xtr cranks with a profile sproket on mid bb

I thought some of the ridemonkey gowers would like this a bit of mtb history on a new school bmx bike. This bike weights 18.8 pounds with brakes ti spokes and a slew of ti bolts. The profile sprocket was cut out to match the spline for the spider on the xtr cranks. The bb was a modified xtr spindal with a mid 22mm bearings with two shims for chain line. Its sweet light and stiff.

to do this convertion you need to use a mid 22mm bearing kit 19mm spindals will not fit since shimano octalink are 22 mm fist like primo and odyssey bbs

manhattanprjkt83 said:

can you provide any detail as to how the profile sprocket was 'cut' this is definitely interesting...i really great option for those of us looking for an alternative to profile crank style setups that want to maintain the micro drive config...

thanks

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the hardest part was making sure the pattern was centered. There are definately easyer ways to do this but i was bored at the bike shop and banged it out in under an hour. I started of by taking raidus measurments and centering the spline patern on the profile ring one i was sure it was center i just used som spray paint to part the spline using the old spider as a stensil. Now if you built a jig and used a milling machine or a drill press it would be faster to cut out the pattern. I just used a dremel and went slowly but it would be ideal to do it at a machine shop to avoid error. It worked great the profile ring is the same thickness as the spider sothe lock ring has full contact. Next time i do this i will go to my budies machine shop and make 3-4 rings so i have them for when i change gears or wear out sprokets.