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Davey-boi
11-03-2004, 04:48 PM
Hey fellas, just picked up the latest "Scootering" mag and ran across this tire article. It was basically a how-to make vintage lambretta wheels into tubeless wheels. But I snipped out what I thought was some useful info to all scooterists.

***the following directly taken from "Scootering" ed. 220, October 2004.***


"Whats's so bad about inner tubes?

The main problem with tubes comes when they become punctured by something like a nail in the tyre. The thin rubber of the tube can actually end up tearing. This leaves the air able to escape rapidly through the gap between the split rims, often so quickly that it is virtually impossible to react when riding at high speed. With a tube a sudden front-wheel puncture almost always means a crash, though with luck and skill it is sometimes possible to save a rear wheel blow-out.

Further problem regarding inner tubes can occur if a split-rim wheel is incorrectly assembled. If the tube is pinchedbetween the rims then it will be under constant stress and can puncture unexpectedly at any time.

The final problem specific to Lambrettas is that the valves of certain brands of inner tube- Michelin Airstop are bad for this- can touch on the fork link bolt of the forks when used on the front wheel. This again can cause a sudden and terrifying blow-out with potentially horrific consequences.

Don't think that any of this can happen to you? Think again. Dave Dry of Classic and Modern Scooterist Scene had a sudden front wheel blow-out on his Lambretta earlier this year resulting in some nasty injuries and a very bent scooter.

What's so good about tubeless wheels?

Modern tubeless wheels are just as prone to punctures as those fitted with inner tubes- but the difference is in how the tyre reacts to whatever has impaled it. With a modern tyre fitted to a tubeless wheel a sudden blow-out is extremely unlikely. The far more common scenario when a nail penetrates the tread of the tyre is a slow deflation. The only place where air can escape on a regular tubeless wheel is through the penetration itself. If the hole is not too big then the air will only leak out gradually. This leads to the common "slow puncture" syndrome where you notice that a tyre is going flat when the machine is parked up or you feel odd handling when you first set off. Isn't this a better time to notice a puncture than flying over the handlebars at high speed?

On modern automatic scooters fixing a puncture is no harder than replacing a tube on a traditional machine. Highly effective tubeless tyre puncture kits are now available. These use thin wedge-shaped rubber bungs which can be coated with rubber solution glue and are inserted through the hole using a special tool. Once the hole has been plugged the tyre can be re-inflated using the tiny carbon dioxide bottles included in the kit. The whole process takes no more than 15 minutes. Of course if you had tubeless "traditional scooter" interchangeable wheels you could always just fit your spare.

The other advantage of tubeless wheels is that tyre puncture sealants such as Ultraseal are more effective. Ultraseal will seal a small hole in a tubeless tyre- permanently according to the manufactures- and also works on tubes, but not if the tube gets split by the intrusion. Only God performs miracles."

Zuma88
11-03-2004, 08:37 PM
very good post.

King Vino
11-03-2004, 08:49 PM
Sadly the problem is those of us running Sava white walls are stuck with the tubes, because of the tire construction won't allow us to run tubeless.

Zuma88
11-03-2004, 08:54 PM
here is a tip that maybe will work for you all, with tub tires take baby powder and rub it all around the tire and leave a little extra in it and the put the wheel back to geather this has saved my tire from damage a few times from tubs exploding

Davey-boi
11-03-2004, 10:48 PM
I remember vinniereno posting that with the vino wheels, you don't need to install tubes, even if the tire is a tube tire. Many vino riders don't even run their Sava white walls with tubes. I think he read on the tire that if you have a tubeless wheel, then you don't need to install the tubes with the tire.

Maybe you should take out the tubes King, it'll be a lot safer... especially since you don't really need em with the vino wheels.

King Vino
11-03-2004, 10:52 PM
We had tried to but ran in to issue with the stem mounting. Matt was unable to resolve it. Remember I'm running bigger tires than Vinnie was too which may be part of the problem. There was a post on the old board but no one was able to resolve the issue. I think it was only one of three posts I ever made about an issue.

devonrs
11-04-2004, 01:48 AM
...last time i was at the dealer (due to my third rear wheel flat tire, the first two -before i got the michelin s1's - due to hitting a big bump and the rim bending, and the third one due to just the rim being in such crappy shape from the previous bending back and forth that it just got flat out of nowhere) i got a new wheel and they installed a tube in the tire, i asked them why and they said it'll help keep the same problem from happening in the future, which makes sense with the problem i'd been having, if the rim bends the air will still stay in the tube... but as for the puncture thing, if the tire is set up like a tubeless tire, and has a tube in addition, wouldn't it be the best of both worlds? a puncture would still give you the tubeless result of a slow leak and a bent rim wouldn't give you a flat?? anyone?

King Vino
11-04-2004, 02:01 AM
That's what I'd think.

devonrs
11-04-2004, 11:05 AM
and i hope you're right. for a second there i was worried of a sudden tire blowout, though the tube is only in my rear tire, so i'll probably be okay even if that were to happen...

Davey-boi
11-04-2004, 02:28 PM
No you see, when a tube gets punctured its thin rubber rips which produces a huge hole inside the tire and air escapes really fast. Thus causing a blow-out.

Rosso Mandello
11-04-2004, 09:04 PM
Ah, but if the air rapidly escapes the tube, it will still be inside the sealed "tubeless" tire and wheel... makes since to me. However, if you are regularly hitting bumps hard enough to bend your rim, you will likely pinch the tube anyway and still have a flat. Run the maximum air pressure and swerve those potholes!!