I am pretty sure the difference between 38 and 40 psi is splitting hairs when your typical pencil type pressure gauge is likely only accurate to plus or minus three pounds if you are lucky.

 

The pencil type gauge is actually quite accurate and likely to be as good as anything other than very expensive alternatives. I read a comparison test of gauges a few years ago and they came out best value! Also using the same gauge all the time ensures you always restore pressures to the same standard. I have never used any other type. Just buy one with a decent brand name on it.

 

I have a good tire gauge and when I got home from having the new tires installed, I let them cool and checked them to see if my gauge saw the same as his. I also took my gauge and compared it with a tire store near me.

Thanks to all for the info!!!!

 

I also check them again after a couple of hundred miles. They seem to bed in and often lose a pound or two. I think of them as a bit like a dog shaking itself after fitting its collar before taking it for a walk!

 

After getting my POS 407 front tire replaced and buying a new rear I run 40/40/ Front and Rear. Works for me

 

I run max that I can in most situations. With my Avons I ran 40 and 46...got 22K+ out of the front and 16K on the rear. With my Dunlops I run max sidwall pressure and so far have 12K on the set with little appreciable wear. Suspect (no guage used) that I have another 6k at least on the tires.

ALWAYS better to run a little over than a little short in the pressure dept

But to each his own

R. Todd

 

Why would motorcycle tire air pressures be any different than cars or trucks?

Sounds like there are two basic different approaches to tire pressure. Follow the maual 36-38 Front, and 40 rear, or some percentage of tire maunfacturer sidewall maximum pressures.

I always thought that the owners manual (aka frame sticker) was what the manufacturer recommended as the best compromise between tire life and ride quality?

Isn't anything else "messing" with the factories pre-determined "best ride and maximum wear" calculations?

I use factory recommended tire pressures, as the tire manufacturer doesn't know what bike your putting their tire on, or what loads your riding with, and therefore can only tell you what the maximum allowed pressure would be for their tire, regardless of load on the tire.

 

I checked out my tire psi max and it reads 40 psi max. I read that some of the guys ride at 40+ psi. Are those tire's max psi higher than 40? Just curious!!

 

They are not!

The figures in the manual and on the frame sticker were put there by the factory and relate to the tyres the vehicle came with when it was new. As soon as that tyre is superseded by the tyre maker, or we choose a different brand of tyre, those pressures get replaced by the figures for the 'new' tyre, although they may be the same numbers.

For later types or different brands of tyre consult the tyre maker. On their website Avon give their recommended tyres and pressures for your model of Harley. The others probably do too.

The factory can only make recommendations based on averages. None of us here on HDF are 'average'! I have adjusted tyre pressures for all the bikes I have owned since early in my riding career. A couple of pounds either way can often improve handling or comfort, also improve tyre wear. But these things will vary between riders, so the figures in the handbook should be considered a guide, not cast iron.

When riding two up, except for short trips, I always adjust tyre pressures and suspension settings. These ensure the bike rides just right, handles and brakes properly. Adding a passenger and luggage for that grand tour in the case of my wife and I adds over 20% to the weight of just me and the empty bike.

Surely, compensating for these sorts of factors is not 'messing'!

I can't speak for all tyre makers, but most if not all of them give tyre model and pressure recommendations for your vehicle, just check the website of your preferred brand. If need be, write to them. Harley doesn't know those things either, so their figures are only a guide!

I wrote to Avon about this. They told me that 40psi is an industry standard and what that writing on your tyre is telling you is that at 40psi the load figure given is the maximum load you should put on it. It is not telling you that 40psi is the maximum pressure the tyre can be used at, nor that the load given is the maximum load permissible. Avon told me 50psi is the maximum permissible pressure for Avon Venoms (I didn't ask about other models they make). Other data is available on their website, as it probably is for all other brands.

I gave the figures I use on an earlier post in this thread.