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Old 04-18-2007, 08:50 PM   #1
jonathan180iq
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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




PUT YOUR BIKE ON SOME STANDS




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.



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.



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.



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.




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.



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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Old 07-24-2014, 12:42 PM   #2
golem
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Ok, so I installed a new front sprocket on my geezee and I simply don't recognize it anymore ! I was supposed to lose some speed ? Well , not in my case. It use to plateau at 60 mph and now I can easily reach 70mph !! I don't know why but I sure am happy about it. I also like the way the gears goes waaay better !
All in all, I recommend this mod to any owner of a gz even though YMMV. Thanks jonathan !

On a side note, would the bike benefit from a smaller back sprocket?

Last edited by golem; 07-27-2014 at 06:39 PM.
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Old 09-18-2014, 06:32 AM   #3
beefjerky
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This looks great and I want to do this mod to my 2000 GZ

Which sprocket should I pick from these?

Apologies if this is covered in the thread already.



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Last edited by beefjerky; 09-22-2014 at 04:46 AM.
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Old 09-22-2014, 03:19 PM   #4
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I don't know if this is going to help you but this is the one I got :
http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1
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Old 09-23-2014, 04:20 AM   #5
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You will know soon enough. Install the sprocket.



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Old 04-05-2015, 08:39 PM   #6
Suzuki-san
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got er dun - 16T

I bought the 16T JT Sprocket a while back, but finally got the nerve to do the swap. I'm glad I did, because the 30mm nut holding the 15T on was LOOSE! Thank goodness the bent washer was in place to keep it from unraveling!

Anyhoo, after studying the videos and reading this thread, and going over in my mind what I had to do, it was actually a pretty simple mod to do!

My experiences after the sprocket change to 16T is similar to other posters in this thread. I like that 1st gear is usable. The gears are spread out more, and it seems to run smoother. To me, the acceleration is as good if not better than before from start to 50+mph. I saw little or no loss in torque, esp. considering I am overweight by 100lbs or so. (curse you Krispy Kreme bacon donut dog... CURSE YOU!)

And as some of you have mentioned, and I am experiencing it as well, 5th gear is almost useless. At best it can hold a speed like 60mph. Try to accelerate, and it bogs down and goes slower. I guess it is too much for that engine to take the bike, my heavy self, a headwind plus doing 60mph, to do much more. The rest of the bike is stock. May consider rejetting the carb at a later date to compensate.

OVERALL I still like the mod. It is cheap to do and easily reversed if not satisfied.
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Old 04-16-2015, 12:20 PM   #7
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Quote:
Originally Posted by Suzuki-san View Post
I bought the 16T JT Sprocket a while back, but finally got the nerve to do the swap. I'm glad I did, because the 30mm nut holding the 15T on was LOOSE! Thank goodness the bent washer was in place to keep it from unraveling!

Anyhoo, after studying the videos and reading this thread, and going over in my mind what I had to do, it was actually a pretty simple mod to do!

My experiences after the sprocket change to 16T is similar to other posters in this thread. I like that 1st gear is usable. The gears are spread out more, and it seems to run smoother. To me, the acceleration is as good if not better than before from start to 50+mph. I saw little or no loss in torque, esp. considering I am overweight by 100lbs or so. (curse you Krispy Kreme bacon donut dog... CURSE YOU!)

And as some of you have mentioned, and I am experiencing it as well, 5th gear is almost useless. At best it can hold a speed like 60mph. Try to accelerate, and it bogs down and goes slower. I guess it is too much for that engine to take the bike, my heavy self, a headwind plus doing 60mph, to do much more. The rest of the bike is stock. May consider rejetting the carb at a later date to compensate.

OVERALL I still like the mod. It is cheap to do and easily reversed if not satisfied.
I went looking for a JT 16T replacement sprocket online, I found different thickness 16T sprockets available, what thickness suits the GZ with stock chain? or does anyone have a part number?

Id toyed with the idea of getting a larger engined replacement bike, but for a few reasons that idea has fizzled out. Really the most cost effective thing for me to is just to try some of the simple mods on the GZ to try improve its characteristics which suit me well enough for what and how I use it already.
It'd be a shame not to try it really, and the idea of not having to change up a gear almost immediately sounds good. Dont know if a carb mod is needed or is better to do if changing the sprocket, which Ive read is recommended on another older thread

Last edited by jonathan180iq; 04-16-2015 at 04:00 PM.
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Old 04-05-2015, 08:59 PM   #8
raul10141964
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I recommend to mode the carburetor and air cleaner.
I wait 230 lb and hold 70 mi or more with no problems
I running a 140 main jet and mod factory air cleaner see the pic
The mode filter do not work with factory main jet
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Old 04-16-2015, 01:01 PM   #9
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mod the carb and filter gibe you 1 to 2 HP more and make the engine rune colder
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Old 04-16-2015, 03:05 PM   #10
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I might try that too, but its not extra HP Im after in particular (is it a noticeable difference though?)
Making first useful and the prospect of the engine not reving as high as it seems to, is more what Im after, this seems to be described as the effect of changing the sprocket from a 15t to a 16t.
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