[Bob12676]

I would swear I have seen this discussed in another thread, but a couple of searches didn't come up with anything so I thought I would ask (again maybe). I have been looking at some used DosNiner frames, '09's and '10's, and wondering if I would be setting myself up for more trouble than it's worth? I got to ride one for a few miles on my local trails and loved it, it felt as though the bike was built specifically for the type of trails I ride most often (smoothish southern Michigan single track). I have read about the frame failures, are they as likely on the newer frames as the older ones? Are there any obvious signs of wear to look for that would be a good indication that the bike has had a ton of miles put on it? This wold be a third bike and fill the gap between my carbon HT 29er and my Spearfish, so it wouldn't be an everyday bike, although it might become the favorite and get more use than the other two. Any insight would be great.

 

[DeeEight]

The risk is the same as buying any NEW pivotless softtail 6000 or 7000 series aluminium (scandium tubes are just 6000 and 7000 series alloys with the some sc thrown into the element soup of the alloy) frame would be. You never know when the fatigue crack/failure of the frame will happen, but it WILL definitely happen. I've known that for a decade plus and it still didn't stop me from buying a Dos Niner frame. With the exception of a handful of 5000 series alloys (which aren't used in bike parts/frames anyway) all aluminium alloys suffer from the same lack of a determinable fatigue load limit. Unlike steels, titanium and magnesium alloys (where if you keep the stress loads / flexing of the structure below a certain level, they'll last practically forever) with aluminium alloys, any stress load or flexing of the structure will add to number of cycles until failure.

Frame designers know this and will try and add more material/design into the frame some predictability on when the failure will come which can sometimes be reflected in how long a warranty they offer against defects in design/material/assembly. A frame that suffers a fatigue failure after 3 weeks would obviously count as defective but 6 years later...when they warranteed for say 5 years... that's not a defect of the frame, that's the natural property of the alloy.

If you're worried about a Dos frame, I have to wonder why you bought a spearfish given that they also employ the flexing of aluminium stays in lieu of a dropout pivot. The movement involved is small, smaller than the whole rear stay assembly of a Dos, but the principals that will lead to failure are the same.

 

[Bob12676]

Dee Eight, Thanks for the info. I understand that work hardening is a fact of life and that nothing lasts forever. I certainly didn't want to come off as though I was calling the Dos some sort of ticking time bomb. It's just difficult to gage the frequency of failures when poking around on the forums and I was looking for some insight. In a couple of threads I have read people saying that failure is going to happen and they post about kind of matter of factually like it happens all the time. I know the spearfish uses the same flexing stay principle but on a smaller scale (5mm or so is what I was told) so I figured less flex = longer life. I think I'm just going to get a Dos and see what happens. Like you said the warranty period should be a good indicator of life expectancy and as long as the frame I get doesn't look abused I should get a couple of years out of it. Thanks again.

 

[Hand/of/Midas]

You have a Spearfish AND a carbon HT 29er.....and want something in between?

 

[rth009]

You have a Spearfish AND a carbon HT 29er.....and want something in between?

I do not understand the world anymore.

+1. Seems to me like all the bases are covered.

 

[Schmucker]

You have a Spearfish AND a carbon HT 29er.....and want something in between?

n+1. It's why I have 12 bikes. They are all a bit different however.

 

[Bob12676]

You have a Spearfish AND a carbon HT 29er.....and want something in between?

I do have both a Spearfish and a carbon 29" Stumpjumper and I'm not really trying to fill a void. I like both bikes but I also liked the Dos I rode and to be honest it is really more of what I was looking for when I bought the Spearfish. I just wanted something to take the edge off on longer rides. The Spearfish was as close as I could find, without investing the small fortune a YBB would have cost. I have a full 1x9 XTR drive train on an old 26" bike and some extra 29" wheels and if I can pick up a nice frame for a few $, well why not?

 

[kkjellquist]

Personally I would not buy a green or orange Dos....EVERY person I know broke thiers. EVERY one.

I would buy a silver which is what I am riding now.

 

[reallylike2ride]

I had a silver 09 dos niner. It cracked at the shock mount at the end of ONE season of riding. I really liked it while it lasted. Salsa was great about the whole thing. They tried to give me a spearfish, but I asked for a el mariachi frame and fork. I don't like any suspension, so it's steel from here on out.

 

[Bob12676]

I took the plunge. I bought a large 2010 Dos that, according to the seller, was used for one season. I have to believe it got very little use, the frame is beautiful, not a scratch or chip on it. I've got a few rides on it and I really like the frame. It was a budget build, so there is some room for improvement, the 2006 Reba Race might be first to go, or maybe the rapid rise derailleur (not that it's bad, just because it shifts the opposite of my other bikes).I've got my fingers crossed that it lasts a couple of years, or more.