What ever happened to 6 day trials bars (skidplates, mud packing) ?

I dropped the skid plate on my WR450 to find it packed with 5 pounds of mud.   I weighed it.


I'd like some engine protection that isn't as prone to packing up with mud.  Back in the 80s bikes used to have bars protecting the crankcase.    What became of that and why isn't it used anymore, at least for the bottom portion of a skid plate ?

Bars don't slide over logs well and do not protect against punctures.  The trick is to put a piece of low density foam between the skid plate and the engine.  That keeps the mud out.

I don't understand how it gets in there in the first place.   Its not like I had the bike in deep mud.


The mud was packed in solid.   It was heavy clay.    Does it collect the mud that gets thrown off the front tire ?

Just keep that front wheel off the ground and the mud problem will disappear.


But really the foam is the trick.  It is cheap and as a side benefit it will reduce the amount of engine noise that gets bounced back towards you.

Thanks for the suggestion.   I'll give it a try.

Good topic, just last night I changed my oil and had the brownie block in the skid plate and yes it was about five pounds. I'm kinda of getting tired of it too, as I don't understand how so much gets packed in there. Had a friend tell me about the foam once and I tried it on my YZ but after a short while it just gets compressed and I worried about it causing the motor to get hotter than it should. Do you think it could cause the motor to get hotter? or am I worried about nothing? Because I'm ready to try some foam again.

The bike is water cooled.


It takes 30 seconds to wash the mud out with a hose.

Yeah, I realize that, but the motor is pretty crammed in there. And there is no washing the skid plate out with a hose or I would not have the problem. 

Yeah, I realize that, but the motor is pretty crammed in there. And there is no washing the skid plate out with a hose or I would not have the problem.

Ditto. My mud would not budge, even with a 1600 PSI pressure washer.


The mud is entering from the gap at the front of the skid plate...foam will help but the best solution is a different skid plate, one that closes off that section....and foam.


I've installed the Acerbis plastic skid plate as it blocks the opening in the frame quite nicely. A pad of open cell foam trimmed to fit completely prevents any mud from collecting between the frame, engine and skid plate.

FYI, I thought that I was going to solve this problem by lining the underside of the engine with plastic vapor barrier as well as the top side of the skid plate and injecting Great Stuff foam into the space between. It turns out that Great Stuff starts to burn at 240F ! Lucky I checked !

I think Mr Lowrance is right,  it does look like it goes down the top of the skid plate on this 12WR, and looks pretty simple to block that opening. I'm going try blocking that first before I line the skid plate with foam.

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