Help identify my bike

I recently bought an older 250 Yamaha bike, pretty old but in pretty good shape. Runs good, just need to replace tires before long. I understood it was a 72 or a 73 model but I am trying to be sure and see if the engine is same as frame as far as accuracy. the frame has RT1-186654 on it and engine has DT1F-35654. I see references to both RT1 and DT1 bikes so I am doubtful of the engine being original. Any help as far as year or either or both as well as confirmation of typed appreciated!

I had both of them. The DT1 is a 250cc enduro and The RT1 is 360cc. Engine does not sound original. The engine mounts in the frame were identical to both so they can be interchanged. Hope the info helps.

BTW - What color is it?

Thanks. Found some information on the internet that showed me the DT was a 250 only so yes, sure it it not the original motor. I am still trying to determine the exact dates they were made but that is proving difficult. Guess that is not so important but will keep looking. The bike is silver in color. As far as value goes, I would suspect that mis matching motors won't do much good for sure, and finding another probably not worth the effort. Guess it will be a fun toy to rise around for a while though.

I had both of them too.
(http://www.automotiveforums.com/vbulletin/member.php?u=279963)

I love to drive that type of bikes very much. But after seen this bike's pictures I am thinking to buy this type of bike very soon. It looks really grand and also stylish.……………………………………………………………………………….
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