Am I the only person who's thought of this ...?

[JawasandMZs]

I've had a spate of rear wheel punctures my Jawa lately. Once thanks to a good honest screw in the tyre and twice due to the tube chafing against the corroded surface inside the rim.
Now I've taken a damaged tube, split it round the outside, and used it as a sleeve without a stressed surface to protect the inflated tube from the rough surface of the rim.

Obviously I now think I'm a total genius and I'm happy if this tip helps anyone else. I'm going to do it as a pre-emptive precaution every time I fit a new tyre from now on.
Or has this trick been around for yonks already?

[Jay Bee]

You sure there's sufficient space inside the tyre for this ?
And are you quite sure it won't overheat ?
What's wrong with a conventional rim tape, anyway ?

[Puffs]

Tom, it is not an approach I was familiar with. Off the cuff: it may be a bit more difficult to get the dressed tube inside the tyre, but as people also manage with tyre mousse, that should be doable. The Jawa rims are, uhm, spacious enough, so it should fit. But my main question is: Why?

For protection from a rough steel rim, with loose corrosion parts, surely it should give some protection, but the more common approach to that is to properly clean the inside of the rim, and sand/filla it as required, and spray it with some protective coat. Tape may give problems with proper seating the tyre. I'm not talking about tape (or another cover) over the recessed nipples, that is common practice. But I actually wonder why the tube is chafing against the inside of the rim, shouldn't that just sit still under pressure?

Anyway, why not give it a try & please let us know how you fare!

[Blurredman]

A wide rim tape is good for the inside of the wheel, or should be.

But if trying to prevent punctures, surely the split in the old inner tube should be in the inside, so that the majority of the unbroken surface is on the outter side of the tube (against tyre) ?


Interesting idea though I've actually only had a handful of punctures, despite riding for 12 years now.

[JawasandMZs]

Hi all and thanks for your comments. Just been out an hour's ride (ie, about 20 miles how I ride!) and the tyre's still up. What I've installed is, effectively, extra wide rim tape. With hindsight I could've trimmed the outer tube to the width across the rim (including the dip, obviously!) and avoided the excess riding up inside the tyre wall.
I don't think this info will be needed on MZs, aren't they all aluminium rims?
This might helpful if any of you young lads ever get hold of a classic GT250 or 4/4

[Gerryman Ts125]

When I was a motorcycle courier, the cyclists on quite a few companys used to put a worn out old rubber tyre, inside their newer tyre (the old one were mostly Kevlar lined) to prevent punctures. So I reckoned it would work with my motorcycle tyres.

So I asked them for a wide worn bike tyre, to fit on my long list of Ar 125`s and other tubed tyre`d motorcycles (the tubeless ones I would remove the penetrating object with pliers, and stuck a large fatheaded self tapping screw into the hole it left and re-inflate them with a small footpump I kept in my topbox)

And it indeed did, or I was very luckly avoiding punctures. Most punctures are cause by your front tyre throwing a nail or pointed projectile into your rear one.

[Puffs]

Indeed, nails and screws and so normally lay flat & harmless on the road, so they need the front tyre to move them in a position ready for attack!

Surely placing the tube farther away from puncturing object coming from the outside, will reduce the chance of punctures. And yes, particularly for bicycles there are 'puncture proof' tyres with kevlar, which is indeed surprisingly strong & resilient. But the OP did this to prevent the tube from abrasion by the corroded steel rim. Less of an issue with MZ's (or CZ's) aluminium rims, but the Jawa has steel rims.

My Jawa is getting on to 50 years, and while it hasn't seen too much rain, nor has it ever done courier service, of course the rims have some corrosion. They are still original. I treat the inside as described above, as required, when I change tyres. I don't think I ever had a puncture with that bike.

Having a puncture is a major hassle. With a Jawa (or MZ) you're lucky to have a decent centre stand, so that the wheel can easily be removed - but still, major hassle with tyre irons, fitting a spare tube (or glueing the old one), and getting it all back together. Even if you have all the tools, a lot of time. Indeed in a tubeless tyre things are a lot easier: the wheel can stay in, and nowadays you'd plug the hole with a mushroom plug. I'm considering to convert another bike (spoked wheels w/ aluminium rims) to tubeless, also because it saves weight & angular momentum.

And then of course, if you want to prevent the hassle of a puncture at the road side, consider the mousse I mentioned earlier: https://www.motosport.com/blog/what-you ... ire-mousse.

Ta for raising this interesting topic Tom!

[Gerryman Ts125]

I used to find that new tyres with at least 8cm of tread would help, as the puncturing objects had further to travel before leaving the tyre and getting to the tube. But as the tyre wears, it is easier for objects to either pass through the tyre, or objects already in the tread puncture inwards, after a sharp bump.
Most of the motorbikes I hacked on, I always had a set of spare wheels and tyres waiting for a puncture to happen. My Mz Ts bikes were the easiest to turn around. All I had to do was release a couple of bolts and stick on the spare wheel. No discs to aline, and chain and back sprocket too. And the brakes were crap, unless it was raining. For one reason or the other, the rear brake locked up by just the slightest touch. In the dry they would take forever to even stop accurately solo. Even with Dunlop K82's fitted or a pair of Continental Z7 tubed small touring tyres on it. Gave up driving ( after two years on and off) it after I fell off so often and only used it sparingly off road. And it was fantastic, until you had to stop. But plenty of run off areas

[Jay Bee]

By coincidence, I am presently replacing the rear tyre of my 1960 Royal Enfield owing to cracks appearing in the sidewalls caused by aging.
Removing the old tyre revealed a (steel) rim whose well was red-rusty as an old horseshoe - 62-year old rim, and so no surprise there.
What was a real surprise was that no rim tape was fitted - the tube was sitting directly on the rim / spoke nipples - and rust !
No puncture, no patches.....Impossible to say how long it's been like this, of course, but I've owned the bike for 20 years. The inner tube shows slight "dimpling" where it's sat against the spoke nipples, and also has the figure "73" moulded in : I'm taking this to be the year of manufacture. I've treated and painted the rim well and cleaned up the tube, which is still quite re-usable at a push, but I'll be renewing it anyway in view of its age.
In view of the foregoing, I cannot imagine how bad the rust must be on your Jawa wheel .....

[JawasandMZs]

PLUS ... my genius invention protects against nipping the tube whilst fitting a tyre.

[Puffs]

Tubes too come in quality grades & thicknesses, a thick one is less likely to be nipped during fitting. And apparently survives for decades even without tape over the nipples... Indeed, your rim must have been quite bad to cause a tube to puncture! And that in just - what is it, 7 years or so?

[Gerryman Ts125]

Tubes also explode at high speed, especially under continuous braking. Hence why tubeless tyres are needed in racing (and first assembly/cheaper.to manufacturer) As the tubes overheat. Causing. You guessed, punctures. My uncle had a Tri thunderbird combo in the late fifties/ sixties ( sold the side car) kept his Tri Thunderbird for his weekends off, and bought a mini Austin seven. And when he had the combo, he would not even take the wheel off the bike, he would just remove the tyre where the tube was punctured, patch that part, shoehorn that part of the tyre back on, inflate it as few times to enlarge the tube, so he never 'nipped it'. Fully inflate it. And carry on his way. His tyres had no sidewall strength. But he did have a good set of levers. He was a merchant seaman/docker so had arms like Popeye.

[Puffs]

Forgive my ignorance, but how can a tube explode when it is still inside the tyre? Or does the tyre explode with it?

There are speed ratings for tyres, and of course tyres (both with and without tubes) heat up due to the constant flexing when rolling at speed. That's caught in the speed rating, at the prescribed pressure; increased pressure reduces the flexing. So don't go racing with too low tyre pressure.

Maybe those historic tyres in your uncle's days were more like bicycle tyres still are: more flexible, and possibly with more clearance on the rim? Yes, those you can do with the wheel still in the bike. But that won't work with modern tyres... Anyway, I take the wheel out.

[Gerryman Ts125]

Forgot to add once repaired with a *patch* the patch lets go, the tube stretches hole enlarges. Instant deflation. That`s why I very seldom repaired a front puncture with a patch more that once. Easier to save a rear tyre blow out than a front. Cause shi** happens. Mostly in your own trousers.

[Puffs]

OK, ta for the reply. Yes, a patch coming off is something I can visualise.

I was just wondering, because I suspect that in racing, in the pre-cast wheel period (say before 1970), they used tubes. Like in this £210k moped:


My old bikes have old tubes (often with patches), and my problem with those is that they seem to be come permeable; I need to check their pressure & pump a bit. Last year my MZ received a new tube (because the valve had sheared) - and that does keep pressure!