Two-up suspension?

[copacetic]

Hey everyone.....new here on KR and hopefully going to get my bike in a couple weeks. At least within the next month at the latest if all goes well. I was wondering how the Kats suspension holds up riding two-up? Me and my wife plan on taking some weekend trips and i wasn't sure if I should start looking for some suspension upgrades for the future. I weight 190 lbs. and my wife weighs 115 lbs. Any info would be greatly appreciated.
I've did some searches on the settings for the shocks but really want to know more about things to make the bike handle better. By the way it's an '05 750. Thanks!

[gimmefuel]

Welcome to KR!! I have taken plenty of two up weekend trips and my bike still uses the stock suspension. Never had a problem and the bike seems to handle great! Usually I will have the rear pre-load set at the highest setting while riding two up.

[scottynoface]

What year and size? Most people find the stock suspension more than adequate for two up riding.

[copacetic]

What year and size? Most people find the stock suspension more than adequate for two up riding.

It's an '05 750.

That sound's good. All I've heard and read about Katanas has been good. Makes me feel even better now. Thanks!

[Tmod]

IMO it is not setup well for two up riding, At 190 lbs a 14.3 kg/mm spring would be ideal and the post kat 750 comes with a 10.8 kg/mm spring. So now imagine adding another 115 lbs to the back end and you are really undersprung. Does it ride plusher stock with a extra passenger sure it does but it will be riding close to the bump stop and you will have very little suspension travel left to soak up those bumps.

Tmod

[SKNL2]

Stock set up is very gushy and as Tmod said, that translates to undersprung.

As a cheap fix, I put a Bandit 1200 shock on my 2002 600. It improved things for me, but it does change the geometry of the bike. Research will tell you if it would give you the change you need.

Don't know how aggressive you plan to ride with your S/O on back, but if you do plan on gettin' jiggy wit it, you will want to stiffen things up a little.

[GregS]

I have in the past gotten my wife to ride shotgun on my 04 750. Never had a bottoming issue. Cranking the spring preload up is a real pain on these bikes so not something I'd want to do just for a casual one or two hour ride. I also set the compression damping up to max. It was comfortable for both of us and the handling was acceptable for sport touring type riding.

[landofsong]

My GF and i have done many rides 2+ hrs on my 02 600 with no suspension problems, however I do not get jiggy on it. To see what SKNL2 means by jiggy, you should see some movies of him riding the Dragon, 2s up - impressive!!

[copacetic]

Stock set up is very gushy and as Tmod said, that translates to undersprung.

As a cheap fix, I put a Bandit 1200 shock on my 2002 600. It improved things for me, but it does change the geometry of the bike. Research will tell you if it would give you the change you need.

Don't know how aggressive you plan to ride with your S/O on back, but if you do plan on gettin' jiggy wit it, you will want to stiffen things up a little.

I don't think she would approve of me getting jiggy with it....at least not while we're riding. HAHAHA. I'm pretty sure we're gonna be just sport touring for the most part.

So what are my options if I decide the ride is too squishy if Im going to keep the geometry stock or close to stock?

My GF and i have done many rides 2+ hrs on my 02 600 with no suspension problems, however I do not get jiggy on it. To see what SKNL2 means by jiggy, you should see some movies of him riding the Dragon, 2s up - impressive!!

We've already talked about taking a trip to the Dragon. Probably be next year though. I'd like to see these videos, where do I find them?

[LAsunbird86]

^click on SKNL2's name, and it will let you enter his garage. His ridiculously fast two up riding videos are on there

I have also done a fair bit of two up riding, even through some twisty bits on my 98 600. Stock suspension, and it held up very well for having two people on it (I thought at least), then again, Im about 155 and my girlfriend is about 100lbs, so I dont know how much bigger of an impact that would have on it?
(I also set the rear to its strongest setting, but I hear that the 750's have a bit more adjustment?)

[96katana96]

welcome to the family

[Tmod]

So what are my options if I decide the ride is too squishy if Im going to keep the geometry stock or close to stock?

The best bet if you are usually going to ride 2 up is get a spring in the rear that is stiffer, I already touched on what spring rates are required for your weight. As the back drops down it upsets the balance that the bike is supposed to have when setup properly, Ideally if you will be riding 2 up all the time you would set the suspension up with that and get a spring that will provide the correct sag with both you and your s/o onboard. I don't know how tall you are but as SKNL2 stated you could get a longer shock and with both of you seated it may be at the correct sag and geometry. Another option would be to keep the same shock and get a stiffer spring. IMO the handling of the kat is not the greatest in stock form, Does it handle ok? Yes it does, does it handle like it could? Not with the stock parts. I have worked with Racetech and left them my bike for a couple weeks to develop some improvements to the rear suspension. I would invite you to ask around for those that installed any aftermarket suspension components and get their feedback on what it did to improve the kat in the handling department. On another note most will say that the Kat's handle good but keep this in mind, The best you've ridden is the best you know. So if there is nothing to compare it to how do you know how good it really is.

You would also gain quite a bit by changing the fork springs as well.

Tmod

[justinboyce]

mines set to stock and rides well with me (190) and my wife (125).

[SKNL2]

IMO the handling of the kat is not the greatest in stock form, Does it handle ok? Yes it does, does it handle like it could? Not with the stock parts.

It is a well-known fact that one of the Kat's weak links is its suspension.

On another note most will say that the Kat's handle good but keep this in mind, The best you've ridden is the best you know. So if there is nothing to compare it to how do you know how good it really is.

So very true. Never was this more evident than when I started putting miles on the Gixxer. I still ride the Kat and still like it and I am still reasonably fast on it, but the GSXR is an entirely different world. When I place them side-by-side in riding performance I think of this analogy:
Riding the Katana fast is like trying to drive a deck screw with a hammer. It will do it, it's just not the best tool for the job.

The Katana's suspension is just barely adequate. Listen to Tmod, he knows of what he speaks.

[loudnlow7484]

The best bet if you are usually going to ride 2 up is get a spring in the rear that is stiffer, I already touched on what spring rates are required for your weight.
Tmod

Are you out of the business of rebuilding rear shocks? Building a 98+ 750 shock, that should be right up your alley, no?

BTW- where do you get your calculations for weight/spring rate? Do you have a spreadsheet or something? At a featherlight 135 lbs, what would be my ideal spring rate?