Rear shock adjusting

[Farre]

I gotten a B6 from ebay, installed and everythin, my first impression is indeed that it's much better, also for sitting position.
But it's too stiff, first of all i looked in the B6manual: the rebound was on setting 4 (highest), so i put that to 2 (spec)
but the preload is also too high, but i don't know how to adjust it, i tried turning it by hand, with a screwdriver but that leaves scratches..
how does one change the thing as it should be done? Nothing written in the manual about doing it

[tomacGTi]

Is it the stepped type of preload or is it two collars with a threaded body?

The stepped type requires a specific spanner to move the collar to the next setting. Kind of like the OEM 400 shock. Your tool kit should have the shock preload spanner or if there's a bicycle shop nearby, there's a lockring tool that will also work.

The two-collar type that has a threaded body uses the same spanner but I usually use a very large screwdriver and hammer to move it because it is nearly unreachable to do it with said spanner. If you're gentle and not neanderthal-like, you should be able to move it without too much drama.

-Randy

[Farre]

it's the first one you describe, didn't know there were 2 types.
Hmmm, i don't have the tool kit, i'll see what i can do.

The previous owner fiddled on the B4 shock, some of the holes ledges are partly bent. I'm not planning to do such a sloppy job with the B6 shock, it's in nearly mint condition.
The change in reload shouldn't affect riding sensation much, would it?
I think the rebound adjustment would be more of a variable in it...

Anywho, thanks Tomac, i'll ride it for the moment like this, it's already so much better than stock  

[tomacGTi]

I'd say drop by a bike shop and ask to borrow/use/buy a bottom bracket spanner. It has the correct "hook" to grab the collar and pull it whichever direction you need it. The big difference between this and the factory one is that the bicycle version is a little longer handle and doesn't have the flat plate the factory one uses for a leverage point.

You should always change the rebound in relation to preload, the shock will not "self-adjust" for more spring energy. If you have too little, the shock will return very quickly and possibly buck you off, if you have too much rebound, it will pack up over bumps and be very harsh.

In theory, with the correct spring rate, the rear should have about 25-30mm of sag and when unlaiden, the back of the motorcycle should not sag. Different strokes for different folks and lots of different opinions, find what works for you and go with it.

http://www.gostar-racing.com/information/motorcycle_suspension_set-up.htm#SET%20UP%20BIKE%20TO%20YOUR%20WEIGHT
http://www.bikesetup.com/

Do a search on suspension in the B4 forums, Jay posted up a ton of other good sites.

Also, the front and the rear of the bike should be as balanced as possible so that the suspension works as a system. Differences in front and rear will affect a bike's handling very negatively. The more balanced front to rear, the more predictable the bike is and the easier to maintain speed in corners, etc..

IMO and through most recent experimentation, it was a huge deal for me. You can read about my exploits in the "PVC pipe thread". YRMV and opinions range but as I said, in personal experience, properly dialed in suspension really makes the bike come alive moreso than jet kits etc.

Good luck!

-Randy

[Farre]

The fun will start soon enough, next week i'm planning to install the GSXR400forks but in the outer tubes of the B4 (single disc / double disc issue) so the front will be also a bit adjustable. After that's done thne i should play with the rear suspension.. makes sense, i forgot about the info Jay gave on this forum, got it now though.

I wonder how it'll be afterwards...

P.S.: a bit off-topic, but does anybody know what exactly those screws on top of the GSXR forks adjust? (rebound?)
Edit: it's preload according to the gsxr400 forums