I bought this flywheel on e-bay. From reading other post on this site and looking at information on Rex's Speed Shop, I'm beginning to suspect that it isn't for my DT360. This wouldn't be the first time for me getting the wrong parts on e-bay. Thanks for your help.

The notches in the crank snout look right.

My original flywheel was corroded beyond use but this e-bay flywheel appeared to be a match.
This is the information from Rex's Speed Shop about fitment for a DT360 that caused me concern.

Requires the flywheel to be stamped “FOTO2173”.
Fits:
DT360A 1974
DT400 B&C 1975-76MX400B 1975
IT400C 1976
YZ400C 1976

Panic ye not!

I have a brand new DT360A flywheel yet to be fitted. I have just had a quick look and it is stamped FOTO2171, the same as yours.

The Partzilla website shows that the flywheel for the DT360A is not shared with any other models.

I would never be so presumptuous as to say that Rex's are wrong, but I don't know what the differences between the DT360 and DT400 flywheels are and whether or not Rex's new fitments negate these differences.

Thanks. I’ll send an e-mail to Rex’s to see why he has the other flywheel listed for the DT360A.

If still needed I have a NOS one that I don't need as I converted to points. PM me if you want it.
Trig

Here is a picture of the side of the flywheel for the DT360. As you can see it is machined back. This is for clearance in the case where it would rub a boss if not machined. I found this out when fitting a flywheel from a later DT250 for a points conversion. I had to machine it so it would not rub.
Trig

From what I have been learning from both Rex as well as other sources, the flywheels used on the DT360A, and the DT400B, C and MX can generally be interchanged between those bikes, however may have some differences that make the aftermarket CDI setups stumble a bit. I cannot tell you for sure, so worst case scenario, would be to send your flywheel to REX (kind of spendy I know) and have him verify it will work with his setup.

Dealing with this right now myself. I have an original dt360 flywheel that is FOTO2171, checked it after I saw the info in the rex's ignition system product info page that it needed to be a foto2173.