How to replace your front sprocket

[iliveonnitro]

I just bought a '09 GS500F 7 weeks ago and I'm really enjoying it.  I've only put in 700mi, mostly due to not wanting to ride in the (huge amount of) rain as a beginner.  My commute to work is ~28mi round trip, ~10mi on the highway in each direction.  They tend to average 70-75mph on the highway, and I'd like a slightly taller gear, so I just put on a 17t front sprocket.  I had to sort through several posts to figure out how to do this, so I wanted to compile it into one thread.  Here are the steps:

Tools needed: 8mm, 10mm, 12mm, 22mm sockets, large adjustable crescent wrench, needle nose pliers, circlip/snap ring pliers, 55-60ftlb torque wrench, rag

1. Put the bike on the center stand
2. Remove the shift lever with a 10mm socket.  The bolt has to come all the way off because there's a safety retaining lock on it. Note the approximate angle of the lever.
3. Remove the cover bolts with a 8mm socket.  It's the one with the (clutch) cable running into it.
4. Using circlip pliers (try not to use ones with a 90 degree bent tip), spread the retaining ring open and use needle nose pliers to grab and pull it out.
5. Slide off the stock 16t sprocket.
6. Loosen the 22mm axle bolt (left side).  I held the other side in place with an adjustable wrench.
7. Loosen the chain adjustment screws the same number of turns on each side.  I did about 3.5 turns.
8. With a rubber mallet/something similar, smack the axle bolts so that the rear axle slides forward and the chain is slack.
9. Slide on the 17t sprocket.
10. Reattach the circlip -- it's much easier to get on.
11. Bolt the cover and shift lever back onto the bike, making sure the cover is properly seated.
12. Tighten the axle so that it is snug (but can still slide).
13. Tighten the two rear nuts to take the slack out of the chain.  0.8"-1.2" of slack upward, measured from just aft of hte centerstand foot.
14. When you hit the correct tension, tighten the rear axle nut to 55-60ft lbs. You should really use a torque wrench.
15. Roll the bike forward a few feet and check again to make sure it worked.

Done!  It took me 28min...it probably would have taken 20min or less if I had better circlip pliers.

James