Somewhile ago I posted about oil leaking from the rear brake operating shaft in the bevel box, and into the brake drum. (R80ST by the way)
I stripped it down to replace the O rings on the shaft, and observed that the bush the shaft ran in was inserted in 2 parts, 1 in the outer bevel housing and 1 in the inner part.
The oil volume of 260cc (Haynes) put the level above the level plug (why isn't the level plug a bit higher up then?), but also just on the bottom edge of the bush.
This meant that any oil 'frothing' or movement in the bevel box was only contained by the shaft O rings.
I spotted that Motoworks listed a one piece replacement part (Rear brake cam spindle bush in bevelbox D=15.8x84.5 ( Mono / G/S / ST ) | TRA01699)
Great, a solution, but how to get the old bush out, and the new one in.
Take the bevel box off the bike and press out with a hydraulic press.
Something more simple was needed. Can it be pulled out?
Turned up an aluminium shouldered plug, with M8 bore to allow length of M8 studding to be passed through
Cut a length of thick wall stainless tube with a turned face at each end. Will sit 'square' against the plain face on the outer bevel box (The face that the felt bush sits against).
This allows the pulled out bushes to drop into.
Assembled it with nut/lock nut on one end and then couple of thick washers on other end outside the tube with M8 studding.
Warmed the bevel box gently with a hot air gun. Warm to touch.
Success, out came the 2 bushes. The idea had worked.
Now to fit the one piece bush.
Arrrgh....It just fell in. What the heck.
The unexpected result!!!!
What to do?
The old bushes measure 16.03 OD
The new bush measures 15.80 OD (and are listed as 15.8 by Motorworks).
Searched RealOEM for all models using the same technique of the rear brake spindle running through the bevel box. (R80, R80G/S, R80RT etc).
ALL were described as 'Tube 15.8'.
Funnily enough, the length at 84.5 is OK.
Bu**er, bu**er, bu**er.
Why is my bevel box different from anybody elses?
Monday morning down to my friendly precision engineer/toolmaker.
Please turn up a one piece bush like this but.......Thanks.
Later, back at the workshop, warmed up the bevel box and used the same technique to pull the new bush into place.
NOTE. The M6 oil level screw has to be shortened as it will foul on the bush which is now directly in front of it.
Re-assembled the shaft with O rings and HMP grease, adjusted brake, re-filled bevel box, and out for a spin.
Thought this little tale might be useful.
I stripped it down to replace the O rings on the shaft, and observed that the bush the shaft ran in was inserted in 2 parts, 1 in the outer bevel housing and 1 in the inner part.
The oil volume of 260cc (Haynes) put the level above the level plug (why isn't the level plug a bit higher up then?), but also just on the bottom edge of the bush.
This meant that any oil 'frothing' or movement in the bevel box was only contained by the shaft O rings.
I spotted that Motoworks listed a one piece replacement part (Rear brake cam spindle bush in bevelbox D=15.8x84.5 ( Mono / G/S / ST ) | TRA01699)
Great, a solution, but how to get the old bush out, and the new one in.
Take the bevel box off the bike and press out with a hydraulic press.
Something more simple was needed. Can it be pulled out?
Turned up an aluminium shouldered plug, with M8 bore to allow length of M8 studding to be passed through
Cut a length of thick wall stainless tube with a turned face at each end. Will sit 'square' against the plain face on the outer bevel box (The face that the felt bush sits against).
This allows the pulled out bushes to drop into.
Assembled it with nut/lock nut on one end and then couple of thick washers on other end outside the tube with M8 studding.
Warmed the bevel box gently with a hot air gun. Warm to touch.
Success, out came the 2 bushes. The idea had worked.
Now to fit the one piece bush.
Arrrgh....It just fell in. What the heck.
The unexpected result!!!!
What to do?
The old bushes measure 16.03 OD
The new bush measures 15.80 OD (and are listed as 15.8 by Motorworks).
Searched RealOEM for all models using the same technique of the rear brake spindle running through the bevel box. (R80, R80G/S, R80RT etc).
ALL were described as 'Tube 15.8'.
Funnily enough, the length at 84.5 is OK.
Bu**er, bu**er, bu**er.
Why is my bevel box different from anybody elses?
Monday morning down to my friendly precision engineer/toolmaker.
Please turn up a one piece bush like this but.......Thanks.
Later, back at the workshop, warmed up the bevel box and used the same technique to pull the new bush into place.
NOTE. The M6 oil level screw has to be shortened as it will foul on the bush which is now directly in front of it.
Re-assembled the shaft with O rings and HMP grease, adjusted brake, re-filled bevel box, and out for a spin.
Thought this little tale might be useful.
