Tubeless conversion for spoked wheels. Any thoughts?

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I recently came across this:
http://www2s.biglobe.ne.jp/~outex/tubelesskitenglishlist.htm
I am really tempted to try this on my new shoulderless Morad 2.50x18 rear wheel (Talon KTM 500 MX disc brake hub, SS spokes)
I just weighed a 4.00x18 inner tube I had, it was almost 2 LBS!! It may be a Heavy Duty offroad tube, but still stupid heavy. And most available premium tyres are tubeless anyway these days, so not ideal for use with a tube. Losing 2 Lbs of unsprung and rotating weight seems like a good deal to me, unless there is a catch somewhere.
(I do realize that my Morad rim is missing the "bead retaining bulge" that some dedicated tubeless rims have) And the tire I am using is Avon AM26 in 120/90-18.
 
It sucks that ANY rims are still being made without the retaining bulge. My 98 Honda Shadow had the bulge on it's tube type spoke rims. It may have saved my life when I blew a rear tube on the freeway at 70MPH ( my fault, tire wore though where it had been flat spotted). Tire REALLY flopped around but stayed on the rim........
 
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The Japanese vendor of this conversion kit claims that sudden loss of pressure is less likely when running tubeless, compared to running a tube. Whether the rim has "Retaining bulge" or not.
I once had a front tube blow out on my RD350, when I hit a fist sized rock on an unlit country road. Instant flat, luckily I stayed on the road.....So inner tubes are not really safe either.....
 
It do appreciate your input on this. But do all oem cast wheels marked "tubeless" actually have this "bead retaining bulge"? Or is it a more recent feature? I guess tubeless became more common in the 80s..
 
Look on other sites. The supermoto guys use this kit or the DIY version a lot for faster tire changes. ADV guys do it for easier flat repair in the middle of nowhere. Lots of people love it, lots of people hate it. It does seem like the newer the rim it is done to the easier the install and less likely to leak as there is no corrosion. But to really get a feel check sites like supermotojunkie or advrider, big threads on both.
 
Ya wanna go tubeless.....wrap a few thousand rubberbands around the rim! THAT will work!
I give the fuck up!

And I'll pass along to a few friends, that have collectively spent decades working for Dunlop, Yokohama (yes, back that far) Metzler, Pirelli and the ones I worked with at Dunlop, that none of them know their ass from a hole in the ground about tires and rims.
I totally respect your view on this subject. But few things are black or white in this world. Inner tubes do work, but still have their drawbacks.
 
Just because something could be done, it isn't necessarily a good idea and should be done.

And so, I have to agree with Solo2Racer on this. I can tell you that from my professional life, there are few technical topics in the motor vehicle industry that are more carefully engineered than wheels and tires and so if something is not recommended...then DON'T is a good rule of thumb.

The other issue I see is - how the heck do you reliably seal all of those holes in a spoked rim? I can imagine that keeping air in that wheel would be a constant, 24/7 "trip to the dentist".

If loosing two pounds is really that vital, I'd suggest skipping a few lunches.

Pete
 
Pete, thanks for your input, much appreciated!
One issue I haven't mentioned is inner tube in a tubeless tire. That is not really recommended either, but tube type tires Are not always easy to find. Sort of a dilemma
 
Pete, thanks for your input, much appreciated!
One issue I haven't mentioned is inner tube in a tubeless tire. That is not really recommended either, but tube type tires Are not always easy to find. Sort of a dilemma

Now THAT is very true ArcticXS - but I think an inner tube in a tubeless tire is something that has been considered by the tire industry in essentially ceasing to make tube-type tires and so I am not worried about it.
 
I agree with Pete. I think tubeless tires are designed to be run either way. I've been putting tubes in them for many years and never had any issues. I also have or have had tubeless tire wheels on some of my bikes. Honestly, I can't say I see any big difference in performance between the two types. Granted, changing is easier when you don't have to deal with a tube but I've changed so many tube type over the years that it's no big deal for me anymore.
 
Yamaha was late to the game, they had tubeless rims that do NOT have the bead. There's a thread with pics in here somewhere.

Yes. Tubeless started to be the thing in the 1980's with more and more cast wheels. That's NOT to say that all cast wheels are tubeless. Early wheels would be marked "Tubeless Tire Applicable" and should have the "bead retaining bulge" . Obviously, wire spoke rims are not tubeless.

It seems Suzuki was late to the tubeless party as well. The 2 firsts pics are of the front wheel of my cousins Suzuki GR650 Tempter, which must be 83 or 84 model. No "bead retaining bulge" on that wheel. So it would be just as safe or unsafe as any other WM type rim in that respect.
IMG_20191019_194445_0.jpg
IMG_20191019_194520_7.jpg
IMG_20191019_201210_8.jpg
The last pic is my new wheel with Morad flangeless alloy rim. It appears that the radial grooves would make it impossible for a tubeless tire to seal. So inner tube it is.
 
Another factor that I see is the condition of the rim to start with. My rear wheel ('74 TX650A, aluminum spoked rim) had much more aluminum corrosion than my front wheel, corrosion in the valley of the rim where the nipples are. OK, then some lighter corrosion on the rims "bead" area. I cleaned up the valley and bead areas and painted the valley with brush-on Rustoleum. Knowing how vulnerable aluminum car rims are to the slow leaks...………..There is ABSOLUTLY no way that I would go tubeless on that rim. More sanding and smoothing to make a better seal for tubeless would have removed a lot of bead area, don't like that scenario.

Scott
 
"A tube weighs 2 pounds" Minor point; sealing the rim will add some weight also.

mrtwowheel sometimes you just need to say a wheel is too far gone to save........... They are kinda impotent.

Yep, scrap the junk. No doubt this rim is still good. If it was steel I would say that it just reached the pitting point, nowhere near the cracking and crumbling point.

Scott
 
"A tube weighs 2 pounds" Minor point; sealing the rim will add some weight also.
Of course, but hardly 2 lbs (I suspect that tube is some kind of heavy duty enduro/mx tube)
I ordered a Michelin street type inner tube, it will be interesting to see how heavy it is.
2 lbs of rotating AND unsprung weight should be noticeable anyway. Some people buy super expensive carbon fibre wheels to drop that kind of mass off their street bikes.
 
Today, my Michelin tube arrived. It weighs 675 gram, while the VeeRubber one I already had weighs 785 gram (not quite 2 Lbs)
So the difference is 110 g or around 4 oz. Not a whole lot, but at least a little bit. About the same as a gun drilled rear axle would save. At least the saved weight on the tube is rotating as well as unsprung, and on a large rotating radius.
 
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