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Offline Frontline

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #10 on: April 20, 2021, 12:03:46 PM
*Originally Posted by jward21391 [+]
It’s happened just a few times. Never been any sort of noise, grind or hard shift. Think there could be a deeper issue outside of just loosening the clutch cable a little?
Ehhh, maybe its fine as long as you didn't remain on the gas when it was slipping. A very short slip here or there isn't going to hurt long term.

When a clutch slips, you don't get grinding, noise or hard shifting (unless extreme). What happens is the clutch metals get super hot, warp and can then cause the clutch friction plates to rapidly wear and can even smear from the intense heat. The metals once turn dark (bluing), they are finished and will never be the same. The engine oil gets burnt...ect...

At the very least, if you find the clutch is not adjusted correctly (from factory, mind you), the dealer needs to see this or notified. If documented, you are (hopefully) covered if you get per-mature clutch wear in the future. Sometimes early on clutch issues don't show themselves till many miles later as normal wear happens.

Really sucks you must go through this on a brand new machine.
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Offline zed9

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #11 on: April 20, 2021, 02:37:37 PM
If you've burned your clutch already, good luck getting the dealer to admit their fault for letting you ride off with an improperly adjusted clutch. They'll either tell you there's no warranty on consumable parts or they'll blame you for it. True story. Probably blame you since there's only 200 miles on it.

You should consider adding Brock's springs the minute your bike is out of warranty. Or now.

Online 3alfa3

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #12 on: April 20, 2021, 03:45:31 PM
*Originally Posted by zed9 [+]
You should consider adding Brock's springs the minute your bike is out of warranty. Or now.

had no problem with stock springs in 17000+ km (2020 model), but, my clutch cable slack is 3mm
Last Edit: April 20, 2021, 03:47:09 PM by 3alfa3

Offline zed9

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #13 on: April 20, 2021, 06:21:44 PM
*Originally Posted by 3alfa3 [+]
had no problem with stock springs in 17000+ km (2020 model), but, my clutch cable slack is 3mm
I'm anal about maintenance and adjustments yet I had my '17 clutch slip once. Knowing about other owners slippage problems I ordered the Brock's springs and it hasn't slipped once since I installed them.
Kawi changed something in the clutch in 2018 I think. A different friction plate maybe, I can't remember.

Online 3alfa3

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #14 on: April 20, 2021, 07:03:58 PM
*Originally Posted by zed9 [+]
I'm anal about maintenance and adjustments yet I had my '17 clutch slip once. Knowing about other owners slippage problems I ordered the Brock's springs and it hasn't slipped once since I installed them.
Kawi changed something in the clutch in 2018 I think. A different friction plate maybe, I can't remember.

This (2020) is my first z900, so can't compare, but, i still dont know why would clutch slip given angles on clutch basket (assist clutch) that make more pressure as torque rise. Am i missing something?

Offline zed9

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #15 on: April 20, 2021, 08:01:13 PM
*Originally Posted by 3alfa3 [+]
This (2020) is my first z900, so can't compare, but, i still dont know why would clutch slip given angles on clutch basket (assist clutch) that make more pressure as torque rise. Am i missing something?
In my un-expert opinion, the "assist" function combined with the race to see what manufacturer has the lightest clutch IS the problem!

Because the "assist" ramps are there, they (think they) can get away with lighter springs to make a clutch pull so easy that five year olds could use. Personally, I enjoyed the light clutch... right up to the time it slipped.
The Brock's springs seemed to have solved the problem and the extra pull needed to work the lever is barely noticeable. It is still a light clutch which makes my other two bikes seem cave-man by comparison. And I used to think of those as light beforehand.

Plus with the Brock springs, at least I can feel the lever in my gloved hand. Highly recommended.

Offline Z900-WA

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #16 on: April 20, 2021, 11:39:39 PM
Do u remember about how much the new clutch plates were?

Saw Brocks super in depth Z900 Dyno Tuning Vid recently. He specifically says he thot the clutch  mighta slipped due to extra hp from swapping to the Brocks Exhaust. Sounded a bit far fetched, but still piqued my interest.

Haven't had a chance to look it up myself yet, so if u remember I'd be interested to learn. Thanks

&re 2020 Z-Slipping. Def Return to dealer for inspection / Documenting of issue asap. Regardless of the root cause, most dealers charge $500+ Extra for the Dealer prep / delivery fee, which consists almost entirely of attaching the mirrors & maybe a license plate, plus a filling out a certificate of inspection, attesting to the completion of thorough pre-sale safety and vehicle operating condition checklist.

Which means its the dealers responsibility to make sure that everything adheres to the manufacturers specs before delivering to the customer.

Verifying the clutch is properly adjusted is def part of that checklist & worst case is there's a deeper issue causing the problem, u Def want to get it inspected & documented asap

Offline Cazzy_R

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #17 on: April 20, 2021, 11:55:28 PM
*Originally Posted by Z900-WA [+]
Do u remember about how much the new clutch plates were?

Saw Brocks super in depth Z900 Dyno Tuning Vid recently. He specifically says he thot the clutch  mighta slipped due to extra hp from swapping to the Brocks Exhaust. Sounded a bit far fetched.......

 Brock may be a great tuner but he's an even better salesman.  :008:

 I had never noticed clutch slip per se on my 2017 but since fitting heavier Barnett springs (shipping costs for Brock's too high for my wallet) it's apparent that the the originals were causing a rubber banding effect under load at high revs. The bike definitely drives much harder than before.
Tighten it 'til it strips then back it off half a turn.

Offline KawaJagz

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #18 on: April 21, 2021, 01:18:46 PM
I have also noticed a small amount of slipping if really gunning it and have thought about getting some stronger springs, but haven't got around to it yet.
I used to be indecisive, but now I'm not so sure!

Offline Cazzy_R

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Re: ‘21 Z900 Revving out on quick acceleration
Reply #19 on: April 21, 2021, 02:06:46 PM
*Originally Posted by 3alfa3 [+]
.........i still dont know why would clutch slip given angles on clutch basket (assist clutch) that make more pressure as torque rise. Am i missing something?

 I can't argue with your logic.
 However what I can tell you is that the slipper clutch in a Z1000SX or Versys 1000 is identical to the Z900 (2018 on) except for longer (more preloaded) springs.
 Why would they do that and sacrifice the lightest possible clutch lever?
 Perhaps because of the 1000's extra weight and torque the clutch ramps need a little extra help from the additional spring force to fully engage under load?
 So if you weigh more, carry more or have increased power and torque the Z900 springs MAY be slightly under clubbed?

 All this in conjecture on my part but uprating the springs has no downsides in my experience.
Tighten it 'til it strips then back it off half a turn.