learn me, motorcycle shocks in miata

So Ive done a bit of internet searching and of course most the info comes from here so I figured id ask. I know its easy in the rear but tougher to do in the front thats okay im only interested in doing the rears anyways. The car is a 1.6 miata, not much interior, no ps, ect so guestimate 2000lbs maybe 2100. It has take off spec miata suspension which is 700f/250r springs, bilsteins that who knows when they were revalved but they dont leak and dampen the springs well still. Im iffy on the rear struts anyways as I think they need a rebuild more than the front but im also wanting to raise the rear spring rate a bit to help rotate (mainly autox and dd). sooo now that's out of the way I know theres science to choosing the right spring, shock valving hooplah but so far I think it fits the bill, miatas only have an inch of travel anyways and I know some motorcycles have at least that and a bit more. Could it be as simple as finding a heavy bike with a close spring rate and tune from there? Also does anyone have some dimensions of stock miata shocks so I know what to look for? Mounting the stuts up wont be a problem as I have access to machineshop.

Buy some shocks/struts designed for a Miata.

Most m/c shocks aren't designed for vehicles that heavy anyway and you'll have to do a fair amount of fabrication just to get them to fit.

Spec Pinata suspension isn't exactly known for being that good, people use it in Spec Miata because they have to, not because they want to. Spend the money on something like the FM Vmaxx coilovers and spend the time driving the car instead.

Why?

Have known Miata shock supplies dried up?

There are no struts on either the front or rear of a Miata. Buy some stiffer springs for the rear, but leave motorcycle shocks for motorcycles.

^^^ AGREE WITH THE STUFF UP THERE ^^^

The Miata has a really nice suspension from the factory, which is also very upgrade-friendly.

Yes, they are a bit limited as far as shock-travel in the rear. But this has been covered pretty well by FM, as well as a couple other suppliers.

Why try to re-engineer something that already is not really broken, using parts from a completely different type of vehicle?

Bike shocks don't have the travel you need without a lever type suspension design,as others mentioned there's lots of good choices to be had.

I'll get you pics in a bit. 550lb per inch double adjustable aluminum coilovers that require a new lower bushing and slightly drilling out the top mount. R1 or R6. I believe the red springs are the 550lb.

In reply to MrJoshua:

I may have already saved said picture, was that your car? Pretty much what I was going after

Edit, looked back and it is(was?) your car. How did it all work out? Like would you do it again or suggest it? I bookmarked the thread from where I found your photo because you left some good info on there.

It was mine and has gone though a whole cycle of owners until recently SVreX bought it and asked for help from the original build team. The rear motorcycle shocks on the car are the same ones that have been on since we first built the car in '08. They have been great. The trouble has been the fronts. Last year the car took third overall in the challenge autocross with waaay to little spring in the front (550 all around). With that setup the rear could have used more droop because we kept unloading the inside rear and torsens need at least some traction to limit slip. With the 800 lb springs we are using up front this year it shouldn't be an issue.

Cons- no height adjustment an very little droop.

Pro-cheap, good spring rate, simple install, decent ride height out of the box.

MrJoshua wrote: It was mine and has gone though a whole cycle of owners until recently SVreX bought it and asked for help from the original build team. The rear motorcycle shocks on the car are the same ones that have been on since we first built the car in '08. They have been great. The trouble has been the fronts. Last year the car took third overall in the challenge autocross with waaay to little spring in the front (550 all around). With that setup the rear could have used more droop because we kept unloading the inside rear and torsens need at least some traction to limit slip. With the 800 lb springs we are using up front this year it shouldn't be an issue. Cons- no height adjustment an very little droop. Pro-cheap, good spring rate, simple install, decent ride height out of the box.

So the r6 shocks arent height adjustable? or is it the cam ramp style you see on atvs for spring preload. Also in the picture the swaybar is disconnected, was it always run without one? Mine stays disconnected to help my poor little 1.6 vlsd

I'd second (third?) the advice re: FM. After much research and dithering about too many choices, I went with their V-Maxx stage 2 package after riding a car almost exactly like mine that was had it. Huge bang for the buck and exemplary customer service.

In reply to chiodos:

It's the cam ramp pre-load adjustment style. We left the rear sway disconnected for all the autocrosses.

MrJoshua wrote: In reply to chiodos: It's the cam ramp pre-load adjustment style. We left the rear sway disconnected for all the autocrosses.

Interesting, is the reservoir mounted parallel or perpendicular to the shock? Also I see the overall length is +/-300mm, did you have to have a spacer or did it fit and retain a decent ride height? Im at 12.5 or 13in hub to fender now.

And to the naysayers give it up, im sorry, im a broke college student and have less than $200 in my current suspension which is still more than id like to spend on new rear shocks.

Reservoir parallel. No spacers, just the bolt on post mount that comes with the motorcycle shock in the Miata shock mount. You will have to ask SVreX about the hub to fender specifics or I can get them for you at the Mitty.

Could you get your Bilstens revalved and source some cheap springs? We cut one long NASCAR spring for the front this year to save money.

MrJoshua wrote: Reservoir parallel. No spacers, just the bolt on post mount that comes with the motorcycle shock in the Miata shock mount. You will have to ask SVreX about the hub to fender specifics or I can get them for you at the Mitty. Could you get your Bilstens revalved and source some cheap springs? We cut one long NASCAR spring for the front this year to save money.

Thanks, and I could get them rebuilt at $100 a piece or learn to myself and springs are $50 ish a pair. But then I'm in the price of a pair of new konis...kinda trying to be under that price. I'm going to more research into the motorcycle dampers to see if theyre close to what would be suitable for this application.

Digging up an old post here, but for some reason I can't PM other members. Anyway if MrJoshua or Chiodos can let me know if any other development has been done with this it would be much appreciated. I built a Locost with Honda F4i rear shocks for my fronts and Yamaha blaster front shocks on the rear. Worked great, but I never autocrosses the car before selling it.  Oem cycle shocks are cheap enough I may just start experimenting. Looks like I should start with R6 550lb red spring shocks in the rear and something heavier in the front. Thanks for any and all replies!