Rear shock/spring worn? Yes another thread.

[HemiKat]

Before anyone yells, yes I did a search and most of the posts are people going back and forth about which is better performance upgrade. I dont want to run the subject into the ground but I didnt find any "real" awnsers to my questions.

My bike has 46K miles on it and I dont have any idea what has been done about the suspension. I just replaced my front fork seals because they were leaking and I really like how the front end feels, but Im worried about the rear.

1.) When my wife sits on the back the rear sags, alot.... shes not a big girl but shes no runway model either.

2.) With the bike on the side stand I can lean on the bike and the suspension compresses a good bit.

3.) I have never adjusted the rear suspension and Im not 100% how to do so. Dont they have adjuster rings like coil-overs on cars? Do I need a spanner wench to tighten then?

The bike rides good, but I havent ridden any other Kats to compare it to. The expansions seams on the highway hurt my butt, but doesnt that happen on all bikes? How can I yell if my suspension needs rebuilt? If Im in there I think I will upgade to a Bandit 1200 spring. After reading all the past posts I think that upgrade will suit me the best. (Yes arsenic may be right for once.) But anyway opinions are gladly welcome on that subject as well.

I dont do hardcore twisties, but I do occasionally. This bike is normally cruisin through crappy Ohio country roads, and to and from work.... on Ohio's crappy roads. Thanks.

[Tmod]

Before anyone yells, yes I did a search and most of the posts are people going back and forth about which is better performance upgrade. I dont want to run the subject into the ground but I didnt find any "real" awnsers to my questions.

My bike has 46K miles on it and I dont have any idea what has been done about the suspension. I just replaced my front fork seals because they were leaking and I really like how the front end feels, but Im worried about the rear.

1.) When my wife sits on the back the rear sags, alot.... shes not a big girl but shes no runway model either.

2.) With the bike on the side stand I can lean on the bike and the suspension compresses a good bit.
What do you consider a good amount? Without numbers one persons good bit could be different than anothers.

3.) I have never adjusted the rear suspension and Im not 100% how to do so. Dont they have adjuster rings like coil-overs on cars? Do I need a spanner wench to tighten then?
Considering the year of the bike you should have a cam adjuster that will require a spanner wrench or some method to tighten up the preload collar.

The bike rides good, but I havent ridden any other Kats to compare it to. The expansions seams on the highway hurt my butt, but doesnt that happen on all bikes? How can I yell if my suspension needs rebuilt? If Im in there I think I will upgade to a Bandit 1200 spring. After reading all the past posts I think that upgrade will suit me the best. (Yes arsenic may be right for once.) But anyway opinions are gladly welcome on that subject as well.
Arsenic is always right just ask him , Anyway Yes some bikes will feel the expansion joints and some more than others, To tell if your suspension needs to be rebuilt you could look for leaks around the shock or just by feeling the shock when riding and noticing a lack of damping. The stock sealed shock are a very low budget solution to the needs of the suspension and do require replacement fairly soon to maintain proper suspension performance.

I dont do hardcore twisties, but I do occasionally. This bike is normally cruisin through crappy Ohio country roads, and to and from work.... on Ohio's crappy roads. Thanks.

Some of the answer is in your quote, To really say whether the spring is bad or not we would have to know your weight and yes if ya ride doubles a range that the wife is in. Stock factory springs really don't go out that often but it can happen.

As far as just replacing the spring with a B12 spring I don't know if that is possible as the shock length might be different and then you would need spacer and or collars to make it work correctly. Your best bet IMO would be the stock post 750 kat shock or the R6 shock and depending on your weight might require a heavier spring

Anyway hope that gave you some idea on which direction to go, But to get into it we really need weights or combination weights of the rider(s).

Tmod

[HemiKat]

Thanks for the info Tmod.

Well Im 6' 215lbs and she is 6' 160lbs (Shes crazy tall, I know)

We dont ride double very often so if changing anythin will effect solo riding Ill pass.

I must have read the past posts wrong, I thought arsenic recommended the B12 shock because no modifications were needed. If was just a better all around spring/shock.

So a post 750 shock will slip right in and be a heavier spring weight? Or should I just tighter up my currect one?

[rexazz2]

she is so going to kill you if she reads this post

[Tmod]

Thanks for the info Tmod.

Well Im 6' 215lbs and she is 6' 160lbs (Shes crazy tall, I know)

We dont ride double very often so if changing anythin will effect solo riding Ill pass.

I must have read the past posts wrong, I thought arsenic recommended the B12 shock because no modifications were needed. If was just a better all around spring/shock.

So a post 750 shock will slip right in and be a heavier spring weight? Or should I just tighter up my currect one?

Oh you said spring so I mistook that as just the spring and not the shock, The B12 shock will make it sit taller and that will change chassis geometry which may work for you or it may not. It should slip right in but it is not design or valved for the lever ratio of the kat. If ya want a cheap solution you may just want to take that route as it is about the cheapest you will find. Since you do mostly single riding I would suggest a post 750 shock and the spring on that should be good for you or a R6 shock that has a different spring. I revalved a post 750 shock for JayBell and he is at 220lbs and he seems very happy with the ride and performance of that revalved 750 shock.

EDIT: Yeah you can remove the wifes weight now, I know nothing!!

Tmod

[JayBell]

I'll agree with Tmod here.

hit ebay or such, get a post 98 750 shock, and have Tmod revalve it for a heavier rider such as yourself.

I'm 6'4" tall, and 220lbs, and frankly, one of the MOST important things to do with the post 750 shocks is to sit yer but down and SET THE SAG.

actually, its important to do on any bike...but on the Kat, the results were HUGE.

sag is how much the suspension settles with you on it in riding gear and in riding position.

for street use, you should have between 30 and 35mm of sag(about 1.25") on both front and rear.

problem is, on most of the kats you have a notched preset collar to adjust the rear shock... so you can get close, but not perfect... the threaded collar of the post 750 shock, along with the remote compression damping reservoir, and the rebound damping adjustment make this shocks adjustment pretty damn precise in comparison to the stock 600 shock.

add to that the fact that you can get them pretty easily on ebay between $50 and $100 or so, AND tmod can revalve the shock for your heavier weight, you get a better performance shock for a really cheap price.... yeah, Ohlins is a better shock, but $500 better? Not after Terry gets done with the stock rebuild.

for the front, you have to change the springs and adjust the length of the spring spacer tubing inside to adjust the preload... thats harder all around.

but it sounds to me that you'd really benefit from a revalved post 750 shock, and actually sitting down to set your suspension up correctly.

when i did it, the back end felt like it was a brand new bike, much more feedback from the rear, no squirmy feeling on acceleration, no mushy diving feeling going thru corners, no wishy washy sensation lik the backs going to slide out, no more bottoming out.

An added benefit of setting the rear preload right for your weight is it gets the right ssuspension geometry going... so in addition to the above benefits that i got from the back, the stiffer PROPER adjustment also made the front end different... more lively and more maneuverable, as the back end wasn't taking necessary weight needed to properly load the front end.

also, the compression damping adjustment makes a big difference, as can the rebound damping on the bottom of the shock... you can play with those, but on my rebuilt shock, I left the rebound set to 2(stock) and have the compression damping on the reservoir set to One full turn OUT from closed ( I prefer a harder ride, if you get suspension chatter in bumpy curves, reduce the compression damping)

So overall, I feel my bike is MUCH more solidly planted in corners, which brings better confidence overall, and a better ride experience in the twisties. on open road, expansion joint WHACK is a thing of the past, and the suspension cycles much more smoothly on bumpy roads.

good luck, See Tmod in the Chatbox if you need help.

[md86]

So a post 750 shock will slip right in and be a heavier spring weight? Or should I just tighter up my currect one?

Yup . Had one on MY pre750 before I got the Ohlins . My "old" 98+ shock is actually in a box getting ready to go to T-mod . Only sucky part is if you wanna adjust the preload , you gotta take off the rear plastic to get to it .

[awsnap]

I've really gotten tired of my suspension so I'm researching today. I KNOW I need a front suspension fluid swap/rebuild. Occasionally as I'm riding the forks get extremely soft and make for scary horrible turning as you can imagine. Like turning on marbles. So, I'm thinking new fluid and seals for S&G's. There are NO leaks. And yes, it will go back to stiff at some point during the ride....

I ride two up almost all the time. I weigh 150 and she MIGHT weigh 135. When I take a turn and there's a small crest between the front and rear wheels, I bottom out on the exhaust. Thankfully I don't have the bottom fairing on, otherwise, it'd probably be in pieces. This sounds like a spring problem, not shock, although, that could use a service too. I have the spring adjustment at 5 and the damper on hard. Why does this happen?

From what I've read I can use a post 750 (I have a pre 750) spring and shock. And does the front end seem like a simple fluid swap?

[Tmod]

I've really gotten tired of my suspension so I'm researching today. I KNOW I need a front suspension fluid swap/rebuild. Occasionally as I'm riding the forks get extremely soft and make for scary horrible turning as you can imagine. Like turning on marbles. So, I'm thinking new fluid and seals for S&G's. There are NO leaks. And yes, it will go back to stiff at some point during the ride....

I ride two up almost all the time. I weigh 150 and she MIGHT weigh 135. When I take a turn and there's a small crest between the front and rear wheels, I bottom out on the exhaust. Thankfully I don't have the bottom fairing on, otherwise, it'd probably be in pieces. This sounds like a spring problem, not shock, although, that could use a service too. I have the spring adjustment at 5 and the damper on hard. Why does this happen?

From what I've read I can use a post 750 (I have a pre 750) spring and shock. And does the front end seem like a simple fluid swap?

Using the post 750 shock will not solve your problem as you will still need more spring then that has, You should need right around a 14.3 kg/mm spring for your 2 up riding, keep in mind that when riding solo it will be stiff without backing the preload back down a bit. I would also recommend new fork springs for the front as well.

Tmod

[awsnap]

So because I'm looking to move to a different bike in the next year (I think I said that last year), I don't want to spend an arm and a leg on springs. What rear spring or spring/shock can be swapped in to meet that need? In the front, am I f'ed? Will a preload mod help that?

Also, in the front, if I'm gonna swap out fluid, are there parts I should replace beside the oil and dust seals? Can the rear be serviced? I guess I should RTFM....

[Tmod]

So because I'm looking to move to a different bike in the next year (I think I said that last year), I don't want to spend an arm and a leg on springs. What rear spring or spring/shock can be swapped in to meet that need? In the front, am I f'ed? Will a preload mod help that?

Also, in the front, if I'm gonna swap out fluid, are there parts I should replace beside the oil and dust seals? Can the rear be serviced? I guess I should RTFM....

If you don't mind a higher seat height get a busa rear shock as they are at 13.4 kg/mm if memory serves correct. Also on the front you can increase oil to make it stiffer, and add a spacer under the fork cap.

A new spring would be right at $80.00.

Tmod

[awsnap]

I looked for the thread that basically called the Busa spring a piece of crap. Honestly, I can NOT afford to gain 2", or even 1" in the back. And AFAIK, there aren't lowering dogbones for the pre 750. Right?

I also can't find a pic of a comparison of springs, but it had the R6 spring there and it's the same height. Does that fit my requirements? Also, what strut do I pair with it? Post Kat?

[Tmod]

I looked for the thread that basically called the Busa spring a piece of crap. Honestly, I can NOT afford to gain 2", or even 1" in the back. And AFAIK, there aren't lowering dogbones for the pre 750. Right?

I also can't find a pic of a comparison of springs, but it had the R6 spring there and it's the same height. Does that fit my requirements? Also, what strut do I pair with it? Post Kat?

Ok if you can't afford to gain any height here is what I would suggest, Either a R6 or Post 98 750 shock with the correct spring for you, I can get the spring for you at close to dealer cost which was the $80.00. I can also supply a shock as well. I have both here.

I could just put the heavier spring on the post 98 750 shock and send it on it's way. Using the R6 shock you need a $50.00 adapter to run the aftermarket springs.

Let me know if this is the direction you would like to go.

Tmod

[awsnap]

What do you want for the post shock and the correct spring? Also, is this totally going to blow my solo riding? I still should be able to adjust the preload right? I assume the post kats have that, and dampening.

As far as the front is concerned, I'll swap the fluid to 15W and add a spacer. Seems like everyone likes that. I'll reask the question, are there other parts besides the four seals that I should replace while I'm in there?

[Tmod]

What do you want for the post shock and the correct spring? Also, is this totally going to blow my solo riding? I still should be able to adjust the preload right? I assume the post kats have that, and dampening.

As far as the front is concerned, I'll swap the fluid to 15W and add a spacer. Seems like everyone likes that. I'll reask the question, are there other parts besides the four seals that I should replace while I'm in there?

I will PM you the price on the shock and spring.

Yes you will be able to adjust the preload with the threaded collar and being that you will need to adjust the preload fairly often I made some threaded adjuster collars that use a rod to turn it as that makes it easier to adjust the preload. Image is below. As far as having your cake and eating it to, It just doesn't exist. Yes when riding solo it will be stiffer than if it was set up for 2 riders. Being that you want to change back and forth I would probably suggest a 13.4 kg/mm spring as it is right in the middle.

The post 750 shock has threaded collar for preload, 4 position rebound and a high speed compression adjustment as well as remote reservoir.

As far as the front since you have a pre you could just drain the oil as you should have the screw at the bottom of the forks and refill with some new stuff, If your seals are not leaking that would save you a bit of money.

Tmod

The collar on the left would be the one I would suggest and it is hard anodized to prevent wear to it and you see the set screw and the holes for the rod so you can adjust without using a pliers or spanner wrench.