Why do the rims on my Specialized Mountain bike keep bending?

Question

I have recently purchased a Specialized P.2 Mountain bike, the rims appear very bendable, and they become bent or out of true very easily. Could anyone shed some light on why i can take a sledge hammer to my BMX rims and they will still be next to perfect. Yet i land a bit sideways on a 180 or 360 and my P.2 rims get all messed up.

Answer 1

larger diameter and lighter metals used in mking them they are designed for speed and agility not hardcore bashing, check your spokes to see if they are all tight, you should check them weekly.

Answer 2

They use a sigle wall rim...lighter, but not strong.  You should upgrade to a double wall freeride wheelset....(Sun Rims singletrack or Doubletrack, Mavic 328...etc..)

Answer 3

"A bit sideways on a 180 or 360...."    Dude, that's most of what you need to know right there!  lol    :o)

Lateral loads on a wheel are the hardest thing you can do.....even very strong 26" wheels will tweak or fail when you take a hit like that.  I've bent up a Halo Combat that way, and that wheel has seen many 4' to 6' drops onto flat concrete without any trouble.   So your answer is probably to get a really strong wheel and try to land the tricks a little better.  

Mavic doesn't make anything really good for that kind of abuse....the Deetrax/Deemax rim is ok, but there are better ones for less money.  Choose a good rim and build it proper and tight and it'll do its best for you.   These are ones I'd consider if I were you:  Halo SAS, Transition Revolution, Atomlab GI Dirt, Sun Doubletrack, Alex DP(DH?)32, and maybe even an Echo 40mm rear trials rim (super neato strong!).   Spank has some bomber rims out now, too, but they're hard to find.  

You want to look for a rim that's at least 32mm wide....more is better.  For a rear wheel, I personally won't use anything less than 36mm on my abused bikes.....I've bent up too many lesser rims including a few Rhinolytes (29mm).  

Choose a 48 spoke setup if you don't mind buying a new hub....you can order a Halo SAS 48h rear wheel for not too much money.   The 48h wheel will hold up to alot more abuse from lateral loads.   At the least, you want 36h.   Also, you should really consider a solid axle if you don't already have one.

For the front wheel, you can usually get away with less bulk.  I run a Halo Tornado 32h (32mm) on the front right now and it's doing great....even the cartridge bearings are holding up.  But for the rear wheel....go all out, man.  Get something durable and don't worry too much about the extra weight.

Hope this helps....and don't knock the Specialized wheel the bike came with...you're just giving it alot more workout than it was designed for.   I don't know if they build up their own wheels or have it done for them, but every Specialized wheel I've ever come across has been well-built and dependable.

If you need any more help, post up again.  Good luck!   :o)