I attended a fascinating tire seminar by an expert engineer at Road Rider. This is what I learned (long):
Who: Ron Bowen is a veteran in the motorcycling industry. He has worked for both Bridgestone and Dunlop, and now currently travels the country as Parts Unlimited's Brand Manager for both Pirelli and Metzeler. He has been in this role for over ten years. He was a vehicle dynamics engineer for motorcycles and cars for about 18 year prior to Parts Unlimited. He has visited 49 tire factories globally and works with 73 reps in his huge area of responsibility.
First thing: Do NOT run car tires. Diameter is ever so slightly different, mounting different. 2 Technicians were almost killed testing them. The tires will spin on the rim under hard acceleration. . That video someone likes to post of the testing of the car tire under extreme loads? That video is only relevant if it’s mounted on a motorcycle rim.
The cost differential in MC vs. car tires is due to construction, and the fact that MC tires are sold as a very small fraction of car tires. That video someone likes to post of the testing of the car tire under extreme loads? That video is only relevant if it’s mounted on a motorcycle rim.
Speed ratings are based on a sustained 15 minutes at the rated speed.
Mixing brands/models of tires is not recommended due to different properties of 3 materials used: rayon, polyester and nylon
Age – 3-4 year old tires are absolutely fine. He gave an example of a Carlos Checa on 3 year old tires setting lap records. And motorcycle race tires get cold cycled on airplanes vs. street tires shipped to distributors. Tires older than 10 years old should be replaced. In other words, if your date code on your new tires is several years old, it’s a non-issue. The date coding was standardized in 2002 or so.
Tires need about 100 miles to mechanically abrade the mold release oil off the tread. It’s not an added substance; it’s just the oils that occur during the mold process from the tire itself.
When a bike is loaded: Every 1lb of under inflation = a 10 degree increase in internal temperatures. Said it’s possible to approach failure temperatures if severely underinflated. Radial tires are actually worse than bias ply for low pressure flex. The air is the heat sink, not the tread.
For ALL bikes except track day sportbikes should run MAX PSI at all times, front AND rear. He said this will optimize wear & handling. Once you replace the tires, use the max PSI on their sidewalls, no longer the bike manufacturer recommended pressure.
(He did later tell me that the guy said to run OEM tires at the bike manufacturers recommended pressure) So it's a toss up if you ask me. But sounds like they should be at Harley's MAX if nothing else.
Speaking of tire inflation, his favorite gauge is Accu-gage. It’s a dial type, and I bought one that night for $22.95 and the beauty is it has a 90-degree head for taking pressure readings under the saddlebags and rotors. Interestingly the only dial type tested with a high rating by Consumer Reports was Intercomp for $56.
Nitrogen in tires – this surprised me. He stated it was the elimination of moisture that was the advantage and hence heat management, and using it could realize a 10% increase in tire life.
Chemical grip is improving which translates to higher mileage obtained. He said 30,000 mile motorcycle tires are coming, if not now out already.
For cleaning wheels and tires, he likes Bike Brite.
It was fascinating, the guy was a wealth of information.
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Topic: Air pressure in tires, whats the consensus? 1 up & 2 up riding (Read 12924 times)