Front tire shake...

[azcycle]

As you know, I just put some new rubber on the r65 and it went fairly well.  However, there is a very noticeable front end shake around 25-30mph (estimated) that smooths out both below and above that speed. The wobble feels like I'm riding over washboarded road, a very "up and down" movement. I thought perhaps I needed to take another look at the balance of the front tire but it is well balanced.

However, when I was spinning the front tire to check balance again I did notice a "lump" or around a 3-4" stretch of tire that was higher than the rest.  The tire seems to be mounted correctly, so why this lump?  I'm sure it is what is causing the front wobble. It is not obvious just looking at the tire... but is quite so when spinning and watching the profile of the tire as it turns.

Have any of you ever experienced this?  Perhaps the tire is still not mounted correctly or maybe it is a damaged tire?

Thoughts?

[Bob_Roller]

Inner tube folded over on itself, or some other problem with the tube the way it is sitting inside the tire .

Less likely, a deformity in the tire itself .

[Lucky_Lou]

I had a similar problem on the car a rear tyre had deformed on the inner edge if the "lump" doesnt go when you deflate the tyre a replacement will be needed.
Lou

[azcycle]

I fiddled with it a bit today and noticed the lump corresponded with the valve stem. Upon closer inspection, the valve stem was slightly angled so I removed the valve core and straightened out the stem, and pumped it back up with my bicycle floor pump to 60psi, then back down to about 34psi.  Spun the tire and while there is still a *tiny* bump/wobble, it's much better. Gotta take it for a spin to be sure.

Though while inspecting everything closely, I also noticed the wheel itself is banged out of round, too. It's got a small wobble as well, from a curb or pothole hit, maybe?  I'm thinking maybe the knobby tires absorbed some of the wobble but now that I've got the street tires on there, everything is much more apparent.

We'll see... maybe I should shop around for a new front wheel.  Is a small amount of wobble okay, you think?

[montmil]

Frequently, R65 snowflakes show up on eBay. Keep a weather eye out.

Within the DFW MetroMess, there are quite a few outfits that straighten up automobile alloy rims; they haunt the car dealerships looking for work. Perhaps check with a dealership for service providers. They might true up your front rim. Usually far more economical than buying a new part.

Monte

[azcycle]

Still have a wobble/bump at the same speed, even though the physical bump in the tire seems to be lessened (though still there). I removed the wheel last night and am taking it to a local shop for them to figure out.

[Bob_Roller]

What brand of tire is it ?

[Rob Valdez 79 R65]

What brand of tire is it ?

"Shinko 712s on sale"

http://www.bmwr65.org/cgi-bin/yabb2/YaBB.pl?num=1280883481

I've never had a Shinko brand tire.

[Bob_Roller]

Just wondering, as I'm having a Metzeler Lasertec tire installed on the front wheel of my '81 today .

[Rob Valdez 79 R65]

I will continue to buy Bridgestone Spitfires for as long as they make them.

Providing I ever ride again, of course.

[azcycle]

A small update: Took it to the local neighborhood moto shop (directly across the street from Iron Horse BMW) for a look-see. At first spin on the balance rig, the mechanic said the rim was fine and the tire looked fine, but it was WAY out of balance and the bearings were rough.  Guess my ghetto balancing wasn't that good, eh?

Of course, they didn't stock the correct sized bearings, so I ran across the street (literally) to Iron Horse, and bought new front wheel bearings. After picking my jaw up off the floor from paying $84 for the bearings, (they didn't even have the seals in stock) I delivered them and left the mechanic to do his thing.

I don't have any experience with other tires other than the previous Kendas (which I grew to dislike) so I can't compare the Shinkos, but I've put about 200 miles on these so far. They feel confident, good grip, comfortable, don't track all over the road's cracks, etc.  We'll see how long they last but I needed tires and with my pre-wedding budget they were too hard to pass up.

[montmil]

Just a thought that I should have added before now...

I found upon mounting my Spitfire on the front rim,with tube - rear runs tubeless, that removing the valve stem nut inside the rim allowed for a better valve stem install.

Monte

[MrRiden]

AZCYCLE,
Yow! $84 for bearings. Next time you are in need of bearings hit Tucson Bearing-Belt & Chain. You can get any bearing you need there at a much better price. Yea I know it's south Tucson but you can also swing by El Guero Canelo for a tasty Sonoran Hot Dog. I'll be passing through on Wednesday on the way to Bizbee but I'll be sure to make a dog stop.
rich

http://maps.google.com/maps/place?hl=en&um=1&ie=UTF-8&q=tucson+bearing&fb=1&gl=us&hq=bearing&hnear=Tucson,+AZ&cid=17417229871034511884

http://tucsoncitizen.com/tucsontales/2009/12/10/tucsons-sonoran-hot-dog-like-a-chili-dog-on-steroids-wrecipe/

[Rob Valdez 79 R65]

I'm glad you were able to find the balance problem.

And I hope your mechanic is experienced in pre-loading BMW wheel bearings.

Here is Duane's page on the subject: http://w6rec.com/duane/bmw/wheel_bearing/index.htm

And Snowbum's page: http://bmwmotorcycletech.info/overview.htm

[azcycle]

No idea if the mechanic knows anything about BMW bearing and pre-load. My guess would be "no" so what do I do?  Call the shop and explain preload?  How long would these bearings and the hub last if preload was not properly set?