Terryfilkins
New member
Anyone recognize this porting? I got the sled with a melted PTO side piston. Noticed the cranks been rebuilt and welded when I got the engine out. It's got numbers scribed on the case and crank parts, but no name, just wondering if anyone's seen this before?
dont know who worked on the cylinders but the numbers on the case are the factory yamaha marks, if you clean off the top half youll see the same number code, it just means the top and bottom crankcase halfs match as they are lined bored to give the correct bearing crush/squish from the factory. As for the crank also looks stock to me,as the blueing you see is from the factory heating up the crank half before they are pressed together. If you want to know if its been rebuilt it would be welded on the throws where the crank pins go thru the porckchop and if done good will also be welded on the center pins between the counterweights.
Terryfilkins
New member
This cranks been done. I have other cranks from these engines and know about the bluing from heat. This one's been welded and has numbers scribed on the throws, that's what I was trying to show in the picture but it's out of focus, I can see the weld if I look in the case with a flashlight. The cylinders look like Bender porting to me, it's got V-force3 reed, seems like it might have had the Bender stage II
if its a bender job the cylinders will be stamped example: "'BR xxx" and the x's are numbers indicating the job number.
Terryfilkins
New member
Guess these haven't been done by Bender then, I don't see any letters scribed anywhere. Guess it was an anonymous port job lol
methanolhemi
New member
I had a set of Bender ported cylinders that had the same cylinder (intake side) skirt notches you have. I had numerous other ported cylinders from other companies and no one matched the Bender design.
Possible that someone tried to copy the Bender porting?
Possible that someone tried to copy the Bender porting?
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