Five grooves across aluminum rims, bead lube

Single & twin cylinder model BMW Airhead specific discussions
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Curt
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Joined: Fri Aug 13, 2010 1:47 pm

Five grooves across aluminum rims, bead lube

Post by Curt » Tue Aug 12, 2014 10:13 am

Looking from the tube's point of view, the circa 1962 aluminum rim has five ridges within slightly less than half the rim's circumference. As these might somewhat affect how the tire beads fall into the drop center during mounting, is there any recommendation on where to begin the tire removal or installation process? Why are the ridges there?

Is there a recommended bead lube for mounting? Will silicone cause the tire to slip around the rim and damage the tube's valve stem?

(edit: just read Duanne's site on this--http://www.w6rec.com/duane/bmw/5dents/index.htm

( Duanne left mounting for future subjects, so main question now becomes where on the rim to start mounting, when to insert tube into tire, and when to pull stem into rim. Think I'll look at owners and shop manuals.)

Major Softie
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Re: Five grooves across aluminum rims, bead lube

Post by Major Softie » Tue Aug 12, 2014 1:34 pm

Afraid I had steel on my /2, so I'm not familiar with these rims.
MS - out

Kurt in S.A.
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Re: Five grooves across aluminum rims, bead lube

Post by Kurt in S.A. » Tue Aug 12, 2014 9:26 pm

My understanding is that the 5-dents were there to help prevent the tire from becoming dismounted during a severe deflation. The dents prevented the tire bead from dropping so far down in the rim center. So, if you're going to mount a tire, you would want to drop the tire bead into the center of the rim opposite of the dents...this provides the most room to work with when working the rest of the bead across the rim.

Kurt in S.A.
Last edited by Kurt in S.A. on Wed Aug 13, 2014 9:12 pm, edited 1 time in total.

Duane Ausherman
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Re: Five grooves across aluminum rims, bead lube

Post by Duane Ausherman » Wed Aug 13, 2014 11:21 am

+1 for Kurt, I must go back and check my article when I get some time. I can't believe that I didn't cover this issue. There is no mystery of the 5 dents in any respect. The owners manual covers it too.

All /2 rims had the 5 dents, not just the alloy ones.
Last edited by Duane Ausherman on Sat Aug 16, 2014 2:48 am, edited 1 time in total.
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Curt
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Re: Five grooves across aluminum rims, bead lube

Post by Curt » Thu Aug 14, 2014 3:24 pm

Should have said in my edit that Duane covered the dents (by blue word link) in his excellent, with photos, dismounting instructions...which I read after dismounting one.

Duane Ausherman
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Re: Five grooves across aluminum rims, bead lube

Post by Duane Ausherman » Sat Aug 16, 2014 2:55 pm

Curt wrote:Should have said in my edit that Duane covered the dents (by blue word link) in his excellent, with photos, dismounting instructions...which I read after dismounting one.
Curt, thanks for the kind words on my tire article. I really do want to finish it with the mounting procedure described in detail. I recently mounted two tires, but it was on Honda wheels. I use Honda wheels for my home made garden cart. The rubber quality is poor, as I had to replace them after only 35 years of sitting outside in the shade.

I appreciate that you first dismounted your tire from the wheel in order to be qualified to then critique my article. Too many do it the other way around and then I don't get any feedback.

However, you violated Boxerworks cultural standards. You are supposed to ask here how to do it and expect us to type it all over again. I like typing so much that I appreciate that people give me a reason to retype it again and again.
Ask the Indians what happens when you don't control immigration.

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