Chassis

my personal how to .

done at dozens of standard (hanging) forks but not at usd /standing forks yet, but it should work same way

best done when changing fork oil ;-)

as a "little" add to "how to secure the fork is 100% straight in yokes / clamps"

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intro:

the (following) basic scheme is the same for both types of fork (standard - standing / usd - hanging)

especially if you want to change the oil anyway

fork out

Empty the fork completely

put the fork back in

wheel on

move fork including wheel up and down

et cetera

however, this work is only necessary once, if at all, because the fork legs never twist in normal use.

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1. to put the busa on a "middle" stand like this (rod goes through swing arm axle)

made of simple 1" steel pipe and two short 1/2" (horizontal) pipes plus a strong, non-bendable 12mm steel rod (e.g. 42CrMoS4) 650 mm long

(all dimensions see here)

then 2. "getting" the busa´s front wheel 1 inch free of contact to ground by

2a. car lifter / jack under exhaust pipes like this

or

2b. chain hoist, fastened, how ever (by a belt?), at the front frame like this

3. taking out the entire fork

PLUS loosen the 32mm head nut at upper yoke

completely disassemble the fork 

then assemble the fork again - thinly oiled sliding rings / bushings

but without 

- springs ,

- all inlays,

- caps,

then put the empty fork back into clamps / yokes

then monting the wheel with its only softly hand tightened axle/pivot 

then a thin board under the wheel and move the wheel up with this board

by this you see immediately if the fork does its work fine or if it stucks somewhere on its way up and down

forced by the weight of front wheel it should "fall" down absolutely easy

if it doesn´t fall that easy move the wheel a 2nd / 3rd / 4th time with the board up until everything moves easily.

(by that the fork "legs" itself turn a very little in the yokes and become parallel / straight)

then tighten the top nut to around 40 Nm 

do the trick with the board again to control the easy up/down moving of fork

if yes, you can put out the fork again

fill it with all yet missing parts and oil

and put the fork again back to yokes and tighten the yoke´s bolts

all 6  to  23 Nm (gen1)

and tighten head nut finally to its torque of 90 Nm 

reassemble all other parts to the fork and be happy.

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so far my theorie !

 - remember - i didn´t do that work at a usd yet - this text here is a kind of derivation of the work on dozens of standard forks

so - if someone follows my description and finds a fault please tell me ;-)

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edit:

if you´re going to straighten the fork
change steering bearings same time from ball to tapered bearings

BEST change you ever made !

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some other torques at the fork

the M10 "ALLEN" bolts - 40 Nm

wheel axle - 100 Nm

its clamp bolts in fork´s "fist" - 23 Nm

calipper´s bolts - 35 Nm

fender´s bolts - 8 Nm

shaft´s nut & counter nut at tapered bearings :

between the upper yoke and the frame head

 - the lower one once 30 Nm, then loosen and tightened again to only 3-5 Nm

 - its upper (counter) nut 50 Nm