Front End Wobble - 2004 Ultra

[dcfatboy]

About 1500 miles or so ago I had my forks serviced by a Custom Builder shop.

When I got the bike back, I noticed that my tires didn't track will in a grooved patch of road. I attributed it to new tires (Metzlers). Three days ago, I go a front end wobble from stoplight to about 30 mph. I did the fall away test and my front tire went right and then stopped at center. I added grease and adjusted fall away to right, left, partial right and stop.

Now I get a little wobble around 20 -30 mph. My question is will the bearings get to the point where the wobble will go away, or do I need to replace them? (I do not want to if I do not have to.)

BTW, I was riding on the interstate yesterday at about 75 mph and the rear end started to wobble noticeably. I said to myself - well I guess I do need to change the bearings. Turned out to be a rear flat tire. I rode for about a half a mile after the initial wobble at around 50 mph. I pulled over when I smelled rubber burning.

As the tow truck driver said - stuff happens. There was about a 3 inch slice in my rear tire. My compressor and tire repair kit were of no help.

 

[ultrat]

glad your safe... thats 1 thing i worry about flat tires;

 

[glider]

It seems lately that the tires are to blame for most of the bike wobbles experienced by riders more-so than the front end problems.

Many of the popular brands have had problems and have been replaced to cure a bad wobble so you're not the first and I doubt you'll be the last either.

 

[dcfatboy]

Thanks UltraT and Glider.

UltraT, I had a passenger and she said she heard a pop and the rubber burning right away. The wobble was not uncontrollable, but I did not want to ride on the intersate at 50 mph.

Glider, do you think I will need new steering stem bearings because the bearings were adjusted too tight for so long (almost 4 months and actually probbaly closer to 2500 miles)?

Thanks

 

[Hoople]

You were riding 2 up at 75 mph, heard a pop and the tire went flat with burning rubber, and your here today like nothing happened.
Your one lucky man.

Please, You have to tell me more. What brand of tire did you have on the rear. Would you happen to know the load rating letter it was & would you know what your cold tire pressure was. Anything else like % of remaining thread & age of tire would be great to know.

 

[dcfatboy]

Hoople,

I will take some pics and get you more info.

Off the top of my head, the tire is a Metzler Marathon 880. I last checked the tire pressure 24 Jun, before my trip to Bristol, VA. I adjusted the tire pressure to 40 psi cold. I also adjusted my shocks to 35 psi. The tires (front and rear) have about 2500 miles on them.

The wobble was easily within the center third of the lane, but I was riding the bike - not sure what it looked like to others.

The tire stayed on the rim and looks fine, except for the slit and the flat.

_________________________________________________________________


The worst part was the hour wait for the tow. Funny thing is that the tow truck driver was the same one who towed me last time. Even remembered where I lived. He told me the first time that I was the only customer who er helped him with their bike. I was also the first to use his Condor Cycle Loader. Nice guy.

 

[Hoople]

Hoople,

I will take some pics and get you more info.

Off the top of my head, the tire is a Metzler Marathon 880. I last checked the tire pressure 24 Jun, before my trip to Bristol, VA. I adjusted the tire pressure to 40 psi cold. I also adjusted my shocks to 35 psi. The tires (front and rear) have about 2500 miles on them.

The wobble was easily within the center third of the lane, but I was riding the bike - not sure what it looked like to others.

The tire stayed on the rim and looks fine, except for the slit and the flat.

Wow, I just installed a set of Metzler Marathon 880 tires on both front and rear of my bike.
2500 miles on them is nothing. 40 psi cold is probably a little lower than what Metzler recommends but it can't be by much.

I wish I knew what went wrong & what caused it to go. This is the second time I have heard of the 880's doing this. I am not getting a good feeling about these tires.

I really appreciate any information coming from your 1st hand experience.
Certainly glad you & your 2up are Ok.

Dcfatboy, See if you can come up with the load rating number that is on the tire that blew..

Example: My rear tire is a 160/70 B 17 M/C 79V.

The 79 is my load rating number. The same size tire comes in 2 different load ratings.

Also would you happen to know what your combined 2up weight was. Also did it happen to be an exceptionally hot day on the Super Slab.

Thanks for any info.

 

[dcfatboy]

Hoople,

I will get load rating and tire size from tire this evening.

2 up weight probably around 420 lbs and maybe another 20 lbs max in tourpak and saddle bags.

It was hot - about 93 and muggy in the Washington DC area around 6pm. Concrete Super Slab (MM 50.6 Eastbound on Rte 66).

Hoople,

130/90 B 16 M/C 73H

 

[NEWHD74FAN]

It seems lately that the tires are to blame for most of the bike wobbles experienced by riders more-so than the front end problems.

Many of the popular brands have had problems and have been replaced to cure a bad wobble so you're not the first and I doubt you'll be the last either.

Actually, I don't know if it is just me, but lately new tires that I have been getting seem to use more weights to compensate unbalance than before. Happened the same way on previous 2 motorcycles I have been changing tires on. Maybe they are allowing more manufacturing tolerance than before...hoping that more accurate assembly techniques of the inner plies/design technology would compensate. :newsmile079:

 

[Hoople]

Dcfatboy,
Thanks for the info. Well the 73 equals a load capacity of 805#'s. According to Metzeler, the minimum & Maximum cold pressure for that tire is 44/50.

Could this be possible.
I have no idea what your FLHTCUI weighs in at. My guess would be 850? Having something like 65% 35% rear to front weight distribution would equal maybe 550# rear & 297# front.
I see the 2up payload as being 85% rear and 15% front or 374# on rear.

That would give you a "best case" static weight of 924#'s on rear.
Factor in some thrust shift of weight and you have to be near 1000#'s under dynamic conditions. (? maybe)
Factor in at least 4psi of tire pressure for some extra heat.

What do you think. Is it possible these numbers could explain why it happened.?