XRAY - Model racing cars

I got some questions and hoping some can answer.
Why make the diffs bigger, its like having three huge gyros inside the car. When xray at the same time recommend plastic for the xb4 too reduce mass rotation?

Xb8, XB9, 808, I hade them all, and last year I got back to Kyosho, and there is no other car that has a driveline like the MP9. Small diffs, alugears, universal swing shafts. Its smooth as hell.

Driving the old xray cars feels like driving an electric car with dragbreak. Driving the MP was totally different, it rolls fantastic.
With this new driveline in the new XB8, bigger cvd, larger pinions, diffgears, I fell its the wrong way to go.
Still with the cvd, U got a big bearing and small bearing at the hubs. Why not 8x16 bearing all the way?
When U guys were testing, what made U go the way U did and not makeing the driveline lighter than the old ones?

Looking forward to getting this car as soon as possible

Whut?

Never noted any of that with my car. Rolls as well or better than any Mugen or Kyo I've driven. Sounds like a build problem. Diff shims? Bearing lube? Gear mesh?

i too would also like to know how the bigger crown and pinion gears improve the car,i always beleved
smaller and lighter was better.

First of all, the K-cars run free as heaven! I had one. But if the drivetrain on my previous Xrays (XB808'09,'11, XB9'12) is warm after one or two laps there's not a big difference. Between the XB808 and XB9 is a huge difference already. You have to consider that K-cars use cardan shafts and metal shielded bearings that run super free but require more servicing than rubber sealed bearings.

Now to the spurgears: A smaller spurgear with a bigger bell reduces the wear on the central driveline as more torque is generated after the central driveline but eats much more power as the whole central driveline spins faster. So a bigger spurgear with a smaller bell makes the car much more crisp, more responsive on the throttle. Also the cornering agility is better then.

The new XB8 has a very straight central drivetrain which sure makes it running with less friction and less binding.

Why not plastic? Because a 1/8th buggy is not a 1/10th lightweight. The XB8 diffs are not bigger than on previous models refering to part numbers.

I think there was a small mistake in the presentation where it said that the diffs would have 46T gears and 14T pinions.

thanks robin can you please check on this as from diffrent sorces
i have read 46t crown gear 13t or14t pinion and 46t spur gear and
13t or 14t clutchbell.

The new XB8 is using 46T crown spur gears in front and rear, 46T center spur gear and 14T pinion and 13T clutchbell.