What is the difference in flex characteristics and handling between the extra tough and regular arms? I ordered xtra tough instead of regular by mistake.

The NB comes with the XT arms. I don't think it has flex built into it, but it does have a different outer shock mounting location, and a stronger blend of plastic.

thanks

Here they are:
https://dl.dropboxusercontent.com/u/...G_8723-001.JPG
https://dl.dropboxusercontent.com/u/...G_8725-001.JPG
https://dl.dropboxusercontent.com/u/...G_8726-001.JPG

In the photos it looks like the the clutch springs run green.green.red.red instead of green.red.green.red. Can't tell for sure, but if it is, there may be too much slip because the shoes are trying to clamp down only one side of the clutch bell at a time.

Also, you probably do, but check for drag on buggy (brakes etc)

1. As mentioned it looks like you have the springs in wrong.
2. You need to put a 45deg bevel into the bottom edge of the shoe where it's coming out from under the bell otherwise the shoes will hang up on the bell and not return properly.

1. Springs are stock for NB48 - 2x green plus 2x gold
2. I'll try to do this on my new shoe set grinding some edge with sandpaper or dremel, wonder why this isn't mentioned anywhere.

Like it was said. Your springs are on the clutch wrong. They should stagger. Green gold green gold. That will help with wear. This clutch has good wear characteristics.

We are not trying to say you have the wrong springs but that they are in the wrong order. Unless its camera shadows playing tricks it looks like you have


GREEN-GREEN-GOLD-GOLD

It should be

GREEN-GOLD-GREEN-GOLD

Two springs of the same color should NOT be next to each other but 180 apart

1/ Yeah I couldn't tell the colours properly but they should be installed greens opposite to each other, golds opposite each other.

2/ Your shoes are getting a shoulder on them because the clutch bell is shimmed out past the edges of the shoes. You can bevel the shoes as mentioned or you may be able to shim the clutch shoes

I am NOT a big fan of running the bell that close to the flywheel. There is enough
radial play in the bearings to let it hit the flywheel when things flex.
The shoes are simply to close to the flywheel to use the entire surface without
the bell riding close enough to cause mystery flames. Best to bevel off the
bottom millimeter or so and keep the shoulder that develops there from hanging the
shoes up.

I am curious how having the spring on wrong effects bearing life.

Also those pads have a heap of life in them left

The key measurement is 23.4mm taken on the outside with callipers

There is a great video with Adam drake showing how to measure it correctly and when to change the shoes

Are there any clutch bells out there that will fit the car but are taller(or longer) then stock bells?

I dropped in a new motor and I find that the clutch bell is about 1mm short from being even with the spur gear. As if the motor was moved back just a hair to far. I cant shim anything enough to bring the bell forward or else the screw binds on the front bearing not allowing the bell to spin freely.

So it would seem that my options are finding a clutch bell that is longer or taller then stock,run with it as is(it's only 1mm at best..more like .5mm). Or return the motor for something else.

Hmm, i'll doublecheck my spring order (right now i'm pretty sure its fine), but i haven't modified my shoes system since first build. Looks like lower spring on the first pic is green due to green fuel line reflection, which i use to protect fuel intake and pressure tip.
I have something about 0.5 or 0.6mm shimming from the clutch nut, a tick smaller amount leads to touching something inside bell during rotation, but i'll try to shim a bit closer again.