Lowered Gearing ?

Hello, has anyone ever lowered the gearing on their Sporty?

I never go over 70-75 actually seldom over 60, so I do not need the high gearing for mean speed. And I was thinking that the gearing on my 1200S would be better if it were lower, so for instance, instead of riding round at 2000ish rpm in the streets, it'd be nearer 3000 and thus higher torque!

I can appreciate the fact that in a 30 or 40 zone you can stay in 2nd or 3rd cog, which is what Im doing now. But it'd be great to be able to use 4th for instance and have that 1000rpm range between say 2-3 thousand for more flexibility and less gearchanging.

Im presuming that a lower-amount of teeth on the front pulley would be sufficient to lower the overall gearing, but, being a belt drive, it's a new thing to me and may be more involved than chain, hence the query!

Malc.

[Tooty]

Hi Malc,

You didn't say what year your bike was, but cos it's a 1200S it must be later than 1998. I think the very easy solution is to fit the front pulley off an 883. The 883 front pulley is 27 teeth compared to 29 teeth for the 1200. This will lower the gearing approx 8%.
The part number for the 883 pulley is 40202-91B. Your 1200 belt will be OK as the rear wheel only needs to move 11mm to take up the slack of losing two teeth. You should be able to get a S/H pulley somewhere as people often gear up when they have 883s converted to 1200.
Just as a sweetener, 1200s with 883 gearing tend to want to lift the front wheel in 1st!

Tooty

Hi Tooty

She's a 2002, and that what youve said sounds very promising!
Im glad to hear it's not a big job, for though fairly competent on a spanner I certainly aint no genius!

Malc

[Alan B]

If you alter the gearing on the sporties your speedo will be out as they read of the fifth gear in the gearbox. When I changed my 883 to 1200 gearing the speedo was about 8% out. The gizmo to sort this out is about £100 from zodiac. Do a search on here for 883-1200 conversions. It's all in there.
Alan B

Oh, theres a small spanner in the works then!

Thanks for this info Alan, a question: Was the speedo optimistic or the otherway? Like an optimistic speedo reading 50 when I was really only doing 42 for instance wouldnt bother me, but the other way could be a problem re: speed cameras!

Malc.

edit, Ive just thought if it's the worst, a pushbike computer would solve it for about a tenner, theyre pretty accurate!

[Alan B]

Going from 883 gearing to 1200 gearing the speedo was shy of the mark. by about 8% so when I was reading 30 mph I was going at about 33-34 mph, so your way at 30 mph you will being at about 25-26 mph. No problem with speed cameras but that articulated lorry behind you won't be happy.
Alan B

Originally Posted by Alan B

No problem with speed cameras but that articulated lorry behind you won't be happy.
Alan B

That would be no surprise, Ive drove them things for a living between 1980 and 2004, and admittedly in that time I have met a few drivers that are bully's that need taking off the road, but the majority of the lads I worked with were A-OK!
Anyway, they know full well that on a single track 40mph is the HGV limit.