Custom Rear Sprockets

Evenin all.

I'm trying to find a 44tooth rear sprocket for my poorly VFR and getting nowhere fast, standard being 43.

I dont want to make a radical change as I still do a fair amount of motorway work but figured +1 on the rear might be good for something.

I've tried the usual suspects - Renthal, Afam etc and nobody lists one for the Viffer anywhere.

Does anybody know any companies that could make one up?

1997 VFR750FV

Cheers in advance.

 

Funny you should ask that, there is a company that makes sprockets up...I saw the ad in the last day or soo..will have a look.

Here you go:
Custom sprockets

 

Cheers Ducky.

I was already looking at £43.00 for an alloy renthal...

 

You sir deserve a medal, but will have to make do with my eternal gratitude.

Ill get my existing sprocket sent over to them.

 

Front sprockets are cheaper

 

I know I know I was tempted but its the equivelent of plus 3 at the back and I'm thinking that may make it a bit revvy on longer journeys.

And petrol aint cheap..

 

so what are the gains of more or less teeth and sizes

 

Going down one at the front is the equivelent to going up 3 at the rear but not playing the same havoc with your chainline.

The above will give you more acceleration but will sit at higher revs than previously and drink more fuel / feel more buzzy - and reduce top speed a tad.

The reverse would be done if you were after top speed at the expense of acceleration.

Thats a REALLY simple way of putting it - can also depend on where bike makes it's power and other variables.

 

Per -1 on the front will give approx. 3.7mm offset rearwards. +1 rear will give 4.26 forwards. Depending on your chain condition and stock position you may need to adjust your chain length to compensate.

Lowering gearing (smaller front / larger rear) gives faster acceleration at the expense of top speed, not a concern for most bikes. Whether you mind the circa 100rpm difference (based on +1 rear) is up to you.

Raising the gearing will have the opposite effect.

On 600cc 4cylinder bikes this is a common mod to allow easier riding in town, as they make their power later in the rev range a few 100 rpm higher is advantageous.

-1 front = +3 rear is about right. Although the fuel consumption thing is totally subjective and also marginal at best.

Stock gearing on your bike will give 80mph in 6th at about 5300rpm, with -1 front you'll hit 80 in top @ about 5900.

+1 rear on a 4cylinder will be a placebo effect at best, imo. It's not enough of a percentile adjustment to the rpm distribution to make a difference. On your bike, it's a 2.3% difference.

http://www.gearingcommander.com/

 

B.&C Express will make what you want. Steel are cheaper than alloy

 

dave your amazing,,, reading that is like a fucking manual mate

 

Cheers for that Skortchio and I take your point. Some explanation you've given. I'm now back where I was at the start of my post...

 

Basically mate, +1 on the back is no use. +2 or +3 will improve accel, but lower mpg. You can,t have both. You may also need a longer chain , but doubtful. One less on front is cheapest and most effective, but speedo will be out, front or back.

 

That! Speedo will be out approx 1.1% per rear tooth, but it's already around 10% off from the factory. Lowering gearing makes it over read so you'll not be caught out going faster than you thought you were.

The mpg is really tiny and you'll probably not notice it unless you start going crazy on the gearing.

 

Hmmm...+2 rear or minus 1 front and go for broke....

 

It's really not a savage difference I promise you. -1 front will be about 300rpm difference across the rev range with noticibly smoother low speed riding.
Plus a front sprocket is only about £9.

Make sure you've got 4mm of rearward movement in your axle adjuster and you're all set.

 

Here's a site that calculates the effects.

http://www.gearingcommander.com/

 

Look at the bottom of my post.

 

I Droped a Totl Last week - Still have to Go to Dentist ...lol - i droped one on front of Mine Helps Whelle as Well

 

-1 ordered. I will await the bike wheelying through 2nd and 3rd gear on the power and single figure fuel economy...