[nitestallker]

Hey all, new to forums, just bought a sweet 250j in stock config 43/14 I want to beef the acceleration up cause lets face it, where on Australian roads can you "legally" go faster than 120kms? Trying to make heads or tails of the best sprocket setup for low end torque, I want it to launch off the line an pull through the twisties don't really care too much about top end. Heard 45/15 an 43/15 is popular.. I weigh about 80 kilos, so come on boys an girls...what's your opinions?

 

[spooph]

Many people have found with the stock gearing of 45/14 that 1st gear is too short, and that gearing a little it taller allows the rider to use the torque in 1st gear a bit more effectively. I personally run 15/44 and am very happy with it! Once I get a bit more power out of the 250 I wouldn't mind going to 15/43, but I won't go any steeper than that. One thing I definitely wouldn't do is gear any shorter than 45/14, or you'll pretty much make 1st gear a crawler gear, or redline at 5mph. Pretty much useless for everyday riding. There is a guy on here who does a lot of touring on his bike, who runs 15/39, but I can't imagine how much the acceleration would suffer with that...

 

[slowride]

here are a few numbers I dug up from a chart.. 15-43 7,500 rpm 66.2 mph... 14-43.. 61.7mph 7,500rpm.. 15-39 7,500 rpm 68.1mph.. 15-45..63.2mph 7500rpm.. I run 15-43 myself and it works good.. I weigh 200lbs.. sorry I could not convert figures to metric.. Hope this gives you some idea.. All speeds are actual. not what your speedometer shows. As a rule of thumb they read about 4-5 faster than you are going. hope this helps

 

[Fry1024]

I weigh 200lbs..

Very close to 91 Kg

 

[nitestallker]

Thanks for the info fellas. Next question, whats the largest Tyre available for the rear? 150?

 

[slowride]

From what I've read, and seen. 150/60/17 seems to be the best choice for a larger tire. thats what they say anyhow. I found a good site for sprocket change data. speed, rpm,ect.. Gearcommander.com it works great ...

 

[spooph]

without modification, yes, I believe the 150/60/17 is the biggest tire you can fit on that rim and swing arm...