Tyres - blowouts, causes and how to avoid them?

bmetcalf

Well Known and Active Forum User
VOC Member
Security Bolts

You guys are making me paranoid. I have been riding my Rap since 1980 with no security bolts on my rear steel rim with no problems. How long will that last?

Actually, one time I had a medium leak in the rear tube, while I had a very stiff sidewall Michelin tyre on and rode to a gas station at up to 30 mph, aired it up, then rode to a friend's garage to store it until I came back with a fresh tube. It was a bit squirmy and I didn't try any high speed cornering. I told the story to Dave Matson and he said the speed flings the tyre outwards and shouldn't be too bad in a pinch. His ideas of speed are different from mine, though.
 

John Cone

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VOC Member
Having read this thread from start to finish it accures to me that most people are running their tyres too soft. I have in a past life been a tyre fitter and fitted a lot of tyres to bikes. The use of proper tyre lubricant does not creat tyre creep as it dries out after a short while. On my Prince before it went into hibernation I ran it on Metzlers back and front with the pressures 28 front & 36 in the rear because you never know if and when you will need to go two up. Having Dunlop alloy rims I still use tubes with security bolts "whether you can still buy them I don't know". After having the bike off the road for the last 11 yrs i decided to check the tyre pressures, the front had only lost 5 psi the rear was down to 10 psi not bad me thinks!
 

Comet Rider

Well Known and Active Forum User
VOC Member
Modern tyre security bolts

Buyer beware!

Most modern tyre security bolts are designed for modern rims that have a deep well in the centre (such as motocross rims) and are unsuitable for our shallow well steel rims. The new style security bolts tend to trap the tube between the bolt and the sidewall of the tyre..

Neil

PS
don't ask how I found this out, it's painful:eek:
 

BlackLightning998

Well Known and Active Forum User
VOC Member
Unfortunately similar pain....

I had a similar embarrasing experience, I changed the tyre the night before going to the Riders Rally in York - put a new tube in whilst I was at it. I left the bike on the ramp and was chuffed with myself to be going to bed early around 10pm for a very early start the next morning - I thought, I'll just take it off the ramp, turn it around and be all ready for the off in the morning. Well you've guessed it, as I took it off the ramp I felt it heavy on the rear tyre - it was flat - I had nipped the tube as I put it in and fitted the tyre. So much for an early night, out with the wheel, off with the tyre and fit a second new tube (thank goodness I had one) - finally hit bed after 11pm.....

It happens.


Stuart
Buyer beware!

Most modern tyre security bolts are designed for modern rims that have a deep well in the centre (such as motocross rims) and are unsuitable for our shallow well steel rims. The new style security bolts tend to trap the tube between the bolt and the sidewall of the tyre..

Neil

PS
don't ask how I found this out, it's painful:eek:
 

Tony Cording

Well Known and Active Forum User
VOC Member
Tires and blowouts

Not much mention has been made of the ubiquitous valve stem. There were a couple of comments about the valve stems pulling out due to tire creep, which begs the question about what was done with the valve stem nut. The majority of us over here place the nut against the valve stem cap, not against the rim, to allow for some flexibilty in the event of minor creep. We haven't had any stems pull out, something to think about.

Tony Cording

p.s. Seen on a restaurant menue cover:

"He was a wise man who invented beer - Plato".
 

donrapide

Forum User
Non-VOC Member
Re: What size, is it for a solo? I've been using a 21" WM1 rim with originally Avon Speedmaster 21x3.00 tyres, which still seem to be available.

Not being keen on the milage from these I'm currently running a Pirelli 80x90x21 which seems to be a very good tyre. My tyre supplier, ex Speedway and now Sand Racer, tells me it is a Harley fitement so it has excellent speed and load ratings.

On my post war twin I have used, first 20", then 21" and finally 19" with a 3.60 section. (Due to availability over the years) The best for handling was the 21", then 20" and the very worst was the 19"x3.60. The 19" spoilt the steering and the handling.
 

wld50

Well Known and Active Forum User
Non-VOC Member
standard front wheel

Re: What size, is it for a solo? I've been using a 21" WM1 rim with originally Avon Speedmaster 21x3.00 tyres, which still seem to be available.

Not being keen on the milage from these I'm currently running a Pirelli 80x90x21 which seems to be a very good tyre. My tyre supplier, ex Speedway and now Sand Racer, tells me it is a Harley fitement so it has excellent speed and load ratings.

On my post war twin I have used, first 20", then 21" and finally 19" with a 3.60 section. (Due to availability over the years) The best for handling was the 21", then 20" and the very worst was the 19"x3.60. The 19" spoilt the steering and the handling.

For what I believe is the original for a standard Comet, WM1 3.00 x 20

I haven't managed to find a 20" inner tube, does anybody have any sources or ideas?
Should I use a 19" inner tube, or a 21" inner tube instead?

lyn
 
Last edited:

wld50

Well Known and Active Forum User
Non-VOC Member
Central Wheel Components

Dear Nkt267
When I initially found problems in obtaining a 20" inner tube locally for our 20" front wheel, I then contacted Central Wheel Components. They said that 20" tubes were no longer available and they now supplied a 'small' 21" tube.

Watling Tyres and a friendly local bike shop confirmed this unavailability, but both suggested using a 19" tube, the former said I wouldn't get a 21" tube in.

At this point with the jury 2:1 in favour of 19", I posted the query on the forum.

I've had one private reply to my posting who said he used a 21" tube, so we have 2 all.

Are there any more opinions out there?

lyn
 
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