Its time for crank updates

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speed 450mx · #201 Post by **speed 450mx** » Sun Jun 02, 2013 3:43 am

No it only had mag on the drain plug and it had very little metal or sludge during is life. The water was most through the intake not in the oil. We ran maxima and Repsol oil with most a Scott's filter and was change about every two or three races. I have another crank vixen to come out of another three year race motor and I'll send you this crank too.

wistech · #202 Post by **wistech** » Fri Dec 13, 2013 2:52 am

Got another updated crank in. This one was an atk reweld job. the cage edges are razor sharp but the rod is still good. Less than half a thousanths wear across the journal. Just a bit of sludge in the pin.

wistech · #203 Post by **wistech** » Fri Dec 13, 2013 2:56 am

Here is the weird part. Looking at the side of the clutch side crank half there are 2 burned spots with a brown stain smearing down the crank. I cleaned up the spots and sure enough its a raised area from micro cracking. Ive seen micro cracking in a lot of cranks but none quite like this. Im replacing this half for safeties sake.

speed 450mx · #204 Post by **speed 450mx** » Fri Dec 13, 2013 4:23 am

Thanks first of all. Second that crank had 2 1/2 racing seasons of xc on it so that's good that all it kinda of needs is new bearings.

wistech · #205 Post by **wistech** » Sat Dec 14, 2013 11:14 pm

I was out with Brian Kinney last night and he said he has seen this before on other brand engines. None of the cranks failed because of the cracks but he had no explanation for them.

speed 450mx · #206 Post by **speed 450mx** » Sun Dec 15, 2013 8:22 am

Oh ok at least it didn't fail. It's just weird that it did it

wistech · #207 Post by **wistech** » Sat Feb 21, 2015 2:23 pm

Wow this is the one I had always hoped to find. A cage failure right in the begging stage before showing signs . The cage has broken into many small pieces but have not fallen out or jammed up. The crank didnt have any play and spun smooth.

yamadjs08 · #208 Post by **yamadjs08** » Sat Feb 21, 2015 7:11 pm

It's amazing that it still spun smooth and freely. It wouldn't have been long, thats for sure.

wistech · #209 Post by **wistech** » Sun Feb 22, 2015 2:07 pm

There might be 2 type of failure modes. One where the cage breaks apart and jams up the rollers causing instant death. The other being the common one where the cage wears the grooves in the rod and the fatigue causes whats left of the rolling surface to spall and flake off the surface. Which would explain why some fill the frame/oil filter with metal flake for several hours while other just sieze up like this one. Of course it really doesnt matter nowadays.

wistech · #210 Post by **wistech** » Sun Feb 22, 2015 2:38 pm

Here are the part numbers for the z400 bearing.
09263-35035-0B0 original
09263-35044-0B0 newer
09263-35047-0B0 latest
it looks like they have been using different types of coating over the years on the cages . The latest ones must be using silver as the price is going way up. the last one i bought was $70.