F6B To The Dark Side

[Mustangjake]

I would pull my hair out if I had any

[ghostrider]

Any connection to your screen name?

I'm a huge Peart/Rush fan. Have seen their shows several times -always great!

Yes, as a matter of fact it is. I'm a big fan too, really enjoyed reading his books and seeing RUSH in concert. I originally saw them at the swing auditorium in San Bernadino when they played backup to another band during their 2112 album concert. Just blew away the audience.

[ghostrider]

http://neilpeart.net/index2.html

This is the link to his web site if anyone is interested. (hoping it's a link)

[Teach]

Bob, sure I can, but it would be much better if I just quote a fella I know who knows more about DS conversions than anyone else.

"If the centerline of the wheel stays in the same place, then static loading on the final drive bearings remains the same, regardless of how you get there.
All that the bearings 'see' is how far away from me is the load applied (centerline) and how much (total mass being supported at that wheel).

If you offset the wheel farther away from the final drive, then the output shaft will see a larger moment load which will result in addition loading on the bearings.

Imagine a bar held horizontally in your hand, as a weight gets moved farther out away from your hand it has a greater torque load that your hand/wrist much resist in order to keep the bar from sagging.

-----

Now, imagine adding extra weight at the same spot on the bar you are holding, and you will agree that it also takes more work to hold the bar level, right?
That is analogous to what would happen if you go with a heavier wheel/tire.
OR..... if you add extra mass.

Except, our wheel assembly is not hanging out in space, it is resting on the ground and holding up the final drive (and rest of the bike/rig).
So when stopped the extra weight of the heavier wheel has no effect on the load seen by the final drive bearings.

BUT....
You didn't buy the bike/rig just to have it parked and looking pretty, so you drive down the road. And while driving down the road you will hit bumps, causing the suspension to move.
NOW that added wheel/tire mass does have some effect. The wheel/tire/final drive/swingarm is all mounted "below" the spring/shock unit and is refered to as the 'Unsprung Mass'.
Greater unsprung mass affects how quickly/well the suspension can react to being bumped. Basically, it takes more energy to both get it moving, and stop that movement when you have more mass.
Which means that with a heavier wheel/tire your suspension is going to feel harsher, and in some cases may not stay in contact with the road/trail as well.

And, there is then an inertial force that is transmitted to the bearings of the final drive as the wheel bounces around on the end of the output shaft. The larger the mass that the final drive bearings are trying to control, the more load the bearings see.
The heavier the wheel/adapter, the more force transmitted. And, the rougher the road/trail, the more inertial force transmitted through the output bearings due to larger/faster/more frequent movements of the unsprung mass.

Yes, inertial loading is probably a smaller component to the final drive bearing loads than static loading, but NOT insignificant."

Hope this helps.......

[bob109]

Bob, sure I can, but it would be much better if I just quote a fella I know who knows more about DS conversions than anyone else.

"If the centerline of the wheel stays in the same place, then static loading on the final drive bearings remains the same, regardless of how you get there.
All that the bearings 'see' is how far away from me is the load applied (centerline) and how much (total mass being supported at that wheel).

If you offset the wheel farther away from the final drive, then the output shaft will see a larger moment load which will result in addition loading on the bearings.

Imagine a bar held horizontally in your hand, as a weight gets moved farther out away from your hand it has a greater torque load that your hand/wrist much resist in order to keep the bar from sagging.

-----

Now, imagine adding extra weight at the same spot on the bar you are holding, and you will agree that it also takes more work to hold the bar level, right?
That is analogous to what would happen if you go with a heavier wheel/tire.
OR..... if you add extra mass.

Except, our wheel assembly is not hanging out in space, it is resting on the ground and holding up the final drive (and rest of the bike/rig).
So when stopped the extra weight of the heavier wheel has no effect on the load seen by the final drive bearings.

BUT....
You didn't buy the bike/rig just to have it parked and looking pretty, so you drive down the road. And while driving down the road you will hit bumps, causing the suspension to move.
NOW that added wheel/tire mass does have some effect. The wheel/tire/final drive/swingarm is all mounted "below" the spring/shock unit and is refered to as the 'Unsprung Mass'.
Greater unsprung mass affects how quickly/well the suspension can react to being bumped. Basically, it takes more energy to both get it moving, and stop that movement when you have more mass.
Which means that with a heavier wheel/tire your suspension is going to feel harsher, and in some cases may not stay in contact with the road/trail as well.

And, there is then an inertial force that is transmitted to the bearings of the final drive as the wheel bounces around on the end of the output shaft. The larger the mass that the final drive bearings are trying to control, the more load the bearings see.
The heavier the wheel/adapter, the more force transmitted. And, the rougher the road/trail, the more inertial force transmitted through the output bearings due to larger/faster/more frequent movements of the unsprung mass.

Yes, inertial loading is probably a smaller component to the final drive bearing loads than static loading, but NOT insignificant."

Hope this helps.......

I deeply appreciate your informed response Your time at the podium was well spent

Cordially

Bob

[Mustangjake]

The first law is easy to believe:*The friction between two surfaces is proportional to the force pressing one to the other.*This force could be the weight of a motorcycle pressing the tire into the pavement, or the clamping force pressing two pieces of wood together. "Proportional" just means that if you double the pressing force you double the friction.*The second law is where all the trouble starts. To understand it, suppose you set up an experiment. You put a brick on a table and investigate how much force it takes to start the brick sliding. You screw an eyebolt into the brick, run a line from the eyebolt to a pulley on the edge of the table, and then attach weights to the end of the line. You add weight until the brick starts to slide.Now here's the interesting part, and the surprising part. You would notice that the orientation of the brick doesn't make any difference. That is, the friction is the same whether the brick is on its large face, the smaller side, or the small end.

I never compared a brick to a tire!

[Steve 0080]

As far as the brick goes....You are measuring the drag coefficient of the table or surface the brick is on….drag coefficient means little in this discussion…other than the power needed to move the brick/tire or the stopping ability on the surface…

[Gumby]

The first law is easy to believe:*The friction between two surfaces is proportional to the force pressing one to the other.*This force could be the weight of a motorcycle pressing the tire into the pavement, or the clamping force pressing two pieces of wood together. "Proportional" just means that if you double the pressing force you double the friction.*The second law is where all the trouble starts. To understand it, suppose you set up an experiment. You put a brick on a table and investigate how much force it takes to start the brick sliding. You screw an eyebolt into the brick, run a line from the eyebolt to a pulley on the edge of the table, and then attach weights to the end of the line. You add weight until the brick starts to slide.Now here's the interesting part, and the surprising part. You would notice that the orientation of the brick doesn't make any difference. That is, the friction is the same whether the brick is on its large face, the smaller side, or the small end.

I never compared a brick to a tire!

If that was relevant in tires a dragster would have skinny tires for the least rolling resistance.

They, of course, do not.

We had a physics teacher that told his students otherwise using the brick example. his insistence that the bumblebee could not possibly fly despite observational proof turned dozens of kids off of physics. His successor showed where he was wrong. I forget how she did it.

The reason I don't welcome Teach's input is because there are hundreds of threads debating the merits of ct. I don't want to hear from any more people who have never and will never try it. 100,000s of thousands of miles have been very successfully been put on CTs. Probably millions of miles. The question I'd like to explore, and what this thread was about, is what kind of CT is the best for the F6B. The endless debate just detracts from that with no benefit.

[MichaelG]

The reason I don't welcome Teach's input is because there are hundreds of threads debating the merits of ct. I don't want to hear from any more people who have never and will never try it. 100,000s of thousands of miles have been very successfully been put on CTs. Probably millions of miles. The question I'd like to explore, and what this thread was about, is what kind of CT is the best for the F6B. The endless debate just detracts from that with no benefit.

Well said, Gumby...well said.

[Teach]

Gumby,

You see there in lies your problem, you did not read and you ASSUMED wrong. I posted right up front that I have in fact ridden with a Darkside setup, in fact I have THOUSANDS of miles riding on that setup. I still have a brand new Potenza sitting in my barn that didn't get used.
That mistake aside, you cannot make an INFORMED decision as to the merits and/or pitfalls of running a CT, without considering ALL the variables (hence my discourse with Bob). IMO there is a SIGNIFICANT down side to running a DS rig on a single sided swingarm, aka FD as opposed to a traditional 2 sided swingarm. Far more variables to consider in setup. There is also the hydroplaning argument which cannot be gotten around. There are SURELY benefits to running DS like more rubber on the road, longer tire life, less tippy when stationary.... but you cannot discount the negatives.
You can run whatever setup you want, your bike, your money and your life in the saddle. All I'm saying is be INFORMED. That means when someone tells you a CT won't hydroplane any more than a bike tire, know it for the BS it is. That doesn't mean don't run the CT, it means know it WILL hydroplane much easier than a bike tire so you don't put yourself in a BAD situation. It means know that an alum wheel will NOT in all instances be the best choice of wheel, factor in weight. Cool looks could get you dead or damage your bike badly. It means with a final drive like the GW has, being on center is very important as is the total weight of your setup, for safety and to prevent damage to the bike.
I am sorry you felt we were debating the merit of running a DS setup, rather than discussing things of importance, things that NEED to be considered when pondering a DS setup.

ps... I run a DS rig on my BMW when towing my trailer (FD, single sided swingarm) and I am as informed as one could get on the merits and pitfalls. Bet you didn't see that coming either