Front sprocket 15T vs 16T

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Re: Front sprocket 15T vs 16T

Postby David Richard » 12 Jan 2018, 20:25

hi on my d2 at 6 k its doing 80 mph ,that's with a 17 front and a 39 rear I'm sure you will notice a change with a 16 tooth ,david
David Richard
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Re: Front sprocket 15T vs 16T

Postby hugojose » 13 Jan 2018, 00:25

ZR468 wrote:
hugojose wrote:No, unless you are racing (...and you shouldn't be on these old ladies), the slightly slower acceleration will not be noticed. This is a trade off; less revs = Lower acceleration, higher top speed..... Higher reves = Higher acceleration, less top speed.

The RPM will drop about 300. The chain will appreciate the bigger sprocket. I run a 17T. The successor to the Zephyr, and last KZ750 in North America, the ZR-7 came with 16/39 combination, vs the 15/38 of the Zeph, which would drop the revs about 400

Just figured the math of the gear ratios of the front and rear sprockets. It gave me a point of reference to the different RPM drops. From the parts catalog, I see the ZR750 - C2 comes with 15/39 combination and the ZR-7S (2002) comes with 16/38 combo.
Hogojose, do you want to double check your combinations?

I did and you right. I simply had the rears mixed on print, and do have the factory manuals for both bikes. But the facts remains, the newer ZR-7 with same engine had more moderate gearing than the original Zephyr 750. Keeping the 39T at the rear, even the 16T will not drop the revs as much as the ZR-7's, only the 17T will drop the revs below the ZR-7's with 16/38 combo.
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Re: Front sprocket 15T vs 16T

Postby ZR468 » 15 Jan 2018, 17:05

Just placed an order for the 16T front sprocket on Ebay. It is coming from UK. The next step is installing it. My calculation is showing a 6.15% drop in RPM at the same speed compared with the OEM 15T. I am looking forward to it.
Btw, was out for a cold ride yesterday, 9C and foggy, but still nice break from the daily routine of driving a car.
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Re: Front sprocket 15T vs 16T

Postby hugojose » Today, 12:49

....and impact gun makes it a lot, a lot, a lot easier.
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Re: Front sprocket 15T vs 16T

Postby Richard » Today, 15:55

and a large enough compressor as I found out the hard way...
A regular hobby kind of type will not do :roll:
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