Tubeless conversions

Max said:
I have used engineering epoxy to bond a suitable flat washer into rims for the valve to seal onto. “Off highway use only” and other disclaimers.
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Very good idea.

On the subject of corrosion a lot of it is caused by using soap as a lubricant (caustic) when fitting the tyre instead of recommended lubricant.
I've come across many cast aluminium wheels (3cl onwards) suffering from severe corrosion due to soap or inappropriate lubricants being used and the caustic element trapped Causing erosion between the tyre and wheel rim flange.
Don't use soap.
 
I’ve been running tubeless on my cast Laverda wheels for decades without issue. However, managed to pick up a front puncture on my Mk 3 Atlas last year, fortunately at slow speed, had a new tube fitted professionally and it still deflates slowly... 😕
However, Some of my tubeless Zane wheels leak due to the powder coating failing.
 
It is perfectly clear that you absolutely advise against this, we have heard. Yes as you say us idiots can do what we like to jeopardise our own safety. Many people have run with this for countless kilometres, maybe they can chip in with all the tyre off the bead incidents they have suffered. And virtually everyone has had a major job getting a tyre off the bead of the rims we use here. Informed decision.
 
(Specifically Alu Lav wheels, as is my experience in converting)

All I know is...
1 - I once rode 30 miles with a completely flat rear tyre, slowly of course, but 30 bloody miles. They tyre stayed perfectly in situ, the bead still being tightly locked in the right place.
2 - Every time I try to get a tyre off, it's an absolute bastard to do.
3 - Every time a tyre fitter tries to get a tyre off for me he says it's bloody hard to get off.

Forces in a high speed blow out are incomprehensible, but I think the Lav rim happens to retain the bead very very well, despite not being designed specifically for tubeless.

I kinda like being alive, so have thought long and hard about it, and for me, it's safe enough. I would not go back to tubed.
 
Doesn't really matter tube or untubed. It's the potential aftermath when the tyre has become unseated. I've had one of each type happen to me while on the bike. The instant deflation was like riding a bucking bronco. The other a slight squirming around given me plenty of notice to slow up. Both these were rear wheeled thank goodness. The thoughts of what you face with front chill me.
 
martymoose said:
Got 1 roll coming, 16.5m, will do around 10 wheels. You can argue back and forward all you want, I'm scared of riding on tubes made in a country where there is no word for quality.
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martymoose said:
Pirelli tube made in china was the one that let go on the seam, 6 inch long split and instant deflation at 120km/h around a sweeper. Huge tank slapper and change of underwear needed. Currently using Vee rubber brand made in Thailand
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I've fitted Vee Rubber inner tubes for quite some time, no issues at all. They look sturdy and well-made, and still look OK when they're replaced at the next tyre change.

Rims for type-type tyres are generally not air tight at the bead seating, sudden deflation causes immediate collapse. Even a small puncture from a nail can cause the tube to split, depending on tube quality. Tubeless-type rims are generally air tight at the beads, a sudden deflation due to a simple puncture is far less common, the tyre has to be slit wide open for a sudden deflation.

Because the Laverda cast rims have a too-large diametre at the bead seating to start with, the tyre will mostly stay in place after a sudden deflation. It's also the reason they're a bitch at tyre renewal time. IIrc, Keith once modified Laverda rims for tubeless fitment, forming the "safety" hump for the bead and generally allowing for easy/normal effort during tyre fitting. Only way to go, imho...

As already stated, thick, enduro-type tubes will not protect you from puntures, they are only a bit more resistant to pinching due to the low pressures used in off-road use. The weight penalty alone and all ensuing disadvantages rule these out for road use. Waste of money...

piet
 
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Vince said:
Quick question, should you replace the tube when you replace the tyre, every time?
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Well, it is recommended... by the tyre industry. Make what you like of that. :rolleyes:

Personally, I re-use tubes 2-3 times if no damage, chafing, etc is visible. After changing my own tyres for more than 40 years, I now have to rely on others to change my rubber and I'll most probably be caught up in "the tube has to be renewed for liability reasons" sales dribble.

I was willing to "risk" a used tube when changing my own tyres and never had any issues. Been a long time since I last had a puncture, or any sort of tyre damage for that matter.

piet
 
Re-use tubes all the time. I check them carefully before re-using. Yes, Laverda cast wheels are the hardest to fit a tyre to, well is not deep enough, and that double lip on the outside is just waiting for the machine to dig into it. I hope nobody is still trying to use thin web wheels......
 
sfcpiet said:
I've fitted Vee Rubber inner tubes for quite some time, no issues at all. They look sturdy and well-made, and still look OK when they're replaced at the next tyre change.

Rims for type-type tyres are generally not air tight at the bead seating, sudden deflation causes immediate collapse. Even a small puncture from a nail can cause the tube to split, depending on tube quality. Tubeless-type rims are generally air tight at the beads, a sudden deflation due to a simple puncture is far less common, the tyre has to be slit wide open for a sudden deflation.

Because the Laverda cast rims have a too-large diametre at the bead seating to start with, the tyre will mostly stay in place after a sudden deflation. It's also the reason they're a bitch at tyre renewal time. IIrc, Keith once modified Laverda rims for tubeless fitment, forming the "safety" hump for the bead and generally allowing for easy/normal effort during tyre fitting. Only way to go, imho...

As already stated, thick, enduro-type tubes will not protect you from puntures, they are only a bit more resistant to pinching due to the low pressures used in off-road use. The weight penalty alone and all ensuing disadvantages rule these out for road use. Waste of money...

piet
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I remember Keith modifying rims and think it is a worthwhile modification. Do you have any details on the dimensions for the best result? I haven't seen Keith around here lately or I would ask him.
 
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Reunited Chris said:
Very good idea.

On the subject of corrosion a lot of it is caused by using soap as a lubricant (caustic) when fitting the tyre instead of recommended lubricant.
I've come across many cast aluminium wheels (3cl onwards) suffering from severe corrosion due to soap or inappropriate lubricants being used and the caustic element trapped Causing erosion between the tyre and wheel rim flange.
Don't use soap.
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My Corsa wheels when I bought the bike and started the rebuild the inside of the wheels were shocking both running tubeless. Lots of debris and corrosion particulary in the front wheel and it was really 'wet' tyres had little wear. I assume it had had tyre sealant pumped in at some point? Not nice! All sorted now back to tubes and new tyres. Opinions vary I know on polish and paint or powder, but blasted and powdercoated black and silver by Lankies Powdercoating top chap who was at Willersley 75th.
 

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Hate powder coated rims. Club member just bought me a set of rims off a 25 year old Suzuki to fit new tyres. He had just had them re- powder coated. The size of the wheel now much bigger due to the second coat , a real struggle to get the tyre on. Originally anodised , I reckon probably 2mm of coating now. What a disaster......
 
martymoose said:
I use a black soap to fit tyres which is non corrosive. Made by Wurth.
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Yeah, that stuff is impressive!

I've found the old Gixxer rims to have a quite thin but very tough powder coating. Lots of effort needed to remove mechanically (really abrasive medium is needed for blasting), probably some sort of chemical concoction might make short work of it.

Don't know of any dimensions for tubeless rim mods, but surely can be copied from a dedicated tubeless rim, still a few in 18" around.

piet
 
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