Wheel and arm bent

Roja Doja wrote: ..............

Quoted message said:

I hit the kerb between pavement and road where the
pavement ramps down to the road, so the kerb was not more
than 2 or 3 cm high.

Can you go back and measure the exact height to check?

Quoted message said:

It was at quite an oblique angle (i.e. I went up the kerb
almost parallel to it , not straight at it) and I was
doing about 20mph or less. Should this cause a MTB wheel
to fail?

First of all, regardless of wheel strength, it's really
dangerous to go up a kerb at an oblique angle, full stop.
You can loose control all too easily, as you've found.
Always take any kerbs straight on and at low speed, easing
your weight off the wheels.

Wheels aren't always built very well (in terms of spoke
tension) but it's highly unlikely that the *rim* was not of
"merchantable quality" or "fit for the purpose" when you
bought it. Even the cheapest rims tend to stand up to all
normal use ok in this respect.

If the rim is actually dented in (with a distinct dent in
the sidewall edge) then it's probably entirely your fault.
That usually means the tyre was soo soft or you had a severe
impact. A minor bump couldn't do that.

If not dented but the wheel is buckled, again that could
just be from the impact, but poor building can
contribute: by spokes being under, over or unevenly
tensioned. The supplier could possibly be to blame then,
but I think it's unlikely.

Another very real possibility (especially if no distinct
dent in rim) is that you lost control because of the oblique
angle and the wheel buckled *after* the initial impact. That
would definitely be entirely your fault.

Anyway, hope the injury heals quickly (that's more
important).

Note: Wheel can be rebuilt using existing hub and spokes.
Don't need a whole new wheel.

~PB

Roja Doja posted ...

Quoted message said:

Am I going mad? Assuming you believe I'm telling the
truth, and that I really didn't ride it into a wall at
50mph or something similary stupid, shouldn't a mountain
bike wheel take a bit more stick than this?

Riding up a kerb is a big no-no .. especially on a cycle. If
you kit a kerb square, or nearly square on, then you can
sometimes get away with it, but more often than not you'll
hit at an angle, as you describe, and the tyre simply won't
be able to grip enough to go over the kerb, so 'slips off'
sideways, probably buckling the wheel - this sounds exactly
what you've done. Whenever I go up a kerb I lean way back
and lift the front wheel up, then bunny-hop the rear over
the lip, as though it's a jump lip .. I rarely do this at a
very (nearly parallel you said) oblique angle, unless I'm
doing a full bunny-hop, the tyres simply can't cope .. and
neither can _any_ wheel .. 😉

Quoted message said:

Doesn't the fact that the wheel is badly bent indicate
that it's failed?

Depends how badly bent badly bent is. If the rim has _any_
kinks or steps, or dents in it then I'd never use it again.
If it's bent further than, say, 30 degrees from straight
then again I'd never use it again except in an emergency,
though a lot depends on exactly how it's bent, and is hard
to describe adequately without a picture .. 😉

In the situation you have described the wheel isn't being
used in any 'normal' manner of riding, including competition
riding, and is almost definitely unlikely to be covered by
any potential warranty.

Quoted message said:

Shouldn't the shop be a bit more sympathetic??

Why ? If you ran up a kerb without un-weighting the front-
end then you possibly deserve all you get .. and have been
very lucky to get away so lightly.

PS Get well soon .. 😉

--
Paul

(8(|) Homer rocks .. 😉

in message <[email hidden]>, Roja Doja

(') said:

Hello again,

I posted here about a month ago, enquiring about how much
I should spend on a new bike. After reading the many
helpful responses, I bought a new Trek 3500 with semi-
slick tyres and was happily riding it to work and back
every day.

On Tuesday, I was almost home, cycled off the road onto
the pavement near my house, and before I knew it I'd gone
over the front and hit the ground, the bike flipped over
once and then stopped. When I picked myself and the bike
up, I noticed I couldn't push the bike as the wheel was
bent quite badly. Since the bike didn't hit anything else
after I fell off, I can only assume that the wheel must've
bent as I hit the kerb, and the bent wheel was what caused
me to crash (it's a perfectly straight bit of road
pavement, not the sort of place where you think anyone
could have an accident). In the fall I fractured my radius
near the elbow, which is proving to be a considerable
nuisance!

I hit the kerb between pavement and road where the
pavement ramps down to the road, so the kerb was not more
than 2 or 3 cm high. It was at quite an oblique angle
(i.e. I went up the kerb almost parallel to it , not
straight at it) and I was doing about 20mph or less.
Should this cause a MTB wheel to fail?

It most certainly should not do. I assume it was the front
wheel which bent? Was your tyre reasonably hard? Had you had
any problems with broken spokes before? Did you break any
spokes in this incident? Do you have any memory of the
handlebars twisting round violently in the incident (wheels
are much less strong laterally than they are to forces
perpendicular to their axis)?

The oblique angle may have something to do with it (not
generally a good idea if you can avoid it) but given the
very small size of the bump I'm surprised.

Quoted message said:

I was pretty incensed at this, and suggested that a 3 week
old mountain bike wheel should not be expected to fail
going over a 3cm kerb at 20 mph, and that as such it
wasn't fit for its purpose.

I'd agree with that.

Quoted message said:

Am I going mad? Assuming you believe I'm telling the
truth, and that I really didn't ride it into a wall at
50mph or something similary stupid, shouldn't a mountain
bike wheel take a bit more stick than this?

Yes. It _must_ do, otherwise it isn't safe. Even quite
ordinary off-road cycling involves hitting things a lot
bigger than 3cm at 20mph and more. One of my regular runs
involves coming down a stone chute with rocks the size of
turnips[1] and I must hit them at at least twenty.

Quoted message said:

Doesn't the fact that the wheel is badly bent indicate
that it's failed? Shouldn't the shop be a bit more
sympathetic??

Yes. But I have some sympathy for them, too. People do do
ridiculously silly things on bikes. Still, in this incident,
with a near new bike I would have thought a free replacement
or rebuild would be the least they could do.

[1] Not your namby pamby little white English turnips.

--
[email hidden] (Simon Brooke)
jasmine.org.uk~simonOpen ↗ ;; Skill without
imagination is craftsmanship and gives us ;; many useful
objects such as wickerwork picnic baskets. ;; Imagination
without skill gives us modern art. ;; Tom Stoppard, Artist
Descending A Staircase

"Roja Doja" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Hello again,

I posted here about a month ago, enquiring about how much
I should spend

on

Quoted message said:

a new bike. After reading the many helpful responses, I
bought a new Trek 3500 with semi-slick tyres and was
happily riding it to work and back

every

Quoted message said:

day.

On Tuesday, I was almost home, cycled off the road onto
the pavement near

my

Quoted message said:

house, and before I knew it I'd gone over the front and
hit the ground,

the

Quoted message said:

bike flipped over once and then stopped. When I picked
myself and the

bike

Quoted message said:

up, I noticed I couldn't push the bike as the wheel was
bent quite badly. Since the bike didn't hit anything else
after I fell off, I can only

assume

Quoted message said:

that the wheel must've bent as I hit the kerb, and the
bent wheel was what caused me to crash (it's a perfectly
straight bit of road pavement, not

the

Quoted message said:

sort of place where you think anyone could have an
accident). In the fall

I

Quoted message said:

fractured my radius near the elbow, which is proving to be
a considerable nuisance!

I hit the kerb between pavement and road where the
pavement ramps down to the road, so the kerb was not more
than 2 or 3 cm high. It was at quite

an

Quoted message said:

oblique angle (i.e. I went up the kerb almost parallel to
it , not

straight

Quoted message said:

at it) and I was doing about 20mph or less. Should this
cause a MTB wheel to fail?

I took it back to the shop today, expecting sympathy,
explanations, a replacement wheel and perhaps apologies. I
didn't get any of that.

Looking

Quoted message said:

at the wheel, they agreed it must've been some sideways
force that bent

the

Quoted message said:

wheel, as there were no marks on the rim that would've
indicated a big impact from the front, they looked at it
in more detail the workshop, then said it was too bent to
repair and suggested I buy a new one. I was

pretty

Quoted message said:

incensed at this, and suggested that a 3 week old mountain
bike wheel

should

Quoted message said:

not be expected to fail going over a 3cm kerb at 20 mph,
and that as such

it

Quoted message said:

wasn't fit for its purpose. They looked at me with
disbelief, shrugged

and

Quoted message said:

said the only other thing they could do was send it back
to Trek for analysis and see what Trek had to say, so I
agreed to that.

Am I going mad? Assuming you believe I'm telling the
truth, and that I really didn't ride it into a wall at
50mph or something similary stupid, shouldn't a mountain
bike wheel take a bit more stick than this? Doesn't

the

Quoted message said:

fact that the wheel is badly bent indicate that it's
failed? Shouldn't

the

Quoted message said:

shop be a bit more sympathetic??

Roger

I've "pringled" a front wheel in an offroad crash doing much
less than 20mph. A 20mph impact is pretty heavy duty!

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

They looked at me with disbelief, shrugged and said the
only other thing they could do was send it back to Trek
for analysis and see what Trek had to say, so I agreed
to that.

IANAL but Sale of goods act is your friend. You bought an
ATB/MTB whatever, and you can therefore reasonably expectg
it to cope with 2cm bumbs in the road, no matter that it was
a droped kerb, nor what angle you hit it at. The wheel was
NOT fit for purpose, Wheels are meant to be round, yours
isn't any more, ergo it failed under conditions that could
reasonalbe be expected to be encountered. Secondly, your
contract is with the retailer not the manufacture, it is
their responsibility to refund or replace.

Steps to take, read this
dti.gov.uksalegoodsact.htmOpen ↗
points one to five inc are the pertenent ones go back to
the shop and ask for are fund in accordance with the sale
of goods act right it all down and visit the shop again
giving them a copy. tell them that your next step will be
to contact the tradign standards office contact TS, and
also get a small claims court claim form SUE the [censored].
Main problmes I see are a) you've already let them have
the wheel,
b)It's your word that you didn.t do a drop off from the top
of your house

Good luck.

oh and I hope your arm heals soon.
--
.paul

If at first you don't succeed... Skydiving is probably not
the sport for you.

Roja Doja said:

Am I going mad? Assuming you believe I'm telling the
truth, and that I really didn't ride it into a wall at
50mph or something similary stupid, shouldn't a mountain
bike wheel take a bit more stick than this? Doesn't the
fact that the wheel is badly bent indicate that it's
failed? Shouldn't the shop be a bit more sympathetic??

I'd say it's a dodgy wheel, or that it's not been built
quite right and has started to go slightly out of true then
buckled as you hit the kerb. FWIW, as a kid I once had a new
front wheel after buckling the old one (probably from riding
straight up normal 6" kerbs), and whilst riding down the
street the new rim gave up, splitting at the dowelled
section where it's joined. Bike shop bloke had never seen it
happen before, and he's been around a while.

"Pete Biggs" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Roja Doja wrote: ..............

Quoted message said:

I hit the kerb between pavement and road where the
pavement ramps down to the road, so the kerb was not
more than 2 or 3 cm high.

Can you go back and measure the exact height to check?

As it's just outside, yes! It varies between about 1.5 to
2.5 cm (which seems almost nothing kerb-wise)

Quoted message said:

Quoted message said:

It was at quite an oblique angle (i.e. I went up the
kerb almost parallel to it , not straight at it) and I
was doing about 20mph or less. Should this cause a MTB
wheel to fail?

First of all, regardless of wheel strength, it's really
dangerous to go up a kerb at an oblique angle, full stop.
You can loose control all too easily, as you've found.
Always take any kerbs straight on and at low speed, easing
your weight off the wheels.

Easy if you're crossing a road, but I guess if you're coming
off a busy road, you can't really pull out into the middle
of the road so you can turn towards the kerb straight-on can
you? At least I've never seen anyone attempt that! Perhaps I
should've pulled over and got off, then lifted the bike onto
the pavement, maybe if I had a race bike with super skinny
wheels I'd have been more inclined to do that, but I assumed
it wouldn't be a problem riding a mountain bike with bit fat
tyres, it's never been a problem before. My arm tells me I
was wrong though!

Perhaps the rock-hard tyre pressures and aluminium frame
make the new bike more of a precision-machine, and maybe
it's more unforgiving than the [censored] old bikes with half-
inflated tyres I was used to riding.

Quoted message said:

Wheels aren't always built very well (in terms of spoke
tension) but it's highly unlikely that the *rim* was not
of "merchantable quality" or "fit for the purpose" when
you bought it. Even the cheapest rims tend to stand up to
all normal use ok in this respect.

If the rim is actually dented in (with a distinct dent in
the sidewall edge) then it's probably entirely your fault.
That usually means the tyre was soo soft or you had a
severe impact. A minor bump couldn't do that.

No dents, and the tires (and ride) are rock hard, as
supplied by the shop.

Quoted message said:

If not dented but the wheel is buckled, again that could
just be from the impact, but poor building can contribute:
by spokes being under, over or unevenly tensioned. The
supplier could possibly be to blame then, but I think it's
unlikely.

Buckled is probably the word, looking along the line of
wheel, it's bent/warped into a kind of s shape, but looks
otherwise ok, no dents, tyres still pumped up and OK.

Quoted message said:

Another very real possibility (especially if no distinct
dent in rim) is that you lost control because of the
oblique angle and the wheel buckled *after* the initial
impact. That would definitely be entirely your fault.

I'd concede this is a possibility, I'm just not sure how my
losing control and then falling off could cause the wheel to
buckle? The bike didn't hit anything, I had my hands on the
handlebars, it just kind of wobbled, stopped, I went over,
the bike tipped over and then hit the ground. Without my
weight on it, I'd have thought that was even less likely to
be the cause of wheel buckling?

Quoted message said:

Anyway, hope the injury heals quickly (that's more
important).

Thanks.

Quoted message said:

Note: Wheel can be rebuilt using existing hub and spokes.
Don't need a whole new wheel.

Yes, I guess that was what they meant when they talked about
a buying a new one (new rim?). To be honest at that point I
was a bit miffed and not listening attentively. Because of
my injury I can't ride it for a few weeks anyway, so it'll
do no harm sending the wheel back to Trek. If they say there
was nothing wrong with it, and I have to buy a new rim and
have it rebuilt, it won't be the end of the world, I guess
I'll just learn to appreciate that wheels can be fragile,
and approach kerbs with more caution in future.

Cheers, Roger

"]news:[email hidden]... [snip]

Quoted message said:

In the situation you have described the wheel isn't being
used in any 'normal' manner of riding, including
competition riding, and is almost definitely unlikely to
be covered by any potential warranty.

If I was taking about mounting a full kerb, then maybe I'd
agree, but I'm talking about the bit where the pavement
ramps down to the road, I mean, it's almost dead level with
the road. I've never before felt I shouldn't ride up or down
these on a bike, (well perhaps other than normally one
wouldn't be on the pavement anyway, but I was outside my own
house...) so if this is really not 'normal' riding, then
perhaps they should give some sort of warning to new riders?

Quoted message said:

PS Get well soon .. 😉

Thanks!

Roger

Quoted message said:

Riding up a kerb is a big no-no .. especially on a cycle.
If you kit a

kerb

Quoted message said:

square, or nearly square on, then you can sometimes get
away with it, but more often than not you'll hit at an
angle, as you describe, and the tyre simply won't be able
to grip enough to go over the kerb, so 'slips off'
sideways, probably buckling the wheel - this sounds
exactly what you've done. Whenever I go up a kerb I lean
way back and lift the front wheel

up,

Quoted message said:

then bunny-hop the rear over the lip, as though it's a
jump lip .. I

rarely

Quoted message said:

do this at a very (nearly parallel you said) oblique
angle, unless I'm

doing

Quoted message said:

a full bunny-hop, the tyres simply can't cope .. and
neither can _any_

wheel

No it's not.

A well built wheel with a decent rim will laugh off curbs. I
use Mavic 517 (or their modern equivalent) rims and double
butted SS spokes. I then bash them about over sticks and
stones, perpendicular and at oblique angles.

I agree that you need to engage in weight transfer - but for
a 1" curb?

John

paul said:

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

They looked at me with disbelief, shrugged and said the
only other thing they could do was send it back to Trek
for analysis and see what Trek had to say, so I agreed
to that.

IANAL but Sale of goods act is your friend. You bought an
ATB/MTB whatever, and you can therefore reasonably expectg
it to cope with 2cm bumbs in the road, no matter that it
was a droped kerb, nor what angle you hit it at. The wheel
was NOT fit for purpose, Wheels are meant to be round,
yours isn't any more, ergo it failed under conditions that
could reasonalbe be expected to be encountered.

I think it's more likely that the wheel bent from having a
sudden sideways load applied than from hitting the kerb. I
don't think there's any evidence that it wasn't fit for
its purpose.

--
Dave...

Get a bicycle. You will not regret it. If you live. -
Mark Twain

paul said:

You bought an ATB/MTB whatever, and you can therefore
reasonably expectg it to cope with 2cm bumbs in the road,
no matter that it was a droped kerb, nor what angle you
hit it at.

You might expect the wheel not to buckle as it hits a 2 cm
bump what kind of magic can it have to prevent the rider
crashing when he does something stupid? The wheel could have
buckled after the initial impact. The wheel wasn't
responsible for the crash. The crash could have happened
with ANY wheel. You can not reasonably expect an MTB wheel
to survive all 20 mph crashes.

~PB

Roja Doja said:

"]news:[email hidden]... [snip]

Quoted message said:

In the situation you have described the wheel isn't being
used in any 'normal' manner of riding, including
competition riding, and is almost definitely unlikely to
be covered by any potential warranty.

If I was taking about mounting a full kerb, then maybe
I'd agree, but I'm talking about the bit where the
pavement ramps down to the road, I mean, it's almost dead
level with the road. I've never before felt I shouldn't
ride up or down these on a bike, (well perhaps other than
normally one wouldn't be on the pavement anyway, but I
was outside my own house...) so if this is really not
'normal' riding, then perhaps they should give some sort
of warning to new riders?

Dropped kerbs can be badly aligned. You described it being
up to an inch high, which I reckon's too much for mounting
at an oblique angle. If meant for cycling up (i.e. you were
joining a cycle path on the pavement) then I'd consider a
complaint to the council.

I wouldn't ever attempt to ride up such a high kerb at
20mph.

Simon

Roja Doja said:

If I was taking about mounting a full kerb, then maybe
I'd agree, but I'm talking about the bit where the
pavement ramps down to the road, I mean, it's almost dead
level with the road. I've never before felt I shouldn't
ride up or down these on a bike, (well perhaps other than
normally one wouldn't be on the pavement anyway, but I
was outside my own house...) so if this is really not
'normal' riding, then perhaps they should give some sort
of warning to new riders?

I'm with you Roja, riding up the dropped part of the kerb
that you described (1.5 - 2.5cm) really isn't dangerous at
all IMHO. It certainly shouldn't be enough of a hazard to
threaten the integrity of your front wheel. I'm a pretty
hefty bloke myself and I often clatter up and down kerbs.
This is full kerbs too, not just dropped sections, and I
have no trouble. Granted I don't do this when out on my
"best" bike, delicate wheels and all that, but on either of
the hacks I don't give it a second thought.

The point that has been made about being careful when
tackling the kerb at a shallow angle is valid, but as long
as you are aware of the danger this shouldn't cause a
problem. Unweight each wheel as it passes over the kerb and
be positive in your steering. You can improve the angle of
"attack" without needing to sweep out and ride full on at 90
degrees - just a small lean and swerve at the appropriate
(last!) moment will help a lot.

You said you went over the handlebars which means the bike
must have stopped pretty darned sharpish. This isn't what
would happen if you'd just buggered up mounting the kerb at
a narrow angle. If it had been that then your front wheel
would have slipped sideways along the edge of the kerb and
your balance would have been thrown off line. You'd have
gone down more sideways onto the kerb than over the bars.

Given how you described the incident I'm at a loss to
understand how the wheel was buckled so badly.

As Pete said, hope the elbow heals fast and you can get back
to riding soon.

Chin up 🙂
--

"Bob"

'The people have spoken, the [censored]'

Email address is spam trapped. To reply directly remove
the beverage.

Roja Doja said:

Quoted message said:

Quoted message said:

I hit the kerb between pavement and road where the
pavement ramps down to the road, so the kerb was not
more than 2 or 3 cm high.

Can you go back and measure the exact height to check?

As it's just outside, yes! It varies between about 1.5 to
2.5 cm (which seems almost nothing kerb-wise)

I agree that's pretty shallow (I wouldn't normally expect
that to damage a wheel) but 20 mph was a bit fast for it.

Quoted message said:

Quoted message said:

Quoted message said:

It was at quite an oblique angle (i.e. I went up the
kerb almost parallel to it , not straight at it) and I
was doing about 20mph or less. Should this cause a MTB
wheel to fail?

First of all, regardless of wheel strength, it's really
dangerous to go up a kerb at an oblique angle, full stop.
You can loose control all too easily, as you've found.
Always take any kerbs straight on and at low speed,
easing your weight off the wheels.

Easy if you're crossing a road, but I guess if you're
coming off a busy road, you can't really pull out into the
middle of the road so you can turn towards the kerb straight-
on can you?

Just out to the middle of the inside lane would do if
speed is low enough. I do it all the time. If you can't do
that, yes, get off the bike! ...or stop and lift front
wheel up, etc.

Quoted message said:

At least I've never seen anyone attempt that! Perhaps I
should've pulled over and got off, then lifted the bike
onto the pavement, maybe if I had a race bike with super
skinny wheels I'd have been more inclined to do that, but
I assumed it wouldn't be a problem riding a mountain bike
with bit fat tyres, it's never been a problem before. My
arm tells me I was wrong though!

Perhaps the rock-hard tyre pressures and aluminium frame
make the new bike more of a precision-machine, and maybe
it's more unforgiving than the [censored] old bikes with half-
inflated tyres I was used to riding.

Hard tyres actually protect the rim in the worst impacts
(because they don't compress all the way to rim), hence you
didn't get a dent, but wider softer tyres will increase grip
and traction at least.

Quoted message said:

Quoted message said:

Another very real possibility (especially if no distinct
dent in rim) is that you lost control because of the
oblique angle and the wheel buckled *after* the initial
impact. That would definitely be entirely your fault.

I'd concede this is a possibility, I'm just not sure how
my losing control and then falling off could cause the
wheel to buckle? The bike didn't hit anything, I had my
hands on the handlebars, it just kind of wobbled, stopped,
I went over, the bike tipped over and then hit the ground.
Without my weight on it, I'd have thought that was even
less likely to be the cause of wheel buckling?

Your weight might have been on it for a moment but all
sorts of crashes and falls can result in a buckled a
wheel. Just the bike's own weight even just the wheel's
weight can be enough if impact with object/ground is fast
or awkward enough.

Frankly, I don't know how wheels get buckled *exactly*.
It's a highly technical subject, but I know there's a lot
of luck involved. Perhaps the wheel would have survived in
another incident just like it if only one variable was
slightly different: maybe just 0.2mph different, 1 degree
different, etc. I've survived some massive impacts with no
damage at all, yet had rims written off by what seemed like
a minor bump.

As I mentioned, the wheel could have been built poorly but
that's virtually impossible to prove now. Wheels with
optimum spoke tension survive this kind of thing better,
even with super-light rims.

You could try the rec.bicycles.tech newsgroup. Jobst Brandt,
author of the world famous The Bicycle Wheel book, will
answer with a bit of luck (if he's not away on holiday).
Plenty of other wheel experts there as well. But don't
expect any sympathy there: they're a hard bunch! :-)

~PB

Roja Doja said:

Quoted message said:

Another very real possibility (especially if no distinct
dent in rim) is that you lost control because of the
oblique angle and the wheel buckled *after* the initial
impact. That would definitely be entirely your fault.

I'd concede this is a possibility, I'm just not sure how my
losing control and then falling off could cause the wheel
to buckle? The bike didn't hit anything, I had my hands on
the handlebars, it just kind of wobbled, stopped, I went
over, the bike tipped over and then hit the ground. Without
my weight on it, I'd have thought that was even less likely
to be the cause of wheel buckling?

Bicycle wheels are amazingly strong for their weight, but
only in one plane. Even the best wheels are not designed
to withstand large side loads. From your description of
the accident I think the most likely explanation is that
you lost control from mounting the kerb and the steering
turned enough that the wheel stopped rotating. This could
easily have been enough both to buckle it and to throw you
over the top.

Quoted message said:

Quoted message said:

Anyway, hope the injury heals quickly (that's more
important).

Seconded. When you're riding again you should either take
kerbs (gently) at 90 degrees, or for real street cred learn
to bunny hop onto them. As others have said you do not need
a complete new wheel, just a rim. The spokes can be safely
re-used except for any that have got kinks in them.

--
Dave...

Get a bicycle. You will not regret it. If you live. -
Mark Twain

Roja Doja said:

"Pete Biggs" <[email hidden]> wrote in
message "]news:[email hidden]...

Quoted message said:

Roja Doja wrote: ..............

Quoted message said:

I hit the kerb between pavement and road where the
pavement ramps down to the road, so the kerb was not
more than 2 or 3 cm high.

Can you go back and measure the exact height to check?

As it's just outside, yes! It varies between about 1.5 to
2.5 cm (which seems almost nothing kerb-wise)

Quoted message said:

Quoted message said:

It was at quite an oblique angle (i.e. I went up the
kerb almost parallel to it , not straight at it) and I
was doing about 20mph or less. Should this cause a MTB
wheel to fail?

I'm bemused by your accident too. I would have thought you
would be more likely to fall sideways to the left - not over
the handlebars.

Two questions: how tightly were you holding the handlebars?
And did you have mudguards fitted?

I wonder whether the kerb could have caused the handlebars
to twist rapidly sideways. If the front wheel was pointing
sideways then I can see how it might have failed. But I
still think you would have fallen sideways before any damage
could be done to the bike.

I once had an accident where my front mudguard came loose
and caught in the front wheel. The damage was spectacular
even though I was not going fast - the tyre was bunched up
against the mudguard and the valve torn from the inner tube;
the front wheel ended up looking like a pringle. The bike
cartwheeled, landing on (and smashing) the saddle.

As an aside, I was so dazed it took me a few minutes to
work out what had happened. An elderly couple on the other
side of the road were convinced I'd had a seizure and
cycled into a lamp-post next to where I fell. Even though
I didn't hit my head I half-believed them for a while. It
must have looked like I cycled into an invisible brick-
wall - interesting how we can make up stories to explain
what we see.

Quoted message said:

Quoted message said:

First of all, regardless of wheel strength, it's really
dangerous to go up a kerb at an oblique angle, full stop.
You can loose control all too easily, as you've found.
Always take any kerbs straight on and at low speed,
easing your weight off the wheels.

Easy if you're crossing a road, but I guess if you're
coming off a busy road, you can't really pull out into the
middle of the road so you can turn towards the kerb straight-
on can you?

Cars turning right often hold up the traffic whilst they're
waiting for the other side of the road to be clear. If
you've got to, then do...

Assuming your normal cycling distance is about a meter from
the kerb, you should be able to turn so the front wheel
crosses the kerb at 45 degrees and slow down a bit - which
IMO should be fine.

Quoted message said:

At least I've never seen anyone attempt that! Perhaps I
should've pulled over and got off, then lifted the bike
onto the pavement, maybe if I had a race bike with super
skinny wheels I'd have been more inclined to do that, but
I assumed it wouldn't be a problem riding a mountain bike
with bit fat tyres, it's never been a problem before. My
arm tells me I was wrong though!

I'm glad to hear the rest of you survived. I hope you have a
speedy recovery.

Quoted message said:

Quoted message said:

Note: Wheel can be rebuilt using existing hub and
spokes. Don't need a whole new wheel.

Yes, I guess that was what they meant when they talked
about a buying a new one (new rim?).

It might pay to check the hub before getting the wheel
rebuilt. The flanges (that hold the spokes) might have
cracked, and check the axle moves smoothly.

AC

Pete Biggs said:

paul said:

You bought an ATB/MTB whatever, and you can therefore
reasonably expectg it to cope with 2cm bumbs in the road,
no matter that it was a droped kerb, nor what angle you
hit it at.

You might expect the wheel not to buckle as it hits a 2 cm
bump what kind of magic can it have to prevent the rider
crashing when he does something stupid? The wheel could
have buckled after the initial impact. The wheel wasn't
responsible for the crash. The crash could have happened
with ANY wheel. You can not reasonably expect an MTB wheel
to survive all 20 mph crashes.

So you mean when I'm bombing down a local lane at 20mph I
ought to be expecting my front wheel to fold up? It's a
mountain bike wheel for christ's sake.

"Simon Proven" wrote: [snip]

Quoted message said:

Dropped kerbs can be badly aligned. You described it being
up to an inch high, which I reckon's too much for mounting
at an oblique angle. If meant for cycling up (i.e. you
were joining a cycle path on the pavement) then I'd
consider a complaint to the council.

I wouldn't ever attempt to ride up such a high kerb
at 20mph.

Fair enough, given opinion so far, I forsee I won't be
attempting to ride up dropped kerbs again.

I don't think I'd like to actually put the bike to its
supposed use then, and ride it down a mountain, if a 1.5cm-
2.5cm lip is enough to cause problems?

Roger

"Pete Biggs" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

You could try the rec.bicycles.tech newsgroup. Jobst
Brandt, author of the world famous The Bicycle Wheel book,
will answer with a bit of luck (if he's not away on
holiday). Plenty of other wheel experts there as well. But
don't expect any sympathy there: they're a hard bunch! :-)

It's not so much that they are a hard bunch as that the
group has dealt with a lot of the same questions a few
thousand times, so posts like "I though about wheels and it
seems to me that the hub hangs from the top spokes really"
tend to get a somewhat short response.

I've only been reading it since 1993 (it's older than that
IIRR) and I can't tell you how many times the "grease/don't
grease the crank tapers to install" argument has been
covered :-)
--

-- M.