Hey Whip! I figured it out! (Stability)

[BeniciaRT_GT]

So in Torrey I was telling Whip that I've never been really comfortable on the GT like the RT when it comes to feeling stable. The GT has always seemed like a very nervous bike. It does as I wish, however it never seems to just stay put. I am always correcting the line I've picked.

 

Well, on the way home while traveling at some pretty good speed through a lot of sweeping turns (never above the posted speed of course!) I noticed how wonderful the GT was tracking and how pleasant the ride was. Then it hit me:

 

The RT wheels are substantially heavier than the GT wheels. I have pics somewhere form earlier this year when I took an old RT wheel and the GT wheel in to get straightened and the weight difference was pretty large. Something like 40 or 50% (trying to make my feeble mind remember, but it was like 12 vs. 18 lbs.)

 

So my theory is that gyroscope on the RT is much more resistant to change from little bumps in the road at speed, and even at low speed the RT has some help, whereas the GT just wants to fall over much easier.

 

Now I understand, and am a fan of, low unsprung weight, however, I think if the GT wheel was heavier, it would be more stable, especially at low and medium speeds.

 

What do Y'all think? Am I full of it or not? (ONLY as it pertains to this narrow subject! I already know the answers for anything else.)

[Matts_12GS]

seems feasible. I just figgered it's cuz your cylinders point the wrong way.

[David]

You're right in that heavier wheels would make it more stable, but also more resistant to turning. Does the GT feel much easier to initiate a lean?

[Quinn]

So, fill the tire with oatmeal and see what difference it makes. Not enough? Use B-B's. Too much, use popcorn. Answer for everything. Just not a good answer.

 

--

 

 

[randys]

So, I am really not overweight, just more stable?

[Whip]

I felt that way on the Tuono with those OZ wheels. I came with some really light tires as well. So I put heavier tires on it and it felt a little better. You may be able to find some heavier tires. 880s for example. Other wise it could just be too much spring and not enough rebound like all the 1200 RTs and 1200 GSs.(IMHO)

 

L

 

 

[EffBee]

So, I am really not overweight, just more stable?

It is entirely unfair to use time-zone advantage to beat another member to the definitive response.

 

Well done!

[eddd]

I'm downing two pints of Tom and Jerry's right now to see if it improves my riding.

[Paul Mihalka]

"I'm downing two pints of Tom and Jerry's"

Is that a new brand? I only know (well) Ben and Jerry's . A good serving may not improve my riding but definitely improves my mood!

[Lawman]

http://www.youtube.com/watch?v=c_f8NunTz5I

[eddd]

"I'm downing two pints of Tom and Jerry's"

Is that a new brand? I only know (well) Ben and Jerry's . A good serving may not improve my riding but definitely improves my mood!

 

 

I guess it's pretty clear I don't eat much ice cream.

 

 

I was wondering why there was so much fur in it.

[BeniciaRT_GT]

You're right in that heavier wheels would make it more stable, but also more resistant to turning. Does the GT feel much easier to initiate a lean?

 

Yes, it is much less effort and an easier turn in. It is just after turn in where I can't ignore the steering input like I can on the RT or several other bikes I've ridden. On the RT I can take my hands off the bars (not quite, but just an 'okay' hand sign, if you will, for throttle control) I wouldn't dare on the GT...

 

So, I am really not overweight, just more stable?

 

Yes, you won't fall down!

 

Other wise it could just be too much spring and not enough rebound like all the 1200 RTs and 1200 GSs.(IMHO)

 

Suspension isn't the issue at this point. It has none!!! At 100K now and the ESA shocks completely gave up about 20K ago. However, although perhaps a little worse now, it has always felt this way.

 

I was wondering why there was so much fur in it.

 

I am using all the restraint I can muster to leave that one alone!

 

 

Thanks for the replies. It isn't so much an issue I was looking to resolve as much as finally figuring out why it feels that way. It's not like it isn't fine the way it is, just much more nervous...

[Heck]

Well, on the way home while traveling at some pretty good speed through a lot of sweeping turns (never above the posted speed of course!)

 

 

So you're saying there were no speed limit signs along that stretch??

 

 

(Sorry I'm late!!!)

[SageRider]

15 Lbs of Dyna-beads ought to fix you right up!

[Bill_Walker]

I certainly don't recall encountering this feeling the one time I rode a GT (about 50 miles or so). Possibilities include tire choice, tire condition, tire pressure, suspension setup, vehicle loading, and perhaps the, umm, interesting history of your particular bike.

[BeniciaRT_GT]

Possibilities include tire choice, tire condition, tire pressure, suspension setup, vehicle loading, and perhaps the, umm, interesting history of your particular bike.

 

no, no, no, no, no, and hunh????

 

I'm not sure what that last one means...

 

This has been from day one, and like I said, it goes away at "higher" speeds.

 

As to tires: I've about had every type and brand that fits on it at some time.

As to suspension: Back when it had one, settings didn't change the feeling much.

Feel free to expand on the last one.

[Whip]

The first gen ESA was junk in IMHO...even when new.

 

Never could get enough rebound.

 

 

[Bill_Walker]

Possibilities include tire choice, tire condition, tire pressure, suspension setup, vehicle loading, and perhaps the, umm, interesting history of your particular bike.

 

no, no, no, no, no, and hunh????

...

This has been from day one, and like I said, it goes away at "higher" speeds.

...

Feel free to expand on the last one.

 

I was referring to the fact that your bike has been down, however lightly, and its many repairs. But if it's been this way since day one, never mind.

[motoguy128]

You're right in that heavier wheels would make it more stable, but also more resistant to turning. Does the GT feel much easier to initiate a lean?

 

The RT OTOH, has a shorter wheelbase and I think wider bars, so that might make up for the heavier wheels in terms of being responsive. The RT might also have a lower center of gravity and differerent weight distribution.

[russell_bynum]

Hard to say (and I haven't ridden a GT so I can't compare GT/RT from personal experience).

 

But...even my CBR and the Tuono will hold a line without outside inputs and both of them have more aggressive geometry than the typical BMW and have less unsprung weight and lighter wheels as well.

 

Have you ridden other GT's and if so, did they have the same behavior?

 

The next question would be for for other GT owners....do they experience similar instability?

 

Assuming there's nothing wrong with your bike most "Bike" problems are actually "rider" problems. For example, the first time I rode a K1200RS, I couldn't make the damn thing turn. I discovered that I was fighting the bike with my upper body. As soon as I would drop my inside shoulder into the turn, and then press and release countersteering pressure to get the bike leaned, it was fine. My CBR600RR is setup for the track and will headshake like nobody's business but only if I'm tight on my upper body while accelerating hard while still leaned over a bit.

 

OTOH, on my Tuono with the Avon Azaro tires and the forks raised up 10mm in the triple trees, when I would lock the front brake the front end would tuck very suddenly and violently. I dropped the forks 5mm and the problem went away. I switched to a tire with a more round profile (Pilot Power) and it was fine (even with the forks raised 10mm). So...it could be a setup issue particular to your bike and that's where it would be good to see how other GT's handle with you on them and then if other GT riders have the same problem.

 

[ShovelStrokeEd]

I agree with Russell. My Tuono is a Factory model and comes with lighter wheels than the standard. It does have some issues with corner stability on exits when hard on the gas in the lower gears. That is mostly due to it trying to lift the front wheel, and often succeeding, while under power. Friend of mine has the bike at the moment and we are working on suspension setup to help with this.

 

A thought and question. Does the GT have a steering damper on the front fork? Reason I ask is that my 1100S had one and it went bad. Started seizing and the bike was exhibiting symptoms similar to what you describe. Tossing the thing in the garbage cured that problem.

 

Might want to check the steering head bearings as well. Notched or seized bearing can cause this.