Big ol thumper

   #1  

wormser77

BAMF
Joined
Jan 2, 2002
Messages
9,228
Location
spokane wa
Coming home with me. The jug on this thing is massive!
Been sitting in one of my regulars at the bar shop for 30+ years, his father was a hill climber and it came out his shop.
Kinda strange set up with dual compression releases.
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   #3  

BilletMan

Makes Chips and Rapid Conversaion
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Dec 29, 2001
Messages
18,980
Do you plan on making it run? If so, split it apart....if there is ANY hint of rust in the big end bearing of the rod, you're wasting time, effort, money if you don't have the crank rebuilt....parts may not be available...just say'in....
 
   #7  

maui

Big Bore diggidy mayhem
Joined
Dec 12, 2001
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27,521
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see above
Do you plan on making it run? If so, split it apart....if there is ANY hint of rust in the big end bearing of the rod, you're wasting time, effort, money if you don't have the crank rebuilt....parts may not be available...just say'in....
I’m pretty sure you have a crankshaft for that next to your lathe....It looks like a giant billet chunk of 4130
 
   #9  

BilletMan

Makes Chips and Rapid Conversaion
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Dec 29, 2001
Messages
18,980
I've done billet connecting rods out of 8620, had them copper plated, removed plating from bearing areas, had them case-hardened through the carburizing process, conducted final grinding/honing processes....it's more than just a little expensive for prototype stuff! Ever wonder why connecting rods are copper plated?? The plating is a masking layer for the carbon-rich carburizing process...the carbon doesn't go through the copper....you want the bearing areas to case harden properly (they take on carbon) while other areas remain "tough" (yes, it is a metalurgical term) and ductile, not brittle......so there, that's your lesson for today....I'll bet MC hadn't a clue...
 
   #10  

BilletMan

Makes Chips and Rapid Conversaion
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Dec 29, 2001
Messages
18,980
Where's hagrid? He's the king of this stuff!
 
   #12  
OP
OP
wormser77

wormser77

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Jan 2, 2002
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spokane wa
So it's a big ol kackler👍🏿
I'm just gonna pull the plug, put a little 2 stoke oil in it overnight and try and turn it over.
If it does shift it through the gears and sell it. The vintage mx race scene is pretty big around here.
I believe it's an early 70's 400.
 
   #13  

pimpslayer

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Oct 31, 2002
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On the buckle of the Bible Belt.
/--------/
I believe it's an early 70's 400.
Looks too big to be a 400....looks more like a 501.

Ankle spraining, arch flattening bastards !!

I limped for 2 months back in '93 from trying to kickstart an early '80s 400 Maico without a good boot on my right foot. Timing was a little off, and it killed my arch.
.
 
   #18  

hagrid

Human sized Loofah Pouf
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Apr 28, 2013
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Pittsburgh
He's busy tooling around on his little shovel, likely burying some migrant male sex worker he just met off grindr in the backyard of his local church.
Ah... I see the local green-eyed monster has arrived.
 
   #19  
Joined
Jul 8, 1999
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1,863
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OMEGA
Was my dream bike as a kid, I was still racing YZ80's at the time but remember the Maico just destroying the berms it had so much power.
 
   #24  
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OP
wormser77

wormser77

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Joined
Jan 2, 2002
Messages
9,228
Location
spokane wa
So this motor appears to be stuck, just oiled it to see if it will bust loose.

Anyone have an idea on what to ask for this beast?
 
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