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Does anybody know if the racing valve springs are stiffer than the stock ones?
http://www.kawasaki.com/KawasakiNew/Accessories2/PCItemDetail.aspx?ItemNumber=490780049&Reason=6&intCatalogID=1&intCatalogType=26&ProductTypeID=14&ModelMarketingId=565&ModelYear=2008&CategoryID=132


As some may remember, I get three lobes of my race intake cam rounded (http://www.zx-10r.net/forum/showthread.php?t=54998&highlight=catastrophic), and now going into a custom cam (intake and exhaust). I may be in the need of stiffer springs.

Would appreciate any info you can give me:thumbsup:
 

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Does anybody know if the racing valve springs are stiffer than the stock ones?
http://www.kawasaki.com/KawasakiNew/Accessories2/PCItemDetail.aspx?ItemNumber=490780049&Reason=6&intCatalogID=1&intCatalogType=26&ProductTypeID=14&ModelMarketingId=565&ModelYear=2008&CategoryID=132


As some may remember, I get three lobes of my race intake cam rounded (http://www.zx-10r.net/forum/showthread.php?t=54998&highlight=catastrophic), and now going into a custom cam (intake and exhaust). I may be in the need of stiffer springs.

Would appreciate any info you can give me:thumbsup:
I have a RIMAC spring tester, like all the NASCAR and NHRA teams use and tested some of the race / stock springs a while back.

The Kawi race springs are significantly stronger on the Exhaust side and about the same on the intake side to max stock lift, then slightly stronger the next .5MM of lift.

So Yes, slightly stronger on intake versus stock, and considerably stronger on the exhaust side.

If you do a search you might find the thread I did with pix of the springs being measured on the tester.

JJ
 

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The Orient Express springs are made by APE, and are no longer produced. If you can find a set, buy them, the only other option is Carpenter, and they are very stiff and more expensive.
 

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Yea, we were looking at the differences from the 11 14 and 10 and the damn things are pretty similar just bigger or smaller depending on displacement:lol:
 

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The kit springs for the '08 are designed to work with the kit cams, which are significantly lighter. Haven't checked into it with any depth (we run different springs), but I wanna say based on this they'd have less tension. The kit cams being sbk legal, wouldn't have any more lift, and just slightly more duration, but as I wrote, are significantly lighter.
 

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hey advanced kawi, are they going to be running the same duration as the 04-07 kit cam..... from what i have read the lift on the 08's is the same as the 04-07 kit cams but have a lil less duration..... what kinda numbers are we gunna see do u know?

have a part number at all by any chance???
 

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Does anybody know if the racing valve springs are stiffer than the stock ones?
http://www.kawasaki.com/KawasakiNew/Accessories2/PCItemDetail.aspx?ItemNumber=490780049&Reason=6&intCatalogID=1&intCatalogType=26&ProductTypeID=14&ModelMarketingId=565&ModelYear=2008&CategoryID=132


As some may remember, I get three lobes of my race intake cam rounded (http://www.zx-10r.net/forum/showthread.php?t=54998&highlight=catastrophic), and now going into a custom cam (intake and exhaust). I may be in the need of stiffer springs.

Would appreciate any info you can give me:thumbsup:


Here is the link to the thread I did on these a while back. Testing 06-07 stock intake / stock exhaust and Race springs on my Rimac spring tester. I have not tested the stock springs on the 08. I may buy one of each and give it a try.

http://zx-10r.net/forum/showthread.php?t=39380&highlight=Rimac

JJ
 

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I have never measured APE's srpings. Unlike Kawi they wont just sell me one to test. But keep in mind the stronger the spring the more effort it takes from the crank to compress it. So we wouldnt want to throw super strongs springs in there that are far more than needed.

The Kawi race springs look good to me. I have used them in the past from the ZX7 Race kit parts as well.

Now Titanium Retainers would be a nice touch. Alas I have not been able to find any.

JJ
 
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