Best Swingarm?

I see lots of folks here have fitted up a variety of swingarms to their bikes. Would like some input from some of you on what works well and what hasn't. As you've seen on some of my other posts, I'm building up a 1982 GPz 750 for AHRMA Vintage Superbike roadracing. Under the rules, I can fit/brace/modify any swingarm, but the bike has to remain a twin-shocker. Of course, welding shock mounts on a single-shock arm isn't too much trouble. Rear wheel also has to be 17 x 4.5", so a complete rear end off a bike using this rear wheel would be a bonus.

Thanks!

Mark Hatten
www.woundedduc.net
AMA Pro #521
AHRMA #52 (#1 for 2007)
WERA Expert #521

I am adapting a zrx12 rear end to my 76 KZ900.It is an easy fit.The rim is 17 X 5.5".I"m not up on the 750 dimentions but if you would like the swingarm,and shock dimentions let me know.

mark1122 wrote:

I am adapting a zrx12 rear end to my 76 KZ900.It is an easy fit.The rim is 17 X 5.5".I"m not up on the 750 dimentions but if you would like the swingarm,and shock dimentions let me know.

The width of the swingarm at the pivot point, and the OD of the pivot bolt would be great! Thanks.

I'll get back to you with #'s.THe pivot bolt on my Z is smaller so I had a sleeve made up to make up the dif.I only had to shave about .080" off the width to make it fit in my frame.If you put out a request for specific parts to the reckers you will be flooded with E mails with prices.

if you are going roadracing id reccomend going no longer than the stock arm;)

You can get a zrx12 swing for about $200. Shocks $125 each.I got the whole rear end with shocks,rim,swing arm,brakes,axles nuts and bolts for $600.

this arm is about 1 3/4" longer than kz.the axle pivet bolt is 20mm.(about 13/16")my kz was 5/8".I had a sleave made. the width is 9 1/4" at the front(can be trimmed) .Shock mounts are 14 1/2" back from the pivot center.The length axle to axle is 21 1/2". I.D. at back is 10 3/4".Shocks are 14 1/8" long ,center to center. If you need anymore info let me now.Glad to help.

Wireman.does the swingarm length actualy change the steering geometry, or how it turns? Or are you refering to ride hieght changes due to more length and laying down of the shocks?

Post edited by: mark1122, at: 2006/12/10 11:18

The longer the wheelbase the slower the bike will turn, alterntively with a longer arm comes greater high speed stability and less step out exiting turns. The modern trend is to use as short of wheelbase and the longest of swingarm possible. For our bikes if maximun handeling is the concern use a set of offset triple trees to pull out about two degrees of rake which will shorten the wheelbase, then you can take advantage of a swingarm that is a couple millimeters longer therby increasing turn in and stability. The best arm that I could find for my Z1 project is the 2001-2003 GSX-R 750/1000 piece it is the same length as the stock piece within a few millimeters and has world superbike winning stiffness. It really is an awesome piece the 750 arm is bare aluminum and the 1000 piece comes powder coated black.

Peace&Love;) Darren

Post edited by: kyradawg, at: 2006/12/10 12:17

Post edited by: kyradawg, at: 2006/12/10 12:23

Best swingarm? Hard to argue with these:


www.win-pmc.com/english/draft/sa/sa-s1.htm
$1,203.58


www.win-pmc.com/english/draft/sa/mono-t1.htm
$670.56


www.win-pmc.com/english/draft/sa/mono-t2.htm
$799.52

Or go here cgi.ebay.com/ebaymotors/Suzuki-GSXR750-S...QQrdZ1QQcmdZViewItem like I did and for $50 + $50 in custom machining get one of these



Peace&Love:blink: , Darren

guitargeek wrote:

Best swingarm? Hard to argue with these:

www.win-pmc.com/english/draft/sa/sa-s1.htm
$1,203.58

www.win-pmc.com/english/draft/sa/mono-t1.htm
$670.56

www.win-pmc.com/english/draft/sa/mono-t2.htm
$799.52

yeah i definately like the 2nd one but those shock mounts are pretty cheesey looking!