Sort of a different clutch question (73 Mk I)

My clutch eventually developed drag to the point that it was difficult to get in first gear at a stop. I took it all apart and cleaned it. It uses bronze plates and has no serious indintations in the nose. When I put it all back together, it had a great feel on the lever with no drag or slip and neutral could be found easily with bike stopped and running (appx .015 clearance on the stack). I also used the minimum recommended amount of ATF in the primary.
Not too long after this I rebuilt the head and barrels. Now all of a sudden, neutral is OK to find sometimes and not good other times.
That's sort of the background for my question.
In the book titled The Norton Commando Ultimate Portfolio, I read a Cycle World Road Test titled Norton 850 Interstate (which mine is a 1973 model of). The article is written in December of 1975 and states that on their test bike sometimes neutral was easy to find even when stopped and sometimes neutral is very evasive yet shifting remains normal.
My question is
is this sometimes evasive neutral a Commando trait difficult to remove since it showed up on a 1975 model in 1975, or can it be fixed for long periods of time barring no oil contamination?

on mine neutral is all ways easy to find but and it is a big but i have a DRY belt drive, 5 plate surflex clutch and a push rod seal. after 20,000 miles it still works great

windy

So, element do you think was plaguing the 1975 model in the road test in 1975?

It could be several things. ANY gearbox oil contamination on the plates, primary chain to tight, worn center hub (wears worse with bronze plates)all parts MUST be flat ie no warping on plates.

windy

Is neutral easy or difficult to find when the engine and gearbox are cold? Or do you find it more difficult to find neutral when the plot has reached normal operating temperature? If you adjust the cable so there is almost no free play, does that make a difference? With all standard OE parts, including bronze plates, I find neutral is more tricky to select when everything is hot. A while back, I fitted a clutch lever and lever bracket which gave more lift and neutral was a lot easier to select, but the action was not as nice as the standard lever.

I'll check the hot and cold thing this weekend. I have the recommended slight movement in the right side of the clutch actuating rod and the 3/16 to 1/4 inch freeplay in the cable itself. Are you suggesting that I cut this cable freeplay down to less than what I have? What lever actuator did you use to get the different lever action?

I don't know how helpful this will be, but poor "neutral-finding" is not endemic to the Commando. I have a Mk. I 850, and neutral is always easy to find, hot or cold. I use Redline MTL in the primary and Royal Purple GL-4 gear oil in the tranny (gonna switch the latter out for Redline MT-90 next time around), FWIW.

Afterthought: Are you running a DynoDave clutch rod seal? You might want to try that. Not a bad idea in any event, and MIGHT solve your problem.

Yellow Cad, I'm suggesting that you try reducing the cable free play to an absolute minimum for a very short time, to avoid any prolonged contact between the clutch actuating parts, just to check if you are getting enough clutch lift. I found an aftermarket lever and bracket lying around, of unknown origin, which I made fit and which gave me more lift, at the expense of reach and effort. I know my clutch plates are flat and free from gearbox oil, and I completely rebuilt my gearbox recently, which did not improve or disimprove neutral selection with the standard clutch lever. I'm still trying to pinpoint why I need more clutch lift to free the plates when hot.

It may be that lift is not your problem, but I'm suggesting is that it is part of a process of elimination.

I appreciate that daveh and I'll give the reducing cable freeplay a whirl. What is your stack height clearance? I belive mine is about .015 inch.

Again, the big puzzel to me is related to the 1975 road test describing 1975 Commando as having this same problem. I would love to know what was causing the problem in that case but I guess we never will know that.

With a very little bit of freeplay at the lever and virtually no freeplay where the clutch cable goes into the gearbox, my clutch seems to work OK. No slip, just the tinyest bit to no drag and goes into neutral stopped and running most all of the time. My question is

am I causing any long term damage by running minimal to no free play in the clutch cable on a continuous basis? I am not sure what no freeplay is actually doing to the clutch.

OK, now you know that you need more lift to separate the plates to get neutral. Therefore, it appears that the gearbox is not the problem. The question is: why?

If there is zero clearance, the clutch pushrod will rub constantly against the adjuster screw and the ball, leading to rapid wear of these parts. Until I find out why I need more lift than is normal, I have adjusted the clutch so that there is about 1 to 2 mm slack on the cable at the gearbox at normal operating temperature. As long as the parts of the actuator mechanism are not in constant contact with one another, then it should be OK. I check for slack by pulling on the clutch outer cable at the gearbox. Even just one turn of the cable adjuster makes a difference to getting easy neutrals.

You asked what my stack height is. I can't remember precisely, but I have about 40 thou gap between the clutch stack and the diaphragm. However, I would think that stack height should only affect spring pressure and lever effort.

Is your clutch centre notched? If severely notched, this could prevent the plates from separating sufficiently, causing drag. Mine doesn't seem that bad.

I wonder has anyone else cured drag by replacing the clutch centre?

I went through all this several years ago and found a Dominator operating lever in the inner cover. Unlikely to be yr problem but this gave lots of leverage (light clutch) with reduced travel. PO had been running the cable adjustment so tight the pushrod was dimpled from the ball. Fitting a Commando part didn't totally solve my neutral finding until I checked the diaphragm which had several fingers at different heights (up to 1/8" out)so it wasn't releasing evenly. A new part solved it.
Set your freeplay by turning the adjuster until it just starts to load the pushrod then back off 1/4 turn. Mine won't release cleanly if set by the book. Just make sure when it is all stinking hot that you still have some play at the lever.
You might also have a badly worn operating lever in the inner cover which is not getting you full lift. Unusual but it's possible.

I vote for the primary chain being too tight as Bill mentioned earlier. Most people make these too tight initially or else they don't follow the manual procedure and it tightens up again after riding.

Russ

Dave my clutch center looked pretty good with some marks but no serious notches.

On the primary chain adjustment, I did mine by the manual but I will go back through that one more time. When checking to see if pressure on the final chain would affect the primary chain, I found that pressure on the final chain did not tighten the primary chain but it did slightly move it. Is this getting close to a problem?

Does freeplay in the clutch cable slightly increase or decrease as the bike heats up?

Yellowcad — good question. I need to tighten the cable adjuster when the engine warms up, otherwise neutral is difficult to select. This might mean that there is an increase in cable slack as she warms up, although it's not that noticeable at the bar.

I adjusted my new primary chain very carefully. If anything, it is set very slightly loose, and I checked the play when hot. I have just fitted a new actuating arm with the correct part no. in the gearbox, so I know it's not an Atlas arm.

I'm not sure if I've understood you right, but if you find that pressure on the final drive chain moves the primary chain even slightly when the gearbox through-bolt and adjuster are both tight, then this must be investigated and fixed. Perhaps some other members who have experienced and fixed this can give some advice. In the meantime, it makes sense to fit a primary chain adjuster to the L/H side of the cradle and I intend to do this.

We will get to the bottom of this eventually!

I think it is normal for it to move slightly when the rear chain is pulled. (Mine has always done it anyway.)

The adjuster for the gearbox is not in the most accessible place in the world so I think a lot of people short-circuit the process. I am usually checking the primary chain for the following week or so after making any adjustments and sometimes it does tighten up slightly no matter what I do.

Russ

Yellow cad this web site may well be of help
http://atlanticgreen.com/
I had problems and this site sorted it ,it turned out I had one too many steel plates.