Bruiser / RN36 transmission

[Raman36]

I have 2 3 speed transmissions. One that came with my kit and one that I picked up from a seller.

The one from my kit works flawlessly. The one I picked up, not so much.  
 

I’ve opened both up, compared them side by side for shimming, spacing. Identical in build.

I reassembled both and nope, 2nd unit will not shift into top gear or low / 4WD gear. Stays in centre. 
 

The 2 shift rings, shift hubs and dog legs all look good, no damage. So I’m just scratching my head here. 

[Theibault]

That's tough one. I'm not sure I have a solution other than putting the gears from the one that works into the case of the one that doesn't and seeing if it still works. Then go from there I guess. That's what I'd do in this situation. Just be careful to keep track of what parts are from which transmission.

[Raman36]

22 hours ago, Theibault said:

That's tough one. I'm not sure I have a solution other than putting the gears from the one that works into the case of the one that doesn't and seeing if it still works. Then go from there I guess. That's what I'd do in this situation. Just be careful to keep track of what parts are from which transmission.

The actual gears are fine. It’s something to do with the shift rings sliding onto the hubs. The rings need to slide over the hubs for gear change and it’s not happening.

The ones in the gear box that’s not behaving are newer which makes me think the gear box needs break in 🤔 

I’ll keep tinkering as I’m quite persistent lol.

On a side note, the black plastic gears are really brittle. I have damaged the low gear 2 times now when climbing something challenging. So I now have the slipper clutch installed.

There was a guy on eBay that sold these in brass.. but he’s long gone.. those would make the gear box bullet proof 

[RichieRich]

Are you sure the seller sold you an authentic Tamiya transmission? There is a clone version and the internal parts are not as smooth which upsets the shifting mechanism. The clone is a copy of the current Bruiser 3-speed. If you have an older original 3-speed, then there might be a different issue.

[Raman36]

I had them side by side and all the internals are identical in finish. same quality anodising on the shift rings. So if it’s a clone, it’s a darn good quality copy 😂

[76jimmy]

Hey guys first post. I'm new here. I just got a vintage bruiser myself in a trade. I came here to share my experience with the model. All the original rubber parts were pretty badly worn and cracked. The transmission wouldn't shift properly. After disassembly and inspection I found the rubber plugs were dragging on the synchronizing gears making shifting from the gears "sticky". I was able to replace the stock plugs with some 8mm rubber plugs cut down so they didn't contact the gears. Reassembled and lubed with lock-ease graphite lubricant. I figured it it works on brass lock components why not brass transmission components. Works like a charm. No more missed gears or funny noises when shifting.