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Main Area => General GS500 Discussion => Topic started by: Chuck on November 28, 2006, 08:30:01 AM

Title: Newer kat shocks?
Post by: Chuck on November 28, 2006, 08:30:01 AM
Would this or this be cool?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=260058010466
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=110060257506

The newer kat shocks have the remote reservoir, but I figure with no airbox there should be ample room to mount it.  Has anyone tried shocks from this family, or know if they fit or behave well in the GS?
Title: Re: Newer kat shocks?
Post by: Jarrett on November 28, 2006, 11:05:39 AM
The first one you have listed is not a direct fit.  The base of the coil makes contact with the swing arm.  It wont bolt in unless you do some serious grinding.  No experience with the second listing. 
Title: Re: Newer kat shocks?
Post by: The Buddha on November 28, 2006, 12:04:55 PM
That first one like he said does hit the swingarm, but you have different linkages on different GS'es, one with the aluminum linkage is just a shade longer and will let it fit. In some cases you can rotate the shock or spring out to where it will fit. I also have heard of people grinding the swingarm.
Whatever you do ... do not grind the shock. Its spring is brittle ... grind it and it will snap ...
Cool.
Srinath.
Title: Re: Newer kat shocks?
Post by: Chuck on November 28, 2006, 12:24:31 PM
Okay, but how do I know if a particular shock, even if it fits, will work well?  There's some geometry in the linkages and swingarm which means the amount of deflection the shock receives is not easily matched (by me) to how the rear wheel deflects.  So I could take a shock from a bike that performs well with the same weight of a GS, but because of the geometric differences between the two bikes, it might be twice as stiff as it should be.  Or something like that.

My question is basically how do I go beyond just doing what other people have already done?  Is there any place where I can look up the physical properties of parts (length, spring constant, damping, etc...)?  If I could do that, I could say "well those numbers look close to what I want" and the only problem would be if it fits.

Does that make sense?
Title: Re: Newer kat shocks?
Post by: TragicImage on November 28, 2006, 12:26:43 PM
Quote from: Chuck on November 28, 2006, 12:24:31 PM
Okay, but how do I know if a particular shock, even if it fits, will work well?  There's some geometry in the linkages and swingarm which means the amount of deflection the shock receives is not easily matched (by me) to how the rear wheel deflects.  So I could take a shock from a bike that performs well with the same weight of a GS, but because of the geometric differences between the two bikes, it might be twice as stiff as it should be.  Or something like that.

My question is basically how do I go beyond just doing what other people have already done?  Is there any place where I can look up the physical properties of parts (length, spring constant, damping, etc...)?  If I could do that, I could say "well those numbers look close to what I want" and the only problem would be if it fits.

Does that make sense?


you must be an Mechanical Engineering geek.........
Title: Re: Newer kat shocks?
Post by: Chuck on November 28, 2006, 12:34:42 PM
I'm a computer geek, but I happen to know the basics about force and torque and I'm way happier when I understand the things that are keeping my ass off the road.

Happily I found this site to help me understand the mechanics of the swingarm/monoshock business:

http://www.carbibles.com/suspension_bible_bikes.html
Title: Re: Newer kat shocks?
Post by: The Buddha on November 28, 2006, 12:48:01 PM
Then ... get an older Katana shock ... those are small enough in diameter (just a hair larger than the stock ... if that) that it will clear everything. Though short clevise ones would need a little grinding of the steel linkage if your bike had a steel linkage. Long clevise shock did not. or aluminum linkages did not need grinding.
Cool.
Srinath.
Title: Re: Newer kat shocks?
Post by: Chuck on November 28, 2006, 12:52:43 PM
Getting an older katana shock is what I've done on the first GS.  I'll probably do it on the second.  I'm just looking to see if there are other options, because the older ones are older and the newer ones are the same price or sometimes cheaper.
Title: Re: Newer kat shocks?
Post by: The Buddha on November 28, 2006, 02:00:03 PM
Then ... try that aluminum linkage ...
Cool.
Srinath.
Title: Re: Newer kat shocks?
Post by: dgyver on November 28, 2006, 02:47:41 PM
Sometimes you have to just try it and see how it works.

You can compare spring rates from various shocks and match them with appropiate weight front springs.

I have done this with various GSXR shocks but I have not collected any data to back up my applications, other than spring rates of various shocks. Basically I know what "feels right" from years of riding, how tires wear, how the bike handles entering/exiting turns and under braking/excelleration.

I still have not obtained the stock GS shock spring rate. Race Tech and Traxxion could not provided any info other than "too soft".
Title: Re: Newer kat shocks?
Post by: Chuck on November 28, 2006, 02:55:57 PM
dgyver, if you have spring rates, you're way ahead of me.  Can you post what data you have (and where you got it)?
Title: Re: Newer kat shocks?
Post by: dgyver on November 28, 2006, 07:40:58 PM
I have not updated this list recently, been about 6 months ago. I have since acquired a couple shocks which I may need to add their length info.

Most of the rates are from aftermarket vendors websites (ie: Traxxion, RaceTech) and the others are from posts that I came across in my searches for shock info.

****
DISCLAIMER: The shocks listed below may not fit without modifications to either the shock or to the bike. The list was created to compair spring rates and lengths of shocks from other bikes.
****

Shock Spring Rates and Lengths
(Note: lengths are center to center of mounting holes)

1989-06 GS500 292.1mm ___kg/mm (11.5" ___lb/in)

1990-?? GSX600 301.8mm ___kg/mm (11.9" ___lb/in)
1993-01 GSX750 298.5mm ___kg/mm (11.8" ___lb/in)

1990-00 GSF1200S 298.5mm ___kg/mm (11.8" ___lb/in)

1999-02 SV650 339.0mm ___kg/mm (13.3" ___lb/in)
2003-04 SV650 330.0mm 7.7kg/mm (13.0" 430lb/in)

1992-93 GSXR600 ____mm 6.2kg/mm (____" 345lb/in)
1997 GSXR600 ____mm 6.4kg/mm (____" 360lb/in)
1998-00 GSXR600 ____mm 6.4kg/mm (____" 360lb/in)
2001-03 GSXR600 ____mm 8.0kg/mm (____" 450lb/in)
2004-05 GSXR600 332.5mm 7.6kg/mm (13.1" 425lb/in)

1988-90 GSXR750 ____mm 5.4kg/mm (____" 300lb/in)
1991-92 GSXR750 ____mm 5.9kg/mm (____" 330lb/in)
1993 GSXR750 ____mm 6.3kg/mm (____" 350lb/in)
1994-95 GSXR750 ____mm 6.2kg/mm (____" 345lb/in)
1996-97 GSXR750 ____mm 6.0kg/mm (____" 335lb/in)
1998-99 GSXR750 ____mm 6.6kg/mm (____" 370lb/in)
2000-03 GSXR750 ____mm 7.2kg/mm (____" 400lb/in)
2004-05 GSXR750 332.5mm 7.3kg/mm (13.1" 410lb/in)

2001-02 GSXR1000 329.5mm 7.7kg/mm (13.0" 430lb/in)
2003-04 GSXR1000 332.5mm 8.6kg/mm (13.1" 480lb/in)
2005 GSXR1000 325.0mm 8.1kg/mm (12.75" 450lb/in)

1986-88 GSXR1100 ____mm 6.1kg/mm (____" 340lb/in)
1989-90 GSXR1100 ____mm 6.3kg/mm (____" 350lb/in)
1991-93 GSXR1100 ____mm 8.4kg/mm (____" 470lb/in)
1994 GSXR1100 ____mm 8.5kg/mm (____" 475lb/in)
1995-98 GSXR1100 ____mm 8.5kg/mm (____" 475lb/in)

2003-04 ZX6RR 340.0mm 9.7kg/mm (13.4" 540lb/in)
2005 ZX6RR ____mm 10.3kg/mm (____" 575lb/in)
2004-05 ZX10R 338.0mm  9.7kg/mm (13.3" 540lb/in)

Title: Re: Newer kat shocks?
Post by: Chuck on November 29, 2006, 11:49:43 AM
That's cool info, but yes, definitely incomplete.  Surely there must be some reference that parts vendors have with all that data.  You'd never get them to reveal it.  ("Hello, Progressive Suspension?  I'd like some info that I can use so that I can buy stock shocks off of eBay instead of buying your stuff.... hello? ...hello?")