Install a 16 Tooth Front Sprocket
 

This is fairly simple process. It actually took more time to reinstall the friggin' cotter pin than anything else.

Things you'll need:

17mm wrench
3/4" wrench
12mm socket
7mm socket
30mm socket (torque wrench)
alligator pliers
flat head screw driver
new sprocket


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PUT YOUR BIKE ON SOME STANDS

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The first thing that I did was remove the sprocket cover. There are three 7mm bolts that hold the cover on. They don't need to be torqued or anything.

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If your sprocket cover is dirty, this is probably a good time to clean the inside and remove all of the extra gunk from the chain goo.

Next, you'll want to remove the cotter pin and loosen the rear axle nuts. This is the easy part of the rear axle work.

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Work the chain tension bolts and loosen the chain to get some slack. YOU"LL NEED IT.

Now go back to the sprocket and bend the lock washer FLAT. This is important or you will never get the bolt off.

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Now, you'll need the 30mm torque wrench to get this bolt off. You'll also need to put the bike in gear and have someone press the rear brake pedal. I didn't have anyone to help. So, I sat on the bike and one handed the torque wrench.

Getting the old sprocket off is quite easy. Getting the new sprocket on isn't too hard, you just need to relax and make sure you push it on the little gear teeth with care.


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Slide the new sprocket on, reinstall the lock washer and bolt and tighten. You will need to make sure to REFLATTEN the lock washer once it's all good and tight.

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Once this is all done, retighten the chain per the manual's instruction and you're pretty much set.

You just need to reinstall the sprocket cover and YOU"RE DONE. GO FOR A RIDE!!!!

Here is a final shot of the difference between the 16 T sprocket and the original 15T sprocket

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First Impressions
 

After the first ride, all I can say is "WOW".

For those of you who think that first gear is useless, you need this new front sprocket.

I wasn't able to reach a higher top speed, but it wasn't because of the lack of engine. The extra mass of the sprocket must be holding back some of the GZ's punch, because there are plenty of revs left at 70mph. There just isn't enough grunt to carry it over the 70-75 mark quickly. I reached 75-78, but it took a while. This was on a slight incline of rolling road. IF I had a downhill, I have no dobut that I would have reached 90.

OK, the good stuff.

The gears are much more useable and cruising speed is increased without the vibration or buzziness.

1st gear is now capable of reaching 25+MPH without redlining
2nd gear will carry you to 30-35+. Again, without redlinig.
3rd gear is good for 40-46
4th gear can easily reach 60mph
5th gear will go on forever

It's important to note that these numbers come without having to goose the motor at all. These are all cruising speeds.

These numbers are'nt fantastic. However, anyone who spends a lot of time on the bike knows that the stock gearing isn't capable of reaching these speeds without frying the motor. I don't even think the stock gearing can do it while frying.

The most important part of the mod comes from the fact that riding on the highway(4 land roads) around 55-65 mph is no longer buzzy or nerveous.
The engine seems very smooth with this gearing in all gears and, again, I must stress that the increased speed comes with the engine doing less work.

I think this is a must do for anyone who spends a lot of time on the time or rides on speedier highways.

TOTAL COST= $18.95

Nice job on the How To guide!

I'm not sure if it's too coherent. I get busy watching the Braves and that kept most of my attention.
:2tup:

Well done job on the "How To". Both the text and phots were very professionally done.

Cheers!

Jonathan, excellant "how to" on the sprocket change. I have wondered about an extra tooth up front. Sounds like it might be the way to go. How many miles have you ridden before the change ?? And what condition were the chain and front sprocket in ??

Good job. :tup:

I've been considering doing this myself but decided to wait until I replace the chain. You have convinced me to its a good thing to do. Thanks.

Did you wash the bike before you started? Seems awfully clean.

Nice job. I think even I can do this. By the way, where did you buy the 16T sprocket?

BadBob,
were you making fun of my pollen covered rain-spot mobile? I sure hope not. The pollen count was really high for a while and I haven't really given the bike a good washing in a while.

David C83:
I bought the sprocket from www.bikebandit.com It's a JT front sprocket. Do a search by DRIVE components and then select JT - Suzuki and you'll see the GZ250. All of the years are the same. So, if you have to choose a 2004 or something, it will work on the newer models.

Water Warrior:
I had about 1500-1600 miles on the bike before the change. It's really worth it.

I didn't have to change the chain or anything and the original sprocket wasn't worn at all. It was alittle gunky from chain goo, but it's all good now. This whole process also allowed me to readjust the cahin tension. That's always nice.

Cheers,
Jonathan

Nah! Not making fun. Mine is greasy under that sprocket cover. I did notice rusty spots on the chain but not pollen.