i ran 14/43 on the road and christ it went up gears quick,but a little too quick for me,i was doing 4th gear roll on over takes because it could,i swapped the front to a 15 and it's still a beast going up gears (well as much of a beast a 400 can be) but it's a little better.

and as for speedo's being out ,yeah of course it will be but as long as you're not overtaking people at speed cameras what have you to worry about.

If you drop the front sprocket from 15 to 14 you will be doing 93% of what the speedo says.

Speedo reading of 50 you will be going 46.6.

regards
jon

Throwing a 14t front sprocket on makes a significant difference to acceleration over standard.

I used to run a a digital pushbike speedo so that it was always accurate even with changes to gearing.

How are you coming to that figure Jon? I want to fiddle with my gearing and so wanted to understand the calculation.

I got 46mph too, the maths I used was:

Actual gearing divided by standard gearing giving a gearing factor. Then divide the speedometer reading by the gearing factor to give the speed you should be travelling at?

=

2.857/2.666 = 1.071

50/1.071 = 46.6 mph which is equivalent to a speedometer calibration loss of 93% on any given speed assuming that the relationship is linear.

Hey all,

I recall reading something about gearing/sprocket config on Kermits NC30 rebuild on Honda Forums:

http://www.honda-forums.com/index.php?t ... &start=240
Some useful info on here and the link to the programme still works:

http://www.winsite.com/bin/Info?500000019820

According to Paul (on the Honda forum) the configurations came out as:

F / R
15 / 40 : 145.5mph
15 / 42 : 138.5mph
15 / 43 : 135.3mph (Will just about hit 60 in 1st, the rest down from here wont)
15 / 44 : 132.2mph
15 / 45 : 129.2mph

That is all based on being at the 14500 redline.

Maybe worth making a sticky of this

Incidently I'm after new chain and sprockets but how do you go about getting different combinations as I've only seen matched kits?

(Quote)
"Incidently I'm after new chain and sprockets but how do you go about getting different combinations as I've only seen matched kits?"

Just buy them separately Rick Oliver does 520 Talon sprockets in all sizes if you want to go down that route, 14/40 give a bit more zip and resonable top end.