New to me 56 Domi 88.

The parts book lists the same number for the halftime pinion key and the camshaft sprocket key -
E3683
There is no listing for the dynamo sprocket key .
The exploded drawing only shows the halftime pinion key .
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New to me 56 Domi 88.
 
Interesting. The later books and RGM call for part 000572 as the key used. The E3683 doesn't show up. I used to have one of those old number new number books not sure what happened to it.
 
Interesting. The later books and RGM call for part 000572 as the key used. The E3683 doesn't show up. I used to have one of those old number new number books not sure what happened to it.
Yes - new number/ old number makes things confusing- constant challenge when I did my 1950 ES 2 some years ago.
 
Well things are getting more and more interesting. I found the correct woodruff key for the cam on my Dominator project.
It fits the cam with no problems, but it is too big to fit into the cam gear/sprocket. I am thinking that sometime after 56 Norton changed the size of the key. I have a friend who is a machinist who can machine off a little on each side of the key. Anyone have information of the cam/gear/key thing?
I've just dug the items out of my spares bin and measured them-

keyways for all cams, dynamo drive and non-dynamo drive sprockets are all the same size - for nominal 1/8" woodruff keys.
 
I used a later Norton parts book and RGM's web site to ID the woodruff key. The 56 Model 88's have a dynamo or as we say a generator. The cam sprocket has a gear attached to it to drive the dynamo. The key fits the cam that came with the project but not the sprocket/gear. So, something has changed, and I don't have an earlier Norton parts book. I have one coming by slow boat from NZ.
Keep forgetting about the dynamo. Here’s something on part numbers that may help?

 
I've just dug the items out of my spares bin and measured them-

keyways for all cams, dynamo drive and non-dynamo drive sprockets are all the same size - for nominal 1/8" woodruff keys.
There is no reason for this, but it is what it is. I had purchased a 1/8 woodruff key and I took the cam sprocket/gear with me when I did. It was a very snug fit. Took it home and it was loose in the cam. Dug out the 000572 key and it was a snug fit in the cam and a no go in the gear.
 
There is no reason for this, but it is what it is. I had purchased a 1/8 woodruff key and I took the cam sprocket/gear with me when I did. It was a very snug fit. Took it home and it was loose in the cam. Dug out the 000572 key and it was a snug fit in the cam and a no go in the gear.
II went back and measured all the keyways with my calibrated equipment.

cam keyway measured width -
88 well used 0.130"
daytona well used 0.130"
factory domi special * 0.125"
commando grass track outfit race cam 0.126"
dunstall domi cam * 0.129"
new 2s 0.1245"
new commando std cam 0.125"
(* all 3 keyways measured)

sprocket keyway 0.1275"
sprocket keyway (dynamo) 0.127"

My findings are that -
well used cams tend to have worn keyways
the dunstall cam had oversize keyways from new
factory cams had 0.125" keyways
sprocket keyways are slightly oversize and do not wear like the cams owing to a greater contact area or harder material.

My conclusions -
If the sprocket will not fit on the key check for burrs or other damage/contamination on the key or keyway. if no damage is found carefully dress the key to just fit in the keyway. Do any filing well away from the engine. (A thou or 2 is not going to upset the timing.)


I recall that the last key I used I made from a bolt shank (grade 8.8 is perfect, not stainless steel) to fit.
 
I should have known better. I went to slide the clutch push rod into the main shaft and it went in a little way and stopped.
The transmission was assembled when I got this project, should have inspected it before installing it. The main shaft was bent!
So, I stripped the gearbox and found some blue goop inside. Everything came out and I cleaned everything. That stuff was even inside the detent plunger. This has been an adventure.
 

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I should have known better. I went to slide the clutch push rod into the main shaft and it went in a little way and stopped.
The transmission was assembled when I got this project, should have inspected it before installing it. The main shaft was bent!
So, I stripped the gearbox and found some blue goop inside. Everything came out and I cleaned everything. That stuff was even inside the detent plunger. This has been an adventure.
No good deed goes unpunished…
 
Well, I got word from a machinist friend whom I sent both the sprocket/gear and woodruff key to. Got word back last night that it was all sorted out and that the key fits as designed. He says that the keyway was tapered front to back which explains why the key didn't fit. He filed the keyway and cleaned it up. The parts are on their way back and I should have them early next week. The why still has me puzzled as I was thinking this was the original part.
Report to follow.
 
Got the cam gear and woodruff key back Monday. Installed them yesterday. Progress being made.
Spoke to the guy who traded it off to my friend for Panther parts. We talked for about an hour about the bike and where it came from.
Indonesia is where it was found. Went to the Motorcycle Museum in Vanderpool Texas where he got it.
 
One step forward two steps back. The standard pistons felt a bit tight in the new cylinders, so I took both over to a local machine shop.
They measured the pistons and the cylinders and yes by the numbers in my cope of Modern Motorcycle Mechanics they were tight. Now this got me to thinking about the new cylinders. 1) where did it come from and 2) who made them.3) why weren't they machined to spec?
So, I got the cylinders back and with the rings in place they were still very tight. Standard bore is 66mm and using a digital set of calipers they measure 65.58mm. So, back to the machine shop they go. I'm glad that they honed them tight than too loose that's for sure.
 
Well, the top end is on the Domi. The oil control rings came with an expander which I installed, that was the issue. Removed the expander and it went together with no problems.
New to me 56 Domi 88.
New to me 56 Domi 88.
 
With the expander in place the oil control rings wouldn't compress and the piston was stuck at the bottom of the bore.
 
hello...
you should check the piston's ring depth and width as your oil control ring needs a deeper depth, they made pistons with ,i think 2 different depths, if you have hepolite pistons i would use hepolite rings ,there are some smart people on this site that should be able to point you in the right direction.....hope this helps...
 
I got some advice to lengthen the spring using coins between the coils. Bend the spring forward, install coins, bend backward, install coins, etc... Sorta worked, but only in conjunction with installing the spring then the pivot bolts.

Obviously, the shortest distances are at fully extended and fully retracted so wrestling it into place with a pry bar of some kind (wooden hammer handle?) at those positions works best.
Being tight due to my Scottish side, don't use coins use rusty old washers. Money is flat for stacking and you can't do that if it's buckled.
 
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