Kawi2strokes.com Forum

Enthusiasts from around the world dedicated to the preservation and ritual flogging of the infamous Kawasaki 2-stroke Triples
It is currently Sat Apr 27, 2024 1:20 pm

Board index » Our legendary Kawasaki Triples » Troubleshooting, How-to, and General Wrenching

All times are UTC - 5 hours




Post new topic Reply to topic  Page 2 of 2
  [ 20 posts ]  Go to page Previous  1, 2
  Print view Previous topic | Next topic 
Author Message
concours
PostPosted: Sun Dec 04, 2022 9:08 am 
User avatar

Joined: Thu Sep 29, 2022 5:09 am
Posts: 31
Location: Kensington, NH USA
H2RTuner wrote:
Street pistons were cast, .001 clearance.

Original H2-R pistons were factory forged, and worn completely out in 3 laps.

Latest H2-R and all the KR series were pressure die cast, clearances .0015, NEVER HAD A PROBLEM WITH THEM, got 150 race miles from them and rings, didn't sound like they were completely worn out. They worked great up to rev limit of 10,300 RPMs.

After I pulled them out of the race engines, I'd run 'em in my street engines, not one problem. Yes, I also had a N
KR750 set up for the street, H2-R, too.


A thou & a half? That's TIGHT!

_________________
WFO for 51 years
1974 Norton Commando 850 Roadster
1974 H2B
1975 Yamaha DT400B
1984 RZ350
2007 Tiger 1050
2014 Rocket III Touring
Top
 Profile  
 
H2RTuner
PostPosted: Sun Dec 04, 2022 10:09 am 

Joined: Thu Jun 09, 2011 11:25 am
Posts: 3146
The whole idea is to keep the piston from excessive rock over at both TDC and BDC, so the rings would seal.

Too much clearance, extreme power loss.
Top
 Profile  
 
concours
PostPosted: Fri Jan 06, 2023 12:04 pm 
User avatar

Joined: Thu Sep 29, 2022 5:09 am
Posts: 31
Location: Kensington, NH USA
Retro 3 wrote:
https://www.ebay.com/itm/253553457365

These could be cast, not sure


Indeed, these are Japanese made, cast pistons, and Japanese rings as well. Thank you for the heads up. :thumbup:

_________________
WFO for 51 years
1974 Norton Commando 850 Roadster
1974 H2B
1975 Yamaha DT400B
1984 RZ350
2007 Tiger 1050
2014 Rocket III Touring
Top
 Profile  
 
Stev-o
PostPosted: Mon Jan 09, 2023 4:38 pm 

Joined: Sat Oct 04, 2014 3:45 am
Posts: 796
Location: Cen Tex
concours wrote:
....you are riding around with loose, rattly pistons.


Ah...no I'm not! I have Wiseco's in my H2 and my CB750 [punched out to 836] and neither has "rattly pistons".

I bought them at the suggestion of my machinist, he builds Kawasaki drag bikes, and no regrets here.

_________________
H2B..... H1E..... Z1B ..... RD350...... X6 Hustler..... TS250.... CB750 ..... CB550...... and a Bomber!!
Top
 Profile  
 
concours
PostPosted: Mon Jan 09, 2023 8:23 pm 
User avatar

Joined: Thu Sep 29, 2022 5:09 am
Posts: 31
Location: Kensington, NH USA
Stev-o wrote:
concours wrote:
....you are riding around with loose, rattly pistons.


Ah...no I'm not! I have Wiseco's in my H2 and my CB750 [punched out to 836] and neither has "rattly pistons".

I bought them at the suggestion of my machinist, he builds Kawasaki drag bikes, and no regrets here.

I'm the FNG here. I know the rules. Pretty sure you want to convince me you are right. No offense, I've seen the movie many times.

Here's more of my post: "Not wanting to perpetuate an "oil thread" of emotional responses here, nor calling anyone's baby ugly."

Peace.

_________________
WFO for 51 years
1974 Norton Commando 850 Roadster
1974 H2B
1975 Yamaha DT400B
1984 RZ350
2007 Tiger 1050
2014 Rocket III Touring
Top
 Profile  
 
COOPS
PostPosted: Sat Apr 08, 2023 12:08 am 

Joined: Sat Jun 11, 2011 11:11 pm
Posts: 464
Location: New Zealand
I’m all for cast pistons. That’s what I will use when I rebore my street H1
My race H1 I used Wossner. That was about six years ago. Six seasons at
Full throttle. Actual full throttle, not occasional full throttle.
Still going strong. No rattles.
Just an observation. Wossner have been good to me :thumbup:
Top
 Profile  
 
Hawaii-Mike
PostPosted: Sat Apr 08, 2023 2:24 am 

Joined: Tue Jul 24, 2012 6:06 pm
Posts: 1137
Location: Honolulu
Cast pistons $482 https://www.ebay.com/itm/253553457365

Wossners $136 x 3 = $408 https://www.fastfromthepast.com/98-h2060

Why not buy the Wossners? They are the best pistons. They will cost a little more with shipping cost added.
Top
 Profile  
 
H2RTuner
PostPosted: Sun Apr 09, 2023 10:26 am 

Joined: Thu Jun 09, 2011 11:25 am
Posts: 3146
Wossner are the best FORGED piston, tightest of the forgings, but too loose for street use.

Drag racing uses the loosest fit as those engines do not run long enough to equalize cylinder expansion.

As I said, I set cast pistons up at .001 to .00125, never have had a problem doing it that way.

Road race engines, Wossner, .0025, drag racing, Wossner, Wiseco, .0035+ (doesn't matter, they are two runs maximum units). I do not run the road race & drag race engines on the street.
Top
 Profile  
 
rotortiller
PostPosted: Sat Apr 15, 2023 6:38 am 
User avatar

Joined: Thu Jul 26, 2012 3:05 pm
Posts: 41
I run Wossner H2s at just over .002", got over 5000k on them with no audible slap. I think .0025" is what the manufacturer specs out and what I followed. Good quality pistonians and I would certainly recommend them. It's on a street bike and compression value is the same as new. The only thing I do not like is that the ring pins are lined up, however that does not seem an issue and is more of a tech perfection azzwipe opinion thing.
Top
 Profile  
 
Hawaii-Mike
PostPosted: Sat Apr 15, 2023 7:32 pm 

Joined: Tue Jul 24, 2012 6:06 pm
Posts: 1137
Location: Honolulu
I have a set of Wossners on an H2 motor, several thousand street miles and rattle free.
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  Page 2 of 2
  [ 20 posts ]  Go to page Previous  1, 2

Board index » Our legendary Kawasaki Triples » Troubleshooting, How-to, and General Wrenching

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group