Author Topic: Uneven running at very light throttle openings  (Read 654 times)

Offline bill harrison

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One of my A10's, a 1958 Super Rocket runs very well although I suspect runs a little rich as you can get rid of the choke straight after start up.  It also has an unpleasant on off feeling at light throttle.  None of my other bikes does this and I suspect that the mixture may be rich and as you lift the slide it suddenly picks up.  Can I fix this by adjusting the idle mixture?
Thanks.

Online Klaus

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Re: Uneven running at very light throttle openings
« Reply #1 on: 01.06. 2016 10:48 »
hi bill,

have a look at your airscrew, this is important for ticking over.
After lifting the throttle the cutaway does the venturi and needle position is in action.
A worn needlejet is caused if the bike run very rich if needle is in right position.

cheers Klaus


If you think, everything is under control, you are not fast enought.

BSA DB34 Goldstar, BSA A10 Road Rocked, BSA A7 Shooting Star, BSA M33, BSA M24, Kawa W650

Offline bill harrison

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Re: Uneven running at very light throttle openings
« Reply #2 on: 01.06. 2016 10:56 »
OK, I think it needs to screw out a bit to weaken the mixture at tickover.

Online muskrat

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Re: Uneven running at very light throttle openings
« Reply #3 on: 01.06. 2016 21:08 »
G'day Bill.
Once you get the air/pilot screw right for a nice idle it can then be adjusted about 1/8th turn either way to get a good lift. May have to reset idle screw again.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Offline bill harrison

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Re: Uneven running at very light throttle openings
« Reply #4 on: 02.06. 2016 08:30 »
OK, its shocking weather here I'll have to wait until I can get out!  I changed the voltage regulator yesterday for one of the new solid state ones but seems still not to be charging.  Looks like I'll have to make a day of it!

Online Triton Thrasher

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Re: Uneven running at very light throttle openings
« Reply #5 on: 02.06. 2016 15:37 »
Buy a new needle jet from Amal, unless you already have.