Author Topic: Timing Question  (Read 780 times)

Offline Duncan R

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Timing Question
« on: 23.09. 2010 17:55 »
My Shooting Star has an auto advance magneto fitted instead of the manual version. Should I set the timing as a standard A7 or Shooting Star spec?

Haynes manual states : Std A7 5/16" BTDC and Shooting Star 3/8" BTDC

Thanks

Duncan
Anglo - Indian A7SS (Actually is a 650)
Kawasaki ZZR 1100
BMW R80GS
BMW R1100GS

Online muskrat

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Re: Timing Question
« Reply #1 on: 23.09. 2010 20:53 »
G'day Duncan,
                       depends on your comp ratio and fuel used. I and others here have found that with unleaded fuel and reasonable comp (8.5-9.5) the timing needs to be retarded a few degrees. Try it at 3/8" but if it pings under load you will need to back it off until it stops pinging.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline Duncan R

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Re: Timing Question
« Reply #2 on: 24.09. 2010 09:11 »
Thanks Muskrat,

Motor is running nice at the moment, good starting and idling and seems to pull in any gear. I have not opened it much above 50 MPH due to the  weak front brake(which has now been sorted) Plug colour is good. Engine is a bit of an unknown quantaty, I don't know the piston spec. At the moment it is set at 3/8 BTDC and there does not appear to be any pinging. I think I will run it for awhile and see how it goes. I am hoping to attempt an engine overhaul over the winter which will include rebore and new pistons

Cheers
Anglo - Indian A7SS (Actually is a 650)
Kawasaki ZZR 1100
BMW R80GS
BMW R1100GS