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Feels like the first tooth has gone on my KS, Does not engage till half the way down,though a little push round and then a full stroke appears. These gears are very thin on the ground , I would like to find one before I pull the bike appart but don't know exactly what they look like and if are different to the 4 speed ones ,any pictures of a 5 speed , no of teeth etc?. If they really are as rare as they seem I am in contact with someone who will make a batch if there is a demand. 5th gears are also iffy I hear.

Hi Bob. I have just rebuilt my narrow case 250 and although I know the kickstart gear is not missing any teeth and they appeared to be in good condition it too sometimes misses the first tooth when starting. I have found it needs a little nursing into engagement when pushing down the kickstart.
I am not sure, but I think this is a design fault with the springs which pushe the quadrant into engagement. Probably why the wide case engines had a redesigned kickstart.

You could be right Jeb as sometimes all appears ok.

This subject has been explored in some detail: viewtopic.php?f=3&t=1703&p=12429&hilit=kickstart+gear#p12399

Matt

Thanks Matt, There is reference to 2 types of 5 speed Narrow case set ups, any idea what Bob was talking about? .

Didn't read the whole topic but I know there were two types of spring used to push the kickstartgear into the gearboxgear.
First type was a Y-type with a little bend in the upper parts.
Second was a ordinary coil with a special "bridge" over it .
Nothing interchangeable, but with a bit of drilling, tapping and screwing the second can be adapted.
Sorry, no pics readily available.

ciao
ducadini

Bob made reference to 2 types of 5 speed gears ,thats the issue. Need to know what the differences are as these things are now hens teeth and just as fragile!

Bob,

I don’t recall incompatibility among 5 speed NC starter gears. But it wouldn’t surprise me. Perhaps I’ll get the chance to look through some kickstart gears in the next several days. I'd like to know if there are differences with the 5 speed.

From my experience, the most problematic transmission gear is 2nd on the clutch shaft. Most have the engagement dogs rounded/chipped because the gear teeth are cut across the dogs. The diameter of the gear is so small that there is no way to machine the gear teeth without also compromising the engagement dogs.

5th gear driven is weak because dog engagement is by slots in the gear. I’ve seen (rarely) these gears crack and could lead to the gear breaking up. The flaw was resolved in the widecase design by replacing the slots with engagement dogs. This required that the transmission shafts be lengthened, one of several differences between WC and NC transmissions.

Matt

Thanks Matt, It may be some time before I get inside again as I have plenty more pressing issues but its good to know what to give a close inspection or even get crack tested. I had the bike out on Sunday and it went well , I'm experimenting with a head camera and hope to post some vids .

After much deep thinking, I remember that behind the KS gear there is a ramp which is part of the engagement process.I remember that there was some wear . Is this item replaceable?, it could be built back up with welding presumably.