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Old 03-30-2009, 03:49 PM   #70
glitch_oz
Beastly Adventurer
 
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Joined: Apr 2006
Location: AUS
Oddometer: 1,668
Quote:
Originally Posted by The Griz
Your profile doesn't say you even own an F800GS, so I'm going to roll with that assumption. Are you qualified to make these statements?
Doesn't make a diff, does it?
Physics are physics, impact forces are impact forces...regardless of brand/ model.
Qualified?
If common sense and 35 years of wrenching and riding (incl. building a few bikes over the last few years) counts....



Quote:
Originally Posted by The Griz
When speaking of the Holan, BMW, Adv Spec, etc.: the brunt of the force from a hit would direct most of the force to the frame. The main connection point for these crash bars is on the sides of the bike, by the top of the engine. This connection is directly to frame, and designed by BMW and other to take the brunt of the impact. Not much would happen to the small connecting point at the bottom of the engine. And actually, the Holans are designed to relieve stress at these connection points as well.
??
If a hit is directed upwards and looking at the twin-brace of the bars running vertically up the side, those 2 little 5mm Allen bolts at the bottom will either rip out of their their threads or just snap, the curved mounting plate hitting the engine cover (which is usually very thin cast).

The more likely scenario is a drop while riding... directing impact forces upwards/ rearwards....and as the upper mounting location is more solid than the bottom, that upper bolt will act as a pivot... again tearing the bottom plate off the casings (as the down-leg is nicely braced and therefore fairly solid = transmit forces).
God forbid if those down-struts get snagged on a solid branch or the edge of a rock (creating rotational forced on the bottom bracket).

It's the same problem as on the DL650, which just hasn't got any decent mounting points to mount a bash plate...some aftermarket supplier decided to make a "super-tough" bashplate from 5mm alloy, all braced up and beautifully finished....with a top-mount on the front cyl head.

Great piece of work that thing .....for an ashtray.
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pete

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