Bash plate design thoughts

[Mouse]

I'm in the process of making a new bash plate for my 1200, and have been wondering about the way it's mounted. Normally the plate is attached to the sump by four rubber buffers, which are quite easy to break. Also this means any impact to the plate is transmitted to the engine through four distinct points, although presumably the engine case is designed with this in mind.

I was thinking of adding some more buffers to my new bash plate - possibly one in the centre of the bottom section, and one at the front. The front of the bash plate will be angled up more then the original to protect the exhaust pipe. The buffer at the front could probably rest against the angled front of the engine, just below the alternator belt cover.

The idea is that any impact to the plate will be transmitted to the engine over a wider area, and so would be less likely to cause damage. The extra font buffer would also protect the plate against being ripped off backwards to some degree. I'm not planning to attach these extra buffers to the engine, just bolt them to the bash plate and let them bump against the engine in the event of an impact.

The possible problem I can see is that, while the force will be lessened due to being spread out more, some of it will be transmitted to parts of the engine case that are not designed with this in mind. I plan on using quite soft rubber for these buffers, to allow the bash plate to deform in the event of a large impact, after all it is in the end a sacrificial device and if the plate is destroyed but the engine survives, it's done its job.

Has anyone got any thoughts on this? Is it a good idea or am I asking for a big hole in my sump?

Thanks for your input!

 

[Vern]

I'd be very careful about bringing the plate up above the exhaust pipe,it's so easy to make the bike run hot by changing what appears to be a little bit of metal!As for spreading the load more,that could be a real can of worms unless you know what the inside of the cases are like,and where the webs of the castings are.We used to use a really trick foam/sponge/rubber stuff for all the sump guards we used to make for rally cars.It's everything proof,oil/petrol/brake fluid/fire/nuclear war,and it only compresses in a linear direction from the impact.It costs a fourtune,but if you measure how big a bit you need,I'll see if I can scrounge a bit for you.All you do is fit it between the sump and the guard so it can't go anywhere.It used to stop 6mm sumpguards hitting the sump after 100+mph belly flops in a 800kg car,so it should be just about alright for a GS

 

[Mouse]

Good point about the heating aspect Vern, I hadn't thought of that!

I'm not going to totally enclose the pipes, and the bike doesn't seem to run hot when the pipes are covered in an inch of mud So hopefully I'll be ok! But if it does run hot I can just trim the plate down a little.

Thanks for the foam offer - when the thing's made I'll measure the gap. Do you rememebr what that stuff's called by any chance?

 

[earthmover]

Don't T**rat**h do a sumpguard that spreads the potential impact over a wider area? Seem to remember seeing one in their catalogue, but don't trust myself to have a look in case I see something that I "need"
Mark

 

[Mouse]

Yes touratech do something like I am describing, they also do a larger bash plate. The whole lot would set you back well over 150 quid though, I'm aiming for under £50

Also the fact that touratech sell it isn't in my mind a guarantee that it's a good idea - hence my fishing for wisdom from the learned minds on ukgser

 

[Vern]

The other thing to do as well,is make one out of cardboard first,to see if you are going to run into any stupid problems that you hadn't thought about.It's loads easier to sit there with a pair of scissors than a pair of snips,and you don't waste any ally in the process.

I can't remember what the foam is called.It used to be delivered in the dead of night by the sump guard pixies. I think it might have been called spongeyformus unobtainium,but I might be wrong

 

[Mouse]

Got the prototype back .... it's looking good (in a functional way )