Boner

Ahh that explains it, I thought the grubbiness looked familiar

Do you use brushless stuff to power the drum?

Yep, the last picture shows an outrunner mated to a timing belt wheel.

It's a scorpion 4035 series motor that I use. More than enough power from it although I'm not using it to it's limits hence I want to up the lipo cell count

Is there enough space to go to 8S or 10S to really get the drum going? But at that speed you would probably loose engagement; you know it better than I.
We did the same trick for Binky with the Banebots hubs and the GR02's. Its nice to know we are thinking along the lines of an Ex champ

I've not found that boner has an issue with being too slow as it is. It's done severe damage to a number of machines over the years so I don't see much point in increasing the speed. I like that it flips other machines on a regular basis.

I could go to 8s or 10s but the problem is that I don't want to drop below the 3Ah mark which makes the packs a bit on the large side.

I did a bit of testing yesterday with the wheels/hubs on whilst running in the motors and whilst there was a slight wobble it was nothing to get worried about so I think I'll just keep with it.

Down the line I could look at boring out a custom hub to 12mm when I get access to my lathe again.

8-10s seems a bit overkill anyway. There are plenty of effective spinners, brushed and brushless that run on 4-6s. The only 10S I know of it LS4 and they run a huge reduction and rarely go above half throttle, the power is mostly there to get their 6.5kg spinning element moving!

We are using 10S on Binky... its really quite scary.

What are the side walls made of,. they look like 20mm Nylon, with your Ti baseplates and motor mounts

Ah, a reminder to get the hubs finished...

It's meant to be 20mm however when I bought it it was 22mm thick nylon. 4mm hardox bum and 2mm titanium top and bottom