SHIMANO FC-M640 Zee 10 Speed Crankset

I installed the Shimano FC-M640 Zee 10 Speed Crankset at the end of February 2020. I’ve ridden my MTB almost every day. The crank arms are 175 mm. The sprocket is 36T, 104mm BCD single speed ring designed for 10 speed drivetrains. The box included a BSA 68/73mm bottom bracket.Initially, I installed the crankset w/the original Shimano 8-speed 11-32T cassette. I rode it like this issue free for a week before I swapped out the chainring for a Fifty-Fifty 104BCD 36T NW Oval chainring. This, I rode issue free for a week as well. I then upgraded to a SunRace MS3 10-speed 11-42T cassette, Shimano Ultegra CN-6701 10-speed Chain, Shimano Deore XT RD-M786 SGS Shadow Plus rear derailleur & have now ridden it almost daily, issue free.The installation was simple. I upgraded from a Shimano square tapered bottom bracket to this Hollowtech II. Removing the old bottom bracket & cleaning in prep for the new bottom bracket was the hardest part of the installation. The improvement was amazing. I knew it would be better, but was surprised how much better.The set did include spacers, but I ordered a couple extra spacers (Shimano FC-M760 Hollowtech II Bottom Bracket Spacers, $6). These can ware & break. I think it’s a good idea to keep a couple extras on hand so if one does break, I won’t miss a ride waiting for the part.For me, this was a solid upgrade, a great crankset, Shimano quality cranks & bottom bracket at a great price (sub $120). If you’re looking for a new economical great performing crankset, the Shimano FC-M640 Zee 10 Speed Crankset may be a great choice.Thank you for taking the time to read my review, I hope you found it helpful.

I use these cranks for bike polo and singlespeed MTB, they rock! Nice wide q-factor, but make sure you know your bottom bracket shell width before you buy these!!! They come in two spindle lengths so if you’re getting these for a 73mm BB shell you want to get the 83mm spindle. Same price as the standard. Comes with bearing cups and spacers.

These fit on a Big Ripper. I was worries at first because I had to use all 3 of the included spacers but it fits great and there are no unusual noises coming from the cranks. They are light, stiff, easy to install, and look great, I purchased them again and put on a different bike and about to grab another set for another bike. I personally love them.

As part of a rigid MTB drive train upgrade, this Zee crank's proving to be a worthwhile investment for me. Going from 3x to now a 1x setup, running a 36t chainring along with a 12-28 cassette, the crank's providing a very smooth and solid feel both on road which is where I do most of my training and on the occasional off road excursion's, it's equally competent.

This is for 68-73mm BB, but there is also a Shimano ZEE FC-M645 which is for 83mm BB. This looks exactly the same as the FC-M645 and only differs by one number. If you're using a DH bike, you probably need the 83mm M645 model and not this one. Super confusing and frustrating. Shimano should make the designs different on the cranks so you can easily tell them apart.

This fit my bike perfectly and I was able to convert my old Shimano Derore 3x to a 1x. This came with spacers for crank and spacers for pedals and new bottom bracket. I didn’t need the BB or any of the spacers but saved for future replacement. Overall this is a well made and good looking crankset. Highly recommend.

The Zee crankset is fantastic especially for the price, complete with a bottom bracket it goes together fairly easy. There is a special tool needed for the crank arm plastic nut, but I just hand tightened. Be aware the instructions are useless, you will have to dig around on the Shimano website to figure out all the small settings like BB width. I ended up switching the chairing to a smaller size right away as there was no 32 tooth option. Since installation I have had no issues, no creaking and no adjustments needed.

Brought a 09 Norco Six One up to date by installing this along with a SunRace 11x46T cassette on the rear. Could not be happier with the overall change and upgrade. Zee have near all of the current race improvements of the Saint line at an affordable price. They lack nothing in durability IMO.