Old GS handling limitations

[glib]

So I thought I'd start a new, more general thread with a post from my Works Performance shock rebuild thread and see if I might get some more comments.

I just added Sonic Springs and Race Tech Emulators and it really helped tighten up the front of my GS1100ES. Sag is in range for both front and back (Ohlins in back--haven't charged the Works with nitrogen yet), but...

"Shifting to the realm of unrealistic expectations, I rode on Saturday with a guy on an Aprilia 1000r and I was left wanting in the corners. Though my front is solid in static testing, I could feel wobble when pushing hard in the corners. I?m not sure if it needs some damping adjustment or it?s my lack of skills or the bikes aged design limitations. But the Aprilia looked like liquid as it disappeared out front. After the ride, he said that while following closely behind me, he thought I did well to get the beast on skinny tires around the corners but could see that it was a battle. So am I expecting too much or is there more work to do?"

BTW, it's been suggested that I increase preload in back because I was bottoming out so I promptly broke the spring "keeper" by not using a spring compressor to disassemble when I found the adjustment hopelessly stuck (I am addicted to learning by mistakes).

 

[Big T]

Unless you're dragging the foot pegs/engine cases/sidestand, you haven't reached the limits of cornering yet.
yes, even with skinny tires
Upgrading the suspension is always good and will enhance your cornering confidence

Thanks for the info on the WP shocks, I might have to send mine in

 

[glib]

Unless you're dragging the foot pegs/engine cases/sidestand, you haven't reached the limits of cornering yet.
yes, even with skinny tires
Upgrading the suspension is always good and will enhance your cornering confidence

Thanks for the info on the WP shocks, I might have to send mine in

I'm not dragging anything now--I did with the Works shocks before rebuilding them. I guess I'll get them charged with Nitrogen and give them a whirl.

 

[Tom R]

I think he meant dragging from the lean angle. What kind of tires... swingarm tight, steering head bearings?

 

[Guest]

are you running a fork brace?

 

[glib]

I think he meant dragging from the lean angle. What kind of tires... swingarm tight, steering head bearings?

Yes. I did understand it was a reference to lean angle. I have a sport demon in front--still has plenty of tread but admittedly well worn and cupping. Nearly new Michelin in back (3/4 in "chicken" strips). Everything you mentioned seems tight.

 

[glib]

are you running a fork brace?

I'm not but I do have one from another 1100E. I was thinking about trying it. Do they make a difference?

 

[limeex2]

Yes they make a difference. I'm assuming since you did racetech stuff your steering head bearings are in order. If not, service them when you get a new tire. It is that important. Is there rebound damping, compression damping on your rear shocks? I run my shocks as soft a I can control with those to get a firm controllable ride. Raise your fork tubes in the yokes 10mm at a time until it starts to turn quicker and your comfortable with it. This makes a BIG difference. It takes away the tank like turning that GS's have.

There is lots more to chassis set-up but this is good place to start.

I'

 

[RichDesmond]

Fast street riding is 50% how many chances you're willing to take, 40% rider ability, 10% bike.

If you and the guy on the Aprilia switched bikes, what would have happened?

 

[Sandy]

Fast street riding is 50% how many chances you're willing to take, 40% rider ability, 10% bike.

If you and the guy on the Aprilia switched bikes, what would have happened?

Very well said. I've always said that stepping up to a more proficient bike (or doing lots of mods) won't do anything until you've really learned to ride the one you have.

 

[glib]

Yes they make a difference. I'm assuming since you did racetech stuff your steering head bearings are in order. If not, service them when you get a new tire. It is that important. Is there rebound damping, compression damping on your rear shocks? I run my shocks as soft a I can control with those to get a firm controllable ride. Raise your fork tubes in the yokes 10mm at a time until it starts to turn quicker and your comfortable with it. This makes a BIG difference. It takes away the tank like turning that GS's have.

There is lots more to chassis set-up but this is good place to start.

I'

If you raise the forks on the ES model, it will interfere with the air in the forks?that is, the holes in the tubes will be above the seals that hold in the air. I could try it anyway but what do you think about this?

Regarding the shocks, I hate having to assume anything but the truth is I just assumed the Ohlins were good because they are ?hlins. I only know they have nitrogen pressure because I had that done. Beyond that they could be in need of service. What I can describe is that they seem squishy when I come off the center stand and I feel that they bottom out too easily but the preload is in the proper range.

 

[glib]

Fast street riding is 50% how many chances you're willing to take, 40% rider ability, 10% bike.

If you and the guy on the Aprilia switched bikes, what would have happened?

We will find out when the warm weather comes back (February decided to show up again). I?m guessing I?ll slow down if your percentages are accurate since I won?t push it with another mans bike.

 

[Sandy]

If you raise the forks on the ES model, it will interfere with the air in the forks—that is, the holes in the tubes will be above the seals that hold in the air. I could try it anyway but what do you think about this?

Regarding the shocks, I hate having to assume anything but the truth is I just assumed the Ohlins were good because they are ?hlins. I only know they have nitrogen pressure because I had that done. Beyond that they could be in need of service. What I can describe is that they seem squishy when I come off the center stand and I feel that they bottom out too easily but the preload is in the proper range.

Raising the forks might quicken the steering a bit but will not only reduce overall ground clearance but make the bike a little low on the front. With stock exhaust and good rubber they can actually grind the outside edge of the #4 exhaust header pipe in that configuration. At least on a GS1000 it will and I assume the 1100 isn't much different.

 

[glib]

Raising the forks might quicken the steering a bit but will not only reduce overall ground clearance but make the bike a little low on the front. With stock exhaust and good rubber they can actually grind the outside edge of the #4 exhaust header pipe in that configuration. At least on a GS1000 it will and I assume the 1100 isn't much different.

Really? 10mm will do that? That would be about 7mm at the bottom of the header pipe and at a 45 degree lean that would be 5mm. Wouldn?t a bump in the road be more significant than that?

 

[Big T]

worn tires will create an uneasy oscillation when cornering.
Replace that front tire

 

[Sandy]

Really? 10mm will do that? That would be about 7mm at the bottom of the header pipe and at a 45 degree lean that would be 5mm. Wouldn?t a bump in the road be more significant than that?

Well, my example might be a little extreme but I have done that on a previous GS1000 with track compound tires so yes it can happen .....maybe. 10mm might not be that critical but you do have to realize that under hard cornering the suspension does squat a whole bunch and if the road isn't perfect bumps will eat up some more. Ground clearancewise these old heavy bikes need as much help as they can get and stiffening up the suspension and dampening too much will just transfer the loads to an already wobbly frame. Don't get me wrong though, with a good setup and decent tires these things will handle quite respectably. Too soft they'll squat and scrape like crazy and too stiff they can get wobbly, gotta find that balance.

 

[glib]

Well, my example might be a little extreme but I have done that on a previous GS1000 with track compound tires so yes it can happen .....maybe. 10mm might not be that critical but you do have to realize that under hard cornering the suspension does squat a whole bunch and if the road isn't perfect bumps will eat up some more. Ground clearancewise these old heavy bikes need as much help as they can get and stiffening up the suspension and dampening too much will just transfer the loads to an already wobbly frame. Don't get me wrong though, with a good setup and decent tires these things will handle quite respectably. Too soft they'll squat and scrape like crazy and too stiff they can get wobbly, gotta find that balance.

Ok, I get that. In fact, when I got my bike it had Works shocks (which I recently rebuilt but have not installed), and they were leaking and had no nitrogen pressure (they take 245 lbs). I did scrape the pipes and scared myself before I realized what was needed. What a mess. I forgot what a learning experience this has been.

 

[Carter Turk]

Are the Works 13.5" eye to clevis? That extra 1/2'' out back makes a difference, not sure if yours are that length.
I get that the air fork crossover doesn't allow lowering the forks in the triple clamps much, maybe 3mm or so but I think even that helps a hair with turn in.

I have some ancient progressive springs in my forks, but ditched the 83 forks for older 80-81's as they have some preload adjustability on top and some minimal dampening adjustment on the bottom of the fork legs, which I don't believe the 83's have. No anti-dive BS either.
I think the pvc spacer I have in the forks is about 4" long, and the preload ramp on 2 or 3 of 4.
No air in forks and 250ML of 20W fork oil per leg.

I'm pleased how well the spindly 37mm forks perform doing trackdays, considering their age amonst all the modern machinery usually on the track.
They seem to work, though I do scrape alternator in long radius left handers, might be just my girth.

 

[Baatfam]

What do you mean by "wobble?"
No matter what you do, these old bikes will flex when cornering hard. You should feel the frame bending and moving around. Nothing to worry about, and I've always kind of enjoyed it.

 

[Guest]

my 1100 es has a fork brace, emulators and rt springs up front, ikons in back and roadriders front and back. at track days, I don't notice any wobble and have ground the peg bumps off on both sides....any handling issues are due to my lack of ability rather than the bike.I would say I push about 8.5/10 at the track, not as hard as some, but much harder than I do on the street. I agree, replace the tire and go from there?