Let's Talk About "X" - Baby!

[80GS1000]

I love the way it looks. GS bikes with GSXR wheels and forks are so nice looking, and this is a fantastic example.

If you want it to steer faster, you might want to steepen up the rake angle. Newer bikes (Bandits, GSXRs etc) tend to have a short frame, a relatively long swingarm with a relatively steep swingarm angle, short forks, and a steep rake angle which aids in their stability and agility. It also lets them use wider tires without sacrificing agility. When swapping over newer swingarms and forks onto our GS bikes, keeping an eye on the rake and trail numbers is critical to getting the handling response and ground clearance you want.

The best way as you mentioned is to raise up the rear a bit. By jacking up the rear end, you get both faster steering AND more ground clearance. YoshiJohnny and I both did this when putting GSXR 1000 forks on our GS1000s by the location of our monoshock mounts, and neither of us have had ground clearance issues. My rake is at 24.5 degrees right now and it really does steer a lot like my GSXR 750, albeit a tiny bit slower because the GS wheelbase is longer than the GSXR's. Raising the rear also weights the front tire more which makes it feel more planted in corners.

Could you make a couple of steel spacers to bolt inside the swingarm shock mounts to offset and raise the location of the lower shock mounts? This would give you more ground clearance, faster steering, and weight the front tire more.

Those BT021 tires are good sport touring tires, however a tire with faster turn-in and more stick would probably be a Michelin Pilot Power or Continental Sport Attack or Road Attack. I've got 5000 miles on a set of Pilot Powers on the GSXR 750 and the rear looks like it'll go another 1000 miles before hitting the wear bars, which is phenomenal considering how sticky they are. They tip in really fast too, which is nice.

Thanks for the kind words. It handles surprisingly well. The big wide GSXR1100 front tire steers a little slow, but its also very stable. I'm still running the rubber that came with the wheels and I think that when I can spoon on some new BT021 that should change significantly for the better.

I copied Katmans Bandit swingarm and located the shock mounts in the same place that he did which is directly over the vertical weld in the swingarm. If I were going to do it again I would have moved the mount forward about 1/2 inch to raise the rear a smidge, which I think would have sharpened the steering.

What my major concern was during the build was the fact that I had lowered the bike by about 1.5 inches with adding the forks and 17" wheels. I was fearing that I would strike the front of the header on a relatively low speed bump or worse yet ground the center of the header and lift the rear tire. So needless to say I'm extremely cautious when approaching these obstacles and haven't had any problems yet. As I've mentioned, I switch back and forth between my GS and FZ1 all the time and I have to be careful to remember which bike I'm on when the auto pilot takes over in my mind. Bt the way I also haven't had any problems with the engine case guards or pegs touching down in fast corners. I've got the chicken strips on the tires down to about 1/2 inch.

The USD forks have a lot less total travel which helps to overcome the fact that it's now lower. The bike seems more stable in turns, more compliant over bumps just better over all. Is it as good as the 01 FZ1? Not really, but its a ton better than where it was, and my original GS forks had all the upgrades you could possibly do to them. So I'm very happy with the handling.

Visually, what I like the most is the steeper angle of the forks which puts the front wheel closer to the engine. When I look at a stock GS1100, that big gap of space caused by the long forks sticking out so far has never looked right to me. Stock GS almost look like mini choppers to me. When I look at mine now it looks right to me, like a modern bike. I may be the only one that feels like that though.

 

[Guest]

80GS1000,

Clearly you know much more about suspension geometry theory than I do and I appreciate your excellent input.

I'm going to wait for the new tires first before I do anything else to the bike. The other option on raising the rear is a longer shock, like the ones from the ZRX1100 (1/2" taller) or the old Honda 1100F (1" taller), however I've got a lot invested in those old Ohlins but, I've also gotten my moneys worth out of them.

I think we would agree that all bikes feel different to each other in terms of riding preference. My buddy has a Ducati 748 with the high quality Showa forks. We trade back and forth between my FZ1 and his Ducati on long rides (gives his back and arms a break).

That Ducati, which most experts would say is a great handling bike, flat out sucks (to me) from 1-50 mph. Its twitchy, nervous, and difficult to steer due to the riding position, weight on your arms, and clip ons. Heaven forbid you ever get on a dirt or even bumpy road with it, you have to back off to a crawl.

From 50 mph on up the Duc is on rails, a dream bike, that is phenomenal to ride and will make you think your Rossi, and going 25 mph slower than you really are. When its time to trade back I can't get him back off my FZ1, the comfort and riding position overwhelms him and he claims you just have to think where you want to go and it does it at all speeds.

I guess my point is it seems like often with suspension if you make it better in one area you may loose it back in another.

 

[80GS1000]

I agree, some of the race replicas out there are twitchy, uncomfortable beasts made more for flogging around a track at mach looney while dragging a knee versus 300 mile days on the street. That Duke 748 is SWEET BTW, ever have a moment when you think you're Casey Stoner or Louis Capirosi drilling that bike around on a MotoGP track? I'm jealous you've been able to ride one....

One of the things you might find helpful in terms of getting your final geometry set up is setting your bike to the geometry spec of a bike that you already like such as the FZ1. If you're reasonably close to those numbers, you'll get the handling of the bike you like and all the benefits of that borrowed engineering from those teams of mech. engineers with all their PhDs.

For example, take the 2007 FZ1. The rake angle is 25 degrees, and trail is set at 4.3", and wheelbase is at 57.5". I'd imagine the forward/rear weight distribution is in the 50/50% to 52/48% range. If you can get close to those numbers, voila, you have a GS1100 that will do a remarkable impression of the FZ1's handling. I basically did the same thing in copying the GSXR 1000's geometry into my GS1000.

One quick and easy way to check to see where you're currently at in terms of geometry is to use this calculator. I'd be curious to know what your numbers are. The easiest way to check your rake angle is to stick an inclinometer with a magnetic base ($10 at Home Depot) on the steering head of your bike, the rest of the measurements can be done with a tape measure.

Hope this is helpful and not pedantic.

80GS1000,

Clearly you know much more about suspension geometry theory than I do and I appreciate your excellent input.

I'm going to wait for the new tires first before I do anything else to the bike. The other option on raising the rear is a longer shock, like the ones from the ZRX1100 (1/2" taller) or the old Honda 1100F (1" taller), however I've got a lot invested in those old Ohlins but, I've also gotten my moneys worth out of them.

I think we would agree that all bikes feel different to each other in terms of riding preference. My buddy has a Ducati 748 with the high quality Showa forks. We trade back and forth between my FZ1 and his Ducati on long rides (gives his back and arms a break).

That Ducati, which most experts would say is a great handling bike, flat out sucks (to me) from 1-50 mph. Its twitchy, nervous, and difficult to steer due to the riding position, weight on your arms, and clip ons. Heaven forbid you ever get on a dirt or even bumpy road with it, you have to back off to a crawl.

From 50 mph on up the Duc is on rails, a dream bike, that is phenomenal to ride and will make you think your Rossi, and going 25 mph slower than you really are. When its time to trade back I can't get him back off my FZ1, the comfort and riding position overwhelms him and he claims you just have to think where you want to go and it does it at all speeds.

I guess my point is it seems like often with suspension if you make it better in one area you may loose it back in another.

 

[Guest]

That tail is screaming for a little red. I've seen some ES body work where the tail has a small patch of color on the side. I've seen a lot of other blue/white ES/ESD body work with just a white tail. No matter what's suppose to be there i'm trying to fiqure out how to get some red accent on the tail.


Well I was doing some photo chopping to see how some red added to tail would look. I added red triangle with white Yoshimura symbol and GSX1135 in white

Easiest way to do it would be to just buy some red/white yosh decals they have tons on ebay. You may have to magnify the view to see the GSX1135 lettering. Any opinions?

Like it better with some red or leave it alone? From my research I think the top photo is how it would have come stock.

 

[Beaker]

Mate, that is one very special looking GS! Done a great job on her and I reckon she is a pearler.

As far as the red on tail - don't spoil the look with advertising/lettering, just the red and pinstripe as per the front. Have you considered decals that are the same shape as the reflector already on there - maybe 2 of them with both reducing in size.