Gearbox Layshaft Issue?

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Ignition is off in the videos. Happy to film one with the plugs out, but there is no resistance/noise. And once the bike is running, it runs normally.

Agree that there seems to be some issue in the clutch area. I have not had a chance to open it up yet but am curious if I will see any damage. At this point, I would love to find some damage because that will point to the cause of the problem.
 
nomadwarmachine said:
Had the Norton for almost 10 years. No issue with kicking before it was completely rebuilt -- inc. motor & gearbox -- and when it starts it runs like a top. The strange lock up did not happen for the first 2 months after rebuild and then it crept up and increased. I began to think that it had to do with the Boyer Mk3, so I replaced with a Pazon and still have the same problem. Thought it might be a little advanced, so I retarded a few degrees but to no effect.

My kickstart procedure remains just prior to TDC and then a swift motion through the kickstarter. Before rebuild and 2 months ago, it was a quick and easy procedure. We will see if the problem remains once I have shimmed & reassembled.

I am 170 lbs. Never had a problem before.

What do you associate with "compression lock"? It sounds exactly like this problem but I have not seen much about this issue elsewhere on the forum.
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" The strange lock up did not happen for the first 2 months after rebuild and then it crept up and increased. "

Carbon build up has increased the compression.
 
Carbon build up seems unlikely given that there are only 200 miles on this bike since rebuild, but nothing is impossible.

Dissembled the clutch and made another video (below). No signs of damage whatsoever. Has anybody ever had an issue like this -- kickstarter jamming in place with what almost feels like kickback w/ignition off and the plugs installed?

Will take another video of motor rotating freely w/out plugs once clutch is reinstalled and the belt readjusted.

 
In the last video, the last kick, you can see the crank did not turn. The belt must be jumping. I cant believe I am seeing this, Maybe its my eyes, but that belt is far too loose. I suggest adjusting it to the correct preload according to the instructions. Turning the belt through 90 degrees sounds like utter bullshit to me.
 
From RGM fitting instructions (though, yes, I know it's Norvil) : 'check belt tension by rotating belt firmly between finger thumb, 70 to 80 degrees of rotation each way being there or thereabouts correct.'
Their proviso that this should be at running temperature too...
 
Stripping the clutch was a waste of time. There’s nothing in there that can be causing this.

As concours has said, I believe the ‘locking up’ as you put it is simply compression.

I believe the ‘kick back without ign’ is the slop in the belt. As already established, it is way too slack.

And I believe the ‘clicking noise’ is your clutch basket rotating very slightly counter clockwise after you realise the pressure off of the kickstart as can be seen in the second of the first batch of videos you uploaded. This is the only ‘mystery’ to me, personally I don’t know what that is, or whether or not it’s even normal.

Concours also has a point about your technique, you are trying to ‘kick’ it, but really you should be aiming for a long, follow-through ‘swing’ on the starter. It ought to be called a swing starter really !
 
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“Has anybody ever had an issue like this -- kickstarter jamming in place with what almost feels like kickback”

I weigh 240, and my 850 will occasionally do that while rolling it over to find TDC
 
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Fast Eddie said:
“Has anybody ever had an issue like this -- kickstarter jamming in place with what almost feels like kickback”

Heck yeah (I‘d overdub some Benny Hill music if I knew how)...

Click to expand...

Orthopedic Surgeon’s dream of this stuff.
 
concours said:
The sideways twisted knee thing...
My meniscus hurts watching it.
I better understand now why so many injure their knees kick starting.
Click to expand...

My main fear, due to the effort required, was something snapping mid kick. But it is 920cc with 11:1 CR...
 
nomadwarmachine said:
UPDATE: I disassembled the gearbox, inspecting everything, and reassembled with the proper play in the kickstart shaft. No change. The kickstarter still locks up near full compression -- even with the ignition off. The transmission is in neutral, and the rear wheel turns freely.

I took a couple of videos from both sides to illustrate the issue. The sound is more like a starter on an old auto that is already running. I suspect that there may be something amiss in the clutch, as Ashley pointed out. The motor turns absolutely freely and runs perfectly when started, but this issue has become progressively worse -- suggesting that there may be something wearing in the clutch assembly (new Norvil basket for belt drive w/Barnett plates), which I rebuilt along with the rest of the bike.

Any advice/ideas welcome:



Click to expand...


In the second vid just before you stop filming, it sounds to me like the belt jumped 3 teeth, my belt is very close to the alternator posts and if it was loose enough to ride over the teeth, I think it would be trapped between the pulley and the alternator posts.

I vote the loose belt is the problem.
 
storm42 said:
In the second vid just before you stop filming, it sounds to me like the belt jumped 3 teeth, my belt is very close to the alternator posts and if it was loose enough to ride over the teeth, I think it would be trapped between the pulley and the alternator posts.

I vote the loose belt is the problem.
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Good spot Ralph, it does sound like that!
 
Have you checked the timing with a light? You said you installed a Pazon and static timed it. I've installed five Pazon Surefires and have found if you set the static timing with the dot in the center of the hole and the alternator line on 31 that they are always too advanced when checked with a timing light. The last few I have set the static timing at 28 and when you put the light on them they are almost reading spot on 31 at 5000 rpm. You could retard the static timing a few degrees but either way you really need to get a light on it as soon as possible. Can't say if this is all of your problem, the belt may also be causing problems but too advanced timing will cause kickback along with some other undesirable things like preignition.
 
bill said:
see post 31 and 35
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Bill, I agree there has been violent agreement the belt is too loose for a long time now. I am really wondering why the OP hasn’t responded and corrected this.

But I said ‘good spot’ to Ralph as I don’t recall anyone previously actually hearing the belt jumping as it appears to do at the end of the second clip.
 
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