ganchan

I read on the Sheldon Brown site that generally speaking, the rear tire should carry about 10% more pressure than the front because it tends to bear more weight. I've always inflated my tires as close to equal as I could get -- I don't load anything on my bike other my own big ol' butt. (I do sometimes wear a lightweight backpack.) Should I change my ways?

For what it's worth, I ride a Simple Seven cruiser with 26-inch balloon tires rated at 45-65psi. I tend to keep them around 50.

waldowales

How dare you question Sheldon? Repent, before it's too late!
Actually, if you think about it, it makes sense. Heavier load, higher pressure.

bradtx

While good advice, it is generally aimed more towards those using smaller and narrower tires. Certainly worth experimenting with.

Brad

PS I will raise air pressure in the rear tire on my touring bike when I've a load approaching or over 20 lbs.

dsbrantjr

Here is a link to a article which gives guidance for inflating tires according to actual weight on the wheel; it is a simple measurement to make or the author gives guidelines to estimate. www.bikequarterly.com/images/TireDrop.pdf

FBinNY 

Yes, you might change your ways, but it's not like it matters much. If you want to be a technically correct purist, here's a guide to optimal pressure based on your weight and tire width.

milkbaby

Don't air your tires up to be rock hard and you'll see there is a difference in how much tire drop there is between the front and back tires when you have them aired up the same pressure. It is very apparent visually that the back tire experiences a lot more drop at the same pressures.

Mr. Fly

While that guide is certainly a good starting point, it may lead to front tire pressures that are a bit too soft during off-saddle sprinting events. Remember, their recommendation is for when the rider is seated and spinning along. I find that adding at least 10-20% more to their recommended pressure for the front tire yields better results for me; their rear tire pressure recommendation is usually spot on though.

FBinNY 

Like all rules of thumb, it is only a guide. There are other variables, such as pavement condition. Going to slightly higher pressure helps on very smooth roads, and even the 15% pressure may be slower and cause poor handling on rough pavement.

Use the formula as a starting place, then tweak it according to your unique circumstances.

cplager

Hi,

You want the ratio of your tire pressures to be the same as the ratio of your weight distribution. Meaning if you have 55% of the weight on your rear wheel, you want the ratio of your tire pressures front/rear to be 45%/55%.

You bring up a good point: When you are out of the saddle, your weight distribution changes. If possible, try to calculate the weight distribution when you are out of the saddle. This will give you another set of ideal tire pressures.

In the end, your idea of just 10-20% more is probably as good as anything else.

Cheers,
Charles

Garfield Cat

Over inflated tires (for your body weight) on a fast and long descent might make the ride a bit jumpy.

dsbrantjr

There's an Android app for that: https://problemsolversbike.com/blog/c..._tire_pressure

dsbrantjr

Here's an article by Frank Berto which expands on his Bike Quarterly article and adds information on mountain bike tires which takes into account their different construction from road tires: https://www.bccclub.org/documents/Tireinflation.pdf