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Snowscum
Posted on Friday, September 21, 2007 - 02:50 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Since Buell stays with the short swing arm, is it more stable than a longer one like on the FZ'z?
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Snowscum
Posted on Friday, September 21, 2007 - 06:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Why I ask is because a friend of mine gives me so much crap about owning a Buell. Saying that a longer swing arm is the better choice because its more stable in turns. Saying thats why the gp bikes run longer swing arms. I have no response to this mostly because this is the first bike Ive owned since the 80's. I think its pretty stable since I am no racer. Do you guys have a response I could give? Is he full of himself?
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Thespive
Posted on Friday, September 21, 2007 - 07:22 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Ask him why the 12R won a shootout for title of best handling bike.

--Sean
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Snowscum
Posted on Friday, September 21, 2007 - 07:25 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

What mag was that in?
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Lost_in_ohio
Posted on Friday, September 21, 2007 - 07:34 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

The article was linked....Give me an hour or so to dig it out of the knowledge vault
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Tom_b
Posted on Friday, September 21, 2007 - 07:37 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

He is full of himself. I'm no racer by any means, but I can take many a turn faster than my friends who have way faster bikes that are longer wheelbase. Put an equally capable rider on a stock buell and a stock whatever and the buell will out handle. When i can confidently take 45 a mph turn at 90+ that is a bike that handles. I've rode few others that i feel i can safely do that.
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Lost_in_ohio
Posted on Friday, September 21, 2007 - 07:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

found it

http://a1264.g.akamai.net/7/1264/1354/a3055969211e 9e/www.buell.com/en_us/news_events/pdf/BikeTop50.p df
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Metalstorm
Posted on Friday, September 21, 2007 - 08:45 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I think the length of the swingarm depends on the chassis design and weight bias.
I'd bet a swingarm too long for a certain bike would be just as funky as a swingarm too short.

That's just a guess, I'm no engineer.
Buell knows exactly why they do things the way they do. Because it works : )
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Wile_ecoyote
Posted on Friday, September 21, 2007 - 09:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

The idea of the longer swingarm came about because of wheel spin and traction issues when leaving a corner. In other words, you friend has an enlarged ego. Some bikes have certain weight bias that necessitates a long swinger. It helps put the bike in sort of "launch" mode that allows the bike to motor out of the corner. A Buell does not need that type of swingarm because our power is tractable. Meaning it keeps traction without having to bias the weight on the rear. This IN MY OPINION makes for a much better streetbike. I have a GSXR1100 with lots of power but to access it, I have to really rev the motor. It makes for an all or nothing type of situation. As far as power. Now my Buell with a stock motor makes just as good of power actually better because I can use it. Its always right in the sweet spot for on the street. Most of the jap bikes will NEVER be ridden to their full potential on the street. Not healthy as you have to crank the snot out of them to reach a peaky powerband. The Buell motor has tractable, useable power throughout the rev range and has yet to dissapoint me. Yes, I get killed in the straights but, most cats around here have nothing on me in the corners. I'm relatively new to my Buell but dont see me going back. (anyone want to buy a fire breathing GSXR1100?)
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Snowscum
Posted on Friday, September 21, 2007 - 09:22 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Here is his response. haha
BTW I have a Uly and my front tire is cupping and he said that a cupped front is a bad sign of things to come. He is no naive.


"Like I said---I'll buy you lunch if you promise to stop sending me this shit.

I was going to ask you if you wanted to go on our ride this weekend, but I know that your tires are your forks are junk, and your ergonomically correct buelly only allows you to ride about 100 miles a day.
And that doesn't even include all the bad remarks you made about my new bike.............

Buy a real bike and get with the program!
It's almost impossible to learn the proper techniques of riding with a bike that you don't have any confidence in.
Or we could go on a ride some day and you can show what a great bike you have-------just name the canyon and I'll follow you. "

The only remark I said about his new fz1 was the can is fugly.

Thanks for the comments about the swing arm. I agree with you guys but some people have it about Buell.
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Wile_ecoyote
Posted on Friday, September 21, 2007 - 09:36 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

The FZ1 is a remarkable bike. Ask him about the fuel injection problems they have. I have seen it first hand. Abruptness and wonky type action. How does he deal with it. My point is no bike is perfect. It takes a rider to make it good. We are talking apples and oranges if he is on a FZ and your on a Uly. Not meant for the same thing other than being a motorcycle. Is he a good friend? If not, his comments will get old and distasteful as time goes on. Maybe find a new riding partner. Or better yet, let him ride your so called unsuperior bike. Ask to ride his and see if the bike will make you the next Wayne Rainey. I dont know you but, I doubt it. Your forks are not inferior, maybe the setup is or air pressure. Try firming up the spring in front to take some weight off it. Check the air pressure. Most of all, dont take his comments to heart as he will in time have issues with his bike too. Back to task, the swinger on his FZ is a copy or the same on the R1. That bike has a peaky powerband. Meant to aid in tractability and possibly a look factor. Ohhs and ahhs mean nothing to me as I'm trying to learn to ride the best I can. At one time they did, not now. (older and wiser, well older anyway) LOL!!!
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Coal400
Posted on Friday, September 21, 2007 - 10:33 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I am not an engineer either but I'll comment anyway : )
In addition to what's already been explained about weight distribution, I think the longer swingarm will have a larger, more gradual, arc (better geometry). This will lessen the the fluctuation of wheelbase when the suspension is active. The suspension travel is also running more perpendicular with the road surface thus making the suspension action more "linear" and lessening the impact on geometry.

The shorter wheelbase allows for tighter handling - this is signature Buell and I'm sure everyone knows this. (its actually common sense)

on a side note: I would be interested in seeing the difference in length between the rear axle and swingarm pivot point on the 1125R and the XB std/long models.
I don't have the specs but I'd bet the 1125R front axle to pivot is shorter than the XB's. I also bet that the increase in overall wheelbase is also less than the increase in swingarm length, when comparing the 1125R to the XB's. I think this is why Buell designed the 1125R engine to be a stressed member of the chassis - to accommodate an even longer swingarm while keeping the wheelbase short. Moving the engine forward also allows for a longer swingarm, but adds additional benefits by putting more weight on the front wheel for stability.

So I guess I would ask your friend to qualify his statement... Ask him why the swingarm length really matters on his street bike.
Really, the impact is going to be dependant on the application, but you don't have to bring that up. If he continues to go on then he's, as you put it, full of him self.
Maneuverability can sacrifice stability, but sometimes the tradeoff is worth it.(i.e. aircraft design)
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Snowscum
Posted on Friday, September 21, 2007 - 10:34 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Well the front is always been a sore spot. I was waiting till the 10k to spend the money on 07 springs. It could be those stock dunlaps. Who knows.

He is my old snowmobile buddy and has been riding cycles for 30 odd years. Me = 9k on a Uly. So I am still pretty new to this sport.

The swing arm comment kinda threw me for a loop. For drivability I think the shorter swing arm wins. But at high speeds it would make sense to have a longer one to dampen more of the force. I guess it matters where most of the motor weight is. Just rambling.

It would be nice to fit on a stock fz but the Uly has way more room. Feels pretty ergo to me. It wouldn't matter if I was in a car, sitting for long periods in a car still kills me. Lol Its a pain getting old.

I guess Ill add this. He is a aerospace engineer.
A smartass one but a dam good engineer.

(Message edited by snowscum on September 21, 2007)
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Wile_ecoyote
Posted on Friday, September 21, 2007 - 10:54 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Thanks Coal, filled in the holes that I couldnt quite explain. I am no engineer either. I could be totally wrong about what this guy is trying to qualify his Yamaha as such a world beating end all bike. I tend to get alittle peeved myself when asked why a Buell? You have to ride one to understand. I have had the good luck to own 16 bikes in my 40 years of life. The Buell does it for me. I believe in them and Erik. Thats not to say the others are good even great. I know my bike has a soul all its own. It happens to talk to my soul more than the others. I'm yet to see Mr Honda or the other company owners deal with the public in a manner close to what Mr Buell has done. I not only find it incredible but inspiring. As for the aerospace engineer, he may be pulling your cord a little. Just thought you should know whats up with that long swinger. OKAY I'll step off the soapbox for tonight but, will ask for your vote in the upcoming primaries.......LOL!! Wile E. for gubner. PEACE OUT YA"LL!
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M1combat
Posted on Friday, September 21, 2007 - 11:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Coal is more correct I think.

Take into account the rake of the forks and the angle from horizontal of the swingarm...

Now realize that the swingarm proscribes an arc where the forks travel straight.

There are two important issues regarding NOT CHANGING THE WHEELBASE of the bike as you go over bumps. One being how closely the swinging arm is to perpendicular to the forks. That's the most important thing once you have a swinging arm that's "long enough". The second most important thing has to do with the radius of the arc (or swinging arm length). Keep in mind which one is more important...


The Japanese bikes "need" a longer swing arm because they use a more relaxed rake (23-25 degrees) so the swing arm is farther from perpendicular compared to the forks.

The XB uses only 21 degrees of rake so it's easier to point the swing arm in a direction that's more perpendicular to it.


Once you have all that in your head : )...


Realize that because the front pivot is higher than the rear... a shorter swing arm makes for a steeper angle (compared to the ground). This aides in anti-squat coming out of turns : ). Plenty of good reasons to use a shorter swing arm... but plenty of good reasons to use a longer one.



The point : )?


Use the swing arm that is the correct length for the rest of your geometry. The FZ1 and the XB both have that : ). Your friend would do well to open his mind and maybe read a book or two before he decides to tell you that your swing arm is too short...


Point out the fact that the rest of the geometry is different (and a parent of it won best handling bike of the last 50 years from Bike Magazine...) from his FZ1's so why in the should any rational person think that a swing arm that's the same as the FZ1's make the Buell handle better (or the FZ1 for that matter : ))?



That said... No offense... but the Ulysses isn't exactly the best track/deep canyon road carver that Buell makes. It DOES handle well though... just not quite like a "proper" sport bike like the Firebolt.


Wile...

I think you were referring more to anti-squat. Anti squat is helped with a steeper angle on the swingarm (or to a lesser extent a longer swingarm). Anti-squat helps to keep the rear from "squatting" coming out of turns. Squat makes the bike run wide. If you don't squat and make the bike run wide you can use more throttle to make it "run wide" (aka exit the turn).




Hope that helps.
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Xb9er
Posted on Saturday, September 22, 2007 - 08:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Get used to these comments, but get in the habit of saying, "Lets go for a ride."

There is a guy I'm in the guard with(busa rider) says the same stuff. He has yet to agree to go for a ride with me. Satisfaction at its greatest.
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Jlnance
Posted on Saturday, September 22, 2007 - 09:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I was waiting till the 10k to spend the money on 07 springs. It could be those stock dunlaps.

You've still got the Dunlops? As soon as you change your front tire (to something else) you will note a remarkable improvement in the bikes handling, particularly if you have run it long enough to cup. The front dunlop will cup long before it gets down to the wear bars and it does affect handling. If you want an interesting experiment, get on a straight road, take the bike up to 55, and then take your hands off the bars and let it coast down. See if you get an head shake somewhere on the way down (the bars shake, the bike doesn't seem to.) Thats the worn tires.
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Akbuell
Posted on Saturday, September 22, 2007 - 12:09 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Stability, or lack thereof, is a function of the overall design of the machine, as expressed by the desires of the designer. When an engineer puts pen to paper, he (or she) has an idea of intended use, wheel base, engine type, price, weight, yadda yadda. Each design element influences the others, and is reflected in the finished product.

Sounds like class envy, the old Ford vs Chevy thing. If longer is better and more stable, ask your experienced friend why his bike DOESN'T have a 3-4ft long swingarm like hillclimb and drag bikes. And given his "experience", he should know that tire cupping is a product of tire design and pressures. Armed with the replies others have made, give him these facts, and perhaps consider new riding partners. Ride safe, have fun!!
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Lost_in_ohio
Posted on Saturday, September 22, 2007 - 12:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

If your friend keeps calling your bike crap...He obviously isn't much of a friend.

Besides isn't a Uly a different bike than an FZ. Now if he wants to compare apples to apples how about the 1125 vs. his FZ.

I ride with Harely guys, gsxr guys, buell guys, It doesn't matter, what you ride as long as you ride.

Of course with the number of wrecks on some of these rides, I think that I may stop doing that.
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Snowscum
Posted on Saturday, September 22, 2007 - 12:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

He was saying the cupping is from out of balance condition of either the brake or wheel. I don't get any head shake that I can feel. I remember people talking about the cupping but didn't really pay much attention to it till mine started to. Could a soft front end also cause that? I mean when I hit the front brakes it dives scary bad. I just put up with it and stay back and anticipate. So far so good. Now would it be worth it to change out all the wheel bearing at that time? That is a question that I have been pondering as well.
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Snowscum
Posted on Saturday, September 22, 2007 - 01:08 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Yea the class envy is there. I was looking at the FZ when I was shopping. But its made for someone that is 6'. The Uly with the race kit was to hard to pass up. I don't really like riding with people due to my falling back. But I refuse to get killed keeping up. So I just put up with it when I do ride with people. I have never ridden with this friend. He rides to fast so there for I just don't ask. What really bothers me is when someone is behind me. It just is a total buzz kill for me. Just don't want to get plowed into.

Anyone know the wheel base on a GP bike?
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Mikef5000
Posted on Saturday, September 22, 2007 - 01:24 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Cupping from being out of balance???

That's doesn't make sense at all. Out of balance = vibration.

It's a dual sport tire, that you're running (spirited) on the street. It's going to cup a bit.

Put a set of snow tires on your car, and look at them after a few thousand miles on dry pavement.
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Akbuell
Posted on Saturday, September 22, 2007 - 03:55 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Quick comment #2. The OE Dunlop front on my X-1 was noticably cupped at about 7500mi when I replaced it. The Metzlers I have on now show no signs of cupping a 5000+ miles, and the bike handles better, especially on turn-in. And I pay careful attention to tire pressure. And your Uly dives more under braking because the front suspension is set up softer, for more travel/softer ride on unpaved surfaces.

Bottom line, if you like your bike, all else is water under the bridge. What others think
doesn't matter.
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Xb9er
Posted on Saturday, September 22, 2007 - 06:45 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

check your owners manual and set your suspension to your height/weight
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Jlnance
Posted on Saturday, September 22, 2007 - 07:35 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

About stability. In the context that's being used here, stability has a very specific meaning, which is different than what most people probably think it is. More is not necessarily better (but not enough is definitely bad.) Increasing the stability slows down the response of the bike to inputs, making it harder to turn. This is exactly why the XB has a short swingarm.

You friend is yanking your chain, because if he is an aeronautical engineer he knows this. High performance aircraft have an airframe that is unstable, and use a computer control system to make them flyable. By using an unstable airframe, they achieve much greater agility than would otherwise be possible.

http://www.flug-revue.rotor.com/FRheft/FRH9909/FR9 909e.htm
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Diablobrian
Posted on Saturday, September 22, 2007 - 10:06 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Aircraft like the B2 are reputed to be nearly un-flyable without the computers altering the surfaces via the servos.
That admittedly is taking the concept to the extreme, and not all air frames are built on this concept. In fact not
many are.


I don't have the books in front of me to show the math of this, but depending upon the weight of the bike, the amount
of torque, the diameter of the wheel, amount of traction available, the Cg of the bike and the wheelbase the ideal
swingarm length is calculated for the bike depending upon it's design intent. Anyone that sat in on Abe's first
tech seminar at this year's homecoming will recall how excited he was to share this with us. It was great!

The FZ1 is heavier than the Uly, has a higher center of gravity, and longer wheelbase. Even just based on those
factors it is easy to see how the 2 bikes would end up with different "ideal" swingarm lengths.

Stating that a longer swingarm is always better does not sound like the opinion of any informed engineer... no matter
the specific discipline. Engineers are all aware that designing any and all machines is a game of trade-offs.
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