Final drive ratio

yo4hgx · Post by **yo4hgx** » Tue Apr 07, 2015 2:56 am

Hello lads,

Haven't used my exup for some years but within a month or so I will take it out for a spin around the mountains... with "melady", baggage and sh**t.

Problem is that before I used to be a lonely wolf and hunt around with some big guns but in order to keep up with them I had to dope my exup a bit: 127.5 main jets+K&N filter and 17/49(+2) sprockets. I love the way it pulls... but she is a bit thirsty on gas and I won't really need all the muscles now.

As is easier to toss it in and out, I was thinking to let the rear sprocket 49 (+2 from standard) but replace instead the front with 18 (+1 from standard) that will bring the final ratio almost back to the stock. I wonder if there is enough room for the bigger front sprocket or if any other problems that I can't thing of?...

Post by **Stig** » Tue Apr 07, 2015 7:44 am

Wow that will seriously slow down the acceleration

Btw stock is 17/47

I run 16/47 without any clearance issues on the swingsrm pivot and its not lost a lot of top end (not that it gets used that often with so many cameras around)

YAMAEXUP · Post by **YAMAEXUP** » Tue Apr 07, 2015 2:06 pm

I use -1 on front & rear sprockets as this puts the ration between -1 off the front only & standard. It accelerates slightly quicker & revs to the red line in top easier and does not overly affect fuel consumption like -1 off the front does.

Not sure if it's possible to fit a +1 front, but -3 off the back is almost the same as +1 on the front.

yo4hgx · Post by **yo4hgx** » Tue Apr 07, 2015 5:58 pm

So, stock is 17/47, now I have 17/49 and I wanted to keep the rear sprocket and replace only the front one which would result in a 18/49 combination with roughly the same ratio as stock.

It seems nobody went this road and the only way is to actually check it out.

Thanks anyway!