Gearshift pawl problem

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I'm in the precess of reassembling my gearbox and have hit a problem.

This is the bit I'm talking about:

Gearshift pawl problem


This shot does not show the problem because of the perspective, but demonstrates quite nicely how much water/condensation there must have been in the box at some time!

The gearshift pawl is not making contact with its spring and so will not move to engage with the ratchet:

Gearshift pawl problem


Gearshift pawl problem


The pawl is new, purchased from RGM and I suspect, like some of the other stuff I have bought from them, is not quite to spec. I have not had the chance to compare it with another pawl - I chucked the old one and can't get to Norvil (just up the road from here) until next week to do a comparison.

I seem to have two options. Either grind out the spring indentations in the gearshift stop plate to bring the spring closer to the pawl, or to wait until I can replace the pawl. Of course, because the bike was a real 'bitsa', the stop plate could be wrong. I'd have thought this unlikely, given the age of the design of the box. I do know that original pawl and spring were in proper contact. However its a 31**** box, but contained some gears from pre Commando days!!!

I would be happy to grind out the stop plate indentations, but do not know how critical the spring pressure or equal spring pressure is to correct operation. Also, can anyone help me out with a measurement across the widest part of the pawl so that I can compare it with mine?

Cheers, Bob
 
Thanks for that. Memory obviously not what it was - I can now recall being concerned about the same thing when I rebuilt my old Norton's box about 20 years ago. I have just put the gear lever on to move the pawl (instead of me pushing the ratchet) and it all came flooding back!!! What an idiot!

I guess the old spring was touching because it had worn almost through. I expect I ought to apologise to RGM, but their lower shocker bolts are still too short to go all the way through the nylock nut and the engine drain plug still has the wrong thread.

Thanks for the link, I actually used their notes for the strip down and rebuild, and have found the parts diagrams invaluable for checking assembly order and the like. Except for the gearbox and forks, the bike was in bits when I bought it, making reassembly more of a challenge.

Cheers, Bob
 
No worries :-)

I suppose I'm lucky in one respect, I've had commando's for 25years, but never a "standard" one, either featherbed or seeley, but never a "rubber"one! Engine and gearbox the same, buteverything else is freeform :-)
 
Some owners may not be aware that the pawl spring needs to be checked and adjusted occasionally, or when new parts are fitted.

If I remember correctly, Mick Hemmings said in the NOC gearbox rebuild DVD that the spring legs can just be in contact with the pawl, so that the pawl will start to move immediately the ratchet mechanism begins to move (I've lent my rebuild DVD to somebody, so I can't verify exactly what Mick said, at the moment).

The NOC Service notes also say that the pawl spring "...must....either touch or just clear the pawl..."

It is important however, that the spring is set so that the three ratchet mechanism pivots are all lined up when the ratchet mechanism is at rest.
 
I have a similar problem....at rest and on its own the end of the sping legs just overlap each other. When its all together the power of the spring forces the pawl at an angle. I realise the legs should only just touch the ends of the pawl but that isnt happening at present. Attempts to bend the legs hav failed obviously because they just spring back. The spring is the correct way in ie straight leg towards top of cover. A present it will engage on downward pressure but on the upward movement it misses the first notch..:( getting the cover on is fun as well. NOT
 
I've had 3 go bad out the blue and struggled with the puzzle while still depending on manual to finally have a down and dirty get er done and get on with it way.
Only two things I pay attention to now, 1. dog leg goes down, 2. get the spring legs parallel in the section the swivel thingy passes by and don't sweat getting it as close as manual and definitely not touch pawl to interfere with its freeswing. '

As you see much of the area sits below oil and there nothing to splash it up so for the next guy inside might consider thick grease or a clear coat of paint. You know what area needs it now.
 
I see what you are saying but with mine there is no way i can set it up so the spring clears the pawl. Its driving me crazy right now!
 
Adrian1 said:
Attempts to bend the legs hav failed obviously because they just spring back.

Have a few more weeties and try again - with more gusto this time. They are a bit hard to bend because they are spring steel but they will bend.

Locate the point where you want the bending to occur and use two pairs of pliers - one each side of that point.

Bend each leg as required so that there is minimal clearance to the pawl each side when at rest with all the pivots in line.

Cheers
Martin
 
Adrian1 » Sat Aug 03, 2013 7:40 pm
I see what you are saying but with mine there is no way i can set it up so the spring clears the pawl. Its driving me crazy right now!

Gosh those are such healing words to me Adrian 'cause its been me before and will again. Sounds like you will have to spread the spring which tends to bow its legs and too wide a gap so then must diddle the legs back so at least the sections the pawl swings by are parallel. Of course as i've found its entirely possible by that point its a gonner, lost its springyness from age and your own little bit extra work hardening. I think its getting time for me to get another spring on hand myself and kick the still perfectly good one out before it drives me ...

hm I'm getting stuff together for cyro tempering, maybe should toss a couple these frail springs in too.
 
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