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Old 04-05-2015, 09:39 PM   #281
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 04-05-2015, 09:59 PM   #282
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, 01:20 PM   #283
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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



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Old 04-16-2015, 02:01 PM   #284
raul10141964
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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, 04:05 PM   #285
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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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Old 04-16-2015, 04:19 PM   #286
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The extra hp Wil be noticeable on fifth giar
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Old 04-16-2015, 05:02 PM   #287
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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.
Definitely. Lowering engine cruising speeds was my original intent and for that there is not an easier mod.

Also, as Raul said, up-jetting to a richer fuel mixture will help keep exhaust gasses a bit cooler and possibly help in engine longevity.
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Old 04-16-2015, 06:46 PM   #288
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Do either of these mods affect fuel economy? for good or bad
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Old 04-16-2015, 06:48 PM   #289
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60 mph
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Old 04-16-2015, 08:31 PM   #290
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Do either of these mods affect fuel economy? for good or bad
Shouldn't be enough difference to sweat over at the pumps. A rider's right hand has a lot to do with economy.
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