Bb90 to bb86
 

I am looking to swap the drive train off of my trek domane with a bb90 onto my trek Crockett with a bb86 will I have any crankset issues with this?

Have a Home Machine shop?

Nope. maybe I don't know how to ask. I want to move the ultegra 6800 from my domane 4.5 to my cyclocross bike and want to know if there will be a problem because they have different bottom bracket standards.

If it's an Ultegra crank it should work. Shimano road cranks are compatible with BB86 BBs.

I got curious and had to go do a little research on the 'net for this one! From what I can tell, the difference is that the BB 90 standard has bearings that are inside the BB shell. The BB 86 standard puts the bearings outside the shell. Otherwise, things are the same. So, it seems to me that you could put the crank and its axle from one bike into the other bike without changing anything else.

It is worth a try at least!

Thanks everyone hope you all had a Merry Christmas

Isn't there a 4 mm difference in width of the bottom bracket shell. Not sure if this would be a problem for the crank.