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Bike Shocks
scootz - 14/10/10 at 06:44 PM

I have two unused BMW (Showa) rear shocks.

They are sturdy buggers, great build quality and as chance would have it - the same length eye-to-eye as the knackered shocks on my car.

Worth a pop - or do the masses reckon the work required to get the damping / spring rates right would be too much of a PITA to make it a worthwhile venture (they cost me less than 10% of the retail cost ).

Ta muchly!


sebastiaan - 14/10/10 at 07:07 PM

What's the spring rate on them? If that is (reasonably) near, chances are the damping will be allright-ish also. Never gonna be ideal, but hey, it's locost!

cosmick - 14/10/10 at 07:07 PM

Not at all, I used some rear shocks on my car very successfully. Often you will find that bike shocks are far superior to a great deal of car ones. they will usually have very good damping and are sometimes adjustable in both compression and rebound. By the looks of the photo, the spring looks like a monoshock set up with rising rate. These can be very strong springs as often the movement of the shock is about one third of the wheel travel so they can be up around the 3-400 lbs rating even though the bike weighs less than a car. If you plan to fit 2 on the back, you will probably have to change the spring, the damping however might be ok.

scootz - 14/10/10 at 07:10 PM

Cheers guys... they are indeed fully adjustable and are about the same physical size as the old 'car' ones that are presently on it.

Just seems a shame to let them sit on my workbench doing now't, or to sell them on again for buttons.

MikeRJ - 14/10/10 at 07:15 PM

quote:
Originally posted by cosmick
so they can be up around the 3-400 lbs rating


Or more than that - the standard rate on an SV650 is 510lbs/inch and plenty of the larger bikes are higher than this. This means the damping rates will be miles out with significantly lighter springs fitted.

The stroke on many of these monoshocks is also likely to be too low for an outboard wishbone application.

[Edited on 14/10/10 by MikeRJ]

scootz - 14/10/10 at 07:24 PM

tony-devon - 14/10/10 at 07:31 PM

I wanted to do this as it was cheaper for me and easier to go to a bike breakers, but a lot of the shocks are sports bike based, think it was R1 shocks that I got hold of, some info online placed them at 700lb springs and on the bikes they really dont weem to move much, due to the rising rate linkage etc

my mates running cbr600 shocks on the back of a build, but got the shocks really inboard to get the leverage on them to make them work. really not ideal

I would however be interested in yours if you wanted to sell them.

my build is a bike trike so got less weight on the back end, and handling isnt paramount, all my normal ones are hardtail anyway with no suspension so any movement is a bonus LOL

SPYDER - 14/10/10 at 07:37 PM

If the range of damping adjustment is similar to that of the R1 shocks we have on our Phoenix ( i.e. HUGE!!) then that aspect will not pose a problem.
As previously stated, the limited travel may be more problematic.
We fitted 250lb springs and got rid of the preload adjustment collar arrangement, replacing it with a solid machined cap.
Our car is trackday only, however, so we can afford to run this somewhat high springrate. We haven't managed to bottom anything out yet, even when two-up.
Maybe we don't try hard enough!
Geoff.

[img][/img]

tony-devon - 14/10/10 at 07:40 PM

thats a beautiful setup you have there, and best of all its orange

scootz - 14/10/10 at 07:41 PM

Looks good Spyder, but sounds like the trial and error process is waaaay above my capabilities!

tony-devon - 14/10/10 at 07:50 PM

scootz you got u2u

scootz - 14/10/10 at 08:00 PM

Cheers Tony...

steve m - 14/10/10 at 08:01 PM

I originlay used Honda goldwing rear shoxs they lasted about 100 miles

If that !!

steve

matt_gsxr - 14/10/10 at 09:13 PM

some useful information here

http://www.peterverdonedesigns.com/05shock.htm


actually his site is pretty cool

Matt

MikeCapon - 15/10/10 at 07:22 AM

Hi Scootz, Looks like your shocks are off a BMW? It depends on the model but the big BMs with shock mounted directly to the swing arm are fitted with pretty heavy springs. 900-1300 lbs/in. So a teeny bit hard for car use. If you have the exact model I may have some more precise data for you.

Cheers,

Mike

scootz - 15/10/10 at 07:52 AM

Cheers Mike... they're from a 2010 R1200R.

MikeCapon - 15/10/10 at 08:13 AM

Scootz, my database runs out around 08 but similar R1200s are all running 900 to 1000 lbs rear springs. I wouldn't shed too many tears if you can't use the shocks. To be honest the Showa units that BMW fit are not the greatest. I used to sell a lot of units to owners of virtually new BMs as the comfort and damping performance of these units is not so good.

If you want to find a bike shock that could fit the car let me know what open length, stroke and approximate spring rate you want and I'll see if any decent OE bike units could do the job.

You could try and sell on the BM units but for the above mentioned reasons there is not likely to be a big queue of prospective buyers.

Sorry to be the bearer of not so good news. I'd hate for you to get a reputation for buying stuff and then selling it off cheap when you find its not really what you want

Cheers,

Mike

scootz - 15/10/10 at 11:20 AM



Cheers Mike!

I've got them on eBay just now for decent money - we'll see how they get on! Hopefully someone from Germany will buy them (they are asking big bucks for used ones on eBay.de!).

MikeCapon - 15/10/10 at 11:26 AM

Good thinking Scootz. In Germany they have a very limited choice in aftermarket stuff due to their ridiculous TuV regs.