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I'm attempting to use the RPM 2.65 hydra shaft (#8058) in the RPM trans case to use the B4 slipper. I picked up one of those shafts and the rear slipper plate sits out quite a bit further on the shaft compared to a B4 shaft. Am I looking at something wrong? Basically the flat part of the hydro shaft that the slipper plate rides on, doesn't extend as far back on the shaft as the B4 shaft essentially pushing the whole slipper further out.

Here is a pic with the RPM hydra shaft on top and the B4 shaft on bottom.

A possible solution just dawned on me....... I suppose the pinion could be run the other way around to make up for the spur setting out more?

isn't the b4 slipper spring a problem on that topshaft too?

I think the new spring should be fine, it's a much bigger diameter than the old one. If not, just find the thick plastic Losi slipper spacer and spring and use those, that's what I did

looks easy enough to grind the flats back to match the B4 shaft with a dremel. Use a cutoff wheel as a very narrow grinding wheel, and grind back and forth in the direction of the shaft.

Yep, the B4 spring won't fit either, too small inside diameter. The area on the B4 shaft where the spring fits is turned down for it. I guess the only real solution is to have it machined to work. Adam Lancia, do you have any pics of what you are using?

Here's a pic of what I've done to make it work. IIRC, I used that Losi thrust "cup" thingamajig just to take up space on the top shaft. The thicker Losi slipper spacer has a shoulder that prevents it from sliding all the way down to the slipper hub.... I think... I don't have the transmission in front of me and it's been a few years since I assembled it. I had also roughly machined down the flats to allow the slipper hubs to slide back to the same position on the top shaft as the B4 top shaft. Mine was a bit of a hack job since I think I may have done that when I was a bit younger and didn't have the steady hand I do now. I'm sure you'd be able to make a good job of it with some time and patience.

Hope that helps!

Thanks Adam! I did discover this:
http://www.ebay.com/itm/LOSA3124-Losi-Spring-Cup-Spacer-and-Washer-/320766654354?pt=Radio_Control_Parts_Accessories&hash=item4aaf2eb792


What outer slipper plate is that?

It might be a Losi plate but it could also be an Associated plate, I'm pretty sure they're almost identical except for the shade of anodizing. That link has exactly the parts I used minus an actual thrust bearing (not needed, not even sure why I used it in the first place...). LTO Dave's got that set for sale in the BST too

askbob wrote:Yep, the B4 spring won't fit either, too small inside diameter. The area on the B4 shaft where the spring fits is turned down for it. I guess the only real solution is to have it machined to work. Adam Lancia, do you have any pics of what you are using?

Try the spring from the 4.1 v2 slipper. Much bigger diameter.

likw this, i think the owner is also a member here ( sorry just posted ot just for reference).

slow_jun wrote:likw this, i think the owner is also a member here ( sorry just posted ot just for reference).

THAT'S where that picture is! I couldn't find it on my computer for some reason, thanks slow jun!

THAT'S where that picture is! I couldn't find it on my computer for some reason, thanks slow jun!

ahhaha, i think i saw your post before and wanted to do what Bob is doing now, but eventually the shaft went to him.

Thanks fellas! I ordered the Losi parts to do just that. Think you can get by without extending the flat area on the shaft where the back plate rides?