- Team Yokomo YZ2 - Fitting a B-Max Rear End -

By Trevor Hale

The YZ-2 with the B-Max rear end moves the motor and battery back around 25mm, giving more rear end grip but still more steering than the B-Max2. If you have a B-Max2 and are happy with it, then please stick with it as it will still work well in all conditions.

I know the set up worked really well for the guys at the euro's, on a low grip clay track. But this was done for some of the lesser talented YZ-2 owners. Who found the YZ to be too much on certain tracks, with differing surfaces and grip levels not been consistent around the full lap. Should also work well over the Winter months when grip is down.

You would need a complete B-Max2 gearbox, which could work out expensive buying the parts separately.

I think this image shows most the part numbers needed, unless anyone can think of any other parts. Some of the parts are the same as YZ-2, but it would be better to be able to swap from one gearbox to other easily.

Converted my YZ-2 to the B-Max2 gearbox using parts obtained from Fibrelyte. Although this set up is for low grip situations, people may find it useful over the Winter months and where tracks have variable grip levels around the circuit. Swapping from one gearbox to the other trackside, takes less than 10 mins.

Consists of:
Battery Brace 2.4mm
Rear shock tower 4mm
Shock tower spacer 3mm

Work involved:
Drilling two countersunk holes in chassis where waterfall fits. This was done using old B-Max2 chassis as a template.

Fitting a 2mm spacer between waterfall and chassis, this could also be done using washers. Some people may wish to go 3mm if your lipos are a little fatter.


Fitting a 2mm spacer between rear camber support and gearbox lug.


The B-Max2 forward/rear hinge pin support fits straight on. I opted to use the one from the YZ-2. Which will need a small amount of filing, to get the full motor travel on motor plate.


A small area needs to be removed from the plastic chassis sideframes, for battery placement.


The wing mounts need 2mm removed to correct angle of wing when fitting graphite shock mount. If using the plastic shock tower from B-Max2, then cutting is not required.


On the bottom corners of the carbon shock tower, a small angle will need to be filed to clear gearbox casing. This is something Fibrelyte couldn't do themselves, but is an easy operation with just a few small strokes of a file.


You could opt for the plastic shock tower from the B-Max2, but the carbon tower gives an extra shock mounting hole. Holes 1, 2 & 3 are the same as the YZ-2 and holes 3 & 4 are the same as the two inner holes on the B-Max2.

Part No. Description Material Type Retail Price in Sterling for carbon parts.
YZ2 01 Shock tower (Trevor Hale design) 4mm 10.95
YZ2 02 Shock tower spacer (Trevor Hale design) C 3.50
YZ2 03 Battery brace (Trevor Hale design) B 12.50

Source:

T. Hale