Tire Pressure

[Guest]

Yes i apologise for this question in advance... this is slightly embarrassing to ask...

But, what pressure should i be running my tires at? The Front says 41psi on it, rear 38... However this is max psi, and i didn't think i would need to put it that high

At the moment I'm not doing long rides, just practicing around the streets and occasionally a cruise along the beach. The weather down here is pretty cold (for me anyway!) around 15deg max in the afternoons, 4-6deg in the morning...

[tkent02]

search for the ten percent rule.

[razor02097]

Yes i apologise for this question in advance... this is slightly embarrassing to ask...

But, what pressure should i be running my tires at? The Front says 41psi on it, rear 38... However this is max psi, and i didn't think i would need to put it that high

At the moment I'm not doing long rides, just practicing around the streets and occasionally a cruise along the beach. The weather down here is pretty cold (for me anyway!) around 15deg max in the afternoons, 4-6deg in the morning...

There should be a decal or a plate on the chain guard that will tell you the recommended pressure.

[nikosg]

thanks gents.

[tkent02]

There should be a decal or a plate on the chain guard that will tell you the recommended pressure.

the recommended pressure for 1981 tires is not at all the same as the correct pressure for modern tires. The technology is very different.

[Steve]

There should be a decal or a plate on the chain guard that will tell you the recommended pressure.

However, that recommended pressure is only valid if the current tires are rated for the same weight and maximum pressure as the originals.

With the improved tire technology, the tires themselves will handle different weights at different pressures, so follow tkent's advice:

search for the ten percent rule.

Searches are always good, but sometimes frustrating, so ...

Pick a nominal pressure, say 30 psi. Set both tires to that pressure when they are cold. ("Cold" only means they have not been ridden for about eight hours.) Go for a ride to warm them up. 20-25 miles should do nicely. Check the pressure again, you are looking for a 10% increase, or 33 psi. Pressure goes up because the tire flexes as it rolls, the flexing causes heat, which raises the pressure. If your increase was more than 10%, the tires were flexing too much, indicating they need more air. If your increase was less than 10%, they were not flexing enough, meaning they started with too much air. When the tires are 'cold' again, adjust pressure about 2 psi, go for another ride.

Please note a couple of items here.
1. Some brands of tires have a max pressure of 32 psi, others are 36, still others are 41. If each of them is rated to carry the same weight at those different pressures, they will require similarly different pressures to carry the lesser weight that you will ask them to. In other words, just because your Dunlops needes 28 psi does not mean that your Avons will need the same, so check your pressures if you change tire brand.

2. If you do much riding 2-up, you will need higher pressure, especially on the rear tire, so there will be more testing to make sure you have the proper pressure for 2-up riding.

.

[Missile99]

The 10% rule works great as they say. I am close to getting the cold pressures right and the bike handles great. My BT-45's say 42 psi cold. I weigh 160. The bike has some junk in the trunk (not literally but they aren't necessarily lightweight) and I tried them at 42 once for the hell of it. It felt like bicycle tires or rails. No flex. Felt weird to lean over. Like Steve says don't listen to the factory label either. Tires were different 30 yrs. ago.

Now I'm near the 10% increase in pressure warm and it feels great. About 30 front and 34 rear for me.