Knocking / rattling inside primary drive case + backfire

M-Hawk said:
Yep - parts have now arrived. I'll be making a start this afternoon.

I'm going to re-read the entire thread, make notes and take my time :)
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That's a really good idea. A properly set up primary allows for a sweeter Commando.
Starting with the gear box, observe the main shaft alignment parallel with the crank. There's movement there.
On to the inner cover, you'll find a little movement in the placement of the screws.
I try to align the cover to center on the mounting stud. Set shims or gaskets as necessary for flush fit.
So on and so on...

Edit..you must posted while I was typing. Yes, straighten that up and things get better.
 
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Not only are there no centre stud shims, but I was also missing 2 off washers 60.2322

Luckily I ordered them suspecting they would not be there :)
 
M-Hawk said:
Mini update - before even loosening the inner primary case, I noticed that the centre stud isn’t centrally located around the case. This made me suspect a lack of shims on the clutch side.

Sure enough, after removing the inner case I found 1 x gasket, but no shims. I’m hopeful that correct shimming will straighten it up and resolve the stator alignment problem.

The inner case bolts only had blue thread lock on them by the way, and were not difficult to undo.

More updates in a bit..

View attachment 103702
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Try to center the center stud when you put it back together, but don't fret over it. Procedure: Before installing the three bolts, loosen the nut on the other end of the center stud, remove any shims, install and snug well the three with one gasket. See if you're hitting the swingarm, and if so, install two gaskets and snug the three well again. Snug the center stud trying to center it. Measure the gap to the center stud and record. Three out again, put shims on the center and put it all together with something to seal the threads of the three, especially the lowest one. When all tightened, bend the tabs. Make sure the center stud is tight.

BTW, the parts drawing seems to show shim(s) on the center stud between the inner and outer primary covers - there should be none there - they go between the stud and inner cover.
 
With 2 standard washers on the centre stud the inner primary case looks to be about 8mm clear of the swing arm. Seems excessive, unless I’m measuring the wrong bit.

Knocking / rattling inside primary drive case + backfire
B2AB2DEC-9FCD-4CA9-99A0-FDD735E4B943.jpeg
 
You need to measure it with the centre stud removed as explained by Greg.

Doing what you’ve done doesn’t tell you anything, the cover could simply be being ‘forced out’ by the centre stud. And if it is, it will be distorting things.
 
They way I did it was to start with no shims but with the 2 standard washers and the gasket in place between inner primary and the crankcase, did the 3 mounting bolts up tight and then used feeler gauges to check the gap between inner primary and the centre stud. I then put shims in to match the feeler gauge but only did the 3 bolts up finger tight, pushing hard on the inner primary by the 3 bolts I used my second hand to see if I could get the inner primary to rock in 2 planes (front to back and top to bottom) and adjusted the shims until the inner primary was just rock free in both planes.
 
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M-Hawk said:
With 2 standard washers on the centre stud the inner primary case looks to be about 8mm clear of the swing arm. Seems excessive, unless I’m measuring the wrong bit.

View attachment 103705View attachment 103704
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The swingarm has already dug a slot into the inner primary! Take the inner primary off and look what I mean - where the circle depression is, it should be flat. Hard to tell in the picture, but it looks like the clearance would be zero except for the dub depression with one gasket which would mean that the cover was un-shimmed at some time in it's life and forced into the swingarm. Looks like two gaskets is correct if the stud is not touching the back of inner cover and the three bolts are tight.
 
Tornado said:
How about adding the the DynoDave clutch rod seal while there? Helps/eliminates GB fluid from migrating out and onto clutch plates.
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Please take as constructive! When you say things like this, especially to new people it would be helpful to say more including where to get such a thing. There's no reason to expect that a new guy will know what a "dynodave" is!

You can get some info here but cannot buy: http://atlanticgreen.com/store.htm unless you buy 5 or more. At the bottom that are several dealers listed who may sell one.
 
EstuaryBoy said:
Some here would have you put 50p in the swear box for that!!

:) :)
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Yes, I know, and a thousand apologies to the forum members but I believe Norvil Motorcycles are the only UK source for the Dynodave pushrod seal. Hence, circumstances dictate that one must occasionally throw caution to the wind and buy from The Bearded One!

RGM used to do their own version but I can't find it on their website unless I've missed it, besides, I bought one many years ago and it didn't fit.
 
EstuaryBoy said:
Some here would have you put 50p in the swear box for that!!

:) :)
Click to expand...

L.A.B. said:
Yes, Norvil in the UK.
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Not sure Dave really wants to sell them! I tried all dealers, including Norvil, and found none that I could navigate to a price. So, I tried to figure out how to order a batch to resell from Dave. There may be a way but I don't have the time to waste trying to figure it out. I suppose I could really light a fire and get some from Matt to resell - Dave's head would explode if I did that and announced it here :)

Dave, if your head is exploding right now, tell me how to order - forget wire transfer - I'm in the backwards USA and that way is more trouble than interests me.
 
L.A.B. said:
It seems go to through to the checkout for me but at £34.50 inc. P&P I'm glad I don't need one.
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Holy Crap. I sure don't need one! I'm not even convinced that they are needed at all and that would be almost $50 delivered. They make some sense to me for belt drives. I've always greased the pushrod in Triumph (Not Trident) and Norton and have never seen a problem. When I install cNw e-start, one is included so I install it.
 

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