Front tire bounce?

[kleake]

I never really payed much attention previously, but after putting on my PR2's I started noticing a front end bounce at ~30mph. I didn't give it too much thought because I thought it might be the road and the way they lay the blacktop, and if it was a tire, I would notice it at many speeds. Well, as I have been racking up more miles this is getting me concerned. Has anyone else had this sort of thing happen with tires? I don't feel it under 20 or over 40, but right at 30 it gives a good bounce like motion at the speed the tire is rotating. If it was off balance I wouldn't think I would feel it until much faster, and if it was out of round or similar I would think I would feel it at higher speeds. The bike is solid all the way to 140mph (shhh, don't tell anyone) and I can't physically see any issue with the tire.

 

[Bluestreek]

Sounds like tire is out of balance

 

[03HiYoSilver]

Or a remote chance you may have a deformed/out of round PR2. Put it up on the centerstand with the Rear Wheel down and spin your front wheel and look for any oddity.

 

[Ignacio]

I'd check balance first.

But it's possible it may be out of round and a QC anomaly. My very first Avon Storm front was this freak of nature that literally would bounce an inch or two off the pavement at 25-35 mph...and become less noticeable at higher speeds. They took it off in Reno and said it balanced fine, but it hopped down the street.

Took it back and told them to put a brand new tire on it and they looked at me incredulously as it only had 1000 miles on it. The new tire was butter smooth and I told the incredulous service guy he could have the tire.

 

[C&C]

Put the front end up in the air and spin the tire; I'm thinking you have an out of round tire.

 

[kolonial72]

I have a similar condition around 40 mph. Tire is balanced and appears to be round. Hopefully the next PR2 front - if I go with them again - does not exhibit the same tendency. Oh, and it started at around 5k miles.

 

[kleake]

My very first Avon Storm front was this freak of nature that literally would bounce an inch or two off the pavement at 25-35 mph...and become less noticeable at higher speeds.

This sounds exactly like mine. I did put it up on the center stand and spin it. There is an every so slight dip in the tire as I spin it. I have about 2k miles on it since it was put on about 9-10 months ago, what should I expect for a warranty? I bought it through Cycle Gear and they installed it. Any chance they will replace it free?

 

[ionbeam]

One thing you can take a look at is the bead line on both sides of the front tire. There should be a thin raised line on the tire sidewall just above the rim of the wheel; this line should be evenly spaced all around the rim and equal on both sides. If the tire failed to seat the bead evenly around the circumference of the rim it might cause what you are seeing. It's a long shot, but it is cost effective to check.

 

[Harald]

One thing you can take a look at is the bead line on both sides of the front tire. There should be a thin raised line on the tire sidewall just above the rim of the wheel; this line should be evenly spaced all around the rim and equal on both sides. If the tire failed to seat the bead evenly around the circumference of the rim it might cause what you are seeing. It's a long shot, but it is cost effective to check.

You beat me to it with that suggestion. I've actually experienced this on a previous bike where I skimped on the tire lube when seating the bead and had incomplete seating. That front tire hopped just like the OP's. :angry2:

Of course, it's easy enough to break the bead, properly lube the tire and then reseat it. :yahoo:

 

[kleake]

I went by cycle gear and spoke with a sales person. She seemed to think if it is a mfg defect, they will take care of it, but the manager was gone to lunch so she had to refer it to him when he gets back. I'll stop by after work again to see, but I am keeping my fingers crossed, they have always done a pretty good job before on any issues I had.

I didn't think to check the bead since CG installed it, but while I was spinning it the sidewall didn't appear to move as much as the actual tread did. If they say they will take care of it, I will inspect it very close after I pull the wheel off the bike. I also have a balancer so I can spin it easily and mark the place for them.

 

[exskibum]

One thing you can take a look at is the bead line on both sides of the front tire. There should be a thin raised line on the tire sidewall just above the rim of the wheel; this line should be evenly spaced all around the rim and equal on both sides. If the tire failed to seat the bead evenly around the circumference of the rim it might cause what you are seeing. It's a long shot, but it is cost effective to check.

You beat me to it with that suggestion. I've actually experienced this on a previous bike where I skimped on the tire lube when seating the bead and had incomplete seating. That front tire hopped just like the OP's. :angry2:

Of course, it's easy enough to break the bead, properly lube the tire and then reseat it. :yahoo:

You both beat me to that observation. I've been using PR2s for the last 36K miles (I've mounted all of them), and have found the ones I've had (and the Pilot Powers I use on the Blackbird) to be very consistent and well balanced. Good luck getting it taking care of -- that isn't a symptom they should have. I love the PR2s.

 

[ionbeam]

...She seemed to think if it is a mfg defect, they will take care of it, but the manager was gone to lunch so she had to refer it to him when he gets back...

I rolled my sweet handling FJR into my garage with the front tire almost through the wear bars and the rear tire into the steel cords. In a favor a local Yamaha dealer installed my brandy new Diablo Stradas for me. I rode out of my garage on a wobbling nightmare. I told the dealer that 'in goes the good, out comes the bad'. At lunch I stopped by while the dealer (at no cost) checked my install, removed both wheels and then tested them for balance. Balance was good. Next the dealer checked the radial and lateral run-out of my rims. The back was perfect, the front rim showed a very slight bend. At no cost, my good dealer dismounted and remounted the tires and asked me to road test them for a few days. Wobble, wobble, wobble. I stopped back by the dealer for some parts when the service manager spotted me. He came flying out to tell me that (on his own initiative) he told his Pirelli tire dealer about my problem and Pirelli agreed sight unseen to replace my front tire at no cost. Bear in mind that my front tire was an internet purchase, not from this dealer. The tire swap was made and ------- perfect handling, no issues at all. In fact, after 10k miles handling was still perfect. It sticks in my mind that the Pirelli rep so quickly agreed to warranty replace my front tire. I mean there wasn't blood letting or loud, harsh words; Pirelli just stepped up -- like they perhaps knew something...

Which is a very long winded way of saying that I hope your dealer and tire manufacturer steps up for your.

 

[kleake]

Talked to the manager who was very nice. He looked at the bike and said he has never seen a PR2 bad. His thought is maybe a balance issue. I told him I think it's more than that. He said to pull the wheel and bring it in and he'll check the balance and spin them. If there is a problem, he will take care of it. He didn't specifically say replace the tire, but did emphasize he will take care of whatever the issue is. So I left feeling pretty good. He is out of this size, but has some ordered and expects them tomorrow or Thursday so my plan is to pull it and drop it by.

When I got home I checked to make sure the tire was seated all the way, in which it was. As I spin the tire, the left side isn't as bad as the right side. Basically it is worse just to the right of center, but either way it is only a slight bit out of round. Now the confusing part, I checked the back tire just to see what it looked like. To my surprise, it has a dip in it, almost like it has been locked up for a decent slide. Now I am confused? I have ABS, and I have put all of the miles on these tires and they have never slid,,, maybe spin a little, but never a slide. I also DEFINITELY feel the bounce in the front end, and it's more of a smooth bounce up and down. If the rear was causing it, it would feel more like a bump. It looks like I am going to be taking both of these down there. I'm not sure what I did to luck out and get one bad tire, but how did I end up with two!? nutts!!! :blink:

 

[kleake]

Well, the PR2's have been back ordered and it's going to be 2 weeks before they can get any in, but they have the new PR3's in stock! Woohoo!!!! I took them down, he definitely said he see's the problem with the front, and can see an issue with the rear as well, but both are minor. Two choices,,,, send the tires to Michelin and let them inspect them and they will issue replacements,,,, or since I didn't buy the road hazzard, CG will put it on there for me and I only pay for a pro-rated amount. Well, new tires come with 9/10ths of tread depth, mine have 6/10ths, so according to the warranty they would cover 58%. Well, CG is going to cover 70%! So I end up paying 30% plus the upgrade price to the PR3's or wait for the PR2's... You guessed it, I am upgrading to the PR3's... Overall, not quite as good as I was hoping, but also realizing I have used 30% of the tire, and they are doing it in store rather than getting the mfg involved which could take much longer, and they would likely argue that there isn't a problem. I am happy, CG stepped up and took care of me the best they could, and even better then what they should have according to their policy. Now, we'll see how good these PR3's are, I know they sure look nice!

 

[kleake]

I've put about 500 miles on the PR3's so far and they are smooth as silk.... I haven't pushed them hard yet, but in the moderate range they are working just as good as the PR2's did, only without the bounce. They do look a little different with the extra grooves, but that should improve wet performance. After I get a couple thousand miles on them I'll know more, but so far I am happy...

 

[Monty]

Had this happen on a cage tire awhile back. After taking it back to the tire dealer and having it rebalanced to no avail, I asked if it could be out of round. He says no such thing as an out of round tire these days as they are made by computer. I'm thinking full of shit as a Christmas turkey. After much complaining and threatening to go to an attorney, he replaced the tire. The bouncing immediately went away.