monoshock rearend

[80gs1100]

hey guys, does anybody know the best way to rig a monoshock fitting to a gs1100 frame? I have a b12 swingarm already installed with a busa shock. The trouble is finding a way to make the upper shock mount strong enough for the average bump in the road. Any ideas???

Also, I will be mig welding this mount to the frame, if it makes a difference.

[spchips]

Yikes!

I'm pretty sure it's been done, and worked, but the frame flexes enough with the force distributed evenly. Unless the shock is centered on the frame (which i don't think it is) monoshock scares me.

But then I don't know much about practicality.

[makenzie71]

Very impractical. Monoshock bikes came about because the shocks are cheaper and easier to produce (though the over assembly gains complexity)...and because it looks better. In reality, twin un-linked suspensions work better and are simpler...just cost more.

With the GS750 I'm about to tinkering with I'll be installing two CBR600RR shocks with (I think) 225lb Eibach coils for my suspension. I'm having a "T" fitting installed on the remote resavoir, and having the resavoir beefed up a bit to handle two shocks, for my suspension.

[80GS1000]

I asked the same questions on this topic over on OSS, my screen name is boarderline over there, and got some good answers. I'm doing the monoshock conversion on my GS1000 right now, the end result will be a bike that handles and brakes much better than stock.

Are you upgrading your front end too?

The GS frame is actually pretty stiff, a lot of the flex/weave you feel when riding a GS bike leaned over hard at high speed is actually flex in the stock forks and the swingarm, which make them prime targets for upgrades to later gear.

And I don't think it can be said that twinshocks handle better than mono - the opposite is true. There's a reason that pretty much every sportbike made over the last 20+ years has been monoshocked - and it's not cost. Read this: http://www.carbibles.com/suspension_bible_bikes.html

Go take a ride on a newer GSXR in the twisties and compare it to the GS-era suspension - there's no comparison. The GS1000/1100 make great torque and power, especially down low in the RPM range, so you get a best of both worlds scenario by upgrading the suspension on a GS bike to GSXR gear - great torque, comfort and looks from the GS series coupled with the outstanding brakes and suspension from the GSXR series.

[makenzie71]

Making that work I became anything but new to suspension.

Sure, I didn't mention weight, but weight isn't a significant factor. The stock twin shocks on the GS750, for example, weigh 12lbs. The stock suspension on my TLS weighed 15lbs. The suspension on my EX500R weighed 13lbs. The suspension on my R6 weighed 11lbs. That's not really what I would call "weight savings". They cut out a shock but they added a rocker, a beefier frame, a beefier swingarm, and dogbones.

Using the complex modern shocks you'll find today, yeah, you'll be hard pressed to save any weight, but the suspension will be better. Monoshock suspension focuses the stress on a releltively small area. The dual shock setups spread the stress out over a larger area...it makes the action a lot more controlled.

I'm going to fabricate my own swingarm for the rear. Something made of stainless and braced...something that'll look cool haha. The front is most likely going to be Bandit 1200 forks and wheel. I'd like to find a set of inverted forks that would work, and I may end up using TLS forks, but I don't like the idea of having to weld on mounts for the bars.

[80GS1000]

Great looking bike. How does it ride? What single sided swingarm did you use?

You can get handlebar riser kits for all kinds of sportbikes here so you can use USD forks: http://www.spieglerusa.com/cfm/sbk.cfm I'm using the kit for the GSXR 1000 and it looks great. Some Ohlins or ZXR1200 shocks would look trick on the back of a 750.

The gain from going mono IMHO is primarily the handling difference, and it's nice to save 15 pounds from the front end, and probably another 15-20 from the rear end too.

I like monoshocked bikes mostly because they feel more planted going around corners, and the wide radials don't hurt either for braking.

[makenzie71]

Great looking bike. How does it ride? What single sided swingarm did you use?

I use RC31 swingarms...and they've all handled great. The first kit was a bit on the loose side but it was traced back to a rogue bearing in the swingarm. I sell these for TL owners...or actually, as the bike's for sale, I may not be doing it anymore because I always used my bike as a testbed for new parts.

I just accidentally bought a set of '06 GSXR forks and radial calipers...so I guess that's what I'm going to be using.

The monoshock thing, though, isn't going to effect handling alone...and you're not really cutting that much weight. Handling is effected by suspension geometry and you're not changing that...just the boinger. I mean it's your bike and do whatever you want to it, but the monoshock thing is more a cosmetic/cost modification than anything.