front sprocket...how big can you go?

[drnick]

Hi,new to forum,have an '09' drz 400 sm,would like to change gearing for hway. driving...I would like to go up 1 tooth on counter shaft( I believe stock is 14) but a 15 looks like it would be tight,and chain would rub onto engine cases...I see on this forum some run 15's...for those that do,do you see any case wear,from chain rubbing? THX

[JoshV]

Driven makes a 16 stock is 15. With the 16 you have to file the chain gaurd just a little. It will be ok with the 16.

[Eddie O'Dell]

Some are saying they had to trim a little from the swing-arm rubber when using the 16.

[SMGranny]

The Driven 16 is what a lot use. Like mentioned above....15 is stock and when using th 16 you need to trim the chain guard and the swing arm rubber a little ....... The other way to go is go down to a 38 on the rear .... I have ran the 15/38 gearing and now went back to 15/41 (stock) as it seems to be the best all around gearing on the SM

[Eddie O'Dell]

I'm going to try the 16-44 combo just for the hell of it. The rear sprocket I'm using isnt made in less than a 44, but I love it.

[JoshV]

When I stuck my 16 on I did not trim the swing arm rubber. Just filed the countershaft chain gaurd a little. Remove the swing arm bolt and then you can slide the swing arm back a little. Once you get it on it will be ok. It is just trying to get it on.

[PBMW]

I'm going 16/38 when I get my motor done.
When mine was stock, I was 14/41. That was pretty buzzy. Wheelied good but it was buzzy. So I BB'd it with a 41, Hotcams and MRD. Geared it 15/41 and that was just fine. But it would pull hard all the way to the limiter. So, it would stand taller gears. It would still throttle wheelie in 3rd with 15/41.

[Eddie O'Dell]

I'm going 16/38 when I get my motor done.
When mine was stock, I was 14/41. That was pretty buzzy. Wheelied good but it was buzzy. So I BB'd it with a 41, Hotcams and MRD. Geared it 15/41 and that was just fine. But it would pull hard all the way to the limiter. So, it would stand taller gears. It would still throttle wheelie in 3rd with 15/41.

WOW Jim, the big 470 with 16/38 should go about 144.876 mph. Lets go to Bonneville..........

[PBMW]

Well, you know about them gearing calculators...
I doubt it'll go that fast but it ougt to have the power to do 120ish.
I ride with a bunch of liter bikes. They delite in leaving me when the road straightns out a bit. But then I beat em up in the twisties. I'd like to have a little more cruising speed.

[Eddie O'Dell]

Well, you know about them gearing calculators...
I doubt it'll go that fast but it ougt to have the power to do 120ish.
I ride with a bunch of liter bikes. They delite in leaving me when the road straightns out a bit. But then I beat em up in the twisties. I'd like to have a little more cruising speed.

Yeah I know them gearing calculators.......... I just threw the # out there and as soon as I hit send I thought the same thing, it did sound like a calculator #.......... I do wonder what class or record one could expect to compete in at Bonny though..............

[drnick]

Thanks guy's,OK 15 is stock,and it seems that you can fit a 16,but have there been any issues with chain rubbing up against the engine cases due to centrifugal force...it looks like there not much clearance between sprocket and case even with the stock 15. THX ED

[Lynk]

... I do wonder what class or record one could expect to compete in at Bonny though..............

Semi-streamlined, nothing less... I wouldn't want to try to set a speed record with those big air-dams.

[SMGranny]

Thanks guy's,OK 15 is stock,and it seems that you can fit a 16,but have there been any issues with chain rubbing up against the engine cases due to centrifugal force...it looks like there not much clearance between sprocket and case even with the stock 15. THX ED

If you leave the case saver on there you will be OK...you need to file that down though to get you clearence