How do I tell the size of my maxim engine?

Okay guys I know I have seen this somewhere and explained, but I can't find it anywhere. I have a 1983 750 or atleast I was told it is a 750. It looks suspiciously like the 650 I have though too. I tried my go to technique of typing in the casing vin on google, but no luck. What are your tricks?

Oh I guess the process of being able to tell the frame would help too since engines can be swapped out. Vin is pretty beat up on the neck tag though.

Sorry again for I'm sure the repeat question.

 

The size of the engine should be stamped on the front of the engine between the 2nd and 3rd exhaust pipes. I have an 82 750 maxim, with 748 cm stamped on the front.

My 82 has the square gauges and square headlight, but I believe in 83 they went back to round guages and a round headlight like the 650's.

 

The "shorty" VIN, which consists of the model series and serial number portions of the full VIN, is all you need.

That number is cast onto the top of your transmission housing.

With that, and the info here: http://xjbikes.com/Forums/viewtopic/t=14577.html you can easily determine what you have.

 

The dead giveaways between the 750 and 650 Maxim (chassis) are - (the 750 has-)
Adjustable driver's pegs, dual front brakes, alloy handlebars (except '83), and a more complex rear grab rail. One gallon bigger tank would be less obvious. Alloy side covers (might be missing).

 

Sweet. Thanks guys. Both ways worked. I bookmarked that page so I don't lose it this time. I will use it to reference my other bikes too.