The kit for the 550 is SSY125. The kit for the big bikes is SSY500.


Here is the info for the bearings as measured from mine in stock:

This is the SSY125 kit, followed by that for the SSY500 which fits
the bigger XJ models.

For the 25YM-48Y:

d 25 mm (same as the 650/750)

D 48 mm

B 12.5 mm

C 9.2 mm

T 12.85 mm

For the 30YM-48Y:

d 30 mm (same as the 650/750)

D 48 mm

B 12.5 mm

C 9.2 mm

T 13 mm

Now for the SSY500 (650/750) kit:

d 25 mm

D 47 mm

B 14.5 mm

C 11 mm

T 15.2 mm

For the 30Y-48KS:

d 30 mm

D 47 mm

B 15 mm

C 9.5 mm

T 15 mm



I hope this helps, but you are unlikely to find these anywhere as
they are a custom made bearing as indicated by the "Y" for Yamaha in
the number.


These measurements were taken with a Polish made SIS vernier caliper
with a precision of 0.05 mm.

Interestingly, this indicates that the steering head spindle is the
same diameter for both bikes! If its length is also the same this
means one could swap front ends from one bike to the other. The
steering head on the big bikes is smaller however (47 vs 48 mm) which
makes the different bearings necessary to fit the larger diameter
tube fitted to the smaller bike. Odd isn't it?




Rev. Carlton K. Larsen

Pipestone Valley Parish:

Grace Canadian Lutheran Church
Broadview Saskatchewan

and

Christ Lutheran Church
Kipling Saskatchewan

Phone:
H: (306) 736-8268
W: (306) 736-8356