slightly larger spare tire & rear locker (6 Viewers)
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plus geologists really do lick rocks and chew mud...it's not a figure of speach!
Do you really lick your laptop?
swamp60
Do you really lick your laptop?
swamp60
Well as can be seen we Cruiserheads come from all walks of life... I'm a Chef by day and just wish i didn't have to work so many weekends.... need more time to wheel... 
rusty_tlc
Dain Bramaged Member
They don't close the trails during the week.Well as can be seen we Cruiserheads come from all walks of life... I'm a Chef by day and just wish i didn't have to work so many weekends.... need more time to wheel...
Mark W
Yep, I really don't really care that much I guess.
Don't any of you guys arguing this drive a rig with an autolocker?????
Air a tire down and you will feel the difference as the changed rolling radius affects the locker. It does not take much.
You'd spend less time testing this yourself than you have spent arguing.
Also... Something that some may be forgetting or misunderstanding... a point on the out edge of a tire does NOT move at a constant speed. It is NOT like the tread of a tank. Lower the air prerssure, let the tire sag more, decrease the distance between the tread in contact with the ground and the center of the rim and the sped of the tread as it passes though that area of rotation is decreased. As that portion of the tread rotates away from the ground and is unloaded, it is allowed to move further away from the center of the wheel and the speed at the tread surfaces increases. It is NOT a rigid circle that is rotating and the movement of any point on the tread as the tire rolls is NOT circle and NOT a constant speed.
Mark...
Mark...
Air a tire down and you will feel the difference as the changed rolling radius affects the locker. It does not take much.
You'd spend less time testing this yourself than you have spent arguing.
Also... Something that some may be forgetting or misunderstanding... a point on the out edge of a tire does NOT move at a constant speed. It is NOT like the tread of a tank. Lower the air prerssure, let the tire sag more, decrease the distance between the tread in contact with the ground and the center of the rim and the sped of the tread as it passes though that area of rotation is decreased. As that portion of the tread rotates away from the ground and is unloaded, it is allowed to move further away from the center of the wheel and the speed at the tread surfaces increases. It is NOT a rigid circle that is rotating and the movement of any point on the tread as the tire rolls is NOT circle and NOT a constant speed.
Mark...
Mark...
When I drove a BJ60 with autolockers I knew when I had two tires in the back which had mismatched tire pressures. The locker was not happy. Put them both to the same PSI, and it was happy again.
When I had one (aussie locker) I bought my tires in sets of 5, and made sure the spare was in the rotation.
gb
When I had one (aussie locker) I bought my tires in sets of 5, and made sure the spare was in the rotation.
gb
I believe you. But I think that it's caused by the difference in resistance of the tires, rather than difference in "effective diameter"
MarkMark, it took me a while before I knew what was wrong with your story, but know I know
. When you decrease the distance between the center of the rim and the piece of tread that touches the ground (let's for now use the division of 72 pieces x 5 degrees from my earlier example), the speed of that pieece of tread increases, instead of decreases. Because in the same amount of time, the same amount of tread must pass through the piece of pie of five degrees. It is still five degrees, but because it is closer to the center, de distance between the two "legs" of the five degrees is shorter.But the tread can't go faster, compared to the street, otherwise your car (sorry, Cruiser) would make a turn instead of going straight ahead. So your diff will start to work to compensate that, or your Aussie or Lockrite locker will disengage, if you have one.
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Completly backwards.
The "speed is maintained by the motor, not the edge of the tire.
When you decrease the effective radius (and the "effective circumfrence") you decrease the speed of the vehicle at a given RPM.
That is why larger tires cause your speedo to read slow..
Indeed, Macepersoncreature! The speed of the motor (if you would stay in the same gear and don't alter the RPM's of the motor, and drive in a straight line, and if you would have a locked differential) and the amount of tire surfice/tread that goes around/move along the ground in one cycle, is a constant factor. And it doesn't change as long as you don't put another tire under your rig
This answer is correct.
The question here is the tangential velocity of each tire which is the angular velocity times the radius at the point where you measure it. Rubber deforms so the constant arc length (i.e. circumference) of the unloaded tire hypothesis doesn't apply here.
This is why unequal effective radii due to unequal tire pressure or mismatched tire sizes screw with auto lockers.
It has nothing to do with rolling resistance in this case because the tires are not slipping. If unequal resistance means one slips and the other doesn't, that is a different story.
I am an ME.
Frank
Mark W
Yep, I really don't really care that much I guess.
Meth..... No offense meant... but you really need to sit down and talk with someone face to face who can explain this and maybe show you with pencil and paper and some basic geometry. Seriously... Maybe a High School math teacher. It will seem glaringly obvious once you get the first grasp of it.Mace and I really do know what we are talking about, both from a real world user and professional builder point of view and from the designer/engineer take as well.
EDIT: And Frank too!
Trust us.... You really do not have as firm a grasp on this as you think. Flat ass backwards on a couple of points here.
Your argument defies the laws of physics on at least one major point.... smaller radius yields greater speed at the tread? Really????
Have you used a rig with a locked rear axle very much?
Mark...
EDIT: And Frank too!
Trust us.... You really do not have as firm a grasp on this as you think. Flat ass backwards on a couple of points here.
Your argument defies the laws of physics on at least one major point.... smaller radius yields greater speed at the tread? Really????
Have you used a rig with a locked rear axle very much?
Mark...
MarkMark, it took me a while before I knew what was wrong with your story, but know I know
But the tread can't go faster, compared to the street, otherwise your car (sorry, Cruiser) would make a turn instead of going straight ahead. So your diff will start to work to compensate that, or your Aussie or Lockrite locker will disengage, if you have one.
This answer is correct.
The question here is the tangential velocity of each tire which is the angular velocity times the radius at the point where you measure it. Rubber deforms so the constant arc length (i.e. circumference) of the unloaded tire hypothesis doesn't apply here.
This is why unequal effective radii due to unequal tire pressure or mismatched tire sizes screw with auto lockers.
It has nothing to do with rolling resistance in this case because the tires are not slipping. If unequal resistance means one slips and the other doesn't, that is a different story.
I am an ME.
Frank
Meth..... No offense meant... but you really need to sit down and talk with someone face to face who can explain this and maybe show you with pencil and paper and some basic geometry. Seriously... Maybe a High School math teacher. It will seem glaringly obvious once you get the first grasp of it.Mace and I really do know what we are talking about, both from a real world user and professional builder point of view and from the designer/engineer take as well.
EDIT: And Frank too!
Trust us.... You really do not have as firm a grasp on this as you think. Flat ass backwards on a couple of points here.
Your argument defies the laws of physics on at least one major point.... smaller radius yields greater speed at the tread? Really????
Have you used a rig with a locked rear axle very much?
Mark...
anybody got some asprin ? my heads hurts again...
I can definetly tell when one of my back tires are lower than the other... i check my psi about every other time the 60 comes out of the garage.... I think every tire probabaly acts a little different... I know my Q78 Buckshots act a whole lot different than the bfg radials i had for street tires years ago...
Mark, you're right with the decreasing of speed in the smaller arc of the deflated tire. I mean, that would be the case maths wise, if you would forget for a while that although the "effective diameter" of the tire is smaller, you still have as much tread as when it was inflated. (wish I could do this in Dutch
). And that "deforming of the rubber" is just an easy way out, Frank. It's like stating that part of the tread goes through a space bending or a black hole. What I meant, is that although it's still five degrees, that part of the tread in the five degrees while inflated, has to travel though the smaller arc of the five degrees while deflated. So although at the deflated point the speed is lower, the tread has to speed up to catch up with the rotation speed of the rim/axle, that is still the same. And that is not possible if it doesn't slip on the rim.
). And that "deforming of the rubber" is just an easy way out, Frank. It's like stating that part of the tread goes through a space bending or a black hole. What I meant, is that although it's still five degrees, that part of the tread in the five degrees while inflated, has to travel though the smaller arc of the five degrees while deflated. So although at the deflated point the speed is lower, the tread has to speed up to catch up with the rotation speed of the rim/axle, that is still the same. And that is not possible if it doesn't slip on the rim.
I think it would be more common sence not to use different tire sizes, your asking one tire to rotate as a slightly different speed then the other. I can imagine that would 100% strain on the entire drive train...especially the differential gear teeth at the same time.
Mark W
Yep, I really don't really care that much I guess.
You are confusing degrees of rotation with linear distance (measured a the circumference).
5 degrees at 1 foot from the center point is much less than 5 degrees at 10 feet from the center.
Your diagram clearly shows the difference if you shift your mindset a bit.
Rubber DOES stretch and deform... and so far as the point at the tread is concerned it DOES speed up and slow down.
Mark...
5 degrees at 1 foot from the center point is much less than 5 degrees at 10 feet from the center.
Your diagram clearly shows the difference if you shift your mindset a bit.
Rubber DOES stretch and deform... and so far as the point at the tread is concerned it DOES speed up and slow down.
Mark...
Dear Mark, that is exactly the point at which I think that you forget something. Math wise you're right. If you decrease the circle, the arc gets smaller. But because the amount of tread in the real world stays the same (I don't swallow the idea of shrinking rubber - not that much
), it's a total different story.
