air filter a standard one or an after market jobbie (K and N) that needs to be oiled?.

Hope that helps.

Good luck

Seamus

Another thought, does it have Kehin jets and needles? as the Keyster ones are reputed to produce erratic running

Bitsa (Ralph Wright - RIP):
Seamus.
You guessed right 341s needles and filter oems.I think its getting air from somewhere but after wasting 2 tins of various sprays can not find a f in thing.The tubes from box to carb new.All the stuff new is DS and no aftermarket crap.
Thanks
Bitsa

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