DT400 question

[jvollmer]

I have a 1976 DT400 with a trashed engine. I have a 1977 DT400 Engine.
I want to swap engines so I can ride and rebuild the bad engine over next winter.

Yamaha changed a bunch of stuff on these engines starting with 1977. THe exhaust is on the oppisite side which makes the fins on the head different. Other changes are to the clutch and cable routings/hookups. All this is stuff I can deal with.

Does anyone know if the engine mount spacing, electrical, front sprocket spacing, or anything else was changed which prohibits this being a bolt in swap? It would be great if I am able to do a engine swap and go ride.

Thanks in advance

[urbantiger]

Originally Posted by jvollmer

I have a 1976 DT400 with a trashed engine. I have a 1977 DT400 Engine.
I want to swap engines so I can ride and rebuild the bad engine over next winter.

Yamaha changed a bunch of stuff on these engines starting with 1977. THe exhaust is on the oppisite side which makes the fins on the head different. Other changes are to the clutch and cable routings/hookups. All this is stuff I can deal with.

Does anyone know if the engine mount spacing, electrical, front sprocket spacing, or anything else was changed which prohibits this being a bolt in swap? It would be great if I am able to do a engine swap and go ride.

Thanks in advance

HI...
a few years ago i remember a mate blew up his dt400b twinshock and fitted a dt400 engine from a 78 monoshock model and as far as i can remember apart from some of the mods you mention it fitted ok...i myself own a restored 1981 dt250..
sean

[jvollmer]

Thanks,
That is exactly what I was looking for.

[autowrench]

I understand the 77 also had different porting. The reed block is different. I have the opposite setup. I bought a 77 that has a 76 cylinder and intake. The airbox to carb boot won't fit up. They changed to monoshock in 77. Different airbox. Also 4 petal reeds instead of 3. Let me know if you make the airbox thing work. I'm thinking of trying the 76 boot and trim to fit. The carb slide cutaway and needle jet are different too, BTW.
Tom