Mountain Bike Reviews Forum banner
1 - 18 of 18 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #1 ·
Hi everyone,

I recently discovered a dent in my rear rim. I am running tubeless and am wanting to know the best approach to fix the dent. I believe I can bend it back using a wrench and a flat metal surface against the rim (taking precaution).

Thanks
1945510
1945511
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #2 ·
UPDATE: I’m also limited on tools as New Zealand is currently in covid lockdown. Also, if I want to top up the tubeless sealant, can I add to the exisiting sealant that’s in there? The current sealant is only 7-8 months old

cheers
James
 

·
Registered
ya like dags?
Joined
·
5,889 Posts
I can't believe that's holding air. You could try to bend it back but I don't know... Looks like it's creased from the pic and may break the rim. You may be looking at a new rim (that's what I'd do personally).

For sealant, just top it off. Orange seal has a dipstick that comes with their bottles, but honestly I just add more regardless of how much is in there. 4oz extra isn't going to hurt if there's already some in there.
 

·
Big M, Little organ.
Joined
·
295 Posts
Honestly, I’ve had several rims in that condition and I’ve taken a crescent wrench and a rubber inner tube for padding and bent the lip right back. Now, you may have a slight flat spot or need to true the rim up afterward but I’ve ridden the “repaired” rims for hundreds of miles afterwards.
I would think about tire inserts though!
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #7 ·
Thanks everyone! I really appreciate it! I’m relatively new to mtb and so if I am to get a new rim, does anyone have any suggestions to a fair priced rim that will fit my 2021 Trek Fuel Ex 7 (or what I should be looking for in a rim) Funny enough I actually buckled my front wheel earlier this year and a replacement stock bontrager rim was $250 (NZ dollars). And should I be considering CushCore for it?

thanks!
 

·
Registered
Joined
·
2,358 Posts
I'd bend it back with an adjustable wrench. I don't even bother trying to protect the rim with rubber. Worst case you can put a tube in it.
Well worst case you bend it enough and it breaks. But that's the beauty of aluminium, it'll go back and forth a bit before it breaks. If you're getting rim strikes a bit then keep an eye on your tyre pressure, it may need to go up a bit.
 

·
Registered
Joined
·
3,555 Posts
If you see stress fracturing (like you have--the little silver spider-web marks) it's likely that trying to bend it back will result in the metal tearing.

If the rim is holding air, running straight, and the spokes are still holding good tension, place a new wheel/rim (depending on your mechanical ability) on order, and keep riding until it comes in. Rims are an economical way to repair damaged wheels, especially if you are replacing like-for-like; simply tape the two rims together in the same orientation, and move the spokes, one side at a time (all left, all right, whichever is closer to the new rim first).

If the tire is still holding air with the damage to the rim sidewall, you can break the other side (if undamaged) to check on the sealant levels, but I would--again--leave the other side alone/mounted until you have a replacement in hand.
 

·
Big M, Little organ.
Joined
·
295 Posts
Thanks everyone! I really appreciate it! I'm relatively new to mtb and so if I am to get a new rim, does anyone have any suggestions to a fair priced rim that will fit my 2021 Trek Fuel Ex 7 (or what I should be looking for in a rim) Funny enough I actually buckled my front wheel earlier this year and a replacement stock bontrager rim was $250 (NZ dollars). And should I be considering CushCore for it?

thanks!
[/QUOTE
If you are bending rims often either you run too little air or you need an insert. Which insert is "best" for you depends. Lots of other threads on that topic. I've run several and the vittoria airliner is a good compromise IMO. Good protection, fairly light, easy to install. Not the best/lightest/easiest but a good option.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #11 ·
Thanks all. Tbh my pressure was really low so that's why it would have bent (lesson learnt!)
Does anyone know if I can simply purchase a new rim and then attach the rest of the wheel's parts?

was looking at this rim here


Or

 

·
Registered
Joined
·
1,595 Posts
each rim has its own specific inner diameter. this means the spoke
lengths change from one rim to another. if you pick the wrong relacement you could end up w having to buy spokes.
some rims are asymetric so they will definitely need new spokes.

you might need nipples too.

id get a new bontrager rim. change like for like

but why are they breaking/bending

you trying to be danny mac?

please explain your use. rims only bend when big mistakes are made or from abuse.
 

·
Elitest thrill junkie
Joined
·
41,057 Posts
This looks like toast. This is not a minor bend. Bending it back that far with the signs of tension fractures/tears already present will likely result in a fracture. If it was just that smaller dent, maybe. I've also seen dents like this chew through the tire sidewall where it meets the bead.
 

·
Pro Coffee Drinker
Joined
·
272 Posts
I'm in the bend it back camp. That's a bad knock, so don't go for perfect. Just get it half way there nd call it good. Also run more air.
Be ready to buy a new rim, but you should do with this gentleman suggested. Do not try to get it back to straight or you'll likely end up cracking the rim. Either way you should be looking for a new hoop.

Get out your adjustable wrench and carefully adjust it so that the flange of the rim isn't facing inward toward the tire. I've bent my rims back into shape several times using a C-Clamp and a small piece of aluminum, as well as an adjustable wrench and mechanic's hammer, but they've never been that bad.

-DS
 

·
Registered
Joined
·
1,801 Posts
Thats bad, if its holding air, I'd leave it alone until you get replacement rim/wheel. With disc brakes, if its holding air, there isn't too much reason to mess with it until you need to change tire. Although I'm amazed its not leaking. The degree that is bent, there a good chance the metal will crack when bending back. Aluminum doesn't like to be bent much. If its leaking, then you could try bending back enough that the bead is relatively smooth. Being an ex trials rider, I have bent back my share of dented rims, but this is back inthe tube days.
 

·
Registered
Joined
·
794 Posts
Thats bad, if its holding air, I'd leave it alone until you get replacement rim/wheel. With disc brakes, if its holding air, there isn't too much reason to mess with it until you need to change tire. Although I'm amazed its not leaking. The degree that is bent, there a good chance the metal will crack when bending back. Aluminum doesn't like to be bent much. If its leaking, then you could try bending back enough that the bead is relatively smooth. Being an ex trials rider, I have bent back my share of dented rims, but this is back inthe tube days.
Safety on bikes is paramount cause it can kill you, get a brand new wheel and don’t look back. Your life depends on that wheel. Dump it and never ride a bike that is defective. Off seasoning I would repair but during riding season I would just go get a rim ready to go.
 
1 - 18 of 18 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top