Always run at or close to the recommended pressure for your specific tire. It's recommended for a reason.
The max pressure on the tire is the at the load safety limit. Don't run above that pressure. Besides, you'll end up with quicker wear around the center line of the tire because it's running too hard and not compressing properly against the pavement.
I've been quite happy at 38/40. 40/40 is fine as well. I think the max front is 41 at the weight limit.
It's perfectly ok to try a pound or two one way or the other from the recommended. See what you like best.
My front Avon tire cupped on my 2007 Softail pretty bad on Okinawa. HD Service Manager there said it was because of the coral sand they used in the concrete on the roads. Funny it was always on just the one side.
I rather suspect the cupping goes across the tire, but because of normal wear, it it not nearly so obvious as it is on the tire edges.
To create rythmic scalloping takes a rythmic frequency. Something (s) working together to create a pulsating high load. Tire pressure has a direct influence on the tires resonant frequency. But fork damping has a strong influence on the frequency of the bikes forces on the tire contact patch. Braking is hardly ever smooth, also creating pulsing, strongly felt by the tire contact patch. Even the deflection frequently of the fork tubes themselves.
No claim of "the answer", just some observations on the forces that can readily create front tire cupping.
I rather suspect the cupping goes across the tire, but because of normal wear, it it not nearly so obvious as it is on the tire edges.
To create rythmic scalloping takes a rythmic frequency. Something (s) working together to create a pulsating high load. Tire pressure has a direct influence on the tires resonant frequency. But fork damping has a strong influence on the frequency of the bikes forces on the tire contact patch. Braking is hardly ever smooth, also creating pulsing, strongly felt by the tire contact patch. Even the deflection frequently of the fork tubes themselves.
No claim of "the answer", just some observations on the forces that can readily create front tire cupping.
Nope mine cupped down the whole one side of the tire. When you rolled it, it was real noticeable. I have a picture somewhere as I was almost afraid to ride the dam thing.
Well.... once they do cup it's pretty easy to un-cup them.
This works wonders and only takes a few minutes.
Jack the bike up, start the bike, and put it in 1st gear. Put the rasp on the ground facing up and lift it up to the tire.
Works awesome and has the tire running smooth as silk again in minutes.
Mine cupped pretty bad, but as it happened slow, I didn't notice the degradation in handling, until they were replaced.
Also, the cupped tires were annoying as hell with the buzzing noise every time you leaned off center.
Don't remember my Dunlops cupping quite as bad as the Metz, and I don't know that I'd use a rasp on the rotating tire either to even the tread out, but its an interesting concept.
I found out with a few of my bikes, BMW R1200rt, Goldwing and BMW 1200rs that tire pressure was a big factor. A few pounds can make a big difference with regards to how much tires will cup. Doesn't seem to be an issue with Ultra LTD.
01-20-2017, 09:38 AM
