Broken again

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Replaced kick start pawl,spring and pin.worked fine for 2 rides. Stopped at store kick start would not engage .what did I miss?
 
PJ - one thing I've learned about these gearboxes is...
The spring on the selector shaft has to be bent/adjusted to be absolutely equal clearance above & below to give really good gearchanges.
Attention to this point makes the difference to a lovely "snick-snick" change instead of a muddy uncertainty.
Worth the time and attention here while you've got it apart.
Cheers
Rob
 
What did you find the first time in there? And what did you do while there? Any photos? Might be time to buy the Mick Hemmings DVD. Then stop messing around and tear down your gearbox for a real examination.
 
rvich said:
What did you find the first time in there? And what did you do while there? Any photos? Might be time to buy the Mick Hemmings DVD. Then stop messing around and tear down your gearbox for a real examination.
Click to expand...
...and, at that point, you should probably take a serious look at the potentially bad layshaft bearing. Now's the time to change it (unless it's already been done).
Bad!
Broken again


Nathan
 
Rob, could you elaborate on the spring adjustments to obtain smooth shifts?
Is the spring in question the ratchet spring (04.0038) or the return spring (04.0479)?
My gearbox could use some "fettling".
 
Nater_Potater said:
...and, at that point, you should probably take a serious look at the potentially bad layshaft bearing. Now's the time to change it (unless it's already been done).
Bad!
Broken again


Nathan
Click to expand...

I just had my Portuguese lay shaft bearing replaced at 22,000+ miles. It is is perfect shape. Now I can repurpose it into
a front wheel bearing :rolleyes:
 
know_fear said:
Rob, could you elaborate on the spring adjustments to obtain smooth shifts?
Is the spring in question the ratchet spring (04.0038) or the return spring (04.0479)?
My gearbox could use some "fettling".
Click to expand...
Dean
I meant 040038 - what I understand is called the Pawl Spring (at least that's what the 1961-62 parts list calls - seems to be different for Commandos?)
The information I used was from the Old Britts website - https://www.oldbritts.com/gearbox_a.html
Read the bottom of the page for more detail under the outer cover but the important bit I was referring to above is covered in the following information from the website (I've retyped it as the text shows as unreadably small)

The ratchet spring (04-0038) is bent correctly so the legs DO NOT touch the gearshift paw (04-0024), but there should be just a very small but perceptible clearance on each side.
Broken again

Incorrect ratchet spring fitment. (my comment here - there is far too much clearance so the pawl can flop around)

Broken again

Correct spring fitment. (my comment here - the picture doesn't show the small gaps above and below the pawl - I set at 0.005")

Even new factory springs must be checked. It is very easy to fix a spring with the incorrect bend. Just take a pair of pliers and straighten out the legs slightly. Straighten them out a small bit at a time and keep checking until you achieve the correct fitment.

I was pleasantly surprised at how much smoother the shifts were after paying attention to this detail. Note that it's important that the very small gaps mentioned are equal!

Hope this helps
Cheers
Rob
 
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BTW - I have made pdf files of the Old Britts:
1. Gearbox Checklist (36Kb)
2. Dismantling Gearbox (1.1Mb)
3. Assembling Gearbox (1.9Mb)

..so - too big to post here

I made them so I could have a hard copy in my workshop (no computer).
If anyone would like copies PM me with your email address.

It goes without saying that Old Britts have done the Norton community a big favour in publishing this... and yes, I do buy parts from them.

Cheers
Rob
 
I know you quoted the Old Britts site, but the top photo labeled "incorrect" seems to have the clearance needed, whereas the lower seems to interfere with the pawl.
Are these captions reversed, or is there something else I'm missing?
 
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No Mr Rick - the captions are correct for the photos.

The top one marked "incorrect" has far too much clearance so the pawl can flop around too much.
The bottom photo, "correct", does not clearly show (it's in the text) that there is a slight clearance - it isn't specified in Old Britts info but I set my spring to 0.005" clearance from the pawl.
As I mentioned above it's important that these gaps are equal above and below the pawl.
Cheers
Rob
 
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So I got it wrong twice! Jeez... I'm gonna edit my post.
And Thanks for the clarification, Rob. If they had said "too much clearance" (like you did for the top photo), that wd make more sense.
 
Thanks for the comment Mr Rick - I edited post #29 to save others having the same questions
 
Excellent. Thanks Rob, I'm just about to get my bike back together.
I hope it shifts a bit smoother when I've done this.
 
Right you are LAB, though he may have fixed his kickstart problem.

PJFlynn said:
Thanks for the help on my not broken shifter.
Click to expand...
Click to expand...

I went even further into my gearbox to shim the kickstart shaft and found a badly worn kickstart pawl. I know everyone will say to get a new replacement but I wonder if it's possible to build up the damaged area with a MIG welder and then grind it back to it's original shape.
It's not the cost of the part as much as the wait time to get it. Has anyone tried this?
 
know_fear said:
Right you are LAB, though he may have fixed his kickstart problem.
Click to expand...


I think the "Thanks for the help on my not broken shifter." was something of a sarcastic comment and that he hasn't fixed it.
 
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