And what did we buy today?

Our MX5 Miata bought a $1,600 crank key.

We left him for a timing belt. The shop called and said the keyway was all wallowed-out, that this was a thing on the first-year production. Basically the crank is too short. I think this engine was used in the economy 323 then turned frontways and fitted with a gussied-up valve drive and a nose pulley longer than the crank nose. Eventually it gets to wobbling real bad. It can shear the key and then the jumping pistons smack into stuck-open valves, no fun at all.

For more fun, this car is NOT a snow-car: too low, summer tires, excess pep at low RPM. And it has snowed every other day. Not enough to stick the bigger vehicles, but the Miata has been stuck in less than this. We called the plow guy, rather than risk getting the Miata onto the garage slope and get stuck blocking everybody.
 
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You cannot repair the key way on the crank?
Special welding rods, then machining.
Or machine down, shrink fit a longer piece to remove problem permanently.
Labor to remove, repair and fit back would be expensive.

Ship had a twisted crank, was trued to 0.007" and machined, fitted back.
40' long, 8' crank throw. Daihatsu engine, IIRC.

You tried to fined the real original long crank? That would have solved the problem for good.
 
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This has been sitting behind a friend's house since 05, regular inquiry led to her asking me if I wanted it for 1000$. I'm on the way over... It's pretty crusty, but that's to be expected. 1984 bmw r80 g/s.


PXL_20230222_000555678.jpg
 
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Good score……those ohlins shocks are worth that! (Edit…..only one shock…..looks to be a GS80 with the one sided swingarm!)
80’s early 90’s? (Edit II; sorry didn’t see the supplied info….84 R80GS)

they made a dakar version of it that would be sweet to restore to. 😎
 

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This has been sitting behind a friend's house since 05, regular inquiry led to her asking me if I wanted it for 1000$. I'm on the way over... It's pretty crusty, but that's to be expected. 1984 bmw r80 g/s.


Ever since a trip down to the bay area in 2006 or so, I have thought about what it would take to have a bike tucked away in a rented garage somewhere. Somewhere accessible from bart…
 
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I have the top end off, as it had a stripped exhaust spigot, but there is a beauty to working in a machine shop. I knew it was not going to be just a carb clean. I'll probably rebuild the gearbox too, without knowing who was in it last it's just piece of mind. As long as the British pound stays soft buying all my parts from motobins, and most service parts are easy to get. Hard to get is an original toolbox and toolkit. There should be a special place down below for people who don't keep the original stuff with the bike.
 
I still have a couple of those from my high school mechanical drawing class. Man, I loved that class. Too bad it's a dying art.

These days whenever I need to sketch out a block diagram or schematic, I always intend to force myself to climb the learning curve and get up to speed on some kind of CAD software. Then I end up scribbling on the back of an envelope as usual. ¯\(ツ)