I agree...adventure motorcycling was borne out of the necessity to bodge and experiment...in fact, that's how a lot of proper solutions got developed and sold, and subsequently integrated into later models of that bike/product.

I am a huge fan of tubeless. BUT aside from the rim, tire choice is extremely important and complicated. Beyond the tread pattern of the TKC vs the Anakee, etc. You have to consider the sidewall strength, the composition of the plies, and number of the plies on both the sidewall and tread.

I luckily suffered only one puncture on my last trip, plugged it. There were quite a few sharp rocks in the Niger and Algeria that promised to shred my tire, but luck and a 5 ply tread on rear and front, supported by 5 ply tread on the sidewalls, absorbed the blows readily.

__________________
edde
93 BMW K75s
www.motoedde.com

edde- what 5x5 tire were you running? Hope to talk to you before I return to Africa, am "doing" the west coast route this time before re-visiting the east coast. Later, H.

__________________
"And I think to myself, what a wonderful world..." L.B. Armstrong. www.davesgreatescape.net
http://www.facebook.com/inbox/readme...e&id=661274218

I've had good and bad experiences with both slime and ultraseal. The issue seems to be a mixture of cure time and hole size. If the hole is small a small number of rubber bits block it, it cures quickly and you have a near permanant fix. If you get a big hole you get the "tea leaves in the sink" effect and get to do a proper fix after your next meal break. If you get a hole in a surface that moves or isn't flat (seam of a tube in my case) it simply doesn't work and the stuff is just messy. All in all though I can see practical advantages to this. I don't carry it as the Bonneville has very easy to change tubes, but for example with my dad's Guzzi running tubeless tyres on the worlds tightest tube type rims, Ultraseal would for sure be my first choice if he ever went more than a hundred miles from home.

Like I said, it's the engineer in me that likes to see proper testing, an affliction that no doubt does prevent progress that inventive people will naturally bypass. I've had one explosive blow out in my previous test driving career (I used to work for WABCO the brakes people), fortunately on an axle with twin tyres but the noise was enough. I can also change my tubes in next to no time, so no encouragment there I guess

The comments from the guys doing this in the US are interesting. The bigger the wheel the harder it is to seal, or is it the front position? The spoke flexing is different either way IMHO. A rear is going to flex it's spokes based mostly on engine torque applied? The ends of the spokes to me will "roll" in the rim, something the front also see's under braking? The front is subject more to impact type hits to the rim trying to push the spoke into the rim, making a gap a little like a poppet valve as the rim flexes? The longer the spoke the bigger the gap created when it moves, so the harder it is to keep your chosen seal in compression?

As a test routine, I'd want to seal the biggest rear I could and ride it off road so it see's impacts. Then I'd want to try the same size as a front, so 19-inch on a classic/Enfield? You'd at least be learning if it's the wheel loading or spoke length that limits your seal. Hopefully you find out if you've got a rolling or opening issue and can then add a suitable o-ring or flat seal to support the semi-liquid?

My other fear is changing the resonant frequency of the wheel by some stiffening of the rim to spoke joint. What's the chance of breaking a spoke now and after the seal starts acting as a damper? If a spoke breaks what are the chances of this causing a rapid tyre failure? Like I say, it's just the engineer in me that likes to see FMEA's and the like on safety critical items.

Good luck to the innovators out there

Andy

All good points Andy that make theoretical sense to me. You do wonder why matey has recoded front 21s failing - could be less tyre mass to absorb impacts (compared to a chunkier rear) and longer spokes like you say. But the only spokes I've ever broken were on the rear which takes much more load in an overland rather than racing scenario.

I do wonder about the loss of spoke-tensioning/repairing ability with the 3M method. May be fine on some fat highway cruiser but we're all about crap roads in poor countries and off roading with big loads. For years I always fitted my bikes with HD spokes on decent rims (if necessary) but on the last trip a custom HD re-spoke made things worse on mine (the other bikes - same models & load - had no breakages).

This is why for real world overlanding I think I might prefer the Tubliss liners - they are easy to reverse.

Ch

__________________
Adventure Motorcycling Handbook 8 • Morocco Overland 3 • Overlanders Handbook 2 • Twit

So Chris,
Have you done it yet? I am so curious it is killing me!! (wow i am such a child )

__________________
2000 Africa Twin
http://two-up-ona-twin.blogspot.com

Hi Xander, just got back and getting round to a Maroc trip soon. My bike is 21/17 so may run a Tubliss in the front and glue up the rear (which I plan to convert to 18 later anyway).

What could possibly go wrong?

Ch

Later: no Tubliss cores in any useful size in the UK yet so will go for the much cheaper 3M option

__________________
Adventure Motorcycling Handbook 8 • Morocco Overland 3 • Overlanders Handbook 2 • Twit

why bother? theres nothing stopping you putting a tubeless tyre on a spoked wheel with a tube inside. i have sports tyres on my XT600E and they work just fine with tubes inside.

__________________
dave

I'm not sure you get it Davsoto. It's not about tyre choice or radials, it's about running tubeless tyres without tubes because tubeless is widely considered to be better.

Ch

__________________
Adventure Motorcycling Handbook 8 • Morocco Overland 3 • Overlanders Handbook 2 • Twit

dont see why chris, but whatever floats your boat........

__________________
dave

because the tubeless tyre (with no tube in it) runs cooler, so should last longer. also it should not deflate so quickly when it punctures.

THIS is the point of Tube less.

As noted,

__________________
Patrick passed Dec 2018. RIP Patrick!

And don't carry huge spare tubes and heavy tire levers.

I'm glad this was mentioned! I had a wheel built by Woody, a really nice 2.15-21" for my R100 GS. It was sealed as mentioned previously. With a TKC-80, i had three blow-outs in as many days, all at 80MPH!! After the third, the sealant was completely de-laminated. i removed it and fitted a tube. I contacted Woody and was told that they have been having problems with the TKC's sealing onto the bead, i could never find a leak (soapy water) and all blow-outs were quite instant. Truth is, i'm really not sure what failed, the sealant or the tire.
If i was to seal a rim, i would use Sikoflex marine sealant. First buff the aluminum with a stainless wire wheel to give the sealant some tooth, apply sealant and let it cure. Sikoflex will stick to aluminum permanantly, so this is a one way trip! Remember that the space where the spokes go is required for removing the tire, so your sealant could easily become damaged if your not careful.

... was told that they have been having problems with the TKC's sealing onto the bead..


Thanks for reminder as I'm about to try this. I presume you were using a TL TKC front, not an old TT or Tube Type (easily missed when ordering as I just found out)? Not that I'm sure what the difference in bead surfaces might be but I imagine the carcass of a TL tyre is better made to deal with plugs: here a rear TL TKC is 30% more expensive than a TT in the same size which one hopes is reassuring.

i could never find a leak (soapy water) and all blow-outs were quite instant. Truth is, i'm really not sure what failed, the sealant or the tire.

Would the marginally bigger diametre of a 21" make more centrifugal force to help delaminate it if it was not cured/stuck on well? Though would not tyre pressure hold it in place [did i mention this earlier?]? Even if it delaminated all at once would enough air leak out via the nipples to cause and instant blow out as you say?

If i was to seal a rim, i would use Sikoflex marine sealant. First buff the aluminum with a stainless wire wheel to give the sealant some tooth, apply sealant and let it cure. Sikoflex will stick to aluminum permanantly, so this is a one way trip!

Found 'Sikaflex Sealant 291'. Looks like '3M 5200' but 30% cheaper.

Remember that the space where the spokes go is required for removing the tire, so your sealant could easily become damaged if your not careful.

I would put the rim tape back over the sealant and/or wrap on some duct tape.

Ch

__________________
Adventure Motorcycling Handbook 8 • Morocco Overland 3 • Overlanders Handbook 2 • Twit

fill inner tube with proscribed amount of puncture seal, then;
1.find nail or screw, pull out
2.ignore 2-5
6.ride away

__________________
dave