I am looking to find out what my options are for the rear shock on an F4i?

I weigh 190lb no gear
I have Ohlins .90 springs in the front, stock valving (working very well)
I ride fairly aggressively on the back twisties, couple of track days per season,
(I do no casual around townriding )
I like set it and forget it suspension settings
I am broke

I cannot afford a good shock set up right now, I have been eyeballing the Ohlins and Penske rear's over on the racing forums, but
going rate is around $350-$450 for a well used 3 way adjustable set up.

If I am understanding correctly, at the very least I can buy an aftermarket rear spring and put on my shock, and not do any other work to it at all?is this correct? cost ~$75 Or, is it mandatory to have the shock reworked? for example: it is suggested to have your forks revalved if you are changing springs, but it is not physically mandatory, just recommended.

If I can simply buy a new spring for now, where the hell do you find them, I have looked everywhere I can think of, but cant locate them. I havent actually
started calling places yet.

any suggestions?

 

Race Tech spring for 190lbs rider
http://www.racetech.com/evalving/Spr...ringType=Shock

 

it says: "no spring type available for your bike" and doesnt give me a 0 spring rate

 

stig at ppsracing.com can do it...

he gave me a quote a few years back to respring the shock and revalve as best he can with the stock shock.

can't remember the price but it was around 200...

then i went baller and bought the second to the top of the line penske...i really don't need 3 way adjustability.

 

That spring rate calculator didnt work for ANY body weight. Did you call them? You might also try LindemanEngineering, good reputation in NorCal. Mostguys here think highly of the 2 way Penske shock,except the really fast guys or the ones with great tuners.Would that be cheaper?

Edit- a working spring rate calculator=http://www.sonicsprings.com/catalog/....php#calculate

 

thanks for the sonic spring calculator, I have used that one before, but I kinda figured it was just for the front springs. not the rear. guess I was wrong.

So, the rear is measured the same as the front? If I wanted to find a rear spring I would ask for a spring rate of .90, just like the front?

so, again, I just want to make sure I am clear---worst case scenario, I can just place a new spring over the rear shock, re-set sag and probably be ok? atleast improved?

 

I remeber doing some research and came across some costom spring makers. It's not hard...all you need to give them is inner and outer measurement, # of coils and gauge of wire. They can custom make your spring to the rate you need by changing one or more of those factors or the metallurgy. In your case Krash, I'd also recommend that you see if you can find a newer shock or if there's another bike's shock that will mount to the F4i.

 

yea...you can mount an F2 shock...and lower the bike...muahahhaah...

from what i recall, there wasn't a direct bolt on option for the spring swap. another spring has to be used and reworked to fit...whatever the hell that means.

 

It's hard to find anything on the web about replacing the rear spring only. Why? I think cause not many people do it.

The rear spring weight is chosen to keep the shock operating in the sweet spot. If your Showa has clapped-out internals you not really gonna find that. Plus, its not that easy to compress that spring and reassemble the shock, imagine a whoops!!! moment and having that burly spring launch itself into your garage.

I'd say this is an ambitious undertaking with an uncertain outcome, though I applaud your spirit. Call around, maybe check out Dan Kyle Racing or Aftershocks out here. A rebuild might be 3x the money and5x the results.

I assume you've set your sagto take advantage of what shock you've got. Some of the track days out here will adjust your suspension and offer advice, sometimes for free.

GL

 

I recall someone looking into revalving the stock shock. It was a band-Aid solution at best IIRC. But I'll let KRASH roger up on this one.