cheers skull... you know everything
i'll have to make a cuppa and chew that lot over a bit cos my head is hurting.
right !.....changing from a 16" rear wheel to a 18" rear wheel with standard 17T /34T sprockets gives a reduction of
approx 132 RPM @ 50Mph
and 165 RPM @ 60Mph
not a lot !.....
Whereas just changing the primary sprocket from 17T to 18T with standard 16" rear wheel gives a reduction of
approx 190 RPM @ 50Mph
and 228 RPM @ 60Mph
so definitely not worth changing the rear wheel to reduce revs .
Changing the rear sprocket from 34T standard to 30T with standard 16" rear wheel and standard 17T front sprocket gives a reduction of
approx 402 RPM at 50 Mph
and 483 RPM @ 60 Mph
So changing the rear sprocket only from standard 34T to a 30T is easiest and gives almost double the reduction in revs that changing to a 18T primary gear would give ! (bugga wish i'd done this study yesterday before i ordered a 18T sprocket )
changing both the front and rear sprockets to 18T and 30T would give a reduction in revs of
approx 570 RPM @ 50 Mph
and 684 PRM @ 60 Mph
However these changes according to XSJohn would require some changes to the bikes ignition timing and mixture etc or it would be undrivable.
I just thought that this might help some other owners ,like me, visualize the various options and rev reductions at typical highway cruising speeds without fitting overdrive gears. Hope I've got it correct ?
i'll have to make a cuppa and chew that lot over a bit cos my head is hurting.
right !.....changing from a 16" rear wheel to a 18" rear wheel with standard 17T /34T sprockets gives a reduction of
approx 132 RPM @ 50Mph
and 165 RPM @ 60Mph
not a lot !.....
Whereas just changing the primary sprocket from 17T to 18T with standard 16" rear wheel gives a reduction of
approx 190 RPM @ 50Mph
and 228 RPM @ 60Mph
so definitely not worth changing the rear wheel to reduce revs .
Changing the rear sprocket from 34T standard to 30T with standard 16" rear wheel and standard 17T front sprocket gives a reduction of
approx 402 RPM at 50 Mph
and 483 RPM @ 60 Mph
So changing the rear sprocket only from standard 34T to a 30T is easiest and gives almost double the reduction in revs that changing to a 18T primary gear would give ! (bugga wish i'd done this study yesterday before i ordered a 18T sprocket )
changing both the front and rear sprockets to 18T and 30T would give a reduction in revs of
approx 570 RPM @ 50 Mph
and 684 PRM @ 60 Mph
However these changes according to XSJohn would require some changes to the bikes ignition timing and mixture etc or it would be undrivable.
I just thought that this might help some other owners ,like me, visualize the various options and rev reductions at typical highway cruising speeds without fitting overdrive gears. Hope I've got it correct ?
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