Remember Kids, Inspect your rims regularly!

barry_kellett99

Found 3 nice splits in my rim wall yesterday morning![/url]

Nigel Bennett

You're lucky! You found it before it went BANG on the road somewhere.

Richard in our club had that on a club run a year or so ago, near Skipton. It was a rear wheel and it just stopped him dead. He ended up having to wade through a bloody great flood in the road to get to Skipton so his Missus could pick him up!

Shards of the rim could easily have skewered him in the leg - and if it had been the front, it would have been snogging the road time.

HamishD

barry_kellett99 wrote:

Found 3 nice splits in my rim wall yesterday morning![/url]

Eeek!

Valy

DAAAAAAMN!

Any ideas how that happened?

cougie

Thats what rims do. Every time you brake you wear a little of the rim. With time they'll get thin.

I had heard someone advising to pump your tyre up massively hard to see if that forces anything to split - but I think thats dangerous. If you're cleaning your bike - you should see these problems. And if you're not cleaning the bike - well you should be.

barry_kellett99

Rim has only done 11 months and less than 5000 miles
I think I may have contributed to the wear by having the rear wheel in the drop outs a little out of plum so one brake pad was rubbing a lot harder on the rim than the other when braking


PS - This bike never gets cleaned



It doesnt need it.

pinkbikini

Have seen rims go, luckily only to cyclists who are static at the time. It's quite an explosive noise!
Check your rims regularly, put a flat ruler against the rim and have a look from the side - a little concave is OK, massively concave is bad. You could either pump up the tubes to about 150psi and leave overnight to see what happens or, preferably, take to a decent mechanic to have a look.
Also check your brake blocks regularly and try and dig out all the metal shards, which accelerate rim wear.

MichaelW

The advice on proof-testing your rims includes wearing leather gardening gloves and eye protection. Take the pressure up 50% above the usual. Dont forget to let it down afterwards.

simonaspinall

I've had a full rim blow-out - During winter, even after cleaning the bike...it must've been a real hairline crack and didn't see it during cleaning.

It goes off like a gunshot! Fortunately it was on my back wheel so at least a bit more stable. However, the rim was completely shattered and wrapped itself right round my brake and meant a walk in the snow to work with the bike over my shoulder.

I am seriously careful with rim wear and cleaning my wheels from now on.

If it happened on the front it really would be catastrophic. :shock:

dodgy

barry_kellett99 wrote:

I think I may have contributed to the wear by having the rear wheel in the drop outs a little out of plum so one brake pad was rubbing a lot harder on the rim than the other when braking

I don't think that's possible with most braking systems, the pivots allow braking force to equalise no matter how badly they're set up.

barry_kellett99

dodgy wrote:

barry_kellett99 wrote:

I think I may have contributed to the wear by having the rear wheel in the drop outs a little out of plum so one brake pad was rubbing a lot harder on the rim than the other when braking

I don't think that's possible with most braking systems, the pivots allow braking force to equalise no matter how badly they're set up.

V-Brakes
The rim was slightly closer to one pad than the other So I was theorising that that pad was hitting the rim before the other one, therefore putting more friction and wear on that side

If it wasnt, then why would there not be a similar crack on the other side as well as the 3 on this side?

I've noticed that on really badly set up V brakes one pad hitting the rim a lot earlier will deflect the rim over to the other pad. The force through the first pad must surely be a lot higher?

dodgy

Well one side has to go before the other. And as you have V brakes, then you definitely can't exert more pressure on one side than the other regardless of how close one side is. It's physics (or something)

antfly

They might have lasted longer if they had been cleaned occasionally. :?

Mike Healey

K nowledgeably

I nspect

D eteriorating

S urfaces

Poacher

I've had a rear rim split over a 25cm length when a car driver cut in front of me and braked hard - he wanted to post a letter and had nearly missed the PO. The explosion was loud enough to add to Nottingham's reputation as gun capital of the UK. The driver was absurdly apologetic, but I assured him I was glad it happened on the flat @20mph rather than downhill @35. (And even more glad it wan't the front). Since then I've erred on the side of caution. Well done barry_kellett99 for spotting it in time (well, nearly ). A good time to develop your wheel-building skills.
Also a time to reprise my old tip for recycling knackered rims once you've dismantled the wheel (what? doesn't everybody re-use the hub and spokes?). Saw through the rim at the valve hole. With a bit of luck you'll be able to force the rim apart at the join opposite the valve hole - otherwise saw through the rim there. You now have two rim halves. No sh1t, Sherlock. Now make an old gardener very happy/confused. If necessary, explain to him that the half-rims are custom made supports for polythene, fleece or netting to protect his young plants next Spring, and they're an early Christmas present (after all, you don't want them cluttering up your kitchen, do you?
Brompton riders need not apply, unless they know someone who grows bonsai.

Edited: 25cm, not 25mm!

glebrus

What puzzles me,
why did so many people report rear wheel failure, not the front wheel?
I would expect most braking with the front wheel.
I mostly use the front brake,
and I've seen the front rim worn more in other people's cycles.
My experience is hybrid and MTB, is it different on a road bicycle?

Or is it because the pressure is generally higher in the back tyre? Or more weight sits there?

beverick

The front wheel is called on occasionally to stop the mass that the rear wheel is carrying continuously. The rear wheel, and rim especially, is also exposed to greater 'twisting' stress.

Almost certainly why only rear spokes fail.

BTW, re the original post, are you seriously saying that you needed to 'inspect' the wheel to find the damage. It will have been evident under braking for some time.

Bob

bumpitybump

Poacher wrote:

Saw through the rim at the valve hole. With a bit of luck you'll be able to force the rim apart at the join opposite the valve hole - otherwise saw through the rim there. You now have two rim halves. No sh1t, Sherlock. Now make an old gardener very happy/confused. If necessary, explain to him that the half-rims are custom made supports for polythene, fleece or netting to protect his young plants next Spring, and they're an early Christmas present (after all, you don't want them cluttering up your kitchen, do you?
Brompton riders need not apply, unless they know someone who grows bonsai.

Edited: 25cm, not 25mm!

LOL - great idea - I've got a pile of old wheels with worn out rims which I was planning to send to the metal recycling skip ...now I can see another use!

bumpitybump

Poacher wrote:

Saw through the rim at the valve hole. With a bit of luck you'll be able to force the rim apart at the join opposite the valve hole - otherwise saw through the rim there. You now have two rim halves. No sh1t, Sherlock. Now make an old gardener very happy/confused. If necessary, explain to him that the half-rims are custom made supports for polythene, fleece or netting to protect his young plants next Spring, and they're an early Christmas present (after all, you don't want them cluttering up your kitchen, do you?
Brompton riders need not apply, unless they know someone who grows bonsai.

Edited: 25cm, not 25mm!

LOL - great idea - I've got a pile of old wheels with worn out rims which I was planning to send to the metal recycling skip ...now I can see another use!