Crash bars - to be or not to be that is the question

[mercator1]

Unless someone has done some type of stress analysis on bikes with/without bars, conjecture about whether any damage to the frame that may or may with them is worse than any damage that might be caused by the torquing effect of hitting and dragging a cylinder head, is just that.  If someone has such study results available, please post them.

[guest2360]

That question should be put to the manufacturers of aftermarket bars before you buy. 

[mercator1]

That question should be put to the manufacturers of aftermarket bars before you buy.

Or of cylinder guards before you buy.

[guest2360]

Or of cylinder guards before you buy.
Quite.  I have no details but was recently told about someone who had experienced a cracked engine casing where a set of Wunderlich bars were attached.

[mercator1]

Or of cylinder guards before you buy.
Quite.  I have no details but was recently told about someone who had experienced a cracked engine casing where a set of Wunderlich bars were attached.

How is that since they don't attach to the engine casing?

[Tango]

I have no details but was recently told about someone who had experienced a cracked engine casing where a set of Wunderlich bars were attached.

Was a top box fitted maybe the blame could be placed there as well !!


or maybe it was because it was involved in an incident


or maybe ..........................................................................................

[guest2360]

Don't know any details.  Probably bent in somewhere onto one point. 

[mercator1]

Don't know any details.  Probably bent in somewhere onto one point.

In that case, the head itself would have taken all the brunt of the force without them.  Some part of the energy of the crash was absorbed by the bar, and some transferred to the frame.  If there was still enough energy to damage the head, then the head itself would have otherwise taken all of that energy and been damaged further.

[richardbd]

That question should be put to the manufacturers of aftermarket bars before you buy.

and your insurance company.


I bet they'd have something to say if non-declared bars caused additional damage in any accident...

[mercator1]

and your insurance company.
I bet they'd have something to say if non-declared bars caused additional damage in any accident...

I've never heard of an insurance claim being denied because the bike had engine bars in the history of motorcycling.

[richardbd]

I've never heard of an insurance claim being denied because the bike had engine bars in the history of motorcycling.

Maybe your insurers aren't as keen as ours to avoid paying out.  Over here we have to declare any modifications to the bike and many are likely to affect the premium.  Non-declaration of any modification can definitely give an insurance company a reason to decline or modify a claim - that's why they ask in the first place...

[fatnfast]

The Wunderlich bars for the oilhead 1200rt's claim to distribute the load in the event of them being used in anger. Hopefully I will not have to test them anytime soon. And yes, you should declare them.
I have engine bars on my 1150. They earnt their keep a few years back when an old dear hit the accelerator instead of the brake (her admission to plod) emerging from a side road. The bike was still rideable :-)

Not only did they protect the cylinder head, they also did a stout job on her car......

[guest2360]

Which prove you should stick with OEM kit.

[fatnfast]

Indeed, the GS bars are original BMW bars.
However, if they were not fitted the damage to the head could have been a show stopper. The plastic guard broke in two. I think as long as you recognize that bars are aimed at low speed or stationary offs, then go ahead and fit them. If your expecting anything more, you may disappointed.
For the TC there are no genuine bars available, only head guards, so the option is aftermarket ones.
I thought the Police spec bikes have engine bars made by BMW fitted though?

[guest2360]

Yes they do for Authorities bikes and are not available for general sale.  Their design seems to be married to the rear safety bars which are an integral part of the special pannier frames. None you would want on your pride and joy.