StromTrooper banner

Changing sprockets

21K views 37 replies 28 participants last post by  D.T.  
#1 ·
I am considering putting a smaller rear sprocket on my 2012 Adventure to reduce engine rpm. I get 62-64 mpg if I keep the rpm's below 4500 when cruising (so below 65 mph indicated, probably about 60 mph actual). I just returned from a 2200 mile trip where I averaged only 50 mpg. In part becasue I was carrying extra weight, but also because I was cruising on the highway in the 5000-6000 rpm range.

Has anybody done a sprocket swap? Any advice on size or pros/cons?
 
#2 ·
From what I have read in this forum, gearing our bikes up (usually by going up 1 tooth on the CS sprocket) did not help fuel economy -and in fact, it may hurt it slightly.
I have found that the motors on our bikes are surprisingly "Happy" at sustained highway revs (or higher).
 
#3 ·
This topic has been discussed to death here... There are many threads on this (you can search if you like)... But the gist is increasing your gearing probably won't increase fuel economy (it's pretty much overgeared now)... But if you must increase your gearing I suggest a larger front sprocket... It's cheaper and affects chain slack (or lack thereof) much less...
 
#4 ·
A one tooth change on the front sprocket is equal to about a three tooth change on the rear. That much change on the rear usually requires changing the length of the chain. Try a 16 tooth front sprocket and see how you like it...many like it for the rpm reduction on the highway. Plus, the front costs less. And, yes, there aren't any reports of saving gas, much less saving enough gas to pay for the new sprocket. The increase in drag at higher speeds is equal to the square of the velocity. Double your speed and you have four times the drag from the air. Changing your speed from 60 mph to 80 mph is about 77% more drag (I know, I probably got the math wrong, but the concept is right).
 
#5 ·
I also would recommend going up a tooth on the cs sprocket. Besides the benefits described in other posts, your speedo will be much more accurate. When I went up to a 16-tooth sprocket on my '13 Adventure, the speedo became almost perfectly on per my GPS. The odometer became about 4% slow though.
 
#8 ·
I may go to a 16 tooth front sprocket soon just to see how I like it. Anyone thought of going to a 530 chain? Is the chain “channel” wide enough to take a 530 chain? Is this too much overkill? Just wondering. I had a 530 on my Bandit which has admittedly a lot more HP. It’s a massive chain and very sturdy. I heard the RK chains had a recall a while back on the 2012 DL650s. I have a RK on mine as opposed to a DID and wonder if it’s OK. I’ll Google this one.
 
#32 ·
This.
MPG and fuel "efficiency" are two different things. At lower rpm the rear wheel won't be putting as much horsepower to the ground, also the engine breathes better and is in better "harmonic balance" at higher rpms.
 
#10 ·
My engine is quite happy cruising at 5500+. I find many bikes are geared tall. One less tooth on the front sprocket works best for my bike and for the riding/roads I explore.
 
#12 ·
A 530 chain and sprockets is overkill on the 650. Is is added cost and weight for little benefit. On a 1000 it does give longer life. There is a slight performance hit with the heavier chain.
 
#14 ·
Hope this is correct. Looked this up and found the 2012/13 WEE has stock:
15t - front
47t - rear
and a 118 link 525 chain
Those are accurate.
 
#16 ·
Staying on topic and no hijack intended, but if one was to change the front sprocket up or down a tooth, what brand is recommended? I am assuming SV Racing has something in their product line but looks like they like to sell the sprocket as part of a kit including chain. Wanting to put an order together to include a front 14T sprocket, also bar risers. Any suggestions would be appreciated.
 
#17 ·
People say that a (year?) GSX-R 600 sprocket has the OEM rubber/plastic "noise-ring". Others will not have it. I do not know what sizes the GSX-R sprockets come in, but seeing that it is a bike commonly used for racing, I would suspect that there are plenty of OEM gearing options.
 
#18 ·
Here's the P/N for the GSX-R 600 16T OEM Sprocket: 27510-20A10. I am using one. $41 delivered at one place I checked.

All these use the 27510-20A10:

1996 GSX-R750X TRANSMISSION
1997 GSX-R600 TRANSMISSION
1997 GSX-R750X TRANSMISSION
1998 GSX-R600 TRANSMISSION
1998 GSX-R750X TRANSMISSION
1999 GSX-R600 TRANSMISSION
1999 GSX-R750X TRANSMISSION
2000 GSX-R600 TRANSMISSION
2001 GSX-R600 TRANSMISSION
2001 GSX-R600Z TRANSMISSION
2002 GSX-R600 TRANSMISSION
2002 GSX-R600Z TRANSMISSION
2003 GSX-R600 TRANSMISSION
2003 GSX-R600Z TRANSMISSION
2004 GSX-R600 TRANSMISSION
2005 GSX-R600 TRANSMISSION
2006 GSX-R600 TRANSMISSION
2007 GSX-R600 TRANSMISSION
2008 GSX-R600 TRANSMISSION
2009 GSX-R600 TRANSMISSION
2011 GSX-R600L1 TRANSMISSION
2012 GSX-R600L2 TRANSMISSION
 
#20 ·
I've been thinking about changing gear ratios as well, and I haven't been able to find much on changing the rear sprocket. Seems like this is WAY easier than changing the front, still pretty affordable. I don't have air tools to break loose the bolt holding the CS sprocket and the jump from 15t to 16t is a little steep for me.

I'd like to get the 45t for the rear, which would be a 4.3% difference, which effectively splits the difference for the speedo/odo accuracy. Gearingcommander.com calculates that I'll need to lengthen the drivetrain up 0.34 inches. Is there space for this on the Glee?
 
#23 ·
13 would be too small radius, so 17 is next. 53 or 59 rear?
 
#22 ·
I put a $25 16 tooth Sunstar front sprocket on my 2013 V-Strom and it's great. I feel like I can make better use of the low to mid power band compared to the stock gearing. I'm not bothered by the slight increase in chain noise, it merely sounds like a dirt bike's chain now.

I used an impact driver to remove the 32mm nut. The job took about an hour at a leisurely pace. I'm very happy with the results.
 
#24 ·
Just an update on this- I changed out my REAR sprocket for a 45t- picked it up used (wear marks on bolt holes only) for $15!

Install was crazy easy- I'm seriously surprised more people don't go for the rear change than the front- the front seems very complicated and difficult. The rear took 10 mins and two tools.

I really like it- I can't tell the difference in engine handling. It brought my speedo up to within 2MPH- 60mph indicated is a true 58, so it's close enough for me. Bottom line, I'd highly recommend changing out the rear to a 45T if anybody wants to correct speedo a little, bring down RPM a little on highway, but not lose too much bottom end- it's a good compromise.
 
#25 ·
rear sprocket-can i turn it over? DL 650 2013

Hi, Is it a good idea to turn over the rear sprocket to extend its life? I notice it is not identical on both sides so may need to pack out with some washers if turning it over to the 'non-standard' side to keep its alignment with the front sprocket. Only maybe a miilimeter or so. Or am I being too fussy and should I not worry too much about keeping perfect alignment? thanks, Peter (N.Z)
 
#26 ·
#30 ·
I went the other direction and switched to a 15T:48T vs OEM 15T:47T. Kind of wished I could have found a 49T (OEM chain length could have handled it). I've seen others on KLRs that go too tall (only 5-speed tranny) to make believe they have highway gearing. When carrying a lot of gear / hill / headwind / trying to go 65-70 mph, they would need to downshift sooner / more often than me running 1 tooth more on the rear. 4th gear on the KLR is more "buzzy" and not where you want to be long term.

I'm sure that the V-S 650 torque curve / characteristics are different and they may tolerate higher gearing better than the KLR but I take mine on off-road shortcuts on most local rides / longer trips. It is a lot of motorcycle to pick up by yourself if I do the "stall & fall". Give me rpms!
 
#33 ·
I had an experience where I wish I had lower gearing, not higher. Riding two-up on a mountain road with some real steep sections and hairpin turns. Had to slow way down for a tight turn which lowered my RPM's so much that the engine started to bog down. It almost stalled which would have put me in a difficult position given the steepness and my wife on the back. I just barely made it through the section.
 
#34 ·
What gear were you in?