That's pretty crazy. I hear all about the cracked MKIII frames and I haven't had a single problem with mine. I ride pretty rocky and rooty trails, I'm 6'4", and a little over 200 lbs. Freakin' love that bike! It has possesed me to get a 7 point frame...
That's pretty crazy. I hear all about the cracked MKIII frames and I haven't had a single problem with mine. I ride pretty rocky and rooty trails, I'm 6'4", and a little over 200 lbs. Freakin' love that bike! It has possesed me to get a 7 point frame...
Well, your bike is a sample size of one. Even if 40% of all frames cracked, which would be a HUGE number, chances would still be (60%) that yours would not.
Well, your bike is a sample size of one. Even if 40% of all frames cracked, which would be a HUGE number, chances would still be (60%) that yours would not.
Very true, plus people tend to talk about things when they are bad or wrong. So you don't hear about all of the positives as much. Like the fact that it's an awesome trail bike with spot on geometry... I've been very impressed with Iron Horse, even compared to "higher end" bike companies.
Actually, you will hear the good, but not in threads about them cracking. I have loads good to say about mine. So far it is the best performing frame I have owned.
That's pretty crazy. I hear all about the cracked MKIII frames and I haven't had a single problem with mine. I ride pretty rocky and rooty trails, I'm 6'4", and a little over 200 lbs. Freakin' love that bike!
Ummm, nothing special. It was just a standard steel rear skewer, don't even know the brand... I'm running a set of Single Track rims with Shimano hubs and 2.10" Nevegals. Seems to be the perfect setup for the Pacific Northwest style of riding.
Can I add to this thread... I've got a theory that the crack comes from having poorly secured rear wheels. I know a few times when the crack had begun in mine, my rear QR skewer was quite loosely secured because of compression in a plastic part of it.
I also know on my friend's bike's their stock factory through bolt style skewers come open by themselves all the time, so maybe this is a contributing factor?
I've now converted to an RWS, so the back should always be solid.
So maybe can we add whether we're running stock skewers, or having securing problems on the back?
Can I add to this thread... I've got a theory that the crack comes from having poorly secured rear wheels. I know a few times when the crack had begun in mine, my rear QR skewer was quite loosely secured because of compression in a plastic part of it.
I also know on my friend's bike's their stock factory through bolt style skewers come open by themselves all the time, so maybe this is a contributing factor?
I've now converted to an RWS, so the back should always be solid.
So maybe can we add whether we're running stock skewers, or having securing problems on the back?
I think this theory has merit, and I too think it'd be useful to find out what type of system those who've broken their MkIII swingarms are (or were) using for securing their rear wheel.
As I've stated previously, I'm using a DT Swiss RWS skewer on my MkIII. I tighten it as much as I possibly can. So far, I'm still using the original swingarm. I don't think this really proves anything yet, as I've had the bike for less than two years and my riding time has been split roughly 50/50 between the MkIII and my older 2004 Hollowpoint. (I did crack the front triangle of the Hollowpoint during that time though.) I've switched more of my riding to the MkIII now because I have spare parts for it, and none for the Hollowpoint. If my MkIII holds up for another year - I ride year-round - I'll give even more credence to this theory.
Well it's quite possible that a weak rear axle connection allows for undesired flex that causes that location to crack.
It's not really the axle's fault per se but possible that a stiffer connection mitigates the flex to a degree that reduces the crack potential.
To be more specific, I made it to about 90-100 (around a year) riding hours running a Hope Pro II rear and Salsa QR skewer with a hard (but compressible) plastic seat. So far I have a couple of months on the 10mm RWS so there isn't anything conclusive.
I know two others with 2007 MKIII's that use the standard 10mm QR's that came on them factory. They haven't had cracking problems, but they have very little ride time on them. They do have a huge problem with them loosening though, and they are both pretty light riders.
Agreed that it isn't the axles fault (although some of the stock axles seem truly horrible!), but if the axle is the solution and we can get more time out of our MKIII's then that's a good thing! I know for one I love the way mine rides.
So I'll be interested to hear everyone's input, specifically model year, details on how your wheel is secured, whether it comes loose and whether you've had the crack. From that I hope we'll be able to see a pattern.
I would say that this theory definitely has some merit. But I think there's more to it than just the rear QR. Doesn't it seem like the tightness of the entire rear end would make a difference? I mean if your hub is loose but the QR is tight, the wheel is still going to be able to move in abnormal directions which could add some weird side loads and cause a crack. Or how about all of the pivot points? Seems like if one of them is too loose that would allow the whole rear end to move around and flex. Just a thought...
One point we're all missing is that it might be hard to establish a pattern on the failures. As was alleged, when IH got cut off by one vendor, they went to another, which is why there were several frame factories going after them. Each could have introduced their own faults in the process. The sub-assemblies could have been made by other vendors, who were also traded off as IH's credit line ran out with them.
The thing is, there does appear to be a pattern. The pictures of cracked MkIII swingarms posted in this forum show the cracks to be in roughly the same location. And in fact, for swingarms of similar vintage, the cracks appear to be nearly identical.
You do make an interesting point though about IH using several frame vendors. I'll have to ponder that one for a while...
I think you have a point JC, and if we don't know the date of change over then it's going to be very hard for us to really know. However, in broader terms, if we have a bunch of 2007 frames failing, and they all had trouble with the rear wheel loosening etc then it's going to be fairly easy to see a pattern!
I'm not saying this will work, but if we can get a decent amount of data then you never know what may come out of it.
888, if your axle is tight but the hub is loose then it shouldn't really make a whole lot of difference. All hubs I've ever seen squish everything together on tightening, but the hub body is isolated from the axle by the bearings. If they're loose, the rest can still be secure.
Yes, shot bearings and loose pivots would not help, but I would think because the rear triangle is one piece then the difference may not be as much as you'd think. I'd worry if a joint with a bearing is supposed to be maintaining the structure of the rear swing arm. Although I'm sure it may not have been the first time
I still think the "survey" has merit, feel free to participate if you'd like.
Just a Hope quick release. I was thinking of adapting my Pro 2 hub to bolt-on but thought that the extra rigidity in the back end would transfer to the week spot in the rear triangle. My logic did not work. Oh well, I'll be calling RS on Monday and see what happens. Then it will be time to sell it and move on.
You know those Hopes convert really nicely to 10mm RWS, don't you?!?
It would be a really good experiment for us all, same bike and rider, different axle, could give us pretty definitive results
I've already done the conversion, so we'd double our sample size!
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