small block virgin

[YAMLAM]

I`d go with what you got, nothing wrong with Li125 box , use a 16 tooth front as suggested.

[wurzel]

Thanks for the advice gents, much appreciated

[corrado]

Li 125 box has 5.65 final drive with 15 x 46 std sprockets. To reach 60mph you'd have to be revving it to 6700 rpm, on a dyno in 3rd gear maybe but on the road with a heavy rider, in your dreams. You need 5600 rpm just to get to 50.
With a 16 tooth front sprocket 60mph would come up [again in theory] at 6300 rpm, and 50mph around 5250 rpm.
Given that a reasonable cruising rpm for this set up would be around 5,000 rpm that equates to 45 mph with 15 x 46 and 48mph with 16 x 46.
In the real world lots of other factors contribute to not being able to match those numbers on the road.

[corrado]

It'll go much faster with an Indian speedo though.

[Bilko]

It'll go much faster with an Indian speedo though.

[shocky]

Id spend £150 on getting the cases converted to 200 and an indian stg4 200 kit which are preety well proven and a 30mm carb and decent pipe can give very good figures