pacemaker gearbox

[garry inglis]

whats the best set up with the pacemaker box li150 at 4.9 is 16x46 the pacemaker is 5.65 how do I get it to 4.9 also I have the small tooth 3rd gear so if anybody has a spare larger tooth 3rd for sale I am debating fitting mugello 195 or rb 20

[Adam_Winstone]

The later (stronger) Pacemaker 3rd gear does not mesh with the earlier xmas tree (cluster) so buying a late loose 3rd will not help you.

[garry inglis]

thanks for that adam

[Adam_Winstone]

No problem, glad to help you avoid wasted expense.

I learnt this a number of years ago when I bought an early Pacemaker box and didn't count the teeth pre-purchase. It turned out that 3rd had been replace, probably as the result of breakage, with a 3rd from another box. I tried to fit a later 3rd but it wouldn't mesh correctly when assembled in the motor/ Unfortunately, the substitute loose gear resulted in there being a big ratio jump between gears (different no of teeth on the loose cog) so it meant that the ratios went from good to poor.

Adam

[Chris in Margate]

17th front sprocket and a new chain will give you 4.98:1 which will give you 10.2mph per 1000 rpm.
61 mph at 6000 rpm.

[garry inglis]

thanks chris 46.17 would that be an 82 chain

[garry inglis]

its ok ive just looked at the gear calculator its an 81 chain that will work ok thanks its abig jump from 5.65