Piston rings set

  • Tjpgi
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Piston rings set

24 Sep 2025 14:00 - 24 Sep 2025 14:01
#917593
1976 KZ 900. Previous owner bored out to 70mm ART pistons. I tore done the engine because of poor performance and low compression. Valves were the source of low compression. I want to replace the rings after cylinder hone. I can't seem to find ART manufactured rings for a 70mm piston. CanI use an alternate manufacturer for the rings? Would like to avoid replacing the pistons. Any suggestions?
Last edit: 24 Sep 2025 14:01 by Tjpgi.

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  • zed1015
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Re: Piston rings set

24 Sep 2025 15:08 - 24 Sep 2025 15:25
#917596
ART pistons are OEM equipment so the 70mm ones are almost certainly Z1000 so genuine Z1000 rings are very likely what you need.
However ! a popular high comp over bore back in the day was to use Honda CB450 or 500 twin pistons ( Also ART )  which have higher domes so it's possible you may have these.
If you post a pic of your pistons i can confirm what you have.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
www.kzrider.com/23-for-sale/611992-air-c...lide-mikunis?start=0





Last edit: 24 Sep 2025 15:25 by zed1015.
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Re: Piston rings set

25 Sep 2025 00:38
#917606
Or another proven option, NPR rings. I've been using them for years when reusing the stock cast ART pistons. If you Truly have a proper fitting ART 70mm KZ1000 supplied set of pistons rings would be Kawasaki Part # 13008-5012. NPR part number is 008-5012 or supplier K&L 11-2982. There are several vendors on Ebay that furnish 4-complete sets for around 100USD.  
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  • Wookie58
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Re: Piston rings set

25 Sep 2025 00:48
#917607
Depending where in the world you are (US would be pricey these days) IMD in the UK can also supply these

1982 KZ1000 Ltd
www.kzrider.com/forum/11-projects/617631...-82-begins?start=192
kzrider.com/filebase-alias?view=download...d-fault-diagnosis&ca
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  • sf4t7
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Re: Piston rings set

25 Sep 2025 05:43
#917616
IMD has a wide selection of pistons and/or rings.  They had rings to fit my Yoshimura 987cc pistons (from back in the day when race motors had to be under 1000cc). Even better, they came gapped correctly for my bore size. (Still a good idea to check them anyway). Glad I bought them last winter, though!
Scotty

1974 Z1A
Yoshimura 987
welded Z1 crank
Andrews 1X Cams
Delkevic 4 into 1
Superbike bars
530 conversion
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Re: Piston rings set

25 Sep 2025 08:02
#917621
Have someone any experiences with this piston rings, ore the supplier?


Greetings, Joe

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  • Bloobaba
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Re: Piston rings set

25 Sep 2025 08:33
#917624
A friend installed Cruzynimage segments on a GPZ1100B2 a few years ago, and they haven't had any problems since. I'll let you calculate the customs fees 🤣

www.cruzinimage.net/2017/09/07/77-79-kaw...0mm-4rings-included/

 
Z400F 84 (ZR400B1)
Gpz900R 84
500 H1 73
Gpz550H1

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  • Tjpgi
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Re: Piston rings set

25 Sep 2025 18:04 - 25 Sep 2025 19:11
#917638
Thanks to everyone for the input. Here's some pictures of the project bike and a piston.
Do you guys think this piston/ring kit for a 77 KZ1000 (standard bore) work?
ebay.com/itm/304952801100
Last edit: 25 Sep 2025 19:11 by Tjpgi. Reason: Information

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  • zed1015
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Re: Piston rings set

25 Sep 2025 23:40 - 25 Sep 2025 23:41
#917641
Tjpgi wrote:
Thanks to everyone for the input. Here's some pictures of the project bike and a piston.
Do you guys think this piston/ring kit for a 77 KZ1000 (standard bore) work?
ebay.com/itm/304952801100
Your pistons appear to be Honda CB450/500 twin so you will need two sets of std rings for those.
I've had a few 900's with the Honda pistons fitted as shown in the attached pic.

AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
www.kzrider.com/23-for-sale/611992-air-c...lide-mikunis?start=0





Last edit: 25 Sep 2025 23:41 by zed1015.

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  • Wookie58
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Re: Piston rings set

26 Sep 2025 03:07
#917643
Tjpgi wrote:
Thanks to everyone for the input. Here's some pictures of the project bike and a piston.
Do you guys think this piston/ring kit for a 77 KZ1000 (standard bore) work?
ebay.com/itm/304952801100
piston to bore clearance is critical and since your cylinder was bored to the pistons you have the clearance may not be correct with the kit you have posted. I would suggest you take Zed’s advice ref rings or go to the first oversize with IMD kit and bore accordingly (IMHO)
1982 KZ1000 Ltd
www.kzrider.com/forum/11-projects/617631...-82-begins?start=192
kzrider.com/filebase-alias?view=download...d-fault-diagnosis&ca
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  • TexasKZ
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Re: Piston rings set

26 Sep 2025 07:00 - 26 Sep 2025 07:01
#917655
Seems like a good idea to have a machinist check the piston to bore clearance, since you do not know how the bike was treated in its former life, nor how many miles are on those pistons.
If the clearance is good, then new rings is an option. If the clearance is not good, then boring is the only option.
1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough

www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24
Last edit: 26 Sep 2025 07:01 by TexasKZ.
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Re: Piston rings set

26 Sep 2025 12:31
#917668
Thanks for the info. I'm going to decarbon the top of the piston to give you a better picture. The top of the is raised in the center with an identation on top in the front and back.

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