1978 XS1100 Tubless

[TopCatGr58]

Does anybody have a rim from a 78 that requires a tube, with the tire OFF along with any other year that is Tubeless, that can take some inline digi-photo-shots of the rim showing the appearance of the bead angles, the length of the flat edge going from the bottom of the bead edge in towards the center of the rim, as well as the tube "well" vs. the tubeless "well"??

I remember vaguely when I put a new front tire on, and also having changed my rear tire myself once, that there is a decent amount of that flat section against the bead, which makes the tire bead more secure and very hard to break "ala" the tire bead indian dance, and so I am thinking that this flat area is what is more critical in keeping the tire bead intact during a catastrophic blowout which might allow you to control it to a coasting stop!?

I would think a few degrees angle of the side/bead portion of the rim would not be as much of a concern, cause I know how hard it was to stretch/pull the tire over that diameter of the rim, so having the tire actually jump over/off/past that is highly unlikely! The opposing edge of the tire had to be deep within that center groove/well to allow enough slack in the length of the tire's bead to get it to fit over/past the rim edge.

So....it seems to me that if that flat section is just about as wide, as well as the same in actual circumference to a tubeless tire, then that the tube rim should be as safe and adequate in holding the tire on/against the bead once it's actually been mounted and stretched outwards against the side bead edge, no matter how deep the center groove/well is!?

Just trying to approach this question with some logic!? T.C.

[Winterhawk]

Thanks TopCat, I can relax a little now while riding it I hope. All I know is that it's been holding 36psi for 3 days now and seems to work extremly well with the new Metzler on it. I'll hold off on having Braden do the front tire till you guys on here decide to do or not to do. I'll get a pic of it in a couple of days when I paint the Meir fairing I put on and pinstrip it.

[Pat Kelly]

I think I have two bare rims, one "tube-type" off my E and a "tubeless" off a special (wanna buy it?). I'll take some pics and Email them to you.

[Winterhawk]

Was out at Merriam Cycle today and compared a 1979 Special rear rim to mine. Exactly the same rim. It even had the places for the 2 rim locks and it wasn't drilled out. Braden said the backs are the same, but he thinks that the front wheels are different. I still have a tube in the front untill everybody decides yes or no.

[Geezer]

Originally posted by Winterhawk
... and compared a 1979 Special rear rim to mine. Exactly the same rim. It even had the places for the 2 rim locks and it wasn't drilled out.

The 16" rear wheel also has the undrilled places for rimlocks and they were all tubless.

I know for certain the 19" fronts are different from tubeless to tube type but I've never had a 17" tubeless to compair.

Geezer

[randy]

If the rims are truly the same, then why won't a tubeless tire seat and seal it's bead on my 79F tube-type rims? I am running tubless tires with tubes installed. When i deflate, the beads release BY HAND WITHOUT TOOLS! from the rim. They do fully seat when inflated to 40 PSI, but I would never trust the tube-type rims to hold a seal on the tire bead.

Randy

[Winterhawk]

You have a point there Randy. I noticed it didn't make a popping noise when inflating to pop the bead out either.