'68 Commando heat sink

Joined
Dec 26, 2007
Messages
230
Country flag
Hi.
Can anyone advise where the heat sink mounts on a '68 Commando? It is the double 4" plate version.

I did not have the benefit of taking the bike apart & don't know where it goes. The 1968 parts book is no help either.

It also seems to me there must be an electrical connection to the sink??

Thanks,
Stephen
 

L.A.B.

Moderator
VIP MEMBER
Joined
Nov 20, 2004
Messages
17,985
Country flag
Do you have the "Zener diode bracket" part 060853?

This bracket apparently mounts the heatsink assembly to the front left-hand corner of the battery tray and is secured to it by a "Rotolok" fastener 060847.

'68 Commando heat sink
 

Ron L

VIP MEMBER
Joined
Feb 27, 2004
Messages
3,111
Country flag
I have never understood this set-up. The only reason I can come up with for the roto-lok is to make it easier to remove when taking the air filter out. However, since you need a wrench to remove the front filter plate, one would think you could remove a bolt for the heat sink!!

Moving the zener to the foot peg mount with the '69 'S' model was one of the smarter things Norton did.
 
Joined
Dec 26, 2007
Messages
230
Country flag
Hi L.A.B.
Thank you for this advice & photo. It's a great help.

I have the bracket & plastic insulator. I will order up a Rotolock

Is there some attachment to the Zener diode?
Cheers!
Stephen
 

L.A.B.

Moderator
VIP MEMBER
Joined
Nov 20, 2004
Messages
17,985
Country flag
I admit I've never seen one of those units, so I'm not quite sure what you mean by "attachment to the Zener"? Do you mean the wire connection?
 

Ron L

VIP MEMBER
Joined
Feb 27, 2004
Messages
3,111
Country flag
Is there some attachment to the Zener diode?

The zener has a spade connection with, I believe, a brown with white wire running from the rectifier to the center of the zener. It also requires a red earth wire from the mounting bolt of the aluminum disc or from the back side of the zener stud to a chassis ground. Do not place this wire between the zener and the disc. Without this wire, the zener will not work as the unit is insulated by the rotolok. Use heat sink compound on the base of the zener before bolting to the disc. It is imperative that you have good contact between the zener and the heat sink.
 
Joined
Dec 26, 2007
Messages
230
Country flag
I like the "amen" & will go the Podtronics route.

Being new to British bikes, I am open to inserting improved technology. Plus, I am sure Podtronics will be less expensive than original equipment pieces.

Thanks & Happy New Year to all!
Stephen
 
Top