Bomber Sidewinder E-pads?

[David Kirk]

I've just recently picked up some Bomber Sidewinders and I got them with both the firm and soft E-pads. I sent them up the firm blue pads in the warmth of my house and they seemed so stiff even at room temperature as to be be effectively solid. I put on the boot and clipped in and tested the amount of movement of the pivoting plates and they really didn't move. So I swapped the firm blue pads out for the soft yellow and they allow actual movement.

I've only ridden with the soft yellow pads and haven't tired the hard blue ones.....am I missing something? It would seem that once they are cold that it would act as a traditional rigid binding.

What have other done and how did it work for you?

dave

[barryj]

Hey David

Your weight and some momentum will have a lot more applied force than just carpet surfing.

I'm 225lbs. and can tell ya the blue pads do compress when riding.

Unless your around 100lbs. Id say the yellow will allow too much movement on the hill if your getting movement in your living room.

[David Kirk]

Interesting....I'm 6'4" and 190ish and I levered the crap sideways out of the system and my hard red Deeluze sole pads were deflecting but the blue E-pads...they moved little to none.

I'll have to try it with the firm pads and see how it goes. It would be fun to put a travel indicator on each and see what you get with each pad.

 

dave

Edited December 30, 2018 by David Kirk

[barryj]

Just don't think you can get enough leverage/g-force  carpet surfing.

Try it out on the hill first..... 

[digger jr]

I’m 210 lbs and am running the yellows in step ins.( I also have standard SW which I run with blue e pads) I seem to be gravitating to more flexible bindings,maybe because I’m 65 years young/ old now? Using Suzukas with yellow BTS. Also like the F2 Carve RS binding. Carving angles 60-65* front 57-53* rear.There seems to be some riders who like the stiffer  binders and some who like more flexible. That said I’m not done experimenting either. Seems if you run higher angles or Skwal lateral movement would not be good.

The yellows in cold weather also shrink and get a little free play in them which is kind of freaky, but has been no problem for me. Are you using stepin or standard?The flexibility seems to give a smoother ride in bumpier conditions. I also used to think that a stiff binding was needed to get the board high on the edge, but I don’t have a problem with getting the board to hook up. I’ve ridden with very good riders who run stiffer and softer bindings, so might be a personal preference thing.I also think canting is less critical when you have lateral play in your binding.

You could also shim the yellows to “ preload” them a bit.

[David Kirk]

1 minute ago, barryj said:

Just don't think you can get enough leverage/g-force  carpet surfing.

Try it out on the hill first..... 

I hear you....that said I had just my front foot clipped in and I stepped my free foot far to the side then levered the boot very hard to the side....so hard it was very uncomfortable on my calf and the board was being flexed a lot. It was a very large amount of force.

I'll try both pads out and if the blue feels too stiff they can always be softened some.

dave

[David Kirk]

1 minute ago, digger jr said:

I’m 210 lbs and am running the yellows in step ins.( I also have standard SW which I run with blue e pads) I seem to be gravitating to more flexible bindings,maybe because I’m 65 years young/ old now? Using Suzukas with yellow BTS. Also like the F2 Carve RS binding. Carving angles 60-65* front 57-53* rear.There seems to be some riders who like the stiffer  binders and some who like more flexible. That said I’m not done experimenting either. Seems if you run higher angles or Skwal lateral movement would not be good.

The yellows in cold weather also shrink and get a little free play in them which is kind of freaky, but has been no problem for me. Are you using stepin or standard?The flexibility seems to give a smoother ride in bumpier conditions. I also used to think that a stiff binding was needed to get the board high on the edge, but I don’t have a problem with getting the board to hook up. I’ve ridden with very good riders who run stiffer and softer bindings, so might be a personal preference thing.I also think canting is less critical when you have lateral play in your binding.

You could also shim the yellows to “ preload” them a bit.

I hear you.

I borrowed a set from a friend and rode them on a cold day and they developed some freeplay so I made some .010" shims and this stiffened things up just a bit and got rid of the play even in the cold.

I'm not using step ins.....just the simple toe levers.

I'm picturing stiffening the yellows with some shims and/or softening the blues by drilling some very fine (.020" or so) to soften them if need be.

 

dave

[daveo]

This is a thread @forrest might be interested in. 

[David Kirk]

So  bit of a follow up....

I'm in the bicycle business and have been building and documenting the behavior of bikes on the road and in the lab for 30 years and I put a bit of that otherwise useless skill to work in seeing how the blue and yellow pads differ.

I set up a load/deflection test to see how much movement the two pads have relative to one another. The main binding plate was bolted to a rigid table right at the edge. The toe plate was bolted the the main base plate and the bail and pin was removed. In its place was a steel rod that was cantilevered out off the table and a heavy weight was hung from the rod (wish I'd thought to take a photo). So the weight was hung off the lever rod and the toe plate would twist. I then documented how much the plate deflected. Simple and repeatable stuff.

I first tested the soft yellow pads and got a toe plate deflection/pivot of .021". I then swapped in the hard blue pads and repeated the process and got a deflection/twist of just .008". So what I was feeling on the carpet and the snow was borne out....the blue pads were a full 62% stiffer.

I then put the yellow pads back in but this time I put a .010" shim under the pads effectively preloading the pad. I got a deflection/pivot of .016". The shim and preload set up resulted in a increase of stiffness of 24% over the stock yellow set up.

I have tested the yellow pad shim combo on the snow and found it rode very well and it did not develop any freeplay or slop on a cold day like the yellow pads without the shim had.

So the takeaway is that the blue pads a much stiffer and that if one wants to find a stiffness somewhere between the blue and yellow that a shim can be an effective way to get that done.

Fun stuff to play with.

dave

[Corey]

That's awesome, Dave!  Thank you very much for the research.  Now I need to get some 0.010" shim stock.  I like the yellow pads under my SI Sidewinder heels while riding, but noticeable slop is a little freaky in the lift line.  I've been running blue heel pads and yellow toe pads per Fin's recommendation.  

The deflection curve should be highly non-linear given the properties of elastomers, so it would be interesting to try with varying weights or lengths of rods.  This is highly academic though as the numbers wouldn't change what I do/feel.  

To go full science geek, then do the same with F2 bindings to compare.  I wouldn't be surprised if Fin did exactly this during SideWinder development.  

[David Kirk]

3 hours ago, Corey said:

That's awesome, Dave!  Thank you very much for the research.  Now I need to get some 0.010" shim stock.  I like the yellow pads under my SI Sidewinder heels while riding, but noticeable slop is a little freaky in the lift line.  I've been running blue heel pads and yellow toe pads per Fin's recommendation.  

The deflection curve should be highly non-linear given the properties of elastomers, so it would be interesting to try with varying weights or lengths of rods.  This is highly academic though as the numbers wouldn't change what I do/feel.  

To go full science geek, then do the same with F2 bindings to compare.  I wouldn't be surprised if Fin did exactly this during SideWinder development.  

Cool - let us know how things feel to you.

 

dave