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Sep 2008
12:19pm, 10 Sep 2008
5,075 posts
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Red Tomato
mine took 2 weeks to come through KR2, I suppose it depends on what company they are using.
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Sep 2008
12:57pm, 10 Sep 2008
719 posts
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Slowboy
Three tyre levers to get a stiff tyre back on.
Put the first bead back in, tube in, inflate a bit.
Start putting the other bead back in (I start AT the valve and work around the other way) once the bead is on 'a bit' push the valve stem back in through the hole a bit to make sure the tube isn't pinched by the valve.
Then work round the rim, pushing the bead back over with your thumbs. You need to work round from both sides at the same time.
You'll end up at a point where there's a stip of bead, stretched almost straight, which seems impossible to get back over the rim.
Push the end of a tyre lever up between the bead and the rim, just at the tight bit at one end. Don't try to lever it up yet - leave it 'trapped' by the bead, with the end pointing towards the hub. Then put the second one in at the other end - same drill.
Now put the third one up between the bead and the rim right at the very middle of the bit between the other two levers (damn, it's hard to describe this - I'm likely to be changing my own tyres later, maybe I'll post piccies)
This is the bit where it helps to have three hands......
Hole the outer two levers, and lever them both upward simultaneously - this'll pull the bead very tight, hopefully holding the third lever (in the middle) firmly in place. Keep holding one of the levers up - wedge the other one with your knee/thigh/prehensile willy or whatever to keep it pointing upwards.
Grab the middle lever and give it a good heave upwards - the bead will twang onto the rim, probably with a whip-crack noise of protest.
Go round the tyre both sides squeezing it away from the rim to make sure the inner tube hasn't been pinched. Then inflate and off you go.
The problem is keeping all three levers in at once....it may be necessary to lever one up, then hold it up by wedging it against your knee, whily you hold the middle one in and lever the other 'outside' on up.
I will srsly attempt to get photos of the process later....
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Sep 2008
1:00pm, 10 Sep 2008
731 posts
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i hate changing the tubing , would the aa or rac come out and do it for me
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Sep 2008
1:09pm, 10 Sep 2008
4,683 posts
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jude
I hope i never get a puncture 
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Sep 2008
1:17pm, 10 Sep 2008
5,076 posts
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Red Tomato
Thanks ( again!) slowboy, I know exactly what you mean as we got to this stage
'You'll end up at a point where there's a stip of bead, stretched almost straight, which seems impossible to get back over the rim.'
and thats where I battled for an hour or so, my husband did what you said with the 2 outer levers but I didn't think about using a 3rd to twang the middle section, he used his thumbs but I knew I couldn't do that. will have a hunt for my 3rd lever.
Haven't had a puncture for a year, then 2 in a couple of weeks! ( different bikes)
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Sep 2008
1:22pm, 10 Sep 2008
732 posts
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that straight bit your talking about RT , that is where i run into problems , i manage to get it in to the wheel but in doing so i end up catching the tubing and bursting it again arghhhhhhhhhhhhhhhhhhhhhhhhhhh
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Sep 2008
1:26pm, 10 Sep 2008
5,079 posts
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Red Tomato
I'm appalled tbh that my bike has been designed by a top class cyclist ( chris boardman) I can't believe the tyres are so difficult to get on, surely he must have had punctures on long rides/races? my old bike was much easier ( tyres stretchier, rim shallower)
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Sep 2008
1:31pm, 10 Sep 2008
3,242 posts
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hammerite
Rims are deeper for better aerodynamics.
Plus in road races they just whip the wheel off and put a new one on...... or if you are team leader someone else in the team gives them your bike. Chances are the wheels are someone elses as are the tyres. Generally with bikes the frame/set up is designed, then they put cheap wheels and tyres on (I know all about the cheap wheel thing, as I've had two spokes go in 3 weeks).
Amusingly Tyler the naughty boy had so many problems in the ToB yesterday that he had to borrow a bike from Team GB!!
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Sep 2008
1:31pm, 10 Sep 2008
720 posts
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Slowboy
You need to have the inner tube at the goldilocks stage of inflation - ie just right! Too hard or too soft and it'll end up pinched. UNfortunately finding that point is a matter of trial and error....
I've been thinking about how tight tires often are these days, especially folding ones, and I reckon it's down to the fact that they use a kevlar bead instead of a steel one.
Now, steel, whilst we think of it as being a fairly solid material, is quite elastic. So, when you try to lever a tyre bead into place it will stretch a bit (not a lot, but even 0.5% over the length of a tyre bead is going to be a few millimetres, which'll make all the difference).
Whereas kevlar... isn't elastic at all. The place where I work makes, among other things, braided packings, which look a bit like legths of woven rope. Some of them use yarns made from nylon, or cotton, or PTFE. If the guys set the braiding machines up wrongly and turn them on, all the yarns break.
Some of them use kevlar yarn...if the guys set the machines up wrong with that in, the MACHINES get broken. A 2mm diameter kevlar yarn can quite happily pull a steel and cast iron mechanism apart.
So I reckon when you try to stretch the bead over the rim, what's actually happening is that you have to deform the RIM to fit inside the bead, not the other way round...and the noise when it goes on is actually the wheel twanging straight again. It would certainly go some way to explain why the buggers are such a pain in the posterior.....
The only pair of foldable tyres I've ever had thet were possible to put on easily also popped back off again if you hit a bump at speed...not ideal
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Sep 2008
7:58pm, 12 Sep 2008
267 posts
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EyeSpy21
Cycling for the Overweight
My sister is obese/morbidly obese but has shown in an interest in cycling to work.
How do we go about choosing a bike? Are there weight limits/specifed max user weight? Specialist bikes? Or will any bike do but maybe not expect it to last as long? Some sort of step through street bike would be good (will ask her to check 'cycle to work' options with her company)
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