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expoding rim

John C.John C. Posts: 2,113
edited March 2009 in Road beginners
This is why you take note of strange sounds. Full story on link below

Please post on both club web sites/newsletters Yesterday (Sunday 22nd) I was on a ride with Nigel, Colin and Tom from the Loiterers. We were just getting towards the hills to Lofthouse (riding West) and having ridden from Harrogate I was on about 25 miles. Going down to the ford near Ilton my rear brake lever (right hand in my case) started pulsing in my hand as I braked. I stopped once through the ford and found a buckle in the rear rim on the left hand side. It was suggested that I had hit one of the many potholes on the nearby roads, but I was pretty sure that I had not, I think I would have felt a hit big enough to do that. The rims are top end Mavics but they are about 15 years old, so I thought that it might be the start of rim failure. On this basis I decided to turn around and head home (via Masham) rather than tackle the steep down hill to Lofthouse with a dodgy rim, and/or get stranded 25/30 miles from home. I loosened off the rear brake quick release and set off, I can't say that I was riding slowly, about 18 mph for much of the way, but I was alert to further problems from the back wheel. Just North of Harrogate on the Ripon Road (just before the steep hill down past the car dealers) I heard a loud "pop" from the rear wheel. I pulled over and the original 1/2 inch buckle had suddenly stretched to about three inches. This confirmed my suspicions about rim failure and I set off again very slowly, hoping I would make it home. In another 100 metres there was a loud bang and the rim (and tube) exploded. As I was going slow (less than 10 mph) it was no big deal and I just pulled into the curb. The X5 rescue service (wife!) came out to get me and I got home safely having actually ridden 48 miles rather than the 50+ that I was expecting. Lessons:
1) do not ignore buckles that appear on your wheels for no good reason.
2) I have now read on the internet that current rims (i.e.not 15 years old) can fail after as little as one year of all weather riding
3) I could maybe have made it home if I had let some air out of the tyre (it was at my usual 120 psi) as its the air pressure that actually explodes the rim.
4) Yet another thing to be cautious about when going down hill fast! I will post a picture of the exploded rim next week, when I get back from this weeks business trip to USA.

Mike
http://www.ripon-loiterers.org.uk/

Fail to prepare, prepare to fail
Hills are just a matter of pace

Posts

  • DiogenesDiogenes Posts: 1,628
    Hi John,

    I have seen a rim go bang and if it were to happen at speed it could make for a troublesome time!.

    My touring wheels take a fair bit of hammer and just before the onset of winter I was becoming concerned with the wear on the rims so had them off for inspection. Not only were they worn but on the inside rear rim there was a crack just under the clinch rim running around the rim for about 3 inches. I tend to run my tyre pressures high even on my touring wheels which are up to 100psi. Needless to say a quick visit to my lbs set me up with two new wheels, ready for our Edinburgh to North Yorks run in June.

    Starting to get out again now after a fairly censored winter, been poorly for a while. Want to get fit for the Pocklington ride in April....are you doing it?

    D :D
  • dennisndennisn Posts: 10,422
    I have been riding for a "few" years and have neither seen or heard of this happening.
    Interesting to say the least.

    Dennis Noward
  • Yup, experianced this first hand. Not while riding though!

    On my gf's bike, she uses everyday round Bristol (some pretty bad-censored hills if you've ever been) and she normally has panniers loaded to the max too. Took the bike home, and I serviced it, pumped the tires up again to about 50psi (it's a MTB) and noticed about a 7 inch section of the rear rim had folded over. I looked at it, and decided it was just wear on the braking surface had weakened the rim, and the extra pressure in the tire was just too much.

    It does happen!!! :o:o:o
    Boo-yah mofo
    Sick to the power of rad
    Fix it 'till it's broke
  • Yup, experianced this first hand. Not while riding though!

    On my gf's bike, she uses everyday round Bristol (some pretty bad-censored hills if you've ever been) and she normally has panniers loaded to the max too. Took the bike home, and I serviced it, pumped the tires up again to about 50psi (it's a MTB) and noticed about a 7 inch section of the rear rim had folded over. I looked at it, and decided it was just wear on the braking surface had weakened the rim, and the extra pressure in the tire was just too much.

    It does happen!!! :o:o:o
    Boo-yah mofo
    Sick to the power of rad
    Fix it 'till it's broke
  • BronzieBronzie Posts: 4,927
    3176271551_1d2dfe4c27.jpg
    I did this in January to my old rear wheel which had just been relegated to use on the turbo (because I knew the rims were very worn). Just pumped up to 120psi and had literally only just started pedalling when.......................BANG! It was very cold in the garage that night (0°C), and I think this played a part.

    Scary thing is, my 13 year old son was using these wheels on his road bike recently, including a 50mph descent when we were in Normandy on hols in August. :shock:
  • John.TJohn.T Posts: 3,698
    Dennisn. You don't ride in British winters with all the farm cr*p on the roads. I change rear rims after 2 winters and fronts after 3 on average. In summer they last for ever.
  • dennisndennisn Posts: 10,422
    John.T wrote:
    Dennisn. You don't ride in British winters with all the farm cr*p on the roads. I change rear rims after 2 winters and fronts after 3 on average. In summer they last for ever.

    True. I've always claimed that I don't ride outside until the temperature is more than my age(60). If I did ride outside all winter I'm thinking that I would probably experience that sort of problem, what with all the salt that the roads crews use. My friends tell me it just eats a bike up.

    Dennis Noward
  • John.TJohn.T Posts: 3,698
    If I used that rule I would never get out Dennis. I does not get above 66 much here.
    They are right about the salt. It eats everything.
  • cougiecougie Posts: 22,512
    I have had it happen to one of my rims in the past. I dont go as high as 120 now though - about 100PSI seems fine to me. Some of my rims have lasted for years though - its good to keep the bikes as clean as you can I find.
  • John C.John C. Posts: 2,113
    Diogenes wrote:
    Hi John,

    I have seen a rim go bang and if it were to happen at speed it could make for a troublesome time!.

    My touring wheels take a fair bit of hammer and just before the onset of winter I was becoming concerned with the wear on the rims so had them off for inspection. Not only were they worn but on the inside rear rim there was a crack just under the clinch rim running around the rim for about 3 inches. I tend to run my tyre pressures high even on my touring wheels which are up to 100psi. Needless to say a quick visit to my lbs set me up with two new wheels, ready for our Edinburgh to North Yorks run in June.

    Starting to get out again now after a fairly censored winter, been poorly for a while. Want to get fit for the Pocklington ride in April....are you doing it?



    D :D

    check out my Easter Monday ride in the ride/sportive section , just ride Bransdale if you like, be good to see you again.
    http://www.ripon-loiterers.org.uk/

    Fail to prepare, prepare to fail
    Hills are just a matter of pace
  • jongingejonginge Posts: 5,945
    Same thing happened to me on tuesday. Riding along I thought I'd broken a spoke and then a few seconds later the tube blew...
    Broken rim pics here: http://www.bikeradar.com/forum/viewtopi ... start=9090
    FCN 2-4 "Shut up legs", Jens Voigt
    Planet-x Scott
    Rides
  • dennisndennisn Posts: 10,422
    jonginge wrote:
    Same thing happened to me on tuesday. Riding along I thought I'd broken a spoke and then a few seconds later the tube blew...
    Broken rim pics here: http://www.bikeradar.com/forum/viewtopi ... start=9090

    Nasty looking.
  • jongingejonginge Posts: 5,945
    dennisn wrote:
    jonginge wrote:
    Same thing happened to me on tuesday. Riding along I thought I'd broken a spoke and then a few seconds later the tube blew...
    Broken rim pics here: http://www.bikeradar.com/forum/viewtopi ... start=9090

    Nasty looking.
    Aye. Luckily I was on a flat bit of road and not surrounded by traffic. I started freewheeling when the rim started rhythmically bashing the brakes so I was only doing ~15mph when the tube blew.
    FCN 2-4 "Shut up legs", Jens Voigt
    Planet-x Scott
    Rides
  • cjcpcjcp Posts: 13,345
    Bronzie wrote:
    3176271551_1d2dfe4c27.jpg
    I did this in January to my old rear wheel which had just been relegated to use on the turbo (because I knew the rims were very worn). Just pumped up to 120psi and had literally only just started pedalling when.......................BANG! It was very cold in the garage that night (0°C), and I think this played a part.

    Scary thing is, my 13 year old son was using these wheels on his road bike recently, including a 50mph descent when we were in Normandy on hols in August. :shock:

    Exactly what happened to my rear Open Pro rim last year, just after a descent in nearby Richmond Park. I'd pumped them up that morning, although it was May, so not cold. As Cougie said, I tend to stick to 100psi now.
    FCN 2-4.

    "What happens when the hammer goes down, kids?"
    "It stays down, Daddy."
    "Exactly."
  • andrew_sandrew_s Posts: 2,511
    I've never had a rim explode on the road, but I've avoided it three times by checking the cause of pulsing brakes and taking immediate action.
    If you notice pulsing brakes (when you haven't just hit a pothole or stray rock), then...
    a) Stop and check immediately. Don't leave it to check later.
    A bulge caused by an incipient split makes the tyre edge of the rim bend outwards, and the braking surface will be very noticeably concave. If it's a pothole, anything big enough to be noticeable will also dent the rim inwards radially, towards the hub.
    b) Let half the air out of the tyre - down to about 50psi.
    c) Ride directly home, slowly enough that you can avoid potholes, and without using the brake on the affected wheel.

    I've had a rim fail in under 6000 miles, sooner than the Gatorskin that went on it when it was new. It's partly winter riding on steep and muddy lanes, but abrasive Shimano brake blocks also played a bit part. I do much better now I've switched to Koolstop.
  • John C.John C. Posts: 2,113
    I bought a pair of Mavic Cosmos wheels a couple of years ago, a wheel builder friend advised me to change from my Ultegra pads to some thing softer like Koolstop. I didn't and a year later I binned the new wheels as the rims were worn out :cry:
    http://www.ripon-loiterers.org.uk/

    Fail to prepare, prepare to fail
    Hills are just a matter of pace
  • Monty DogMonty Dog Posts: 20,614
    When lightweight MTB rims were the rage a few years ago, some rims would barely last a season - bowing of the braking track is a distinct sign of the rim being on it's way out. A rim usually cracks well before it goes 'bang' - keep an eye for long black cracks along the brake track that don't clean off. Running a coloured spirit marker pen along the rim and then try to wipe it off - a crack soaks up the ink and can't be wiped off.
    Make mine an Italian, with Campagnolo on the side..
  • John.TJohn.T Posts: 3,698
    I have been keeping an eye on my rear rim lately. It started to get brake judder this morning and by mid afternoon it had got worse. I should have let some air out then as it cracked 1/4 mile from home. I managed to save the tyre and tube but had to walk in. Now to fit the 4th rim on this hub in 9 years.
  • jongingejonginge Posts: 5,945
    John C. wrote:
    I bought a pair of Mavic Cosmos wheels a couple of years ago, a wheel builder friend advised me to change from my Ultegra pads to some thing softer like Koolstop. I didn't and a year later I binned the new wheels as the rims were worn out :cry:
    Oops. I should have done the same. My exploding rim was a Cosmos.
    FCN 2-4 "Shut up legs", Jens Voigt
    Planet-x Scott
    Rides
  • John.TJohn.T Posts: 3,698
    I am using Koolstop Salmon. The rims still wear out, just not as fast and they don't get gouges out of them.
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