SHOCK for a First Gen: Busa, ZX, or Something Else?

Hello, all. I am contemplating upgrading the rear shock on my first gen SV650, which has casused all kinds of debate over at svrider.com. I am more confused than when I started. Posts have run the gamut. Swap to a Busa or ZX shock -- you'll love it. Penske or Elka is the only way to go. Don't bother respringing and revalving any OEM shock, even a ZX, as it will still be crud. A Busa shock is too short; use one and you'll die a horrible death. (Well, not exactly that one, but pretty close.)

Here's the gist of my original post, and links to the discussions that have followed. Thanks for taking the time to read all this; I would be grateful if someone -- anyone -- can answer any or all questions posed, and maybe bring some clarity to this discussion.

I'm 229 lbs without gear. (Maybe 240 lbs., with?) I keep saying I need to lose weight, but it hasn't happened, yet. No trackdays, although they're not out of the question. Also, no twisties anywhere nearby, although I sometimes travel in seearch of them.

My goal is to swap for a second-hand shock, for as cheap as possible, with as little cutting or fabrication as possible, and without altering the ride height or geometry. So, the short question is, is all of this possible?

My understanding is that I want to come as close as possible to the stock shock length of 338 mm eye-to-eye, and keep the diameter to about 80mm. At my weight, Penske recommends a 700 lb spring, which seems kind of stiff to me, but what do I know?

I've seen people recommend the Kawasaki ZX shocks (ZX6r (a/k/a 636), ZX10, ZX14); the diameters are around 80mm, and the lengths are 338mm for the ZX10 shock, and 340 mm for the ZX6r shock; not sure about the ZX14 shock -- anyone? I think that the real question I have about fitment concerns the placement of the reservoir. Which years for each of the ZX shocks is ideal for a first gen SV? I've seen conflicting reports on which years will fit a first gen without cutting. Are there any that would be a drop-in replacement?

Also, the ZX shocks seem too light. I've seen people write that the stock first gen SV shock is 510 lbs./in., but I've also seen it reported as 540. The ZX6r and ZX10 shocks are only 540 lbs/in., right? And the ZX14 is 543? (Hard to believe for such a big bike, but that's what I've read.) Seems much too light for me; will there be much improvement if I go with a ZX shock?

Now, the Busa shock is sprung at 700 lbs./in., so that seems more reasonable. But it's 330mm, right? That's 8mm shorter, or about 1/3 inch. Enough to matter? What if I used shorter (shorter, right?) dogbones to raise the ride height back up that 8mm? Would that screw up the handling, or am I on the right track, here?

If the Busa shock is the way to go, which year? I assume one from the first gen Busa, as I understand Suzuki made the spring even stiffer for the second gen. But will any '99-/07 shock do, or are some easier to fit? Again, I'm looking for a drop-in replacement, if possible.

I have a line on a member's Busa shock. It's a 2005 with 5,000 miles on it, in good shape. He says that the stock dogbones will work but will cause it to sit lower in the tail than factory. He also says that I would have to modify the pilot's seat mounting bracket on the left side of the bike by trimming about 1/4" off of it so that the resevoir on the shock will clear, but that there is plenty of material to do this. What do you guys think? Will this work as advertised? If I do it, should I change out the dogbones, and if so, to what size?

My other thought is to get a ZX shock that fits as a drop-in, and have it resprung (and revalved?) for my weight. I'd rather avoid the extra expense, but if it's the only way to do this, I'd consider it. About how much would that cost, and who do you recommend for this work?

My thread: http://forum.svrider.com/showthread.php?t=93979

Another relevant thread (it starts with a post from someone with a second gen, but gets to more general issues pretty fast; it kind of implodes at the end -- please ignore the melodrama): http://forum.svrider.com/showthread.php?t=93916

[Mr Speirs]

Zx10R or 6R shock I reckon will be okay for you. Really easy swap. Just have to cut about a playing card size outta the battery box and flip the battery onto its side. Also put a bit of foam to let the battery rest without touching the resiviour.

A spring difference on 30 is quite significant so a jump of 190 to a busa shock is going to be interesting.

I would say get either the zx10r or 6r shock and fit it. See how you feel. If it needs a stiffer spring in it then do it but you may find that the difference is enough to keep it as is.
Either way you have nothing to lose as the zx shock is going to be stiffer than standard.

I believe the shock in mine is a 2005 model zx10r.

Originally Posted by Mr Speirs

I would say get either the zx10r or 6r shock and fit it. See how you feel. If it needs a stiffer spring in it then do it but you may find that the difference is enough to keep it as is. Either way you have nothing to lose as the zx shock is going to be stiffer than standard....

Wow. First response, and, guess what? Here's what I wrote in my thread on the other side of the pond: maybe I should try a stock ZX shock, and if I don't like it, pull it out and have it resprung and revalved to suit me. Keeps my investment low and my options open.

So, maybe great minds think alike, eh?

Can I really put the battery on its side? It's a Yausa model, whichever one they sell for the first gen. Isn't the acid going to leak out or something?

[Biker Biggles]

Gel batteries can run on their side,but I wouldnt put a lead acid one anything other than upright.I think you can get around it by raising the battery a bit and losing the relay tray that sits above it.That gives a bit of space where you cut the battery tray.

[Mr Speirs]

When I say put the battery on its side its actually only sits a wee bit further leant over than where it sits as standard. But I have had to problems yet

Have a look at this thread...

http://forums.sv650.org/showthread.p...ght=GSXR+shock

[mister c]

Dont know if this will help. I fitted an early shock to mine because I got it cheap. I think that the newer version would be easier.
The difference is amazing from stock. Trouble is it then shows the front end up, so you will want to do that after

Here is the link to mine. http://forums.sv650.org/showthread.php?t=113667

Thanks for the links, guys.

I am leaning towards a ZX shock. The spring may be too light for my rider weight on a first gen SV, but isn't it a bit stiffer than stock (540 lb/in vs. 510 lb/in)?

I'm concerned that a Busa shock, at 700 lb/in, may be too stiff (even though that's the spring rate Penske recommends for my weight). I'm also concerned that it's too short, and that the raisng dogbone trick is a poor compromise.

Does anyone know the exact lengths and spring rates for the shocks from each of the ZX6, ZX10,and ZX14, and for the various model years? The only info I have found is that the '04 ZX10 is 338mm and 540 lb/in, and the '03-04 ZX6 is 340mm and 540 lb/in.

Also, I've read that later model year ZX shocks are easier to install because of positioning of the reservior. Which ZX models and which years are you referring to?