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Message |
Sean Welsh (Sean)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 12:41 pm: | |
I am looking for anyone who has used the EQUAL brand of dry-polymer tire balancing compound manufactured by IMI products (here's their web site), or any similar product.
Please share your experience here. I am asking because we have been using the product for about a year now, and have put 20,000 miles on brand new tires with it. We're having some issues, and trying to nail down whether the EQUAL is helping or hurting.
Immediately after installing the new tires, which were also mounted on new rims, we took the coach in for an alignment. The alignment was pretty much spot-on anyway, but they checked and adjusted everything on both the front and tag axles.
I don't think we really noticed any ride problems in the first 10,000 miles or so, but it is hard to say now whether we had no problems, or just did not notice them. The ride of the new tires and wheels was such a vast improvement over the old, mismatched tires we had before that everything seemed like a big improvement, and vibration and noise had, expectedly, increased somewhat due to our choice of agressive block-tread traction tires for the drivers.
In any case, over time, we became aware of a front-end shimmy, which feels quite pronounced at very low speeds, say up to about 15mph, then lessens and completely disappears at highway speeds. On certain road surfaces, we are vaugely aware of a thumping at intermediate speeds.
Inspecting the front and tag tires revealed an irregular wear pattern at the outside shoulder. There seems to be a single spot of excessive wear, and this spot was very pronounced on the left front tire, with a smaller spot on the left tag.
At 20,000, we rotated the tires in an X pattern. We also had what had been the left front dismounted to inspect the EQUAL to make sure it had not clumped or hardened into some kind of solid mass that might be throwing the wheel off-balance (it had not).
Shortly after that, I had the hubs inspected at a bus shop, and also the tag steering dampers replaced (one had a slight crimp in it, but, it turned out, is was not impinging on its travel and it still had a good bit of pressure in it). The hubs were fine: good and tight with no play (as they should be for a coach with only 70,000 miles total).
While at the bus shop, which runs a fleet of Neoplans (US-built Cityliners), the head mechanic told me that they had to pull the EQUAL from a few of their coaches because it was causing, you guessed it, low-speed shimmy. Nevertheless, they had cartons of it in the shop, and were clearly still using it in something, possibly their fleet of schoolies as they were also a school contractor.
Now we are wondering if we should remove our EQUAL and have the wheels dynamically balanced by more conventional means with fixed weights. Before I spring the big bucks it will require to dismount all eight wheels, remove the powder, remount the wheels, and have the assemblies dynamically balanced on-coach, I'd like to get some sense from others with experience if this will cure the problem. I don't want to go through all this and find my shimmy still there.
So anyone out there using dry polymer (or, for that matter, golf balls or antifreeze), please post something and let us know how it's working for you.
(For the record: I am already aware of commercial devices using either mercury or steel balls that claim to provide dynamic balance. We have looked at these products and rejected them for various reasons which are not relevant here. If we don't use dry polymer or something similar, we will be going to on-wheel dynamic balancing, which means, of course, re-balancing every time we rotate the tires.)
Thanks!
-Sean
http://OurOdyssey.US |
RJ Long (Rjlong)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 12:59 pm: | |
Sean - check your private email. . .
RJ |
David Dulmage (Daved)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 1:22 pm: | |
I used Equal in a Winnebago Chieftain motorhome; tires ran smooth, never had a problem with it.
Dave Dulmage |
Richard Bowyer (Drivingmisslazy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 2:15 pm: | |
Sean, I do not understand why you would have to re-balance every time you rotate the tires. Can you please explain?
Richard |
Sean Welsh (Sean)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 2:34 pm: | |
Richard,
When using the on-the-axle method of balancing, the weights are placed to compensate for the total dynamic balance of the entire assembly -- not just the tire and wheel, but also the brake drum, hub, lug nuts, etc.. In short, this method balances everything that's rotating, not just the tire/wheel assembly. It yields a better balance than the off-the-coach spin-balance method. However, any time the wheel is moved to a different position, the whole shebang needs to be re-balanced. (Actually, it needs to be rebalanced even if a wheel is removed, then put back on the same hub but rotated one way or the other, so any wheel removal for, e.g. brake inspection, you need to mark the stud closest to the valve stem, or other marking method, to ensure the wheel is put back exactly the way it came off.)
We could probably get by with off-the-coach spin balancing, but one reason why we went with the EQUAL in the first place was to compensate for any out-of-balance conditions in the hubs and drums.
-Sean |
Richard Bowyer (Drivingmisslazy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 4:01 pm: | |
OK, now I understand. I did now know anybody still used spin balancing. Especially on these large tires and wheels. It is my belief that a lot of people never even balance the duals, although I did balance mine.
Richard |
Jerry Liebler (Jerry_liebler)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 5:21 pm: | |
Sean,
I had a very similar dissapointment with 'Equal'. I had just replaced the front shocks When I bought new stear tires from Camping World they installed Equal (they had no other way of balancing 12r22.5s). Driving home, the bus shook noticeably on the right front side at various speeds between 20 and 50. I complained and the manager offered to pay the bill if I chose to have the Equal removed and got a conventional balance but they couldn't do it. I went to Less Swab in Hillsboro Or. , had them remove the Equal and spin balanse my front wheels. It worked, smooth ride afterward, no more shakes at any speed. True to their word Camping World payed the $140 bill.
Regards
Jerry 4107 1120 |
Jon W.
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 8:59 pm: | |
I started using Equal around 1995. I had considerable success with it because prior to using it I had difficulty with balance being maintained when using weights. It was especially a problem on the tag axle.
The tires were usually worn by about 75,000 to 80,000 miles despite fanatical attention to tire pressures based on weight.
The only set I wore out was with Equal and they lasted for 130,000 miles and the scalloping that was evident previously never appeared on the tires when I was using Equal. |
Bill Gerrie
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, February 22, 2006 - 10:34 pm: | |
Sean
I used a balancing compound about 7 years ago and after I attended a Michelin tire seminar I was told that the compound would slowly destroy the thin inner membrain in the tire that stops the tire from leaking air. Michelin wouldn't warranty any tire that was found to have a balancing compound in it. You mentioned that you don't for various reasons like the balancing rings but I put Centra-Matics on all postions and in 7 years I have no noticable wear at all on any tires. They do make a noise till you get over about 10mph but you get used to it. Bill |
Tom Caffrey (Pvcces)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, February 23, 2006 - 12:37 am: | |
Sean, we run 6 golf balls in each of our tires. We get a little shake after picking up speed from 60 to 70 mph, and then it gradually dimishes. There's a little bit left, even after running at that speed for a while.
Our tires were already cupped from an out-of-balance condition when we went to the golf balls. We did this because we were getting a pretty persistent shaking around 70 mph. It might be from an unbalanced drum; we haven't checked these, yet.
Since we went to the golf balls, the behavior of the coach has been unchanged; we never hear the golf balls.
George Lowry used both equal and centramatics, if memory serves me. The last email address I have for him is wwemu@cwnet.com, but I think that's stale.
Good luck with your tires, and let us know what fixes your problem, if you would.
Thanks.
Tom Caffrey PD4106-2576
Suncatcher
Ketchikan, Alaska |
Sean Welsh (Sean)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, February 23, 2006 - 1:43 am: | |
Hmm. Well, it looks like (including the two private responses that I got off-line) folks are split almost evenly on this issue. About half of you said it helped your situation, and about half had problems with it.
I'm going to wait a bit and see if some more folks weigh in.
For the record, we can't use Centra-Matics (or the similar TAABS) because they do not make a product that will fit our wheels.
Sun-Tech (Balance Masters) makes a 335mm product, but I am philosophically opposed to using mercury for this application (and, frankly, would like to see Sun-Tech discontinue this practice altogether).
Conceivably, we can use golf balls. Liquid media is out because it will cause problems with the sensors for our SmarTire system, which are inside the wheels.
Thanks for all your feedback.
-Sean |
niles steckbauer (Niles500)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, February 23, 2006 - 3:08 am: | |
Sean - I have always been told that radials (I'm assuming that's what you use) should never be rotated in an 'X' pattern, and only front to rear with same directional rotation - HTH - Niles |
Sean Welsh (Sean)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, February 23, 2006 - 8:53 am: | |
Niles,
That particular piece of wisdom is out of date.
Many years ago, in the early decades of radial tire development, there were potential issues with tread separation if the rotational direction was changed. For this reasond the advice was to rotate only on the same side, which made it simple since no dismounting/remounting was required. Of course, if you used different types of tires on the steer and drive axles (for example, snow tires only on the drive axle), you still had to rotate side-to-side, and, in this case, you needed to dismount the tire and flip it around on the wheel, in order to preserve the direction of rotation.
Radial tire development has come a long way in 30+ years. With today's radials, the only reason to preserve rotational direction is if the tire has a directional tread pattern to begin with. (Some high-end automotive tires have directional patterns; almost no coach tires do.)
I supposed it is possible that there are still manufacturers who make this recommendation, either for all their radials or for specific models. However, the manufacturer's recommendations for my Bridgestones, which go into great detail about tire care, inflation pressures, operating speeds, etc., make no recommendation against rotating them side-to-side.
In my case, unless I want to dismount/remount, I have no choice but to swap sides -- I use different tires on my drivers than I do on the four steerable wheels. Moreover, I use different wheels on the inners and outers (I can't dual aluminums on my pilots), which means that I have to swap the drivers left-for-right and vice-versa to rotate them at all.
While, conceivably, I could stick with front-to-back same-side-only rotation on the steers and tags, it means that the tire layout graphic on the SmarTire will be caddy-whumpus, or I will have to reprogram all eight sensors (a real pain-in-the-a$$). By using this rotation, I just look at the little bus in the graphic as moving from left to right instead of from right to left, and the sensors retain their original numbering.
-Sean
http://OurOdyssey.US |
Sean Welsh (Sean)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, February 23, 2006 - 8:58 am: | |
Follow-up:
Niles -- here is a link to the actual recommendation from Bridgestone for *all* their radial truck tires:
http://www.trucktires.com/us_eng/technical/bftechnical/tire_rotation_b.asp
-Sean |
Gary Carter
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, February 23, 2006 - 1:19 pm: | |
I have used Equal since the early 90s and would not be without it. I do not do any other balancing. I have also used anti-freeze in a car and a friend uses it in all of his truck trailers.
As to the cupping it sounds like you may have Goodyear tires. They are know for that on the steer and tag axles or least they were. I used to be a Goodyear fan and went thru two sets on the front of our 4106. Finally put on Kumhos (cheapest tire I could find) and never again had the cupping problem. In fact when getting ready to buy the third set of tires in six years, more than one dealer upon hearing of the cupping asked if I had Goodyear tires. |
Tom Caffrey (Pvcces)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, February 24, 2006 - 12:26 am: | |
Gary, it was Goodyears that cupped on us. Maybe, that's all we're struggling with.
I'll try to remember the Kumhos when we re-tire.
Tom Caffrey PD4106-2576
Suncatcher
Ketchikan, Alaska |
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