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Old 08-10-2010, 04:17 AM
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scotto- scotto- is offline
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Join Date: Jun 2010
Location: Ridin' inSane Diego, CA.
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Wink Re: 2nd broken frame

Originally Posted by BarelyAWake
scotto-...right, it's true stuff breaks - but I think this may be about whether or not the engine itself is primarily responsible, if the lower end bikes are truly suitable, and if there's any frames in particular that should be avoided because of that.

lol - ya go jumpin' everything in sight and ofc yer gonna break stuff engine or not, I too "fondly" remember breaking the Dtube/head weld on various bikes jumping stuff, mostly unsuspended bikes not made for that sorta shenanigans - and not motorized.

If you track down the source of that "stress", practice a lil postmortem forensics - there's much to be learned. For instance - cracked/broken welds on the Dtube (unmotorized) are usually a sign of landing front wheel first, but may be just poor welding skills, undercut in particular. A jumping bike should have additional gussets in that location, as you've noticed. Bottom bracket breakage is primarily the fault of insufficient quality components - it is after all where ALL your weight is when you land... if yer still on the bike heh, handle bar breakage is usually a sign of bars that are too long (excessive leverage) and/or don't have the crossbrace - all of this is obvious after the fact, but would still be a problem if people didn't think about the cause and take steps to prevent it.
Just want too say that the same spot I was referring too isn't prone to breaking just because of jumping.......I've also snapped an aluminum frame on a $2000 Mtn. bike in 1990 by stuffing my front wheel in a rut of the same size at the bottom of a gulley on a downhill decent. This is opposite force that resulted in a fractured frame in the same sweet spot. No motor involved, same result shall I say......over-stressed. As in stress and fatigue....and I'm not neccesarily talking about weld failure, but the double-butted tubing itself. Thank you for fixing the quote and we all know suspension rules and hard tails drool.....don't we?
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Last edited by scotto-; 08-10-2010 at 04:33 AM. Reason: fixed quote
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