free website stats program Tire Inflation 1 | Harley Davidson Forums

Tire Inflation 1

glider.

BOT Machine
Posted by "Caper" from the Dunlop website.

Importance of Motorcycle Tire Inflation Maintenance & Load Restrictions
As the world leader in motorcycle tires, Dunlop continues to be concerned about the lack of attention paid by many cyclists to proper use and maintenance of their tires, particularly when fitted to motorcycles intended for touring.

Dunlop technical personnel have attended touring rallies all over North America to collect vital data and give instructional seminars.

What we have observed at these rallies alarms us; many touring riders are not following proper tire maintenance procedures.

The requirements for proper tire usage are not complicated, but they do require consistent attention.

Owners and operators of motorcycles should closely monitor vehicle loadings to insure they are within the maximum loads and corresponding inflation pressures for their tires. This basic load and pressure information is clearly stamped on the tire sidewalls.

The tire does not support the load-the air pressure does. The manufacturer's ratings for the maximum load and inflation pressure are critical tire design elements. If not observed, the handling and performance of your motorcycle will be greatly affected.

We have checked inflation pressures at several touring rallies and found a high percentage of rear tires to be underinflated. In addition, weight checks of the rear axles of these motorcycles indicated a number of tires were loaded beyond maximum capacity.

Our inspections have not been limited to those cycles fitted with Dunlop tires; the situation exists for all brands of tires.

Regardless of the make of tire, this is a serious problem. Riders of motorcycles with significantly under inflated and overloaded tires will experience handling and steering difficulty. In addition, this abuse will result in disappointing premature tire wear and may cause catastrophic tire failure.

The addition of accessories, cargo, and dual riding to touring motorcycles aggravates the problems of overloading and under inflation. The excessive flexing that results from under inflation or overload causes buildup of internal heat, fatigue cracking and eventual carcass breakup resulting in complete failure. A consequence of such failure may be an accident with serious personal injury or death.

The appearance of stress cracks in the tread grooves is one indicator of overload and/or underinflation. If you find evidence of tread groove cracking, you should remove and replace the tire immediately. This damage is permanent and non-repairable.

Our inspection of tires of various style and manufacture at rallies and our subsequent testing have confirmed that under inflation (and/or excessive load) causes tread groove cracking and can result in more serious damage within the tire body. Uneven wear may also accompany under inflated use. Failure to heed these visual warnings can result in tire failure or blowout.

The use of trailers can also contribute to tire damage and touring motorcycle instability. Although most motorcycle manufacturers recommend against their use, a percentage of the motorcycles we have inspected were so equipped. The trailer tongue weight added to an already heavily laden motorcycle can fail a rear tire. The percentage of overloaded motorcycle rear tires found during our inspection would have been higher if trailer tongue weight had been considered. The forces of rapid acceleration and deceleration may also multiply the effects of trailer tongue weight.

To get the maximum safe use out of your tires and maximum touring enjoyment you should:
  1. Properly maintain all aspects of your vehicle in accordance with manufacturer's recommendations. Read and reread your motorcycle owner's manual.
  2. Never exceed the loading and accessories restrictions found in your motorcycle owner's manual, or the maximum load displayed on the tire sidewalls. Know your loaded vehicle weight!
  3. Check air pressure at frequent, regular intervals, particularly just before and during long trips. Always use an accurate tire gauge* and check pressures only when the tires are cold (i.e., wait one hour after running). We have found many cheap gauges to be off more than 5 psi, so be sure to use a top quality gauge and preferably one that retains the pressure reading until reset!
  4. Inspect your tires as often as possible. Look for irregular wear, any signs of cracking in the sidewalls and tread, blisters, knots, cuts or punctures. Immediately remove and replace damaged tires.
If in doubt, ask your motorcycle tire dealer to check your loading, inflation and tires. Remember, your tires stand between you and a serious accident.

For touring motorcycle loading, follow these general guidelines:
  1. Light loads-single rider with some luggage (up to 200 lb. total)-minimum tire pressure of 32 psi front and 36 psi rear must be maintained.
  2. Heavier loads-dual riding and/or luggage (from 200 lb. total up to maximum motorcycle capacity stated in the owner's manual)-pressure of 36 psi front and 40 psi rear must be maintained.
Please Note:
For any dual riding or fully loaded use, 40 psi must be maintained in all Dunlop rear tires fitted to touring motorcycles.

In addition to following these recommendations, notice what your tires are telling you while you're riding. If your steering response is slow or mushy, or if cornering and braking response is heavy, there's a good chance your tires are underinflated. Vibration or wobble may signal that actual tire damage has occurred and failure is imminent!

If you conscientiously follow our recommendations, you will enjoy better, longer, and safer tire performance and many, many miles of touring pleasure.


loadcarrying.jpg


Tires offering different load-carrying capacities are available. Consider carefully the weight of the motorcycle, the weight of any optional equipment and whether it will carry passengers. Remember, the load- carrying capability of the tires is also reduced by under inflation. It is possible to overload a tire even though it is the size specified by the motorcycle manufacturer. Maximum loads and corresponding pressures are indicated on the sidewall of all Dunlop street tires.

Never exceed the accessory restrictions and vehicle load capacity found in the motorcycle owner's manual, or the maximum load molded on the tire sidewall. Before a trip, be sure to determine the total weight of luggage, equipment, and rider(s) to be added to the motorcycle.


Trailers may contribute to motorcycle instability, grossly exaggerated tire stresses and overload. Such stresses and overload can cause irreversible damage resulting in sudden tire failure and accident. Dunlop does not recommend the use of trailers, nor warrants tires used on motorcycles fitted with trailers.

Sidecars should not be fitted unless approved by the motorcycle manufacturer.

Tire Tips
 
Thanks Mr. Data. This is great information. I know I was a little confused on correct pressures under different situations. This clears it up and make a good point on how critical it is to both tires and more imoprtantly safety. Thanks again for posting.
 
Since we are on this subject, the article mentioned getting a quality air gauge.

I would not know a quality gauge if I saw one. I buy mine at the local Canadian Tire Store. The accuracy of a tire gauge has always concerned me since I stared riding.

Any recommendations regarding a brand name ??
 
Riding a police bike and in the schools I have attended we suggest 40psi on our bikes. You would be amazed at how much difference there is in the handling of the bike if it is below 35lbs. I can get on my work or personal bike after knowing what it feels like in a slow maneuver turn and without doubt tell when it is low. I rode at another police department for 5 years and then went to work where I am now and I preech to the other guys about tire pressure all the time. Great topic. Mark72
 
Once again Mr. Data comes up with the goods.

Thanks for this vital and potentially life saving info.
 
Maybe I skipped thru it too quickly, but which recommended pressure do you use:
the one on the bike label, or the one on the tire? I have E3's so I would assume the pressure # on the bike label would be for OEM HD tires? Is this right ??

Thanks
 
Maybe I skipped thru it too quickly, but which recommended pressure do you use:
the one on the bike label, or the one on the tire? I have E3's so I would assume the pressure # on the bike label would be for OEM HD tires? Is this right ??

Thanks

Over the last number of years I've been running at or a pound or 2 less than the sidewall pressure(inflated while cold)but mostly at sidewall pressure rather than the manual recommendations front and rear and have been getting better mileage out of my tires than my buds are. I find Harley's specs are a little less than optimal.
I'm running E3' too and for the first 5000 miles had them at 40lbs front and rear(sidewall pressure), the handling and cornering was great in good and bad weather.
Last week when I checked them before a ride around the Island they were both down a couple of lbs so I pumped the rear up to 40 and left the front at 38, handling was good but getting a bit of wallow when cornering going over expansion joints on the overpass I ride everyday at 75-80 MPH. I'm going to pump the front back up to 40 to see if it makes a difference. (wasn't happening at 40/40)
I feel you have to experiment a bit to find optimal tire pressure for your ride , but never exceed the sidewall rating and always check and inflate them when they are cold.
Harley seems to send their bikes from the factory set up for a 5'10" 180lb rider which I'm not.
 
Back
Top