How To Remove Inner Timing Cover

Moderator: minetymenace

Forum rules
Please write in easy English so everybody understand.
Post Reply
Posts: 160
Joined: Sun Apr 15, 2012 3:40 am
Location: Peoria, IL, USA
Has thanked: 0
Been thanked: 0
Flag: United States of America

How To Remove Inner Timing Cover

Post by PeoB50 » Sun Jan 06, 2013 11:15 pm

There's some confusion about this that hopefully i can clear up.
You can get into the tranny from the right side, w/o messing w/ the primary side, and do lots of
things as long as the mainshaft is still left in place (to remove the mainshaft you do have to
remove the clutch to get it out).
There are some things easy to overlook trying to remove the right side inner
DSC00909 (800x600).jpg
First remove shift lever, foot peg, kicklever, etc and remove the outer cover and support it gently on something
the right height and size so dont have to bother undoing the points wiring. Tape over the little
clutch linkage ball! pull out the kicklever quadrant.

For the inner cover:
- put engine at TDC on compression (both valves closed)
- remove cam timing cam and mark where it was located.
- remove the pin that the camplate pivots on....use one of the timing cover screws that
is the correct thread to thread into the end iof the pivot pin, and tap/pull it out
- remove the 5 phillips screws (4 long and one short) inside the outer rim of the cover.
- remove two more 3/4" allen screws at the lower forward area outside the outer rim.
bend over and find these....easy to overlook.
DSC00910 (800x600).jpg
- the kick lever spring already fell out but be sure to remove that (1/8"Whitworth) spring
anchor hex bolt that also acts as a cover fixing bolt. really easy to overlook.
- remove the nut (RH thraed) and kickstart ratchet gear assy on the mainshaft. tag wire
the parts in a stack the way they came be safe
- now you're ready to tap w/ a mallet on the outer backside of the inner cover to break it loose.
- be sure to put your thumb or finger on the end of the camshaft to keep it in place as you remove
the cover. you'll need to rock in a bit to do three things at once: fit under/past the exhaust pipe,
pass up and by the lower frame tube, and remain relatively square as it passes over the mainshaft
and camshaft. Sounds bad but its fairly easy as long as the mainshaft bearing is not too tight a fit
over the spline on the mainshaft. After the inner cover is off just fiddle a bit w/ the layshaft and
it wil pull out completely. Just be careful not to lose track of the thin spacer on the outboard end
of the gear stack. Also, be sure to locate and keep track of the small o-ring on the main lube oil feed.
I dont know how to add the cool little arrows to the pics yet. That would help. I'll check into it.
Just bought a borescope to probe thru the layshaft hole to check camplate/camplate detent spring action.
Stay tuned,

Posts: 158
Joined: Tue Apr 04, 2017 9:28 pm
Location: Norfolk, England
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: How To Remove Inner Timing Cover

Post by Victor500T » Tue Apr 25, 2017 10:00 pm

This is great info Tom, especially as removing the inner timing cover is my next job on my newly acquired B50. My manual is nowhere near as clear. If you're still on this forum,please post more stuff like this - very helpful.

Posts: 86
Joined: Sat Oct 22, 2016 5:28 pm
Location: Dorset UK
Has thanked: 0
Been thanked: 0
Flag: England

Re: How To Remove Inner Timing Cover

Post by Ubert767 » Fri Aug 03, 2018 7:31 am

I have successfully used the above advice when curing an annoying gearbox oil leak, all went well but I was having some trouble when refitting the inner timing cover. This was caused by difficulty maintaining the gearchange cam plate and the gearchange quadrant in their relative positions ( in 3rd gear) as I offered up the timing cover. I used a strong neodymium magnet on some twine
to hold them in place until the gearchange shaft and the heel of the cam plate had entered the cover. I whipped out the magnet with the twine just before final closure.
Worked well for me.

Post Reply