Tiger Cub Gearbox Re-assembly Advice

[brucey]

Hi,

I have just finished building my Armac Cub.  During running it in I noticed I had a small oil leak from the inner gearbox case.  I removed the outer and inner RH cases to re seal it and reassembled everything only to find I couldn't move the kick start or select more than 2 gears.

I have now removed the covers again and realized I hadn't put the lobe on the kick start shaft at 6 o'clock which would explain why that was jammed!

Before I put the side back on (for the 3rd time!), can someone just clarify what I need to do with the selector plate, selector forks, indexers and gear clusters.  

I understand the need to position the selector fork guides into their respective slots in the selector cam plate but where should the outer profile be in the spring?  I'm assuming second notch in (neutral?).

If the above is correct, then where should the 2 gear position  indents be in the rectangular slots in the cam plate?

Believe it or not, I have assembled at least 3 Cub gearboxes but I usually do them with the engine out of the bike and laying horizontal in an engine stand.

I seem to be suffering the same crisis of confidence Tom Cruz had in Top Gun!  I'm hoping it will all turn out good like it did for Tom and I'll be riding my leak free Cub off into the sun set sometime soon!

 

Any help and advice appreciated.

 

Bruce.

Edited September 15, 2017 by brucey

[brucey]

To answer my own question;

Put the kickstart lobe at 6 o'clock (facing down)

Make sure the Cam Plate is in roughly the right position and the spring plate is located in an indent.

Make sure the selector guide rollers are in the correct cam plate grooves.

Dry assemble (no sealant) holding the gearbox cover on with the 2 big screws.

Note: The cam plate will sort itself out when you put the pin in.  It is also easier to put the split pin into the selector pivot pin if the bike is in 1st gear.

Check kickstart moves and engages and gears select (mine were both OK second time around).

Remove cover again, apply sealant to faces and reassemble.

All seems perfectly simple now!

I'm trying some sealant as recommended by Chris at Meriden.  I applied a thin layer of this to both faces.  I'll let you know if it cures my slight oil leak.  I'm assuming the chamber where the oil pump is gets engine oil in there which then drains back into the crank case through a hole near the bottom of the crank case.

If I still have a leak I may need to use different colour oils for the engine and gearbox to help identify where it is coming from.  I'm running a dry diaphragm clutch so no oil there. However, I'm pretty sure it's sorted now.

I hope this helps someone else.

 

Bruce.