The little part with no home

I bet you all think that I’ve been sitting back kicking my shoes off and relaxing over the Christmas period.

Not a bit of it.   I’ve been scratching my head, baffled over a couple of things that I do not know how they go back together.

I have a little tin.   In the tin are things that can loosely be described as “things that came out of the crankcase”.   I label them thus because as I was taking things out of the crankcases I was putting them into the little tin.

I ended up with these two chappies.

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both have a threaded bolt that fits perfectly into the drum with the wiggly lines in it that changes the gear.  Trouble is, there is only one hole and two bolts.

Endless fiddling and trying things in different places and looking at pictures on the internet and I now know what they are.  The bit shaped like a star is called “Cam. gear shift” and the other bit is called “Stopper.Drum”.    The reason that I couldn’t work out where they go is because they are on the outside of the crankcase rather than on the inside. The star shaped bit screws into the wiggly lined drum and the stopper then nestles it’s pretty little head into the star shaped thing.   When you change gear, by some miracle yet to be discovered, the stopper makes the star turn round and thus the gears change.  Simple when you know how!

I’m still very stuck though.   I have the kick start assembly all ready to go in.  I see where it goes and I see that it has some cogs that mesh into the gearbox.  What I don’t see is why bits of the kick start seem to rub against bits of the gearbox and I also can’t see what stops the kick start bits flying randomly around the engine as soon as everything is running.  I am totally baffled by it.   I think perhaps my only hope is to take apart another engine to see exactly how things go back together again.   I fear that this will lead to another bunch of cogs on the floor and another scratching of my head.  If there is anybody out there who has any knowledge of these at all then please drop me a line and give me some advice.

Other than that, once I’ve worked out how these bits go back together it is just a case of reassembling the engine.   It should be fairly easy to do!

Happy new year everyone.  We should be back to normal service now I no longer have to spend every weekend shopping for Christmas presents.

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The glistening gearbox

Other than the obvious religious festival and the giving and receiving of gifts, Christmas is traditionally a time of feasting and as we all know, a good feast relies on lots of cooking.

After leaving the bearings in the fridge overnight to marinade in coldness I waited patiently until the coast was clear and whacked up the heat on the oven.   5 minutes later and with barely a sniff of Castrol permeating the kitchen and the old bearings were out and replaced by new ones.   As it is panto season I had a bit of an Aladdin moment thinking about new bits for old and then another more scary moment as I heard footsteps coming down the stairs.   “She’s behind you!” I thought but oh no she wasn’t.   It was the cat coming to see if there was any potential protein coming her way as the oven was being used at an unusual time.

I had very carefully dissembled the gearbox prior to the oven adventure.    Everything was lined up in the correct sequence, cleaned, placed in the correct place on the clean side of the sink (obviously I mean workbench there, sink is just what I call it sometimes) ready for being rebuilt.

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The way the gearbox works is there’s a big barrel with wiggly grooves in it (you may note that I am being very technical here).   There are three forks, the handles of which nestle in the wiggly grooves and the prongs nestle between the cogs of the gearbox.   When you change gear, the big barrel rotates slightly and the wiggly grooves make the forks lift or drop (depending on whether we are on an up wiggle or a down wiggle) and so the forks make different gears engage together.

I made two mistakes.

As I was carefully laying out the cleaned parts I was not quite so careful about which way round they went.   This wasn’t so bad with the cogs because it was sort of obvious (and I had a picture) but the forks are asymmetrical and I had no idea what way round they went.    I spent a jolly three hours trying them in all combinations possible until I was happy that they were correct and then carefully put everything back in the crankcase – Fellow rebuilders, do not do what the maual says and try to put it all in as a job lot.  It is impossible.   Start with the shafts and then build them up slowly from there.   It’s a bit like tetris but backwards.

This was my second mistake.   After reassembling it all and standing back to admire my clean, mouse-free, working gearbox I noticed the little white bag that contains the new oil seal for it so everything had to come out again to replace it.

In an ideal world we should be joining the cranks together this weekend.   If that happens it means that I actually managed to get my Christmas shopping completed.   Yeah, right.