High-speed stability off our CB1100

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The Dunlop tyre on mine started to wear abnormally. Honda dealer said they had problems on quite a few bikes running those tyres. I replaced it with a Pirelli sport demon and fitted a small screen. Have had the bike to 190km/h with no probs.

Hey Tezza, the Dunlop OE tire on the front of my bike is cupping a bit at only 2,200 miles. Is that the same abnormal wear you were getting?

Hey Tezza, the Dunlop OE tire on the front of my bike is cupping a bit at only 2,200 miles. Is that the same abnormal wear you were getting?
try pumping the front tire pressure by a couple of pounds using the air gauge you normally use, say to 38 pounds and see if that doesn,t straighten it out.

No, don't do that. Tires are designed to work properly within a certain temperature and pressure range. 36 psi is the maximum pressure for our motorcycle.

Increasing the pressure will decrease the size of the contact patch and decrease the running temperature of the tire.

Traction is dependent on the size of the contact patch and the temperature of the rubber compound. So, you will reduce available traction by increasing the pressure beyond the recommended amount.

For example, when we take a motorcycle to the racetrack for a track day or school, we always decrease the tire pressure to allow for the increased pressure buildup in the tire due to the high speeds creating more heat than we would get on the street. See this link:

http://dunlopracing.com/technical-info/

The same is true for automobile tires. I had an educational experience with this last week; I increased the tire pressures in my high-performance sedan to get a bit better mileage. When I hot-footed it around a traffic circle I'd gone around many times before without issue, the rear tires broke loose, and this is with a front-wheel drive car where you'd normally get understeer. I was running 40 psi instead of the recommended 35. Mistake.

Fortunately I was driving a car and not riding a motorcycle where the loss of control would have likely been a lot worse than just getting sideways.

36 psi is at the top of the normal safe range for the CB1100; we can actually go a bit lower if the load on the bike is less than maximum. I run my front tire at 34 and the rear at 36 for mixed conditions of freeway and backroads. I run my sportbikes at 32 front/34.5 rear on the street, whereas at the track, especially if it's cold, I might bring them down to 29 front/28 rear.

If your bike is truly unstable you'd be better off finding out the real cause rather than trying home-brewed solutions that can create problems rather than solve them. If you just add a couple of psi to the front tire and then go out and test it again by running it up to 160 kph, if you've made things worse or have to suddenly turn or stop the bike, you might not have a stability problem, you just may have a problem with your medical insurance.

Any good technician will recommend that you:

- check the tire balance on a machine
- check the steering head bearings
- check the suspension settings
- check weight and loading
- check for a defective tire/wheel/wheel bearings
- checkup from the neck up because why are you going 160 kph?

OK, that last was a joke but seriously, get your bike looked over; I've run mine up to 110 mph and didn't experience anything that I wouldn't have expected given it's not a racebike. Maybe there's an issue with yours that needs to be corrected.

The Dunlop tyre on mine started to wear abnormally. Honda dealer said they had problems on quite a few bikes running those tyres. I replaced it with a Pirelli sport demon and fitted a small screen. Have had the bike to 190km/h with no probs.

Hey Tezza, the Dunlop OE tire on the front of my bike is cupping a bit at only 2,200 miles. Is that the same abnormal wear you were getting?

Hey Tezza, the Dunlop OE tire on the front of my bike is cupping a bit at only 2,200 miles. Is that the same abnormal wear you were getting?
Pauley,

I have 3800mi on my Bridgestones and there cupped. I bit more on the left then the right. Most roads are banked left to right causing the tire to wear more on the left. I started noticing it around 2500 mi. This is normal since are tires are rounded not flat. Proper inflation and change the front out at 5000mi. ( I always change both at the same time )whether there worn or not. New set of tires will get rid of road vibration too.

Good advice. I had cupping on my Dunlops. Some tire/bike combinations just do this. Normally it can be corrected by going to a different brand/type of tire. Exceeding recommended pressure is verboten. As I mentioned a while back, I went to the bias-ply Bridgestones, running the 150/70 rear. Absolutely no issues, no cupping, no problems. 34F/36R for standard weight (160 pound) rider.

Also, it should go without saying that you want to confirm the accuracy of your pressure gage. Digital gages are not any more accurate than analog gages, since digital gage uses an analog transducer anyway and the output is simply converted to a digital display. But find a good reference gage that is known to be correct and use that for checking your accuracy.