I tried doing a search but cant seem to find an answer..What kind of diff ratios work with bec's?..What are some common examples?

My car is a fireblade seven with 15 " wheels. I changed diff from 3.62 to 3.38 which is much better. I think for road use you might consider a 3.14 but I'm not sure.

3.38 is best if you can get it, Sierra deisels have this I think but not LSD.

Most people seem to use a 3.62 LSD though.

HTH,
Rich.

in my limited knowledge and reading, the 2.3 diesel sierra has a 3.14 open diff, and 2 litre autos have a 3.38, again open. I may be wrong but 3.14 definately exists.

a 2.3 diesel sold on ebay the other day for £120, including a spare engine (whoopie!)... cheap if you really need the long diff.

edit: the general consensus is that the 3.62 is no good for long motorway trips, though it depends on the engine.

[Edited on 11/7/04 by JoelP]

Depends on what engine you are using, and what wheels and tyres. ZX9's need a much higher ratio than say a busa or blade. I run a zx9 with 15" wheels and a 3.54, and it still tops out around 112mph.

I have a spreadsheet for bike engines, u2u me your email address and I'll send it to you.

Also depends if you are going live axle or IRS as to what is available.

I ran 3;89 on 15" wheels with a blade motor, maybe why i dint mind long hauls n motorways..............

i ran a 3.62 on 17" wheels with the R1 motor ,it was ok up to about 110 but after that it crawled up to 125,this time im using 15" wheels with a 3.62 and the hayabusa engine,it might rev out but i also dont mind the high revs on long hauls but if i could find a 3.38 diff i would be using that instead

[Edited on 11/7/04 by OX]

I am using 185/60 14s (the same overall diameter as 195/50 15s) and may go down to 185/55 14s or 195/45s as according to chris' bike-ratio spredsheet with a 3.62 LSD diff I will still get 140mph topspeed.

Adam

I run a 3.14 with Hayabusa and on my 215-40 15" ABC10's my top speed is about 127 mph (10,500 rpm), which I now know the car will reach

I plan on using 225-50 15" tyres on the rear so the top speed will increase to 140 mph, but I doubt the car will manage that without a downhill run with the wind behind me. Not sure I fancy going that fast in it anyway

With a 3.38 and 225/50 15" tyres the top speed would be about 130mph which is probably about right.

Because the gixer 1100 engine is such a torquey engine (for a motorbike) they could afford to put in a very high 5th gear (0.913 when A ZX9 is 1.035 in 6th). This is why it varies with different bike engines.

Adam

Dont forget that each engine has a different primary reduction ratio (the ratio between the crank speed and the clutch speed), so you have to take that into account when looking at overall gearing and not just compare the actual ratios in each gear.

cheers
Chris