Shaft peened need to retap

Will'smotobikes19

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The magneto side of a crank got damaged from light taps of a hammer-figures. What is the thread for the shaft? Is it M8 x 1.0? I tried using an M8 x 1.25 and it made it worse. It’s the neighbors crank that’s already mad at me about bearings. What type of metal are the cranks anyways? Whatever it is is soft metal like a low carbon steel.
 
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JerboaJohn

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reasonably sure the cranks are A36 steel. it's like a medium hardness but not super hard
 

JerboaJohn

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if the threads are gumballed already, you can't hurt by going up a size like to 11/32, 3/8 or 10mm
 

Will'smotobikes19

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The case halves wouldn't come apart please don't be too hard on me. I put painters tape on the hammer and it still messed it up. The stupid engine had nothing wrong with it except an improper and restrictive intake gasket and probably poor tuning. It was my neighbors engine and he says its a parts engine now. He said they "drilled the holes for the magneto wrong" and that's why he thought it wasn't running right. He's the same guy that's been arguing about taking the seals off the bearings.
 
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Jag

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Just go on eBay and but another engine for $70 or buy a new crank.
 

Will'smotobikes19

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At this point I don’t want to buy him anything else I already bought him Japanese bearings (which he’s probably going to waste) and a gasket kit. I guess I’ll just delete the thread if no one knows what size the rotor side threads are.
 

Jag

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How are you going to fix it if they are already striped? I’ll get you the size of the threads in a few hours
 
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