DazFX,
I do the same as Bren. Even when I built I thought this cannot be correct.
As for your wheel bearings try AVID bearings. The 19mm bearings will be available shortly.
I had the same issue when I ran a Losi. What annoys me about this setup is the different size bearings wear at differing rates. Xray stated the inner bearings take more load from the CVD's, but the outer bearings take wheel movement load and the elements which has to be higher. My XT8 outer wheel bearings always wear quicker and they are the same size.
I found some bearing glue the other day on liquid RC. I was thinking about your problem with the diff pinion gear that by glueing the inside face of the bearing it may allow for less friction/heat from the inside face spinning around the pinion.
I can't find it now, but I'll post it when I do.
Bearings are rated on a ABIC rating with the higher number having smoother/rounder balls while lower numbers are the opposite. What I've found in the past is that higher ABIC rating bearings run smoother and cause less friction but conversely wear out quicker. My preference is ABIC 3 for clutch bearings because they last longer. I'm not sure what Xray bearings are rated but they claim to be high quality which could mean higher ABIC ratings.
I agree there is bearing issue and it has to be reconciled. I know AVID test various ABIC ratings to find the best balance of speed, fricton and lifespan per bearing type and requirements. AVID bearings are good vale too at $1 US each.
PS. I have 2 full sets of bearings which I rotate every 3-4 races. I clean and relube one set while it's not in use. I hope this helps.
![Smile :)](./images/smilies/icon_smile.gif)