I have what I think is a 72 dt2, but I could be way off.
I did double check the vin decoder, which confirms.
But, I keep getting wrong parts.
Recently a magneto, and my gasket kit looks off, crank seals are too small.
Can someone confirm.

Serial dt1f 118570

I've gotten parts for this engine, once upon a time, and had a few issues so I wrote a few notes on the registration, and thought I had learned a few things.

That VIN code ties in with a 1972 DT2.

Random questions/observations:-

1) I'm not convinced that those characters punched on to the engine are in Yamaha font - others can confirm either way.
2) Does the frame have the same number?
3) Would you be able to post some more photos of the engine, from different angles and standing further back?
4) Ditto the bike in general.

Maybe someone has got hold of some un-numbered crankcases off a different model and then stamped them to match the frame?

Thanks for the reply.
The bikes in various tubs right now, but the frame numbers match those given.
Ill try to find a complete picture in my photobucket.
The crusty old number is hard to read on the frame tag, but it is also dt1f 118570.
I know the engine has been matched to the frame for at least 30 years, but I guess someone could have ground it down and restamped it, 32 years ago. Or 40, lol.

Here a pic without the pb banner, took a couple tries to get it to post right side up,
Sorry, I'm new.

Unfortunately your "wrong parts" problem is likely sellers not knowing what they are doing.

Sometimes a clue is to look carefully at the fitment they list... if they say a piston they have for sale fits both a 250 and 360, obviously that can't be right as the bores are considerably different sizes.

I've seen gasket sets listed to fit many years and engine sizes which is also improbable unless the set has several different versions of the different gaskets included.

That does make sense, thank you for the input.
The seller stated they would work for a 69-74 dt250, but from what i can gather, from just poking around not knowing what to look for..
I think 72-73 are kinda their own thing.
Once I can figure out what these gaskets I have are for, ill try to pass them on to someone who can use them.

Thanks again.

68 to 73 are "similar"... big difference is reed valve in 72-73. But you're right, 72-73 is what you really need.

1974? That was a complete engine redesign. So it's likely that's what you got.

If you post pictures of gaskets you have, one of the experts here can probably ID what they fit.

Also, someone might have a recommendation for a set to fit your bike or feel free to post a link to a set you are considering buying and other members can often help tell you if they look right for your bike.

That looks to me like a 1973 RT3 (ie the 360 version of the DT2/3) petrol/gas tank. Non original front mudguard and maybe rear painted to match?

Is there an engine capacity cast into the base of the barrel/cylinder/jug, or is there a decompression valve just above the exhaust outlet? What does the tacho red line at? 6.5k = RT2/3 and 7.5k = DT2/3. The original tacho wouldn't have had a neutral light within it.

It's obviously something of a bitsa (nothing wrong with that!), so it's therefore preferable to id what bits are off what bike before ordering replacement parts.

Once you've identified the wheel/brake hubs (there will be numbers cast into them that will assist with this), make sure that you replace both sets of brake shoes.

The tank IS off a dt360, and bars. I crushed the original. The wheels I didn't change, but should be.
The fenders I don't recall, I can't exactly remember replacing. for sure didn't paint them though.
It was never a "paint it" type of bike.
I obviously can't be 100%, but just looking into the dt2 engines a little today, this is the correct sort and the numbers match. So ill just go with that for now.
I did find 2 different places where people have questioned the font of the engine serial, and suggested it must be a dealer replacement engine, or scrubbed and restamped case.
Honestly, I'm more apt to believe there are a few that are just stamped a bit weird.

It lived a hard life before I got it. So easily could be any number of changes. And then I rode it to school and back through very ruff steep terrain. About 2 miles each way.
The 360 was to replace the 250, as I felt I outgrew it, but it didn't last as long as i had hoped.
And with my lack of knowledge I could not set the 360 up to excel in that scenario.
The 250 was better suited for it.
Although the 250 would freeze often when I was pushing it, it would always cool down and come back.

Eventually I let it sit, it rusted out, and I got the urge to see if I could ride it, and broke the right swing arm mount, and made some bad choices with it from there. Then crashed it pretty hard.

But you know how it is probably, I was digging for something else in the shed, started pulling out dt parts, and having memories.
Forgot what I went to the shed for, but I've been cleaning and sorting dt parts for a few days now. Haha

I didn't realise that you'd had it so long - I assumed (incorrectly, again, Al! ) that you'd only just got it.

This is going to make me sound like a right old pedantic arse (sorry, ass! ), but those 72 and 73 250s were DT2 and DT3, likewise the 360s were RT2 and RT3 - the DT250 and DT360 weren't introduced until 1974 and, as Mark said, were redesigned bikes. Some parts are compatible between the DTs and earlier bikes, but not that many.