Still debating upgrading or replacing a 9 year old Superfly.
It doesn't get used as a full blooded MTB so geometry/ features etc. are fine, in fact for my purposes it's almost better than a new frame as I don't want slack head angles or 1x only etc.
But it's 9 years old! It's had an easy life right enough, only ~5000km in that time, much of which was tarmac commuting and the rest of which was basically 'rough gravel' rather than anything seriously rough.
What can you measure frame lifespan in? I would run it into the ground but don't want to spend e.g. £500 on new wheels which would be obsolete due to 135mm OLD etc. etc.
The EN frame tests are 50k or 100k cycles at very high load - tests designed to break frames by upping the load to reduce cycles to failure.
If you've ridden it ~5000km those tests would be 10 or 20 of those loads PER KM. OC there's all the smaller real-world riding impacts between those theoretical loads and it all adds up but still - it would be very heavy use to fatigue a frame in 5,000, even 10,000km. And frames are specced to pass the test, not break at that 50/100k cycle point. Your bike has a long life ahead of it at the current rate of use.
My current aluminium 29er hardtail is a fisher from 2006. I got it around 2015 and it's been used regularly since, currently in 'do everything bike' mode. The forks are probably the same vintage as well, a set of gen 1 29er rebas!
The EN frame tests are 50k or 100k cycles at very high load - tests designed to break frames by upping the load to reduce cycles to failure.
If you've ridden it ~5000km that would be 10 or 20 of those loads PER KM. OC there's all the smaller real-world riding impacts between those theoretical loads and it all adds up but still - it would be very heavy use to fatigue a frame in 5,000, even 10,000km. Your bike has a long life ahead of it at the current rate of use.
Awesome, I was kind of hoping you might respond to this one!
Although... if my maths is correct, is 5000km * 20 loads not 100,000 loads? i.e. the upper end of those frame tests you mention? Is that a typo or am I misunderstanding?
But yeah, if lifespan is measured in impacts rather than e.g. pedalling stresses or ride weight (sadly power isn't the relevant factor here 🙄) then yeah, I've got many happy years left!
What can you measure frame lifespan in?
Another more cynical answer - the age or shabbiness where the manufacturer declines a Limited Lifetime Warranty.
The forks are probably the same vintage as well, a set of gen 1 29er rebas!
Yeah I'm sort of taking pleasure in getting the forks serviced yearly now (Pedals @ Dunfermline). I swear they feel better now than they did as stock.
I've a OnOne Scandal 29er that i bought in 2011 for £220 (found the receipt the other day!): it's done 13k miles according to Strava so probably more than that too...not bad for a bike that gets all the winter grind. Genuinely impressed it's hung in there as the seat stays are pencil thin for alloy down near the dropouts. Plus I've never exactly been delicate on it.
Also got a Klein Attitude from pre-2000...thats fine too albeit didn't get used as much
Cable wear.
It's OK, the cables are just gradually sawing their way through the fork crown, the frame is fine 🤣
Technically an aluminium frame is measured in all of the above, as there is no real lower fatigue limit. In reality, unless it's a proper superlight aluminium race frame, or built with some really questionable features, it's pretty much academic.But yeah, if lifespan is measured in impacts rather than e.g. pedalling stresses or ride weight (sadly power isn't the relevant factor here
) then yeah, I've got many happy years left!
Although... if my maths is correct, is 5000km * 20 loads not 100,000 loads? i.e. the upper end of those frame tests you mention? Is that a typo or am I misunderstanding?
Well 'fwiw', as I'm not a qualified engineer. I meant 10 or 20 of those load cycles per Km to equal the tests which are 50k or 100k cycles depending on the tests. So yes, 5,000km at 20 loads per km equals the cycles of the 100k test/s, others for MTB are 50k cycles.
And edit to add, as Mert says, impacts, pedal loads, fork leverage, trail chatter vibrations, it's all loading that adds to fatigue. The tests just repeat certain types of load to give a benchmark.
My Orange Gringo, bought for me for my fortieth is still going strong despite Peak District/Lake District/North Wales rock bashing.
I’m sixty-six soon!
Oh I see, as in 'I would have to be inflicting 10 or 20 of those cycles per km to equal the tests' 👍
Since you've piqued my curiosity now, what does a single load cycle look like? Is it a bending load or an impact of some sort?
Either way am sufficiently reassured, shall upgrade rather than replace 😎
Yeah I'm sort of taking pleasure in getting the forks serviced yearly now (Pedals @ Dunfermline). I swear they feel better now than they did as stock.
In my experience, any suspension fork feels better after I've serviced it - even from new.
Since you've piqued my curiosity now, what does a single load cycle look like? Is it a bending load or an impact of some sort?
There's a few tests and you might be able to find EN4210 online as a copy, or an older version that covers the majority of the current tests. Pedal fatigue test is 1200N per pedal per cycle, x 100,000. Horizontal fatigue uses a fork as a lever, 600N back and 1200N forward x 50,000 for MTBs. Both are static bending loads. There are impact tests also.
I had 15 years out of an aluminium cove stiffee. Ridden and smacked about most weeks.
Superfly is going to be built for weight not smacking about, but unless it was visibly failing or I had had a lot of very hard cases it continue riding it.
I'm off out on my aluminium road bike tonight. I've had it 10 years and it was second hand to me. I think it had been ridden, found to be hard work and put in a garage. It's from 2013 so 13 years old.
It's a bit powdery round some of the bosses but otherwise in decent condition.
For general scooting around and commuting it will probably live forever.
Would i buy an old one. No
Would I continue with one I owned for a long time. Likely.
Would I nip off and do your divide on it. Also no.
It used to be the case that my aluminium frames (including two Fishers and a Klein Attitude) would let you know by kindly cracking at the BB welds, usually within the two year mark. The 2011 Rockhopper I've been running for the last six years seems to be made of sterner stuff and I'll happily keep using it.
