Minimizing wheel weights -- important?

[Constant Mesh]

I just mounted a new PR2 on the front. It had no weight markings.

It balanced fine using the Parnes but I used a lot of weight. The bare wheel has an unbalance of 4-1/2 weights.

What's the benefit of using a bit less weight? I've never had a stick-on weight come off.

Is it worth the effort to identify the tire's light spot and mount it accordingly?

 

[RossKean]

The Michelins don't have a marked spot; at least not the ones I have encountered. My wheel are both a bit out of balance, although not at the valve stem. If I find that a new tire is needing more than about 1.5 oz, I will generally break the bead and rotate the tire 180°. Does it matter? I don't know. If the amount of weight is excessive, I would attribute it to a bad tire and I would have a discussion with the vendor.

 

[MCRIDER007]

If you are referring to 4.5 1/4 oz (7 gram) weights I would say the answer is "NO".

 

[Ignacio]

What's the benefit of using a bit less weight? I've never had a stick-on weight come off.
Is it worth the effort to identify the tire's light spot and mount it accordingly?

If you're Valentino Rossi you might shave a couple thousandths off your lap time.

I don't know. Is it to you?

 

[xcsp]

I agree with Ross, if it calls for a lot of weight to balance, rotate the tire on the rim.

Had a PR2 mounted on the rear wheel of my previous FJR and the shop had something like 3-4 oz of weight, seemed odd and looked like hell on the rim, took it back, rotated the tire on the rim and it only took about an ounce!

 

[Bokerfork]

My question is why does your bare rim require so much weight? That doesn't seem normal.

 

[Brodie]

I change my own - balance my own. If it balances it should be good to go.

That said, I take the time to break the bead several times to rotate the wheel within the tire to get the least amount of weight. I start out with the old weights removed and know where the heavy spot of the bare rim is. Since I am not paying anyone to do the work I can take my time. Several tires have balanced without any weights, that's my goal. Kinda like a labor of love.

If you're paying someone to do this be prepared to pay the prevailing shop rate for their time.

Brodie

 

[carlson_mn]

PR2 and PR3 are not marked. Can't speak for PR4 but I'm sure they aren't either. 15-40 grams is common. If it was more than 60 grams I'd think about rotating the tire. That's just cause it would make me feel better. With a rim and tire weight of 20-25lbs an extra 1 or 2 ounces is not going to put any noticeable effect on the suspension or efficiency (assuming it's balanced).

 

[escapefjrtist]

My question is why does your bare rim require so much weight? That doesn't seem normal.

Pretty typical of FJRs. My bare rear [rim] takes 42 grams to balance, front takes 20 grams. The heavy spot is also not at the valve stem, it's approximately 90 degrees off in both cases.

--G

 

[Fontanaman]

Like --G my FJR takes 4 to 5 (the exact number escapes me) 1/4 oz weights to balance the wheel sans the tire. I used black colored weights for the balance sans the tire. After mounting I balance it again and use silver weights usually 1/4 oz or none. Trust the balance job and be happy.

 

[Constant Mesh]

Would the following procedure work for quickly finding heavy/light spots on an unmarked tire?

Using the Parnes, etc. balance the bare wheel with temporarily attached weights. Install one bead of the new tire onto the wheel with the other bead suspended off the rim in the air. Push the installed bead all the way to the rim on the opposite side of the wheel. This should center the tire about the axle, same as when it's properly installed. Should be pretty easy to push the bead over tight against the rim. Now, find the heavy/light spot of the tire with the Parnes. Since the bare wheel is temporarily balanced you've identified the tire's heavy/light spot.

Only issue I see with this procedure is the length of the Parnes axle. It may not be long enough since most of the tire's width will be located outside the wheel, increasing the overall width. But one could just extend out a support for the Parnes on one side which would pass through the tire effectively lengthening the Parnes axle.

This should work fine since we're just doing a static balance. All you need is the tire centered about the axle. Installing one bead should accomplish that. Doesn't make any difference where the tire's located left-to-right on the axle as long as it doesn't affect the friction of the Parnes bearings.

 

[RossKean]

^^^ Maybe mount the tire but don't pressurize to seat the beads? Don't know if it would work or not. Fairly easy to rotate the tire on the rim as long as the beads aren't seated. Bead needs to be lubed.

On the other hand, maybe we are making too much fuss over this. I don't bother with it unless the tire seems pretty far out.

 

[MCRIDER007]

Would the following procedure work for quickly finding heavy/light spots on an unmarked tire?
This should work fine since we're just doing a static balance. All you need is the tire centered about the axle. Installing one bead should accomplish that. Doesn't make any difference where the tire's located left-to-right on the axle as long as it doesn't affect the friction of the Parnes bearings.

My experience is that you cannot find the light spot on the tire unless you balance the rim, install both beads, and also fully inflate the tire.

 

[Aasland]

Would the following procedure work for quickly finding heavy/light spots on an unmarked tire?
Using the Parnes, etc. balance the bare wheel with temporarily attached weights. Install one bead of the new tire onto the wheel with the other bead suspended off the rim in the air. Push the installed bead all the way to the rim on the opposite side of the wheel. This should center the tire about the axle, same as when it's properly installed. Should be pretty easy to push the bead over tight against the rim. Now, find the heavy/light spot of the tire with the Parnes. Since the bare wheel is temporarily balanced you've identified the tire's heavy/light spot.

Would the following procedure work for quickly finding heavy/light spots on an unmarked tire?
This should work fine since we're just doing a static balance. All you need is the tire centered about the axle. Installing one bead should accomplish that. Doesn't make any difference where the tire's located left-to-right on the axle as long as it doesn't affect the friction of the Parnes bearings.

My experience is that you cannot find the light spot on the tire unless you balance the rim, install both beads, and also fully inflate the tire.

Only issue I see with this procedure is the length of the Parnes axle. It may not be long enough since most of the tire's width will be located outside the wheel, increasing the overall width. But one could just extend out a support for the Parnes on one side which would pass through the tire effectively lengthening the Parnes axle.

This should work fine since we're just doing a static balance. All you need is the tire centered about the axle. Installing one bead should accomplish that. Doesn't make any difference where the tire's located left-to-right on the axle as long as it doesn't affect the friction of the Parnes bearings.

That has also been my experience. If one of the beads aren't seated, in some places the tire will be further from the axle and that will have a pendulum effect, throwing off your balance. I found this out the hard way when trying to mount/balance a tire without running the compressor (as that would wake my son), thinking I could just seat the beads and inflate the tires in the morning. I was astonished how many weights I needed and thus I re-balanced after seating the beads and the balance was totally different.

If you put an excess of tire weights on the tire it should get your attention. But 4.5 7gm weights is not excessive.