Hi, i run 11/42 sprockets on my 05 290 which suits me fine,i took the flywheel cover off to clean out, and found the chain had put a nice little groove in the clutch slave cylinder! I think i can remember 1 tooth front = 4 teeth on the back? So to stick with my current gearing i should run 10/38?As anybody tried this?. I have a Renthal chain fitted so possibly thicker side plates? Thanks

1 tooth on front = 2 teeth on rear not 4

Just do the math!

42/11= 3.81:1 ratio

38/10= 3.8 :1 ratio, or essentially the same. So you are correct that 1 tooth front is roughly equal to 4 on the rear.

Hi, Thanks for both answers,but both can,t be right? Copemechs maths sound right -not my strongest subject As anybody tried 10/38 gearing?

Thought this might of helped!

Sprocket ratio chart

Edited November 1, 200619 yr by Neo

Dale, not to sound like a butt or anything, but have you thought about just plugging a 10t front on there and going riding,,, should only cost you a bob, or a squid or whatever you guys use for money...

But seriously, front sproket is the cheapest part of that equation, go pick one up, pop it on, drop a link if needed (doubt it) and see how you like it..... You may find it is just fine.

And yes, not only does Mark make the finest cactus juice around, he can also divide (but I bet he used a new fangled calculator and not an abbicus)

Actually, when Al and I were kids, we had to use things called "pencil and paper"! And he still wonders why it takes me so long to do it! I cannot remember how to use a slide rule!

Thanks for all the replies - Alan - 10t is standard so i have got one availible to put back on - the reason i currently run 11/42 and thinking 10/38 [same?] is i found i never used 1st in sections and now so used to just clicking down dont want to change.Luckily i picked up the chain was fouling the clutch slave be fore any damage.Thanks