Pre-stretching tubs

Therapysucks

All right. Been cycling a couple of years now and recently made the switch to tubs. May have been a dopey move, I know a lot of people on here have strong opinions on the subject, but the wheels were a bargain and I said I'd risk it for a biscuit. Anyway, am trying to get my head round all the extra preparation-for-disaster involved.

Am training for the Lost Sheep tri in Kenmare in September. Big race, lot of investment in entering and time spent getting my skinny ass ready. If I puncture, I don't want to walk away. So, everywhere I look for tips on changing a tub by the side of the road (which I haven't yet had to do), it says, have your replacement tyre pre-stretched and ready to go.

But if you already have tyres taped on to the wheels, fitted in LBS, you don't want to go whipping them off to stretch out a new tyre. Is there an alternative way of pre-stretching, or is there a way of getting the things on un-stretched at a fix? I had a crack at this before the shop guy stuck it on for me and I made a balls of it. Couldn't get it anywhere near around the rim.

Nearly all the guys I cycle with are as inexperienced as me, and none use tubs, so have no info from them. The LBS guy practically gave out to me for using them. I'm beginning to think the 'bargain' might have been just a bad spend. Either way, would appreciate any tips on having a spare ready for race.

I am aware of that gear to inflate a tyre in a pinch and will buy a canister. But also have a query about that. One of my taped on tyres has a valve without a removable core so the extender is over a permanently open valve. Will the sealant work as well with that type of valve? Is there any reason to expect hassle? The other tyre has a standard valve.

Tub logistics ... me head is melted.

AstraMonti

You need to have the tire pre-stretched and pre-glued in order to make a quick swap. If you haven't done it before then I suggest you practice, otherwise it will take you lots of time to do at the side of the road. If you are using tape and not glue, then it's all about luck, sometimes the tape comes out with the tire and some other time just sticks to the rim and you can apply the new tire. Whatever the case you need to prestrech the tire.

What you could do with a 50/50 chance to work is to carry something like this: http://www.effettomariposa.eu/en/products/espresso-family/espresso/ followed by half a canister of co2. There is more chance this working on the side of the road much faster than replacing a tire.

Good luck on your race.

Edit: You can pre stretch the tire on any rim, even clincher (not the best idea though), but you ll maybe find it hard to make the tire sit there while pumped. Alternatively just buy a very very cheap tub rib and use it only for stretching.

Therapysucks

Thanks for that Astra.

So, would you recommend that I take off the tyres I've just had taped on in the shop, stretch the new replacement tyres on the rims for a couple of days, and then practice getting them off and on as quick as possible?

I know that makes sense, just seems like an awful lot of work. And, lord knows, I devote my life to the avoidance of work.

I'll definitely have the espresso canister and CO2 option ready and hope no changing of a tyre will be required. Thanks for the link.

Sorry - just saw your edit. A cheap tub rim, that's an idea. Is the clincher for stretching a bad idea just cos it'll be difficult to make tyre sit when inflated, or might it cause damage in any way?

AstraMonti

The tire might not sit correctly on the rim and it won't be properly stretched. Some say a clincher rim will overstretch it some others say that it won't stretch it enough. I am not experienced enough to tell you the real story, but you can try, you won't damage the tire anyway.

I think a cheap mavic tub rim will be only 30-35euro, so it may be worth while if you are going to keep using the tubs.