While know it is not recommended but due to funding I have to. My question is when flipping a power cup B compound do I need to re balance it? If place a mark on the tire and rim and line them back up perfectly will this be close enough? Thanks
I would think so. Even if you line up the mark, the tire is flipped so the only part to line up with its original position is the spot opposite your mark halfway around the rim.
I thought that every time the tire came off the rim you should re balance it. At the very least you could mount the tire and spin it to see if it balances close. I tried doing this before on Dunlops and I could never line the tire up exactly opposite so I had to take/add weights.
I haven't used power cups yet but all the previous ones Ive used never required much weight and rarely (if ever) needed to be rebalanced when flipped.
The last year I raced my 1000 heavily, I zero balanced all 4 sets of wheels at the beginning of the season, mounted up about a million sets of my michelins and I think I noticed 1 giving me the tiniest sense of being out of balance. Do I recommend this to customers, or others who I am working for, no. But it's an example of the tolerance allowed. So yes, marking the rim and flipping will be perfectly ok. It's physics yo.
I do the same thing. Balanced all the rims just by themselves. I don't bother with balancing the tires. I have also had one or two give a hint of a vibration, but nothing big whatsoever. Saves a lot of time mounting/flipping tires.
How does one go about balancing a wheel? Are you guys just balancing the wheel on the outside or are you balancing the wheel internally?
It's just a zero balance. Balance the rim like any other time, except maybe put the weight a little more central and use metal tape. Modern race tires, especially the michelins are extremely well balanced. You may notice your race wheels are always getting weights in about the same place. That's because you are only balancing the wheel, the tire is damn close every time.
Didnt at Jennings last year for our private day. Didn't realize the tire shop would be closed and ended up having to flip it at lunch. No issues.
Just like the tire guys at the track/shop do. Put the wheel/tire on a stand, give a slight rotation and let it stop. Heavy spot will be BDC so mark and temporarily weight TDC and rotate again. Add or subtract weight as needed and test again. Get close (wheel pretty much stays at 90 degrees out from TDC) and stick the weight good. Pretty soon you're a pro. I used to sweat perfection until I saw that most tire guys don't, and it works fine.
By all means, if you're gridding up for Moto2 at COTA, simon, and balancing your own wheels, seek perfection.
How common is it for wheels to be out of balance? IMO wheels should be perfectly balanced before they ever reach us. Seems to me like balance should be part of the QC checks when the wheel is manufactured. Especially if they are aftermarket. I would be mad as hell if I paid $4k for a set of lighter wheels then had to add weight to balance them.