Crash bungs/protectors ?

[LotusMartin]

What can I add to my bike to offer some protection should the worst happen and I drop it? I've seen handlebar sliders and front axial bungs but does anyone bother? I'm not talking about lowsiding it down the road, more protection from a dead fall.

The bikes a 2013 1200GS Adventure which at the moment is mint - I'm hoping to keep it that way - Hope for the Best, Plan for the worst

 

[Deleted account 211025001]

From a dead fall engine bars will do the job.

Andres

 

[Deleted account 190920001]

Yep I agree with the engine bars.

 

[Pablo1]

From a dead fall engine bars will do the job.

Andres

i can vouch for that

 

[Ted]

If you are unlucky enough to be moving as it falls, or no panniers fitted. Rear drive bung will stop it getting any damage.

 

[(RIP) Miff]

Fit some sacrificial panniers.

 

[SteveM]

If you are unlucky enough to be moving as it falls, or no panniers fitted. Rear drive bung will stop it getting any damage.

Where did you get that Ted?

 

[Paul C]

I fitted a 2nd hand set of these...

Made by Wunderlich. However, I used a better quality clamp from a marine suppliers rather than the P-clamp shown. Dropped it once in a ford and it got marked so I guess it did its job. However, when pushing things on a bit the RH one will touch down.

 

[TLSgazza]

If you are unlucky enough to be moving as it falls, or no panniers fitted. Rear drive bung will stop it getting any damage.

Wassat in your rear spindle hole, looks bling.

 

[ricalnic]

If you are unlucky enough to be moving as it falls, or no panniers fitted. Rear drive bung will stop it getting any damage.

http://www.motorcycleparts-hornig.c...P2/Alu-High-grade-Steel/Cardan-Crash-Pad.html

 

[Bendy toy]

I have a bung on the rear trunnion spindle. Its common sense as a low speed drop can scrap the final drive casing.

However, I'm not impressed with crash bars. I dropped my Adventure last spring at about 15mph. The RHS crash bar was bashed backwards enough to bend the rocker cover protector. Any further and I'd have been looking at rocker cover damage and potentially cylinder head damage where the cover bolts thread in. Had I gone down on the left, I'd expect the rocker cover to be damaged (crash bars much closer to rocker cover) and that can lead to cylinder head damage if the rocker cover bolt hole lugs get cracked.

The GSA engine bars are integral with the tank protectors so its not a simple task to just chop them off. However, if I was wanting to protect a GS, I'd go for the Wunderlich head protectors that have sacrificial sliding pads built wunderlich.sportouring.net/cylinder-head-protector-1556 There are also carbon fiber head covers that do the same job. There are a few on eBay, some also have sacrificial sliding pads.

We need to think about where the crash forces go. The Wunderlich bars shown above will for sure be stronger than floating crash bars (like the GSA) but where will the crash forces go and can the engine case take that force. If the bike goes down hard enough to rip away a rocker cover complete with its slider then that's the least of anyone's worries. But a simple bump could become a nasty surprise if the crash bar causes magnified forces on parts not designed to take those loads.

Not only that, servicing becomes a chore if the crash bars have to come off the bike.

The Off Road rider training bikes dont have crash bars. They dont fuss about cosmetic damage and just replace the rocker covers as needed. For the rest of us, add-on covers that take the scrape, ideally with replaceable crash pads certainly make sense.

 

[Deleted account 190920001]

I have a bung on the rear trunnion spindle. Its common sense as a low speed drop can scrap the final drive casing.

However, I'm not impressed with crash bars. I dropped my Adventure last spring at about 15mph. The RHS crash bar was bashed backwards enough to bend the rocker cover protector. Any further and I'd have been looking at rocker cover damage and potentially cylinder head damage where the cover bolts thread in. Had I gone down on the left, I'd expect the rocker cover to be damaged (crash bars much closer to rocker cover) and that can lead to cylinder head damage if the rocker cover bolt hole lugs get cracked.

The GSA engine bars are integral with the tank protectors so its not a simple task to just chop them off. However, if I was wanting to protect a GS, I'd go for the Wunderlich head protectors that have sacrificial sliding pads built wunderlich.sportouring.net/cylinder-head-protector-1556 There are also carbon fiber head covers that do the same job. There are a few on eBay, some also have sacrificial sliding pads.

We need to think about where the crash forces go. The Wunderlich bars shown above will for sure be stronger than floating crash bars (like the GSA) but where will the crash forces go and can the engine case take that force. If the bike goes down hard enough to rip away a rocker cover complete with its slider then that's the least of anyone's worries. But a simple bump could become a nasty surprise if the crash bar causes magnified forces on parts not designed to take those loads.

Not only that, servicing becomes a chore if the crash bars have to come off the bike.

The Off Road rider training bikes dont have crash bars. They dont fuss about cosmetic damage and just replace the rocker covers as needed. For the rest of us, add-on covers that take the scrape, ideally with replaceable crash pads certainly make sense.

You also need to consider the extra forces cause by crash bungs. Your bung on the the trunnion may stop some scraping but it it also puts a lot of load onto a component that was never meant to take it. I have seen some major chassis damage caused by crash bungs, enough that I wouldn't consider ever using them.

Bending of the crash bars is by design. It absorbs energy in bending the same as crumple zones do in a car. If they were absolutely rigid then chassis and engine casting damage would result possibly creating a financial write off for a relatively minor off.

The off road school don't need crash bars as they don't have to get out of the middle of nowhere. A small drop cracking a valve cover leaving the bike un-drivable doesn't matter where it does if your miles from anywhere. They just come along with a van/pickup and lift the bike. Of course nobody needs them if they only go to either.

I have been glad on a few occasions that I had the adventure crash bars but you pays your money and make your choice. It's the nature of motorcycles that even a relatively minor drop off the stand can cause a lot of damage, just ask any sport bike owner.

 

[Bendy toy]

My issue is not that the standard crash bars bend, but just how easily they bend. Also the LHS has almost nowhere to move before it's become a huge stress raiser onto the rocker cover. They also fail to protect the rocker cover sides so additional crash covers are needed.

The Wunderlich style braced bars look like they'll give better coverage but they won't bend at all risking heavy stress on the main frame mounts just below and behind the cylinders.

The final drive bung I use is almost entirely polypropylene plastic. It's retained by just one M6 nut that expands it into place. It's crash load is taken by the trunnion outer face. The metal frame affairs some people use are IMO risky to say the least for cracking the mounting lugs.

 

[Bendy toy]

I welded additional mounts to my Yam Diversion 900 frame specifically to carry crash mushrooms.
They were as close as possible to a cross brace tube otherwise I'd be simply giving a bending point for the frame.
There were no upper engine mounts so the bike had effectively nothing else solid enough to protect the fully exposed upper frame.
Thankfully they were never tested in a crash but they fared very well when 250kg of bike plus luggage rolled off the side stand.