Street Tire Pressure And Street Tire Wear

[DUNLOP-RTS]

Since we're talking pressure - what impact does it have on street riding wear? Most bikes today seems to be recommended to run 36F and 42R. Will life deteriorate markedly if one was to run 30/34 for instance?

 

 

 

Certainly you want to use the recommended tire pressure that is in the owners manual for your bike. There is a reason for that recommendation.

 

But logic also applies here. if you went lower you would get less stability, and on the street stability is important with all the cracks, seams, stripes and possible holes in the pavement. Running low pressure on an N-Tec tire on the street would be foolish, given the high likelihood of bending a rim over bumps and holes.

 

And with lower pressure on a street tire also comes increased wear. How much wear? not sure, but it will wear quicker and the tread blocks will start cupping sooner, especially on the front which has dynamic forces in one direction only. The rear being more even since it has both breaking and engine forces, thus smoothing out the wear.

 

My feeling is that any increase in grip you are looking for is not worth the loss of stability on the street. Some riders may consider themselves at race pace in the twisties, but honestly this is not the reality, the pace on the twisties (however fast it may seem), is not on par with fast track speeds. The comparison is one of ego's and not corner speed.

[faffi]

Thank you for taking the time to make an elaborate reply Actually, the question about lower pressure was two-fold but not about grip; it provided more comfort and I'm also a bit slack about checking, so it isn't unusual for me to run low on pressure from time to time.

[spthomas]

Since we're talking pressure - what impact does it have on street riding wear? Most bikes today seems to be recommended to run 36F and 42R. Will life deteriorate markedly if one was to run 30/34 for instance?

Certainly you want to use the recommended tire pressure that is in the owners manual for your bike. There is a reason for that recommendation.

Thanks for this information- I had wondered about that too. The higher pressure I imagine would keep the wear in the center of the tire and less spread out. It seems one of the features of the Q2's was the long-wearing compound on the center, so a too-low street pressure would spread the wear beyond the center zone, right?

[DUNLOP-RTS]

Since we're talking pressure - what impact does it have on street riding wear? Most bikes today seems to be recommended to run 36F and 42R. Will life deteriorate markedly if one was to run 30/34 for instance?

Certainly you want to use the recommended tire pressure that is in the owners manual for your bike. There is a reason for that recommendation.

Thanks for this information- I had wondered about that too. The higher pressure I imagine would keep the wear in the center of the tire and less spread out. It seems one of the features of the Q2's was the long-wearing compound on the center, so a too-low street pressure would spread the wear beyond the center zone, right?

 

I was thinking only about side wear when lowing the pressure.

 

If you were running low pressure on the street, Riding straight up and still touching the soft sides of a Q2, you certainly would have way to low pressure, go back to the stock pressure.

 

Again, lower pressure= less stability. when you street ride you need stability.

 

There really is not much on the plus side for lowing pressure for the street.

[Cobie Fair]

Steve--good points, but I'd like a little clarification on this.

 

We have had many that have had their pressures up 36-38 front, and 42+ rear.

 

I understand your street riding comparison, but don't we still want to get very good traction and with high numbers (often recommended, and as I understand for max conditions--like 2 up, baggage, etc.).

 

I personally would sacrifice a bit of tire wear for traction, after tossing my first motorcycle down the road from letting the tires get too used.

 

CF

[DUNLOP-RTS]

Steve--good points, but I'd like a little clarification on this.

 

We have had many that have had their pressures up 36-38 front, and 42+ rear.

 

I understand your street riding comparison, but don't we still want to get very good traction and with high numbers (often recommended, and as I understand for max conditions--like 2 up, baggage, etc.).

 

I personally would sacrifice a bit of tire wear for traction, after tossing my first motorcycle down the road from letting the tires get too used.

 

CF

 

 

If you are having grip issues on the street with the recommended pressures, I would submit you are in a very very slim minority of riders. (we are assuming the tires are not worn out)

 

For legal reasons you will only see recommendations from bike manufacturers and tire manufacturers that sight the owners manual pressures (I am in this category). Because, for the majority of riders, this does apply and is best for safety.

 

Having said that, you can refer to earlier posts that give procedures for racetrack pressures.

 

This is where we must separate the theory from the practical application. We all want more grip, but do we really NEED more grip than what is being supplied? Its much like being thirsty and always asking for a larger glass of water only to find yourself with a 55 gallon barrel of water, that you can't maneuver and that you can't drink. So were you really that thirsty?

 

In theory we always want more traction, but do we really need to lower pressure to to get more, or is the traction sufficient to not warrant a pressure change and thus keeping more stability?

 

The answer is a personal preference. For me, I prefer the higher pressures, close to the recommended. Back in the day (when I was fast), I rode 2 up and kept with the front of the pack or lead it through every canyon ride. Never did I slide the tire. Being smooth, having proper throttle control and not being a squid, made for a good fast ride with no traction issues and lots of stability.

 

If a rider, running recommended street pressures, is sliding his tires on the street, while having proper throttle control, he would be in the minority and should reconsider his actions on a public road and his personal safety. That is the point a rider should personalty have the realization he needs to be on the track and not trying to squeeze more from his street tires on the street.

 

Keeping it real, we must grasp that the street and track are 2 different environments, each with its own barriers. Some things that apply to track may not be as important on the street.

[Cobie Fair]

Excellent response Steve. Really brings to mind how close I have ever come to sliding around on the street--except for hitting something slippery (or not warming the tire), I'd say never. But there are lots of guys that are willing to go faster than I am in street conditions.

 

I'd like to know how many of you have 2 different "settings" for you pace, street and track? But, sounds like another thread, off this topic.

 

CF

[sslowmo]

I run 35 psi F/R on street. For track 30-31F/28-29R. I figure the higher pressure's for the street would also help prevent damage to my rims on sharp bumps. Like the one's just before you roll onto a bridge.

Aaron

[Cobie Fair]

I run 35 psi F/R on street. For track 30-31F/28-29R. I figure the higher pressure's for the street would also help prevent damage to my rims on sharp bumps. Like the one's just before you roll onto a bridge.

Aaron

 

I had run your track numbers on my Q's shod ZX-9 on the street--didn't seem to have any stability problems. I always wanted a little more margin, err on the side of more traction, but I'm thinking about going up a few pounds after all these posts.

 

CF

[dbiasotti]

Excellent response Steve. Really brings to mind how close I have ever come to sliding around on the street--except for hitting something slippery (or not warming the tire), I'd say never. But there are lots of guys that are willing to go faster than I am in street conditions.

 

I'd like to know how many of you have 2 different "settings" for you pace, street and track? But, sounds like another thread, off this topic.

 

CF

 

Very good winter day reading about all the excellent tips on tire pressures from Steve and others.

Especially the points of sliding/ race pace on the street; very valid point - two entirely different environments and anyone going race pace (or even thinking they are) are destined for a limited life span or at best limited time riding motorcycles .

Cobie's question especially piqued my interest about different settings street /track - yes, most definitely.

And I would add that for different street riding, yet even more or different settings.

Very much agree pressure settings are a trade off of stability, tire life and and heat build up. I would put out there that for street tires, traction is not as affected as I think Steve was implying in his post and stability is more important to maintain. I have slid on the street but typically small, brief slides and almost always due to the road surface or "stuff" on the road; not a fault of the tire or exceeding the limits of traction of the tire (refer to the point of riding at race pace).

Track settings have been addressed and should definitely be lower than street.

Street settings are in the range of 34-38F and 35-40R depending on bike and mfg recommendations and you should definitely follow your mfg's recommended settings. As Steve said recommended for a reason, but ...

For different street riding you should vary these settings as in;

- two up with luggage (heavier load) need to raise the pressure especially rear per owners manual guide due to heavier load.

- single, regular riding commuting go with std settings

- single sport ride in the twisties you can lower settings a couple #'s for max traction, but will shorten tire life

- I do 24 hr and multi-day endurance rides (I guess what you would call extreme sport touring of 1,000 miles or more /day). For these rides I bump my settings up to typically 40 frt and 43 rear.

I run tire monitors that give me press and temp readings and have definitely seen a correlation between sustained riding at "sport tour speeds" for several hours between stops and elevated tire temp vs life. Higher starting cold settings will keep the temps down and improve tire life. Lower starting cold temps will result in a significant rise in press (+10 psi rise or more) and resultant much higher temps. This results in an overinflated/ overheated tire, especially the rear which is taking all the load, not a good situation.

So yes different riding; different environments should most definitely use different settings. I think mainly has to do with how long you are going to be maintaining a heat load on your tires.

[Motostark]

Excellent response Steve. Really brings to mind how close I have ever come to sliding around on the street--except for hitting something slippery (or not warming the tire), I'd say never. But there are lots of guys that are willing to go faster than I am in street conditions.

 

I'd like to know how many of you have 2 different "settings" for you pace, street and track? But, sounds like another thread, off this topic.

 

CF

 

I will preface this by saying that I have limited track experience.

 

However, on the street, I use 42/36 as per owners manual. I've played around with pressures on the street, and agree with the advice that one should follow the owners manual.

 

When I was on track, the guys were recommending 30/30 (Im currently running PP 2CTs), and I have to say, they felt amazing and very reasssuring. When I tried this on the street for fun, I wasn't happy with the results.

 

Cheers.

 

S.