Wheelspin on acceleration

[Zafirovp]

Hi all,

I am a new rider, my bike is 97 Cat with Bridgestone battlax bt021's on it. I have plenty of tread on the back tyre, however on hard acceleration I get really scary wheelspin. Today I could smell burned rubber and it is happening at about 6-7000 RPMs at second gear. If the asphalt is new I can accelerate even to redline with no issues, however on old road I get this scary wheelspin. Is this normal or do I need new tires or better throttle control? Am I supposed to let off the throttle immediately or just to reduce it a little bit? I am afraid that the bike will go sideways at some point.

[vashtsdaytona]

the thundercat is not really known as a tire turner.

how much pressure are you running on that tire?

[MadYZF]

Hi all,

I am a new rider, my bike is 97 Cat with Bridgestone battlax bt021's on it. I have plenty of tread on the back tyre, however on hard acceleration I get really scary wheelspin. Today I could smell burned rubber and it is happening at about 6-7000 RPMs at second gear. If the asphalt is new I can accelerate even to redline with no issues, however on old road I get this scary wheelspin. Is this normal or do I need new tires or better throttle control? Am I supposed to let off the throttle immediately or just to reduce it a little bit? I am afraid that the bike will go sideways at some point.

Some thoughts:

1) What is the date stamp on your tires? Your tires shouldn't be older than 5-6 years from the day they came out of the factory. Motorcycle tire rubber degrades with time.
They may look just fine, but they might be too old, dry and brittle to be safe. The first thing I did when I got my 'Cat was to buy a pair without a second thought, and especially when I noticed that the tires were over six years old.
2) Check the tire pressure. Both should be close to 36, a couple more or less depending on your weight and preference.
3) Throttle control is all about being smooth. Treat the throttle more like a hot water fixture: open it too quickly, and you will scald yourself, but open it gradually and you'll know when too much is too much. Don't turn off the throttle instantly: make it quick but gradual process. As you rotate your wrist to reduce throttle, gently and progressively apply your front brake. This takes practice, since you're simultaneously controlling the throttle and the front brake. Sudden throttle releases can literally lead to momentarily locking your rear wheel or overspinning your engine, depending on the conditions. Be smooth always, whether reducing speed or accelerating.
4) Old roads sometimes look worn and porous, but oftentimes they're covered by years of oil spray and dust, and the wear itself is more like a polish. That might explain some of the spinning. Again, a smooth throttle control should keep you safe.

[SilverRider]

another thought is the rear shock is shot.

[Riceburner]

I run 36 front 42 rear. Even with worn shock, the rear shouldn't be spinning up. Sounds to me like old tire that has hardened up.

[Zafirovp]

Sorry for the long delay but we had a looong winter.

This happens way too often. As you can see I’m hardly accelerating, but still I get a wheelspin. My tyres are 3 years old - Bridgestone Battlax b022. As you can see I’m changing from 1st to 2nd gear at 5000 rpm’s with 1/4th throttle.

https://youtu.be/hRMBp-mxCY4

[Micah]

I'm not familiar with the b022, however, I am familiar with the BT-021 you referenced in the first post. The BT-021s are a sport touring tire, and a bit harder than the sport rubber available today. That said, they shouldn't spin up unless one of three things:

1. They are extremely old.
2. You've run over something slick, like the oil patches at stop lights and the tire has kicked it up.
3. You're leaking oil on to the back tire.

Did you get something slick on the back tire (chain lube, motor oil, etc.?). I watched your video, and didn't see anything abnormal in your acceleration.

Micah

[vashtsdaytona]

You're not going to spin the wheel at 5000rpm 1/4 throttle on a thundercat. You're clutch is slipping.

Start by looking up clutch adjustment here. What lol you using? If not that new clutch springs. If not that new clutch plates

[Micah]

Good call, Vash. I agree with you. Not the tire. It’s the clutch.

[Reserector]

I once had a slipping clutch on an XS650 that felt like wheelspin. It was the result of using the wrong type of oil in the case. I hanged oil to the correct type and it gradually went back to normal as the wrong oil worked its way out of the clutch. You may have the same problem.

[Jonny1977]

I recall rear wheel spinning on a damp road due to a seized front caliper.