In the last 9 months I have bent beyond repair 3 KH 24" drilled rims including the 2009 model which only lasted about 3 weeks. All doing muni drops, one being less than a 1m. They all seem to bend sideways instead of bending into an ‘oval’ shape even though I’m landing forwards. I don’t think the drilled holes are really beneficial considering they reduce strength. How many people have had this happen? Are there any great 36h muni rims out there? I really like the feel of the wider rim but want something that gonna last me years. Any recommendations?
Did you retension your spokes after a few hours of riding? The spokes in new wheelsets will stretch after a few rides. If left in this detensioned state your wheelsets will be more susceptible to bending out of shape.
Interesting to hear how many you’ve gone through. The rim has been out there for 3 years now with a lot of riders doing very big moves without issue. Can you send me a couple of hires closeup photos? Send to info (at) krisholm.com.
Most of the wheel strength comes from the tension of the spokes working against the rim. The compression strength of the rim itself will not support much force at all. You may want to take the wheel to an experienced bike shop and have them properly tension it, or learn to do it yourself.
From what I’ve read about wheel building after you have retensioned the spokes on a new wheel you shouldn’t have to do it again very frequently at all. A well built wheel should stay tensioned and true for ages. You might need to do the occasional true on a muni or trials wheel as they are subject to more abuse, but hardly ever on road wheels.
There was an article on wheelbuilding in UniMag, issue five I think it was. “The Art of Wheelbuilding” by Gerd Schraner is a good reference book. Sheldon Brown’s site has a good section on wheelbuilding.
Yah. I just had it trued a few months ago and have not ridden it very much since. I haven’t really ridden it hard and it is already kinda out of true. i’m thinking I’m gonna need to get a new rim and spoke set soon.
I think that this is true in theory, but in practical terms, it’s inevitable that with aggressive freeriding the rim will end up getting out of true to a slight degree. Once it’s not perfectly true I’ve found that the rim does require regular truing to keep it functionally true, meaning that (on a muni) you can ride without ever having problems with brake rub. If you ride somewhere with a lot of big drops as part of the natural trail, carrying a spoke key on rides so that you can flip your uni over and give it a quick true right away if you screw up a drop helps a lot. So does rotating your cranks periodically, to help keep spoke tension even.
Easier said than done but it also helps the most to just get a very good internal sense for when to try hard to stick a landing, and when to just let it go, wipe out and and try again. Learning that sense, I think, determines more than anything else who tends to be light on gear or a gear destroyer.
Just for interest sake, I also have my original 05/06 38mm wide Rim. Over the years it has being buckled multiple times and I’ve trued it. It still rides fine and that’s what I’m riding muni with atm. That’s why I feel putting holes in the rim has reduced the overall strength. They only problem is that I don’t like the feel of a smaller rim for technical muni and drops.