Gen I vs Gen II Comparison

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mcatrophy said:
One last post, and I'll keep it short (for me).
Cannon ball/feather analogy shows the ratio of weight to inertia is constant. In braking, weight holds the tyre onto the road, inertia tries to keep the bike moving. Inertia is proportional to weight. More correctly, both weight and inertia depend on mass.

Friction force of tyre to road depends on weight. With the bike on the side stand, try pulling your front wheel round. Hard, no? Now put the bike on the centre stand, pull up on the front of the front wheel. Oh, lookee, it turns (rubbing a little black stuff onto the ground, and possibly a little BS onto your hand). So, the more weight, the more friction force available. Just enough to deal with the extra inertia of that extra weight.

Finally, at least in modern systems, ABS doesn't work by bike deceleration, nor by comparing front to back wheels. It works by looking at the individual wheel's deceleration.

OK, that's me done.
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Look, I'm not going to try to give a physics lesson here because I am really not qualified, BUT the ratio of weight to inertia???? Come on!!!!! Weight is a force. It is mass under the accelleration of gravity. Inertia is the tendency of a body at rest to remain at rest or a body in motion to remain in motion. The effect of gravity being a constant on two objects of different mass is because the force of gravity as computed by the universal gravitation constant times the mass of object one times the mass of object two divided by the distance squared and is swamped out by the mass of the earth compared to two objects in question and the comparitive distances are extremely short. Feathers only apply when in a vacuum and none of this has anything to do with brakes slowing down a motorcyle. In the grand scheme of things 16lbs of ABS is insignificant in the stopping distance, BUT overall weight IS significant. If anyone wants a demo, lets set up a time and date and meet in Franklin, NC to run NC 28. I'll be on my Sprint ST and you be on whatever year FJR you want. We have the exact same wheel and tire specs and the FJR has a 27hp theoretical advantage. The ST is around 150lbs lighter. Those 600's will probably smoke both of us but anyone who thinks you can stop a significantly heavier bike as fast as a light one you need to try it on the road rather than out of some report.

 
The originating seed for this thread was innocuous enough, but it seems to have taken a dark twist when growing up and has blossomed into a full fledged turd exercise in frustration and futility with a little :trinibob: added in.

At this point I think the thread is like a body that keeps on running long after it's dead. The information to noise ratio has gotten very, very small.

Somebody bring a shovel and headstone. :rip_1:

 
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Hm, I don't know that you can say a heavier bike always stops slower than a lighter one, effciency of design comes in to play there I think, as does weight ratio, suspension, too many things to list. I guess that's why we simply test the end result:p That aspect of the discussion doesn't matter much to me, without a doubt my FJR is the best braking bike I have ever owned. It's not the quickest, it's not the best handling although it's pretty close on those fronts as well. It's definitely the best all around bike I have ever owned. The only real performance complaint I have is it seems the motor loses a bit when the revs speed up. Maybe that's because my other bike is really weak at the low end and comes to like at about 8k.

Someone spoke of a seat complaint. Have you tried playing with your seat height and bar adjustments? When I first got my bike I road with the seat down and the bars all the way back. After having it about six months I switched to seat up bars all the way forward. Both my wife and I enjoy riding the bike much more in this configuration. My back is no longer sore when riding 2 up, she is much more comfortable overall and believe it or not the saddle works loads better for me in this configuration.

And Warchild still didn't mention what he thinks of his R1 as a second bike, bah....

 
sprint_st said:
Look, I'm not going to try to give a physics lesson here because I am really not qualified, BUT the ratio of weight to inertia???? Come on!!!!! Weight is a force. It is mass under the accelleration of gravity. Inertia is the tendency of a body at rest to remain at rest or a body in motion to remain in motion. The effect of gravity being a constant on two objects of different mass is because the force of gravity as computed by the universal gravitation constant times the mass of object one times the mass of object two divided by the distance squared and is swamped out by the mass of the earth compared to two objects in question and the comparitive distances are extremely short. Feathers only apply when in a vacuum and none of this has anything to do with brakes slowing down a motorcyle. In the grand scheme of things 16lbs of ABS is insignificant in the stopping distance, BUT overall weight IS significant. If anyone wants a demo, lets set up a time and date and meet in Franklin, NC to run NC 28. I'll be on my Sprint ST and you be on whatever year FJR you want. We have the exact same wheel and tire specs and the FJR has a 27hp theoretical advantage. The ST is around 150lbs lighter. Those 600's will probably smoke both of us but anyone who thinks you can stop a significantly heavier bike as fast as a light one you need to try it on the road rather than out of some report.
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What gives an object its weight? Its mass, acted upon by the mass of the Earth. What gives an object its inertia? Its mass.

16lbs or 160lbs, don't care. Weight is up by 160lbs, that's 160lbs more pressing the tyres onto the ground. More grip available. In direct proportion to the extra inertia.

Would love to come to Franklin, NC to run NC 28, but not practical, I'm on the other side of the Pond.

And, FWIW, I have an engineering degree. That doesn't necessarily mean "I'm right, you're wrong", but I do have a fair grounding in motion of bodies (inanimate only), even if I can't get the message across.

Nearly bought a Sprint ST, enjoyed the test ride, but forced to the clutch lever-less FJR by my arthritic little finger.

 
I am waiting on Jestal to chime in here... This should be a good one. :jerry:

After reading *some* of these posts, I am quite dumb by their extensive knowledge! :blink:

 
am waiting on Jestal to chime in here... This should be a good one
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I've sat this one out on the sidelines because ABS has already been (over) done in this thread here. Stop by and read what it has to say about ABS. Besides, you will get to meet some of the bright burning, short lived shooting stars of days past :lol:
 
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Ari Rankum said:
And two, it's SAMMICHES, dammit.
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I concur that on the Right Coast, it is indeed sammIches, but out here in La-La Land, the saline puff bags have demoted the "I" to a lesser status "A". Well, that and massive injections of Botox makes it a lot easier for starlets and has-beens to pronounce 'ah' v. 'eye'. Their lips usually pop and puss festers out when they try...

 
:yahoo: Beauty twn! and with that this post should die off. :dead:

But I doubt it.

I'm thinkin of fillin the brake lines on my bike with Yukon Jack, as the alcohol content should be sufficent enough to keep boiling a non issue. An if by chance I happen to brake down I'd have sumpin' ta drink :)

sound ok by use guys?

:jester:

 
I like Yukon Jack; I like the look of A.J.'s lips; I like NC 28; but, I don't like ABS.....

But, what I really want to ask about is:

What gives an object its weight? Its mass, acted upon by the mass of the Earth. What gives an object its inertia? Its mass. 16lbs or 160lbs, don't care. Weight is up by 160lbs, that's 160lbs more pressing the tyres onto the ground. More grip available. In direct proportion to the extra inertia.
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How come? I can skid either wheel (if I want) without adding or removing weight?But, I'm not gonna ask it -- and perpetuate this tu.. of a thread. :( :p

 

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