Decided to go searching for spring alternatives for my 900RR shock. I'm probably around 250-260 lbs in heavy riding gear, so I was a little concerned even a 16.8 kg/mm spring would work if I loaded the Givi's up. I found a company in IN, Hypercoils www.hypercoils.com which had a wide variety of free lengths, ID's, and spring rates. 17.0 kg/mm translates into roughly 950 lb/in, so I asked if they had anything close to a 6.5" free length, 2" ID, 950 lb/in spring. They replied that anything over 900 lb/in is automatically a custom, and would run $265/ea (don't remember what min qty would be).

Later, I received an email stating that they had 2 springs left over from a custom order that were 6" free length, 2" ID, 950 lb/in that they'd let me have for $95 ea. I ordered one, and received it today.

Of course, it's 1/2" shorter than the stock 900RR spring, but I figured that with a spring this stiff, lots of preload probably won't be desirable or necessary. If it is required, I can make a shim easily enough. It slips over the body of the shock fine. Hypercoil springs have NO taper to them, fwiw. Each spring has its' tested rate etched into the end.

If anyone want to try to claim the remaining spring, call Diane Baker of Hypercoils at 1.800.365.2645

Cheers.
Chad

Did you install the spring yet??
does it lower the rear of the bike ?? Vs the stock shock/spring?

the price is right I just dont want to have to shim the spring a half inch

If you are willing to fabricate spacers so you can use a 6 inch spring, you may be able to use the same springs that are used on Penske shocks. Mine has a 6 inch spring. (and they have a wide range of spring rates that would work.) I would need to check my shock to get the name of the company that sells the springs. (I won't be able to post this until Monday)
Or, someone else on this board may be able to give you the name of the spring manufacturer right away. (You could call also call Penske, Lindemann or Traxxion and ask them)

The aftermarket shock people all recommend springs quite a bit heavier than the 16.8 that comes stock with your BlackBird.

I just finished installing my new Hyperpro rear shock with remote preload and damping. This setup has a spring that varies progressivly from 16-28 Kg/mm [186-330 lbs/in]. After installation, I noticed that my rear axle is 1/2" further away [wheel is that much lower when on center stand]. I have not ridden the bike yet or adjusted any preload or damping.

The reason I bought this setup is because I ride solo with no bags for day rides, with bags for longer trips and with my wife and full bags and stuff on tours. The weight ranges from 90 kgs-200kgs [200-440lbs] and I wanted easy adjustablility on the rear suspension.
Questions: how will he extra 1/2" effect handling? Should I allow for more sag to compensate for this? Any other comments?

TimXX

It'll steer a little quicker, a lot of guys (myself included) shim the rear for exactly this effect. Leave it be unless that's gonna be a problem :grin: