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Author [ES] [MY] [PL] [PT] [IT] [DE] [FR] [NL] [DK] [NO] [GR] [TR] Topic: Changing sprockets  (Read 12989 times)

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Offline Rolltide97

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Re: Changing sprockets
« Reply #80 on: May 15, 2019, 12:48:08 PM »
I put a 16t on the front and went down to 41t on the rear.  I ride rather conservatively and do a lot of interstate miles, so I wanted to lower my RPMs.  This setup did just that.  I feel like I actually have 6 gears now.  My mechanic tried to put a 17t on the front, but you have to remove a chain guard piece to make it fit.  I didn't want to do that.  My speedometer is a little off now.  My bike says I'm going 75, but my GPS says 71.  Anybody know that best way to resolve this?  Speedohealer or SpeedoDRD or something else?

Offline Scim77

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Re: Changing sprockets
« Reply #81 on: May 23, 2019, 10:32:12 AM »
Refer to a recent post by Matt Hudson. Your speedo signal is taken from the rear wheel, so it will not be affected by different sprocket sizes. Any discrepancy that you have observed between speedo and sat nav would have been there even before you changed the sprockets. There is nothing to 'heal'.   5% to 10% fast is about the norm these days.

HOWEVER !!!   Grrr !!   I was riding last night and my engine management light came on. It was code 25, gear position indicator. I had read in other posts on this forum that this issue had arisen some time after changing the sprockets. I very much doubt that there is anything wrong with my sensor/ECU or wiring. But I think that the factory mapping is noticing conflicting information from its various speed sensors, i.e. The rear wheel speed sensor is not tallying with the engine speed sensor, for the gear as indicated by the position sensor.  DRAT!  I very much doubt that there is anything we can do to swerve this problem. By changing the sprockets, we have deviated too far beyond the calculated parameters mapped into the ECU.

So, very reluctantly, I might have to change back to standard 15/44 sprockets, even though I much preferred the longer gearing of my 16/41. I will probably do it in stages, 16/44 initially, then if that fails I will revert to standard 15/44. Disappointing.

Who in their right mind would design a vehicle that falls over when it stops?

Offline Rolltide97

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Re: Changing sprockets
« Reply #82 on: May 23, 2019, 11:43:34 AM »
Oh no, that stinks.  I hope mine doesn't give me that error and force me to revert back to 15/44.  I'm loving 16/41.

Offline MZ900

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Re: Changing sprockets
« Reply #83 on: May 23, 2019, 11:45:18 AM »
Have you tried with this set up your max spees on the 1st gear?

Offline Rolltide97

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Re: Changing sprockets
« Reply #84 on: May 23, 2019, 11:53:32 AM »
Not max speed in first, but I did get almost to 50mph and didn't hit the redline.  I didn't push it, but I bet you could get close to 60 without shifting into second gear.  I don't even get into sixth gear unless I'm on the interstate now.

Offline Scim77

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Re: Changing sprockets
« Reply #85 on: May 23, 2019, 12:02:14 PM »
*Originally Posted by MZ900 [+]
Have you tried with this set up your max spees on the 1st gear?

I get around 65mph in 1st at 9500rpm (speedo reading). So it is probably just over 60. Every gear feels wonderful and hurls the bike down the road seamlessly, like a long-legged missile.

Cruising at UK motorway speeds of 70mph in 6th pulls around 4200rpm and uses less fuel than stock. I tread down a couple of gears if I want the thing to accelerate rapidly.
I guess an experienced tuner who knows how to tweak a re-map would be able to overcome all this sensor confusion. Now that might be a good route, once I am out of warranty.
Who in their right mind would design a vehicle that falls over when it stops?

Offline MZ900

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Re: Changing sprockets
« Reply #86 on: May 23, 2019, 02:24:05 PM »
Noice !

I have only 16th on the front, but didnt tried bike yet.

Offline porkchop

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Re: Changing sprockets
« Reply #87 on: May 23, 2019, 02:24:35 PM »
*Originally Posted by zed9 [+]
I also have a ZRX1200 which is a torque monster. I expected the z900 to feel gutless next to it but that is not the case. The ZRX has torque everywhere, the z900 has torque almost everywhere by comparison. When the testers consider the z900 a torquey bike you can believe them.

So do the front first, if you need more then do the rear but I don't think you'll need to. And don't worry about the power, she's got it.


Zed 9,
I went to 16/44 on my 1200, huge change as it pulls much better (full exhaust / jetted / pods also), raised RPM about 5-600 but still good at highway speeds- only kills my fuel MPG when I'm on it often.
Have to agree about the 900, it's light, nimble + so smooth compared to the REX.
Haven't had the front wheel up yet but I made a good choice, definitely gear this one too  :001:
"The ride is the reason"

Online zed9

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Re: Changing sprockets
« Reply #88 on: May 23, 2019, 04:15:40 PM »
*Originally Posted by porkchop [+]

Zed 9,
I went to 16/44 on my 1200, huge change as it pulls much better (full exhaust / jetted / pods also), raised RPM about 5-600 but still good at highway speeds- only kills my fuel MPG when I'm on it often.
Have to agree about the 900, it's light, nimble + so smooth compared to the REX.
Haven't had the front wheel up yet but I made a good choice, definitely gear this one too  :001:
The lightweight z900 has spoiled me, I now pretty much just use the Rex for long distance touring most of the time anyways. I love them both.

Offline Scim77

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Re: Changing sprockets
« Reply #89 on: June 04, 2019, 12:47:01 PM »
Has anyone else experienced the EML light (code 25) coming on, when running either 16/44 or 16/41?

I spoke with Kawasaki technical, who confirmed that the factory mapping would notice the deviation from factory 15/44 and throw up a warning light, as I suspected.  I also asked them what the tolerance was, in case 16T alone might be tolerated but they did not know. For example, if we had a 7% tolerance, then either a 16T front OR a 41T rear might go unnoticed by the mapping.

How many miles have you 16T guys done and has the EML had come on yet?
Who in their right mind would design a vehicle that falls over when it stops?