K75S Drop protection bars

[Martin]

After the last drop and $400.00 Au out of pocket I finally decided to do something. I have decided to make my own bars. I have looked at various mods to the belly pan and have decided not to go that way for a couple of reasons. One I don't want to cut into it and oil changes would require the removal of the bars. I have come up with a couple of designs I prefer the one with the springs but sourcing the springs that are small enough and strong enough might be a problem. I have also thought about substituting the spring for silicone.. I have worked out a clamp that I can clamp around the frame. The left and right bars will have to be different lengths and the right side diagonal brace has to clear the coolant hose. I went into Brisbane on Friday to BMW to pickup the special mounting bolt that I had ordered, only to find that had been substituted by longer allen bolts doing away with the rubber shock absorber. The drawings are not to scale and are preliminary they are just to give you an idea of what I am trying to achieve. At this stage I am looking for feedback negative or positive, it might not be practical.
Regards Martin.

[The Dude]

 At this stage I am looking for feedback negative or positive, it might not be practical.
Regards Martin.

[/quote]k
Great concept!
The shock absorber potential of the springs is nice but hopeful(No energy absorption and significant loads).
My concern would be about unintended consequences.The possibility of damaging the frame through the brace with a "higher speed"off.The system should be "sacrificial"in that case.SS is tough stuff.Mild steel is more ductile.
Would the bars be usefull as an alternate foot rest,for those long distance stretching moments?

I don't have crash bars..yet and have had one (big) slide on the RHS needing to replace the casing.Old one on my "wall of shame"which I see,as a reminder,every time I go out....
All the best with it.

[Martin]

Thanks for the feedback, I did think about doing away with the brace but was worried the bar might bend up into the fairing. I would really like to put springs in it to absorb some of the shock, but have been unable to find anything. I  hear what you are saying about stainless steel and will probably go with mild. It's hard trying to make something to prevent drop damage without doing more damage. I have never had a high speed get off but have had a few virtually stationary drops. At the moment I am chasing the engine mounting bolts that have the threaded heads to take OEM crash bars. Local BMW wrecker wants $10.00ea Au  :yow
Regards Martin.

[The Dude]

Yeh,"they're" somewhat top heavy and inclined to want to roll over whilst being pushed around 'bit like my current avatar! (Time for that to be changed...)
     :falldown:
'Just been pea gravel at junction turn offs,dogs and oily decks on car ferries,for me so far.Pride of ownership is more about "street cred",now....and that odo number.Takes one to know one,tho.
Good luck!

[Martin]

Since 1969 2 kitty litter, 1 little old lady threw open the door of her bug, one guy pulled out from kerb, one red light runner, one truck tyre retread took out fairing and scarred helmet, one car park accident. My fault, one rubber handle came off drop, one hit the wheel clamp on my lift and bounced and drop. I think I am surviving well. :clap:
Regards Martin.

[The Dude]

Interesting!
Desrves a new thread....I too have a list of experiences,some of which I try to forget but must remember at all costs.Continual vigilance.So very hard.Truck driver mileage inevitably results in a long list.
Many similar ones to wot you've been through.They become indelibly imprinted and continue to be top of mind when running through the loop of "what could possibly go wrong,now"?"what could possibly go wrong,now"?"what could possibly go wrong,now"?
 The high speed truck tyre retread random bounceing is quite common,I suspect.The handlebar grip slide off,oh yeh!just when you thought you'd caught it from going over ,the wrong side.

Most sobering and least wanted to see have been three motorcycle deaths right in front of me from unknown bikers who had just overtaken me seconds previous.Showing off with pillion,being stupidly fast with pillion,rear ending and crushed in bad conditions, commuting...sickening and indelibly imprinted having to stay for the aftermath and be a court witness.Appologies for the extreme bummer accounts.I don't mention them,much....
Sometimes, I don't go 'cause I loose my bottle,predicting.

Remember how you think things like:
If only I didn't .....in a another loop,when you're picking yourself up.

Also, I gave up riding for six years,just before my self predicted fatal accident!Just got too cocky.Kept the bikes though and much more sober now but ya never know WTF.
Best crash bars are the ones you never need.

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there."
All the best.

[Photog]

Sounds like an interesting project.
For springs, how about valve springs from one engine or another? Maybe from something like a sub 10 HP lawn mower engine?

[Martin]

Thanks Photog I am still chasing, I will look at mower engine and 4 stroke whipper snippers. Still pondering whether to pay $20.00 AU for the two mounting bolts to local BMW wrecker. And Dude it was the lift handle rubber, I ended up with the grip in my hand no bike.  :hehehe
C.heers Martin.

[Brad-Man]

Thinking a bit ouside the box...

What about using some open cell foam instead of a spring in the top example/diagram.

You could play with the length of the tube and foam and possibly have a viable solution to the spring issue.

Would be fairly easy to remake/refill...

[Martin]

Brad I have thought about using silicone but never thought about foam, a good thing about this forum is you get plenty of ideas.
Thanks Martin.

[The Dude]

 :oldguy:  :riding:  :falldown:  :deal:  :musicboohoo:

[Brad-Man]

If the thought of a beer getting warm doesn''t bother you, you could cut up one of those foam coozies and stick as much as you need in there...

[Martin]

I have a couple of sheets of open cell foam. I've decided to bite the bullet and get the gold plated engine bolts from the local wrecker at a cost of $10.00 ea. Once I have the bolts I'll know what size tube to buy and I can go from there, probably try and do a couple of experiments with the suggested materials.
C.heers Martin.

[Laitch]

I have one more shock absorbing material for you, Martin. I didn't notice the extension length of your tube. These bumpers are used to increase support on snowplow front suspensions. The are tough. They have countersunk holes for attaching to the steering assembly. They could be attached with shear pin style bolts.

[Brad-Man]

Just a thought on the clamp tube...

The further away from any frame junction the longer to disribute stress...

Just thinkin'...

[Martin]

Thanks Laitch and Brad I will look at bump stops although not for snow plows, we do have a slight shortage of snow plows. We are in winter at the moment and the temperature has dropped to 23o C, but still no snow.
C.heers Martin.

[The Dude]

Shock absorbsion is not needed.Keeping the precious bits away from the hard stuff is.
These are popular:Can't use them as highwayegs though.

[Martin]

There's no practical way to mount Oggy Knobs on a K75s. Unless you mounted them on the end of the drop bars. I still haven't decided whether to put rubber stops on the end of the bars or nylon.
C.heers Martin.

[The Dude]

There's no practical way to mount Oggy Knobs on a K75s. Unless you mounted them on the end of the drop bars. I still haven't decided whether to put rubber stops on the end of the bars or nylon.
C.heers Martin.

True,Just an example of a simple and effective design....great solutions involve rendering down to the essence of what is needed.Complexity satisfies something altogether different...'just a lifetime of observation working as a design engineer. :oldguy:  :dunno