Hi All,
Has anybody out there experience with ignition timing for twin plug heads?
Series "D" Shadow, 1.3/16 inlets with 32mm MKI concentrics (200 main jets), MKII cams, 7.2:1 compresion (changing to 8:1 this winter), although putting a second plug in makes a farce of the theoretical compression ratios in my opinion, look at the amount of space between plug body and electrode insulator!!
I´ve run between 24° - 29° BTDC and not really felt a difference.
I´m running 29° BTDC (7° BTDC retarded) at the moment (because tickover is very solid) and it´ll do an indicated 110 slightly down hill and will pull 100 on the flat if i lay on the tank.
Can i expect much more?
I´m not a speed demon, i just want the bike to be giving its full potential
I know when i got the bike from my father with 9:1 pistons,MKIIs, 1.3/16 monoblocks and single plugs running at 34°BTDC, it´d pull an indicated 120 with me sitting upright?
is it all to do with compression ratios, or where am i going wrong?
Thanks
Has anybody out there experience with ignition timing for twin plug heads?
Series "D" Shadow, 1.3/16 inlets with 32mm MKI concentrics (200 main jets), MKII cams, 7.2:1 compresion (changing to 8:1 this winter), although putting a second plug in makes a farce of the theoretical compression ratios in my opinion, look at the amount of space between plug body and electrode insulator!!
I´ve run between 24° - 29° BTDC and not really felt a difference.
I´m running 29° BTDC (7° BTDC retarded) at the moment (because tickover is very solid) and it´ll do an indicated 110 slightly down hill and will pull 100 on the flat if i lay on the tank.
Can i expect much more?
I´m not a speed demon, i just want the bike to be giving its full potential
I know when i got the bike from my father with 9:1 pistons,MKIIs, 1.3/16 monoblocks and single plugs running at 34°BTDC, it´d pull an indicated 120 with me sitting upright?
is it all to do with compression ratios, or where am i going wrong?
Thanks
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