Tire pressure

[AmyF27]

I had been going by the bikes sticker 28 PSI front tire 33 PSI rear tire.  Based on my tires my shop set them at 40 PSI each. My tire sidewalls both say 41 PSI cold Max.  This morning when I checked they were both about 36 PSI cold. Last night it felt almost like they were a little over inflated I wonder if just taking down a couple PSI would help. 

[Connie14]

Check your owners manual.  The tires maximum cold pressure may not be the same as your bike's optimum tire pressure.  For example, my bike's optimum tire pressure is 42psi, but the sport bikes running the same tires run a much lower pressure.

[Tonik]

A couple of pounds below the max on the sidewall is what I have always run....cold.  You are on a cruiser, go with that. You could drop down a little more than that, maybe 5 lbs because your bike is lighter.  Things change a bit on a sport bike, but you don't need to worry about that.

Manual suggested pressure is a crap shoot. Often the folks that write those are on drugs when they pick a number.  Mine says 26 for a 850 pound bike...which is total insanity.

[2talltim]

Your going to get suggestions that will be all over the place. Like what the tire says or what the owners manual or swing arm says or this is what I do. I don't know there is a correct answer. I do what my what the bike maker says to run like Mike mentioned and its perfect for me. But like Jim said that didn't work for his.  

Edited June 22, 2016 by 2talltim

[zx3vfr]

The pressure listed on the sidewall is the max cold pressure.

You should really use what the manufacture suggests, maybe a little more if you weight more than 150-170# and by a little more 1-2psi.

Every dealership has over inflated my tires and I make it a point to the service manager that is not proper procedure and how do they think their manufacture reps would react that their techs are over filling recommend pressures.

[what]

1 hour ago, Tonik said:

A couple of pounds below the max on the sidewall is what I have always run....cold.  You are on a cruiser, go with that. You could drop down a little more than that, maybe 5 lbs because your bike is lighter.  Things change a bit on a sport bike, but you don't need to worry about that.

Manual suggested pressure is a crap shoot. Often the folks that write those are on drugs when they pick a number.  Mine says 26 for a 850 pound bike...which is total insanity.

They're trying to keep you slow and lethargic in the corners. 

[AmyF27]

I lowered the pressures to appx 34 F,  35 R.  I then felt it was a little to squishy of a ride.  It seems it's better closer to the tire sidewall Max.   

[Bubba]

Tire pressure threads are a whole lot like "What oil should I use?" threads--everyone has an opinion.  One thing that NEVER seems to get mentioned is that motorcycle tire pressure 1) isn't some fixed-in-stone number that you should set-n-forget and never change, and 2) is WAY more important to check and adjust on a bike than on a car.  The sidewall pressure number isn't any sort of recommendation from the tire manufacturer--it's the MAXIMUM cold pressure that should never be exceeded for inflation, not what you should set your pressure to.  Your owner's manual and the sticker on the swing arm/frame should have the recommended tire pressures listed for your bike, but this is applies to the OEM tires only, and thus could change if you switch to non-OEM tires.  Air/road surface temperatures also affect how much pressure you should run, so obviously it's a good idea to check your pressures before each ride.

As a general rule, you should start with your pressures set to the recommended level and then experiment around that.  Hotter temps, higher speeds, and heavier loads typically mean increasing pressures anywhere from 2-5 psi (up to the max sidewall number).  So, two-up riding, loaded touring, extended x-way miles mean bumping up your pressures.  Cooler temps (i.e., winter riding), especially when doing spirited riding in the twisties, means lowering your pressures 1-5 psi for better traction, although this is not necessarily true if you're simply doing easy cruising.  Also, realize that lower pressures mean softer tire sidewalls, which results in more flex and means they heat up more quickly and this typically results in shorter tire life.

Different styles of tires are affected more or less by pressure changes, too.  A high-performance road tire will have a more responsive tread and sidewall construction (for max traction) and respond to small pressure changes dramatically.  Pure race tires don't work well on the street because the rubber compound needs to be "hot" for max traction (thus, tire warmers you see at the track) and typical street speeds don't generate sufficient heat in the tread to maintain max performance.  Tires designed for heavy cruisers, touring bikes and ADV bikes usually have a much more stout sidewall construction to support the weight and harder tread compounds for longer tire life, and so tire pressures don't affect the performance as much.

Edited June 23, 2016 by Bubba

[ReconRat]

Tire pressure is based on tire size vs vehicle weight plus rider(s), per weight percent distribution front and rear.

All are based on science, the Department Of Transportation manuals that show what pressure per. Most vehicle "plates and stickers", show the highest max pressure for a full load.

Which means one rider instead of two can reduce pressure for a better ride. Normally this is the rear tire that lowers pressure. Not so much the front tire.

There are some noteworthy guidelines. Never reduce pressure below 26psi cold. No tire is designed for less. Yes, some off road tires can get away with less.

The pressure numbers on the tire, are the tire's max. If that is less than the recommended pressures per the total weight, then the tire is too small or cheap.

Example: For me, on a Honda, I can reduce the max pressure shown on the sticker for two riders, by 25% each tire, for one rider. I do not lower the front tire pressure quite that far. That would be a bit too low. 36psi front recommended. 27psi is 25% less, and just too low. 30-32psi min up front is more acceptable. If riding with a passenger, both tires should increase pressures back up to the higher numbers.

And caution is advised, since I've seen even manufacturers get recommended pressure data wrong. Or they goof their vehicle design, causing them to try for a ridiculous set of pressure numbers.

edit: I'm also ok with the max 36psi in the front tire, and 25% less in the rear tire. Less bumpy ride, and not so squishy feeling on the handling.

 

Edited June 23, 2016 by ReconRat

[jschaf]

Don't go with what it says on the tire. This is the absolute maximum pressure that the tire will withstand. If you ride a moderate pace in the corners stick with what it says in the owners manual for the bike. You will get the longest life from the tires that way. Both my bikes manuals call for 42 R, 36 F & I find this good up to about 75% pace (commuting). At track pace 30 R, 30 F is a good start for street tires heat up to grippy temperatures. If you are somewhere between commuting pace & track pace you will have to interpolate & adjust tire pressure accordingly.

[Vagabound]

They always over inflate tires when changing. For the exact reasons you see in this thread. Everyone uses their own pressure. Easier to take air out! It's a good practice in my opinion.