Hobot, you think you can ride a flexy flier?

Holmeslice

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Check out these XR1200s...

http://youtu.be/3JkSHRAsCfU

I watched these guys at Indy MotoGP this year. Some of the best racing of the weekend with their wide bars and flexible frames wobbling as they pulled it down into T1. The spec rules are strict and the bikes are being ridden harder than they were ever intended.
 
Holmeslice said:
Check out these XR1200s...

http://youtu.be/3JkSHRAsCfU

I watched these guys at Indy MotoGP this year. Some of the best racing of the weekend with their wide bars and flexible frames wobbling as they pulled it down into T1. The spec rules are strict and the bikes are being ridden harder than they were ever intended.

That's because they were only meant to turn left and slide the rear wheel...
 
Whew Kenny had me there with subject line, I was expecting to see video of the Indian braves bouncing along on compliant frames one hand on the long horn bars and other on long shift handle like a coin operated ride outside grocery stores.
Instead you show modern rigid balloon tired rig I expect to go nuts on the poor pilots, they are too unpredictable for me anymore. I couldn't see what started it but know its a very bad visual sensation more than emotion you mostly just go down with. Then the emotions hit to understand and find correct what went wrong. More so if nothing learned > must face it again or quit. All the bikes i've creeped up on eventually did that death dance going into or out of some mild lean at speed, but one.

Hm going by what THE Gravel teaches there's an automatic transition of counter to straight steering and back when a bike is kinda neutral condition where it don't take forks to help it lean this way or that or steer, even in a turn if point hit where bike can hold its own angle and radius the forks can jerk back to point the way the bike is naturally falling towards. But we've talking silly mm or two differences to start off. I think its this oscillation and tire conflict that needs absorbing to be safe for my fun and those floppy ear'd Indains that just hook it on around with forks going back and forth but frame flex allowing it. I get a bit sea sick flashing back on them.

You know the feeling of self steering Commando, that's why you get surprise peg pogo's too, because there's still grip to go lower harsher and no kick back till prong!
 
I think what happened is as he came out of the corner he thought he was on the straight and relaxed for a moment . :shock:

Gives the symptoms of being underdamped at the rear , or is that tyre elasticity or slip grip slip grip .Never shut the throttle Off in a
Drift

Nice acrobatics too , he looked like he was still trying to drive it while he was airbourne . 10 points for initiative . :|
 
It looks like fun till the first hand lets go, then you wish you were 300 feet back and re-think the corner exit again...
 
hobot said:
...
Instead you show modern rigid balloon tired rig I expect to go nuts on the poor pilots, they are too unpredictable for me anymore....
Ummm....aren't XR1200s rubber mounted almost exactly like your tri-link Peel :D

Just sayin'...
 
willh said:
Ummm....aren't XR1200s rubber mounted almost exactly like your tri-link Peel

Nope, they don't have the swingarm attached to the engine like Commandos do.
 
grandpaul said:
[quote="willh]Ummm....aren't XR1200s rubber mounted almost exactly like your tri-link Peel

Nope, they don't have the swingarm attached to the engine like Commandos do.[/quote][/quote][/quote][/quote]
Are you sure :?:
http://i39.tinypic.com/x1yip4.jpg
looks like the swingarm shaft is solid in the case and rubber in the frame doing double duty as rear engine mount.
 
Whoa! Stop and hit this before preceding into my special infection mood.
You know what name I hear in place of the purified agreclutural white powder.
[video]http://www.youtube.com/watch?v=dRCkWsoJzZo&feature=player_embedded[/video]


The only thing Peel's not meet for a test of pecking order is a well ridden XR750 or a Buell. Of all the two wheeled variety that is the pair that tingles my spine the most to out handle and power response. Ole Hopper tired to correct Harley but they insisted on diaphragm rubber that a single rod link can't keep in one plane. At least they got some with 3 rod links I"ve had detailed to N'th degree by the hi end Harley shops here. Btw by far the best handling bike that most gives me the creeps was a low 40's HD with inline 3rd wheel trailer. He is the 2rd person I've know of doing drifts hands off grinning.

This is the terror-tory THE Gravel puts me in routinely. I watched the video again to see the first thing to hit was a flick in the forks a few bikes lengths after he began to lift back up past the painted berm. His bike fought him to stand back up, so he subtracted counter steer = more towards straight steer to help lift it, but that suddenly put too much traction on front compared to rear so with a ringing Non Complaint Chassis it could not absorb it but feed it back into rear to let go far enough out to trip the hi side Fang Dang Go.

Pushing V Twin vs inline 4 to my meager limits, implies the v twins tend to fall into turns but fight the lift ups, while the inline4's fight the throw down by wanting to fly up. Believe it or don't but I forced myself as well as fates to learn to out ride even these limits on a v twin and inline 4 but it can't be done staying in phase 2 two tire contract counter steer and these moderns are too brittle a chassis frequency to take the spike of energy that snaps though them the instant you force just one tire to break free, as video demo'd.

Can't blame pilot error, it was not that bad a turn and he fought the fight which hurts with spikes of adrenaline to keep on it and not bail But as I learned if that ain't your first reflex or decision then find another hobby.

I know Ms Peel could get that sideways with tank slap at 50+ and let me save her, BUT NOT WITH THE FACTORY FORK RANGE, No Sir Ree BoB, to counter that kind of frame wind up and release needs a hand full more degrees of freedom. I made the space on the fly up before the landing, then rode home 6 miles. There are two miracles here that calm me soul to tease with the Big V Dogs, 1st - rump rod + 2 helpers, 2nd - non seeing any straight steer but on crash video. A rear tire de rimmed on Peel over a crest to onset upset not a loss of control, duh.

The sad facts of the matter is designers know they need some compliance but for the life of em can't figure out where or how to provide for it yet stable to take up tire and CoG conflicts. The sad facts of the matter is that even if you lift one tire, say the front out of frame influence by powering up a crest, like they do in the TT-IOM, you'll see they do essentially the same thing all the way to the forks, so thank goodness they were going straight and forks not touching till acceleration eased and front came down.

Its takes hi siding both tires up to get the moderns shakes out but then so wigglely and balloon tire greasy springy, they fast become un predicable form all the splashes combining with the wind eddies, so can't spike it all at once to leap each and every time excatly for the impacting it all at once on landing it perfect to nail it right out of there. If you ain't going in fast enough to crash any way then can't practice phase 4 fun. There is only one tool of choice for me now.

What is the definition of a truly Neutral handling motorcycle?
What would it do differently? How would you know?
What would pilot feel about it? What would pilot do with that feeling?
Is a steering damper even possible in a truly nuetral handling motorcycle?

If ya want to hang out, ya got to take Her Out ---->
When ya want to get down, Down On THE Ground --->
She's Alright, She's Alright --->
When the days is done and ya Wanta Run --->
 
Harley's are Norton's closest kissing cousins is many ways both in designers and shared issues.

The TC88 motor that is used in the Dyna and touring models is rubber mounted, which means that there is no metal-to-metal contact where the engine mounts to the frame. The TC88B engine used in the Softails (since '99, I think) is a balanced engine, which has two chain-driven counterbalancers located inside the cases that greatly reduce the vibration from the engine.

The rubber mounted TC88 engines will vibrate much more than the solid mounted TC88B balanced engine. I know that sounds hard to believe, but it's true. HD engineers had to change the transmission back in '99 because the vibration from the old motor would aid in shifting gears, and the reduced vibration of the TC88B made the shifter feel stiff and awkward.
/

cycleso's answer is correct... the TC/B will sit on it's kickstand at idle with out any movement in the rear view mirrors (take that Harley basher)... the rubber mount will look like it wants to walk out of the room... HOWEVER at speed the rubber mount is very smooth also. The first time I saw a B motor idle I thought the rubber mounts would be obsolete... they are not, but I think it's more of a problem with HD changing all the frames over on the rubber mount bikes. The B motor is very very smooth even though it's on solid mounts. Just as an aside... you also don't have to deal with exhausts that need to be able to vibrate with the motor when you ride a solid mount B (counter balanced) motor.
 
Hi

This series runs with the British Superbike series in the UK.
When Lee was riding the bike he said it was like the saying it has a hinge in the middle :D only the Harley had two hinges :D :D :D
Gearbox is ? not?

Chris
 
Kissing cousins we are I tell ya, maybe even ahead of us with tri-linked offerings

Hobot, you think you can ride a flexy flier?


Hobot, you think you can ride a flexy flier?


Hobot, you think you can ride a flexy flier?


Hobot, you think you can ride a flexy flier?


Hobot, you think you can ride a flexy flier?


Hobot, you think you can ride a flexy flier?
 
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