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Snappage.. again!!

Mr Jones

Mr Jones

Turbo Monkey
Nov 12, 2007
1,475
0
Good Stuff! As far as the breakage goes... the parts are obviously not up to your calibre.
 
w00dy

w00dy

In heaven there is no beer
Jun 18, 2004
3,417
51
that's why we drink it here
Riding lightweight parts at your level requires replacing the important stuff every couple of months. I know Mike Tag used to replace his forks a couple times a year. These things have a fatigue life.
 
Chumble spuzz

Chumble spuzz

Chimp
Apr 22, 2003
60
0
Lower VT
With respect, I don't think fatigue life has anything to do with this snappage! Dude is going big and landing hard despite being a smooth rider. Fatigue life usually isn't a concern until you approach millions of cycles.
 
w00dy

w00dy

In heaven there is no beer
Jun 18, 2004
3,417
51
that's why we drink it here
Chumble spuzz said:
With respect, I don't think fatigue life has anything to do with this snappage! Dude is going big and landing hard despite being a smooth rider. Fatigue life usually isn't a concern until you approach millions of cycles.
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With respect, you need to pay better attention in school.
Repeated hard hits = short fatigue life. Light duty cycles = long fatigue life. These things didn't break on the first hit, the metal fatigued and eventually failed. Chromo generally bends in one-hit non-fatigue failure. The cracks take time to start and propagate.

My point is he seems to be running light parts, judging by the way he spins. These things have a finite life when being used in that manner. I encourage him to use his skills to get some parts flowing his way and replace the vital stuff on a regular basis. A snapped fork is wheelchair bait.
 
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jimmydean

jimmydean

The Official Meat of Ridemonkey
Sep 10, 2001
41,136
13,306
Portland, OR
w00dy said:
A snapped fork is wheelchair bait.
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I'm a big dude and roll buff parts to avoid failure. While I still ride like a pussy, the thought of bike and/or part failure is far removed. Run the beefiest crap you can and check your gear often.
 
Chumble spuzz

Chumble spuzz

Chimp
Apr 22, 2003
60
0
Lower VT
w00dy said:
With respect, you need to pay better attention in school.
Repeated hard hits = short fatigue life. Light duty cycles = long fatigue life. These things didn't break on the first hit, the metal fatigued and eventually failed. Chromo generally bends in one-hit non-fatigue failure. The cracks take time to start and propagate.
Click to expand...
Well, that's just like, your opinion man. I guess we can agree to disagree, as without holding the failed parts in hand we can't examine the fractures. If said failed parts have fractures that are characterized by smooth edges, shiny (as opposed to cloudy) gray metal and possibly some minor corrosion then I'm inclined to agree with your failure assessment. Otherwise I'm going to go with mine. Describing a fork as having "snapped" certainly suggests fatigue failure, however, I'm betting that the "snap" was preceeded by a bend. As you pointed out steel does typically exhibit ductile failure when overloaded. Having seen the failures in the videos (broken pedal axle, handlebar weld failure, frame weld failure) I'm going to stick with my guns for the moment.

You certainly make good points about duty cycles and the overall strength of components. As for paying better attention in school, that ship, as they say, has left. :thumb:
 
Chumble spuzz

Chumble spuzz

Chimp
Apr 22, 2003
60
0
Lower VT
Ok Woody,
I took a look at the first video again. What I thought was a pedal axle failure actually looks like it was a crank failure. In fact it does appear likely that it was a fatigue failure, as the crank appears to have failed on the shear plane. Nice work my friend - I'd hire you to perform failure analysis - are you in this line of work?
 
4130biker

4130biker

PM me about Tantrum Cycles!
May 24, 2007
3,884
449
The OP's riding is freakin' awesome!

I remember Mike Tag, I wonder if he still rides? I always liked how he rode- that guy did some crazy stuff.
 
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