Another scenario

Tached1300

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Ok I feel like my other post missed the mark I should have left chicken strips out of it to perhaps elicit a better response.

Here’s the new scenario at a track day, will an instructor riding a passenger/Student around the track have to lean the bike as far as he would w/o passenger while carrying the same speeds???

If the instructor weighs 195 and his passenger weighs 245lbs they weigh combined close to the weight of the bike or as much depending upon the bike. Does there combined weight make the bike want to run ride and thus it takes even more effort to turn? Or given that their weight is on the inside of the bike it allows the bike an easier time making the bend as in less angle required?

Thanks for any thoughts on this, my favorite saying is “seek first to understand”
 
Number 1 . . .
NEVER ride with a passenger heavier than yourself...

Number 2 . . .
Only ride with passengers in extreme emergencies.

Number 3 . . .
I’ve never seen anyone ata track day riding with a passenger :rolleyes:
 
This is a physics question, absolutely not my area of training, but I'll play.
I'd imagine that the force required to cause the necessary lean angle would be greater, and the added weight would try and straighten the bike's trajectory so more lean angle would be required to counteract that. I may be completely wrong, but it makes sense in my head.
There are some engineering types around here, maybe they'll chime in.
 
This is a physics question, absolutely not my area of training, but I'll play.
I'd imagine that the force required to cause the necessary lean angle would be greater, and the added weight would try and straighten the bike's trajectory so more lean angle would be required to counteract that. I may be completely wrong, but it makes sense in my head.
There are some engineering types around here, maybe they'll chime in.
Thanks, I’m no physics guy either and I’m seriously just trying to understand I can see it possibly being either way but don’t know abd hoped those guys may chime in. Thought it would make a decent discussion
 
[QUOTE="Kiwi Rider, post: 3306816, member: 4712

Number 3 . . .
I’ve never seen anyone ata track day riding with a passenger :rolleyes:
[/QUOTE]

Wouldnt mind being a passenger on one of those Ducati GP bikes they run at MotoGP rounds...
 
You know we hang off the bike to reduce lean angle, not increase it right?
Ok I feel like my other post missed the mark I should have left chicken strips out of it to perhaps elicit a better response.

Here’s the new scenario at a track day, will an instructor riding a passenger/Student around the track have to lean the bike as far as he would w/o passenger while carrying the same speeds???

If the instructor weighs 195 and his passenger weighs 245lbs they weigh combined close to the weight of the bike or as much depending upon the bike. Does there combined weight make the bike want to run ride and thus it takes even more effort to turn? Or given that their weight is on the inside of the bike it allows the bike an easier time making the bend as in less angle required?

Thanks for any thoughts on this, my favorite saying is “seek first to understand”
First of all hanging off the bike is intended to reduce the lean of the bike. Overall weight makes turning the bike harder because all that mass wants to continue going straight. It uses up traction to resist this force and turn the weight. That's one reason a lighter sport bike can turn under you. That's also why @ROADTOAD1340 & @c10 are spending so much on Titanium.

The relationship between turning and leaning is a function of speed. So a given lean at a certain speed gives you a certain radius. Hold the same lean and speed up and the bike goes wide, slow down and the radius closes. Hanging off the bike changes the lean relationship by moving the CF of the mass (bike rider passenger) so that the radius to lean relationship is changed.

They do two ups all the time at track day Kiwi.
 
You know we hang off the bike to reduce lean angle, not increase it right?

First of all hanging off the bike is intended to reduce the lean of the bike. Overall weight makes turning the bike harder because all that mass wants to continue going straight. It uses up traction to resist this force and turn the weight. That's one reason a lighter sport bike can turn under you. That's also why @ROADTOAD1340 & @c10 are spending so much on Titanium.

The relationship between turning and leaning is a function of speed. So a given lean at a certain speed gives you a certain radius. Hold the same lean and speed up and the bike goes wide, slow down and the radius closes. Hanging off the bike changes the lean relationship by moving the CF of the mass (bike rider passenger) so that the radius to lean relationship is changed.

They do two ups all the time at track day Kiwi.
Makes sense to me..I watched a few of those videos and they basically said the same thing...

I haven't rode with a passenger on the bike in around 28 yrs..my wife used to ride with me back in the day...
 
You know we hang off the bike to reduce lean angle, not increase it right?

First of all hanging off the bike is intended to reduce the lean of the bike. Overall weight makes turning the bike harder because all that mass wants to continue going straight. It uses up traction to resist this force and turn the weight. That's one reason a lighter sport bike can turn under you. That's also why @ROADTOAD1340 & @c10 are spending so much on Titanium.

The relationship between turning and leaning is a function of speed. So a given lean at a certain speed gives you a certain radius. Hold the same lean and speed up and the bike goes wide, slow down and the radius closes. Hanging off the bike changes the lean relationship by moving the CF of the mass (bike rider passenger) so that the radius to lean relationship is changed.

They do two ups all the time at track day Kiwi.

Thanks for that response and yes I understand those basics and I was thinking given the fact that you have more weight from the Rider and passenger INSIDE of the curve that it would help with the bike wanting to run wide as it would be a counterweight of sorts but the passenger would be more neutral or at least not hanging off like the operator of the bike so I hadn’t taken that into the equation.

I’m not arguing at all I just thought there is enough weight in that scenario to rival the bike but that doesn’t taken the acceleration forces into account so I can see how the bike would still want to push forward and not turn.

Throttle control, using throttle to control cornering arc and increase or decrease radius etc I get all that and use it in my own riding.
 
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