Monoshock Upgrades

[Dartanion]

Does anyone know if newer GSXR or SV650 monoshocks will fit a pre-98 Katana? Looking at the fich the pictures look similar, but I can't verify dimensions. The GSXR may need a frame modification to fit due the the external can at the top, but the SV looks like a direct swap.

Would the newer shocks handle the extra weight of the Katana's or will they perform poorly due to the added weight?

[floxera]

SV650 rear shocks wont fit. I've heard rf900 shocks work. The ideal replacement shock IMHO is a 1990-1992 gsxr 1100. It will bolt right up to your kat no problem. Any gsxr 1100 shock 89 or older bolts to the linkage or dogbones differently and will not work on a kat. Any gsxr 1100 shocks 1993 and newer will not fit because the diameter of the spring is to large to fit through the swing arm. To further complicate matters many shocks on ebay are mislabeled. You may think you are buying a 1992 but It could be a 1993. The spring size difference is so small I cant tell the difference unless the shocks are side by side.

You could also buy Gsxr 750 1990-1992 but a Katana weights about 30 more pounds so if you are a heavy rider or you are riding 2 up the spring could be overloaded. But may people have 750 shocks and say they are great, I just think the 1100 is a little better match.

I bought 4 different Gsxr shocks to find out this info. All the shocks I bought needed to be rebuilt after all they are 12+ years old. I have been looking around at rebuild prices. It will proably cost around $130 shipped. That may seem expensive but a new kat shock for a pre98 cost about $800.
I still have yet to get my gixxer shock rebuilt. I did buy a 98+ rear shock a (2001 to be specific $30) shipped. I always wondered if 98+ shocks would fit in a pre98 Kat. Turns out they fit perfectly. Both shocks look to be exactly the same length, I couldnt measure them because the pre load settings were set different. Anyone try to change the preload while the shocks off the bike? I couldn't do it. Still they are almost exactly the same length. If your on a budget putting a late model 98+ shock in your pre98 Kat is the way to go. If you are looking for increased performance go with the gixxer shock, but expect to have it rebuilt.

Would the newer shocks handle the extra weight of the Katana's or will they perform poorly due to the added weight?

The pre98s are 20lb lighter.
98+ 600s are 458lb
pre98 600s are 438lb.

[Dartanion]

What is different about the SV shocks that makes them not work? Length, width? Could it be modified?

[floxera]

I'm not sure why the sv650 shock won't fit. I read it on KP.com and dismissed it as an option. I just assume a Kat was much heavier than a sv650. It might work with some modifacation. The sv650 stock suspension is nothing special. My take is why mod an sv650 shock when you could get equal performance or better(wieght factor) out of a direct bolt on $30 used 98-02 kat rear shock.

[damic]

I don't know about dimensions but the Kat is too heavy a bike and the SV shock is not rebuildable. You wouldn't want an SV shock any way because preload is the only adjustment it has. That makes the stock Kat shock a step up. Many SV owners swap in a 98 GSXR shock for a cheap upgrade. That is what I did when I had mine.
Damic

[Dartanion]

The newer Kat shocks have preload and damping? I thought they got rid of that in the newer models.

[floxera]

I have a 2001 600 shock with 1-7 preload and 1-4 rebound damping.
The 98-02 750 shocks adjustable preload, rebound damping, and compression damping.
I dont know about 03-04 kats.

[Waltari]

As stated the 90-92 gsxr1100 shocks wi;ll bolt right up as will the 90-92 GSXR750 shocks. The RF900 shocks are not a straight botl on a sthe upper eye is slightly wider than the upper katana mounting point.

That being said, I think the RF900 shock would be more of an ideal replacement because it still has the adjustability of the GSXR shock but is sprung for a heavier steel framed bike. I would use the RF900 shock and simply file the upper eye down slightly. It truly is just barely too big and there is plenty of room to file it and make it fit, it just doesn't slot straight in untouched (if that makes sense).

[Dartanion]

Thanks for the info guys. If all goes well I plan on having the bike apart to the point where the frame is separated, meaning everything is apart.

Waltari, how much wider are we talking here, you have the RF swingarm, do you have the suspension as well. Is this a matter of .100" or 1/2"?

Whoops: Also, Waltari, are the RF swingarms aluminium, and how much is needed to make it fit?

[Waltari]

Thanks for the info guys. If all goes well I plan on having the bike apart to the point where the frame is separated, meaning everything is apart.

Waltari, how much wider are we talking here, you have the RF swingarm, do you have the suspension as well. Is this a matter of .100" or 1/2"?

Whoops: Also, Waltari, are the RF swingarms aluminium, and how much is needed to make it fit?

I don't have it in front of me, but I know it was minimal (maybe 1/16-1/8th of an inch)

As far as the entire RF900 swingarm/rear end. The pivot point is actually narrower than the katanas but the problem is the lower subframe rails. The swingarm flares out too quickly beqcause of the larger rim and it makes contact with the kats lower subframe rails. Basically, imagine your frame from the part where the swingarm pivots bolts through the frame, now cut off everything behind that and start from scratch...thats whats necessary to make it fit.

[Dartanion]

As far as the entire RF900 swingarm/rear end. The pivot point is actually narrower than the katanas but the problem is the lower subframe rails. The swingarm flares out too quickly beqcause of the larger rim and it makes contact with the kats lower subframe rails. Basically, imagine your frame from the part where the swingarm pivots bolts through the frame, now cut off everything behind that and start from scratch...thats whats necessary to make it fit.

Thats fine, most of that is in the plan if I get that far anyways. If thats the only issue, then all I have to do is properly brace the rear subframe.

[Waltari]

As far as the entire RF900 swingarm/rear end. The pivot point is actually narrower than the katanas but the problem is the lower subframe rails. The swingarm flares out too quickly beqcause of the larger rim and it makes contact with the kats lower subframe rails. Basically, imagine your frame from the part where the swingarm pivots bolts through the frame, now cut off everything behind that and start from scratch...thats whats necessary to make it fit.

Thats fine, most of that is in the plan if I get that far anyways. If thats the only issue, then all I have to do is properly brace the rear subframe.

No, properly bracing the subframe isn't all you'll need to do. The Kat footpegs/rearsets are part of the lower frame rail so you'll likely have to convert to gsxr style rearsets. And since there are no real solid mounting points for those rearsets you'll have to drill the frame and weld in slugs that you can drill and tap so you have a solid place to mount them.

Then you'll need a set of these to be able to use your stock kat axle with the RF900 arm

and you'll also need to fabricate custom offset dogbones to make the suspension work since the upper shock mounting location on the kat places the shock at a slightly different angle than the RF900 and if the offset bones aren't used the shock will make contact with the swingarm.

You'll also need the RF900 rear rim, cush, and an aftermarket sprocket (since the RF900 came with one with too few of teeth for proper gearing on the 600cc Kat motor, you'll also need the brake mount, a new caliper/master and line. I'm sure I'm forgetting something but you get the idea...not exactly a "bolt on mod"

[sadrik]

Just want to clarify, this all applies to both pre-98 Kat 600 and Kat 750s?

[md86]

Can I tell if the shock I got needs to be rebuilt BEFORE I get it on the bike ? I'd hate to put it on and then have to take it back off again . Bought a '90 something 1100 shock off E-bay that supposedly will fit without modification .

[floxera]

I've bought 3 different gsxr shocks all from the early 90's all of them need to be rebuilt. I don't know if there is a way to test them at home. I always bolt them on and go for a ride. It only took a couple bumps and one corner to determine how poor the shocks I bought were.

GoodLuck