How to fix a dented MTB rim?

[Clinton - theCOW]

After hitting enough rocks, my MTB rims have a few dings in them, i was wondering how to get them kinda straighter, even tho i don't have any issues with them sealing at the moment.

 

So started googling, seems quite simple, going to try it since the tyres are off for maintenance, need to get the wheels ready for this weekend

 

http://www.pinkbike.com/news/Tech-Tuesday-Fixing-Rim-Dents-2012.html

http://www.bicycling.com/maintenance/repair-maintenance/bike-repair-dented-rim

 

Then i came across this interesting book as well

http://books.google.fr/books?id=KbtiuIhNTcAC&pg=PA65&lpg=PA65&dq=how+to+fix+a+dented+mountain+bike+rim&source=bl&ots=TpnwmWlk7e&sig=2rcsVDr6Na0gx1kGQkMuOk1is0U&hl=en&sa=X&ei=a5T8Ur3KIOSR7Aaj94GwBA&ved=0CDsQ6AEwAg#v=onepage&q=how%20to%20fix%20a%20dented%20mountain%20bike%20rim&f=false

[Headshot]

The shifting spanner works a treat -if done carefully you can dispense with the metal tyre lever they talk about. Did my back rim yesterday evening.

[RuanJvR89]

This works. Done it before.

[Super_mil]

Here is a topic from sometime back, when JB used to respond on the Hub.

 

1) https://community.bikehub.co.za/topic/128757-how-to-remove-dents-from-rims/

2) https://community.bikehub.co.za/topic/81195-dented-tubeless-mtb-wheel-what-to-do/

 

Consensus seems to be not to bend them out using a spanner as you further fatigue the metal. Rather hammer the dent out.

[rouxtjie]

Crintons....

 

running straight is a truing issue...but dents stopping you from sealing tubeless systems can be straightened...like other said, shifting with a piece of rag. Note though that every time you bend, you weaken the spot so don't go back and forth so to speak. The softer the material the easier it is to straighten but also the easier to dent...AM classics vs ZTR rim as an example

[Clinton - theCOW]

I remembered a thread about "hammering" it straight, just couldn't find it.

 

Wheels are sealing, so happy either way, just wanted to try straightening while the whole lot was apart.

 

Trueing is something i'm aware of, just tyres sometimes don't seat 100% straight either

[V12man]

 

just tyres sometimes don't seat 100% straight either

 

Sometimes that is because you don't add enough pressure in the initial sealing - more air usually gets them straight - useful to have a compressor to do this...

 

If you want hands to help do it sometime - pm me - my 2c for your choc efforts - 10 min ride from choc.

[Clinton - theCOW]

Thanks for the offer, the lil lady has a compressor i pump to the max pressure a stans crest will allow with a foot pump, the tyre normally "pops" into place.

 

I've had a stans shower before, no so pleasant breaching the max pressure barrier.

 

I can live with a marginal wobble, not toooo OCD

[RobynE]

Thread revival! 
 

I have AM Classic MTBRace rims and the front had superficial dents from when I bought the bike. 
 

I recently changed tyres and had the wheel trued, and in doing so hoped that the wheel would run more straight. It does, marginally, but it’s still not straight. I feel it on tar but not on hard pack or trails. But the feeling on tar is really irritating me 😂 It probably shouldn’t, but it does. I feel like it slows my roll. Smooth-bump-smooth-bump and the bump is enough that my handlebars bump too. My other bike doesn’t have any bumps at all so it’s super noticeable for me on my MTB. 
 

When I have the bike in the service stand I can see how much it moves. It also has a recurring “mouse” in the rotor as it moves quite a bit between the caliper. I’d say the movement is probably close to 1cm though I haven’t measured exactly. 
 

I know the wheels are very light so while I am looking for one new one, I am wondering if maybe I should change rims to something else. But I really love the look and feel of these rims so I guess my question is: 

 

Would you do the best you can with the rims, or look at changing, and if changing from AM Classic MTBRace, what would be a sturdier but similar rim that won’t be super expensive? 
 

Or is there someone who can really straighten out the existing rim so that it runs true without bumps and I get to keep it? 

[RobertWhitehead]

1 hour ago, RobynE said:

 

😂

I wouldn't say a cm but rather a mm . But back to the wheels: They're American Classic and the hoops are light but also quite soft, so the risk will be to either crack the rims around where the nipples sit or pull the nipples through the rims completely. If a light set of wheels are the only determining factor then I can help 

[droo]

Sound more like a flat spot or out of round than a dent to me.

If whoever trued your wheels is decent he should have been able to pull it round, but if there's a flat spot it's pretty much toast. Same as if it's got a buckle rather than just wonky tension - you can only pull a minor bend straight with spoke tension.

[RobynE]

26 minutes ago, droo said:

Same as if it's got a buckle rather than just wonky tension - you can only pull a minor bend straight with spoke tension.

I think the tension is fine so I think it is a buckle or flat spot. 
 

@RobertWhitehead in fairness it’s not a cm (feels like it lol) but measuring the gap between tyre tread and mudguard now as I rotate the wheel, the variance is between 1 and 3.5mm. It stays true for probably 95% of the rotation and then dips for a period. 

[nick_the_wheelbuilder]

Sounds like your rim has a flat spot, which is practically impossible to remedy.

Unfortunately the AMC rims of that era are very soft, and ding and dent very easily.

The long term solution is new rims.

Arch Mk4 rims are 28mm inner width and 491g per rim - a super combination of width, durability and light-enough weight.

For reference, the lightest 29er rims available now are Crest Mk4, which are 25mm inner and 399g per rim.