Tire pressure

[CatatonicBug]

I change out my air with each climate change. I want to make sure I have matching air both inside and outside the tire.

My dad used to race go-carts professionally before I was born. He told me of one fellow racer who swore by the idea that he had to change the air in his tires after every race... No amount of logic could convince the guy otherwise.

[cywelchjr]

Seems to me I remember some minor incident involving Ford and Bridgestone. Apparently, Ford was recommending too low a pressure in the tire, because of ride quality.

OEM specs are arrived at for reasons other than performance.

That's correct. The tire manufacturer actually does have charts based on load and such for recommended tire pressure that are supposed to be used by manufacturers. As I recall, Ford actually lowered the recommended pressure in an attempt to lower the likelyhood of a rollover, thereby increasing the likelyhood of a blowout which would cause a rollover. It's one of those situation where they attempted to make something not happen and actually made it worse.

[Montreux_Blue]

40PSI on the front? Are you nuts? Be like riding on ice.

My bike stops and handles great in the rain, even well over the posted turn speed signs with no sliding or wheel hop. And like I said earlier....

Not a misconception but a trial and error evaluation over the time I have had the bike that works for me, obviously it may not work for everyone.

I had the bike in the low 30 PSI range when I got it and no air in the forks and after thousands of miles at different pressures, this is what works for me. It was actually very scary when it was soft. Plus I only weigh 145 lbs and the bike has roughly about 10 to 15 lbs of pieces removed from it.

[cywelchjr]

My bike stops and handles great in the rain, even well over the posted turn speed signs with no sliding or wheel hop. And like I said earlier.... I had the bike in the low 30 PSI range when I got it and no air in the forks and after thousands of miles at different pressures, this is what works for me. It was actually very scary when it was soft. Plus I only weigh 145 lbs and the bike has roughly about 10 to 15 lbs of pieces removed from it.

I'll have to admit, right now I'm running 38 front and 40 rear, and the ride seems to be good and solid. I tried lower and it actually started feeling greasy. Now then again, I am not a little guy , and my bike is a full dresser, so I figure I top a grand on the road.

[Crazcnuk]

"We get in some twisties... you won't have a choice. "

So you say. I put my money on you being the first one to slip off the side of the road.

"but if there were a perfect setup, then every professional rider/driver would be able to use the same setup.. correct?"

They do. You will find that given equal vehicles, tires, etc, the difference will be minor.

None of this is guess work.

"Anything less in the front shocks and I will bottom out too often"

Reread my post. I believe I mentioned that you shouldn't be bottoming out. However, you want to have as much available travel, too. Finding out where that 'sweet spot' is does take some trail and error, but many riders tend to have everything on the 'too stiff' side, thinking that is how it is supposed to be. Neither too soft, nor too hard is good.

When I can corner hard enough to get my pegs folded up and scraping screws "on the heat shield on the exhaust, then get hard into the brakes enough that the back tire comes off the ground a bit with the gears chattering as it skips along... I'd say there's still plenty of contact patch meeting the ground. Does that sound like someone riding on ice to you? "

If the next guy can corner even faster, then yes. Just because you have found the limits of YOUR nerves, doesn't mean you are anywhere near the true limits of the bike. The XS is not made to corner like a crotch rocket, so chances are you are being saved by the bike hitting the ground, rather than by your tires. The lean actually limits how hard you can corner.

To test this take a GSXR, CBR or other true sportbike and pump the tires 12psi over the recommended pressure and see what happens.

We would have to find out the max cornering Gs ever done on an XS11, then find out what you can do. Then we would know if you have the ideal setup.

You have to take into consideration many things. Road conditions, vehicle weight, sustained speeds, etc. Running too low a pressure increases tire heat, and reduces tire life. Too high elongates the tire (high in the center) reducing surface contact.

To illustrate, when we experimented to find the perfect pressure for my drag slicks, we started at 16psi. When I did a burn out, there was a 5" wide black mark left by the center of the tire, and two very thin lines at the outside edges "11.5" wide tires).

At <12psi two wide black strips at the outer edges and nothing in the center. Also would spin the rim inside the tire and rip the tube stem off.

At ~14psi Most of the tire contacts the road except for a 3/4" white line 2" in from each side.

That is a range of 4psi, or 25% top to bottom.

Like, I said I ran my suspension way hard for many years.

[Bigfoot]

If the next guy can corner even faster, then yes. Just because you have found the limits of YOUR nerves, doesn't mean you are anywhere near the true limits of the bike. The XS is not made to corner like a crotch rocket, so chances are you are being saved by the bike hitting the ground, rather than by your tires. The lean actually limits how hard you can corner.

Having ridden with Tod many times, if there is any of us that have found the true limit on his bike, it is him.

[trbig]

Reread my post. I believe I mentioned that you shouldn't be bottoming out.

Yup.. shouldn't be.. but even with 20psi in them I have ruined a fender. Stoppies and hard cornering will do that sometimes... and occasional hard landing from a wheelie. I guess maybe you're saying I should be putting in MORE than 20?

Just because you have found the limits of YOUR nerves, doesn't mean you are anywhere near the true limits of the bike.

That is probably my biggest problem, is that I don't seem to have a limit on my nerves, and why I won't get a more modern bike. If I had one that would do 200.. I'd try to go 205.

The XS is not made to corner like a crotch rocket, so chances are you are being saved by the bike hitting the ground, rather than by your tires.

LOL.. You have never seen me ride and are absolutely talking out of your azz.. The bike isn't hitting the ground.. I'm scraping screw heads. If the pegs are folded up and you're beginning to touch stuff that isn't meant to be touched.. you are at the limits of your machine and lean angle.. not nerves. If you were to ever actually hit, you'd take the weight off your tires and you're a goner. I have ridden with crotch rockets and have chased many many down in the curves. If you'd get over YOUR nerves, you'd see that they can corner very well.

Your whole post leads me to believe that though you may have a grasp on going straight, you haven't the slightest idea on twisties and actual road riding. I have lots and lots of witnesses that can attest to the setup I have, along with more miles in the seat per year than most. I've ripped through 40 and 45 mph curves at over 120 riding with a 1400 Concourse on different occasions with a guy who has quite a bit of track time under his helmet. He leaves me in the straights, but I catch him in the curves. That shouldn't happen.. and can't with a softer setup.

Look.. set your bike up like a Lincoln Continental spongy land yacht if you want. In the real world.. you're going to be flexing your sidewall too much, roll it over the edge, and actually have less a contact patch than I will in the corners.

I can sit and tell you of the thousands and thousands of hard riding twisties where I am actually way past the bike's design for cornering. I can tell you that less pressure in the tires and shocks makes me break traction sooner. I can tell you that I have experienced pushing machine and tires to their limits.. and beyond.. to the point that smoke is whisping off the tire and the bike is starting to drift a bit. I can tell you I know that this happens sooner with less air pressure because I've been there and done it. I can tell you I have first hand knowledge with thousands and thousands of miles of hard riding to back up what I say. You're just the kind of guy that gets it set intheir head and no amount of proof can change your mind.

So... not saying I won't ever slide off the road.. kinda surprised I haven't yet. But I believe I'll stay with a proven working setup, over your proven failed setup. May not work for all.. but it does for me and enough of them on here that I find it pretty dang humerous that you come on here trying to preach the opposite without listening to what most of the people have found out through trial and error. Quit reading a book and go ride a bunch of roads and find out yourself.If you find a softer setup for you works... great. You trying to tell me my (And many others') setup is wrong... lol. Now THAT is funny.. I don't care who you are..


Tod

[Crazcnuk]

"I guess maybe you're saying I should be putting in MORE than 20"

No, you shouldn't be riding like your 10.

"is that I don't seem to have a limit on my nerves"

If this were true, you'd be dead. I've known a few of those.

"LOL.. You have never seen me ride and are absolutely talking out of your azz"

As are you. Since you have never seen ME ride either.

"If the pegs are folded up and you're beginning to touch stuff that isn't meant to be touched.. you are at the limits of your machine and lean angle.. not nerves. "

Thank you for making MY point.

"If you were to ever actually hit, you'd take the weight off your tires and you're a goner'

Done it, still here.

"I have ridden with crotch rockets and have chased many many down in the curves. If you'd get over YOUR nerves, you'd see that they can corner very well"

Talking out your azz again? You have obviously chased down some amateurs on crotch rockets. You and I both know they will eat you alive, if they know what they are doing.

"Your whole post leads me to believe that though you may have a grasp on going straight, you haven't the slightest idea on twisties and actual road riding. "

Funny, I was thinking the same thing about you.


"I have lots and lots of witnesses that can attest to the setup I have, along with more miles in the seat per year than most."

More than me?

"I've ripped through 40 and 45 mph curves at over 120 riding with a 1400 oncourse on different occasions with a guy who has quite a bit of track time under his helmet. He leaves me in the straights, but I catch him in the curves."

So he isn't good in the corners, or your not telling us what he was riding.

"That shouldn't happen.. and can't with a softer setup."

It has nothing to do with 'softer'. It has to do with 'right'. Your setup may be perfect, no one said it wasn't. Actually, this was about TIRE pressures. The suspension was mentioned in passing for those that have less experience.

"Look.. set your bike up like a Lincoln Continental spongy land yacht if you want. In the real world.. you're going to be flexing your sidewall too much, roll it over the edge, and actually have less a contact patch than I will in the corners."

Just a little defensive are we? Can't have it rock hard so the only other choice is dead soft? You really have to learn to READ. No one said anything about being soft, only that a lot of people are set up too hard. However, if all you understand is all or nothing, not much we can do.

"I can sit and tell you of the thousands and thousands of hard riding twisties where I am actually way past the bike's design for cornering. I can tell you that less pressure in the tires and shocks makes me break traction sooner."

Of course, and tens of thousands of riders with millions of miles at speeds well in excess of what your XS weill do know nothing.

"to the point that smoke is whisping off the tire and the bike is starting to drift a bit"

But they aren't slipping....lol

"I can tell you I have first hand knowledge with thousands and thousands of miles of hard riding to back up what I say. "

But you can override my tens of thousands of miles?

"You're just the kind of guy that gets it set intheir head and no amount of proof can change your mind. "

"May not work for all.. but it does for me and enough of them on here that I find it pretty dang humerous that you come on here trying to preach the opposite without listening to what most of the people have found out through trial and error."

I beleive this is your problem not mine. Your the one not listening. No one said anything about your specific setup, but man you sure are unsure of it. Your the one talking the opposite of an entire industry that's been around for well over a hundred years. Your talking to people who have very little experience and are telling them to overpressure their entire system.

"Quit reading a book"

Can't read?

"and go ride a bunch of roads and find out yourself.'

I've been riding, steady, for 35+ years. In every kind of weather from sun to snow. Every month of the year where I had to boost my bike in the morning to get it run. I've ridden everything from dirt bikes to SECAs, Maxims to Shadows, XSs, CBs, GSXs, A100, etc, etc. I've had bikes that I put 100,000kms on.

I've build race cars, have an NHRA licence, have raced dune buggies on and off road. Spent countless hours working on suspension, frames, tires, drivetrains, balance, traction, handling etc.

If you find a softer setup for "you works... great. You trying to tell me my (And many others') setup is wrong... lol. Now THAT is funny.. I don't care who you are..

Your the only one telling anyone they are wrong, *******. Learn to read, be less defensive and discuss. "

And you aren't?

"So... not saying I won't ever slide off the road.. kinda surprised I haven't yet. But I believe I'll stay with a proven working setup, over your proven failed setup."

More azz talking? How has my setup failed?

[trbig]

Your the only one telling anyone they are wrong, *******. Learn to read, be less defensive and discuss.

LOL.. You kinda made my point. YOU are the one coming on here telling the majority of folks they are wrong, not listening to people who have been there and done that. So I guess that makes you an ******* right along with me. Running tires at their max and shocks UNDER their max isn't "overpressuring the system".

"to the point that smoke is whisping off the tire and the bike is starting to drift a bit"

But they aren't slipping....lol

They are.. and you like to ignore what people say to try to prove a point. They were slipping.. at a much higher speed than lower pressured tires.

More azz talking? How has my setup failed?

I've tried what you suggest, and that setup doesn't work as well for my bike or riding style.. so I would call that a fail. It's great for straight line riding, but isn't the optimal setup for ME or the majority of others that posted. You miss the poin tthat we all have made... that we've tried the recommended air pressures and found they didn't work. ACTUALLY tested it and found it doesn't work as well... but then you come tell us we're wrong. That's still funny.

No, you shouldn't be riding like your 10.

... lol. Which you should understand since many of the comments you make seem to be right in that area. Tell you what.. I'll quit riding like I'm 10 when you quit posting like you are.


Tod

[DGXSER]

No I am not a moderator however, can we please get back to discussing the subject and not slip further down the slope of going after each other.

Thanks

[Crazcnuk]

"YOU are the one coming on here telling the majority of folks they are wrong"

Majority, meaning you? I only questioned running tires way over recommended. I also said 'many' run thier suspension too stiff. Your ego decided this was pointed at you. You made up the rest.

"Running tires at their max and shocks UNDER their max isn't "overpressuring the system". "

I defy you to find one mechanical engineer that agrees with you.

"They were slipping.. at a much higher speed than lower pressured tires."

Accrding to you, against all logic, engineering and several billion miles of testig done by people who know a lot more than we do...

"I've tried what you suggest, and that setup doesn't work as well for my bike or riding style.. so I would call that a fail"

Obviously you haven't, since you have no idea what my setup is. Since I made no specific judgements about YOUR system, for all you know my bike is setup the same.

"ACTUALLY tested it and found it doesn't work as well... but then you come tell us we're wrong. That's still funny."

No what is funny is that you assume everything is about you, and that YOU constitute everyone.

"Tell you what.. I'll quit riding like I'm 10 when you quit posting like you are."

I have to respond in a way you would understand. If you want to talk in more technical terms, feel free to throw some in.

[Wildkat]

No I am not a moderator however, can we please get back to discussing the subject and not slip further down the slope of going after each other.

Thanks

I agree...

Keep it civil or the post will be closed.

If you two want to fight this one out... take it private.

[trbig]

Majority, meaning you?

Nope.. majority, meaning the majority. Go back and read what people have posted and you'll find 7 out of 10 are at the max or over with one going to try it.

Accrding to you, against all logic, engineering and several billion miles of testig done by people who know a lot more than we do...

Nope.. not according to me. According to testing done on these actual bikes by people who are just like you and I, against YOUR logic, and with their particular brand of tire, and riding exactly the way THEY ride.... which you won't find in a book.


Look.. just go back and read with an open mind and see how many are, by your account, screwing up. I doubt any of the people posting just automaticaly threw the max pressure in their tires and called it good. There's a lot of cumulative miles and years of riding here that you are dismissing.


By all means, I say to start with the recommended pressures and try raising and lowering them in a real world riding situation and find out what's best for you.. not what a book says, or what somebody else says. Nobody rides just like me, and nobody is going to ride just like you.. and trying them at the max pressure WILL NOT resemble a lesson in ice racing , no matter what some may believe.

Sitting in here and being convinced these people are all wrong and you are right even though you haven't tried it is like a kid hating broccoli.. knowing it's aweful.. and yet not ever actually having taken a bite. But.. even if they do try it at that point, their mind is made up already. If you don't have an open mind about finding a good combination for you.. stick with what you know and ride how you're comfortable with.


Tod

[trbig]

And... lol.

"Running tires at their max and shocks UNDER their max isn't "overpressuring the system". "

I defy you to find one mechanical engineer that agrees with you.

We don't have any mechanical engineers here, but I grabbed my boss walking by who is a physical engineer.

His quote: "I don't know what you guys are talking about, but how can you overpressure a system if you are at or below the maximum?"

Ron Brown, P.E.


There's a couple more I could run it by if you want?


Tod

[Montreux_Blue]

Road trip........... battle of the XSsssssssssssss.

of your back tires.