New "Cafe Fighter" project with questions

Ok, I'm starting up on an '82 750 Maxim and I'm gonna turn her into a Cafe Fighter of sorts since the PO had seemingly already started the process into a Cafe Racer by the looks of it. They didn't really do that great of a startoff job so basically I'm taking the whole mixture back to formula if you will.
I have a question though about the foot controls. I've found aftermarket rearsets for the '82 750 Seca and I was wondering if the frame mounts/bolts are identical for both these bikes down in the control area. The new sets are designed to mate right up with existing mounting points on the Seca with an attachable frame to move the controls back. I'm assuming I could use this on the Maxim since both bikes are supposed to be "twin" sisters save for a few mechanical (engine/tranny?) and obvious cosmetic differences.
Can anyone (like there is a doubt based on the articles I've already read) shed some light on my ignorance? This is my first running XJ (I have another but it was in terrible shape so it's been turned into a temporary parts bike while I upgrade this one) so I am essentially ignorant of all the nuances that differentiate each year and model type.

 

the maxim has adjustable foot pegs not so with the seca, not sure if the frame under the pegs is the same, it's been awhile.The shifter linkage isn't the same

 

Adding to Mr. Polock, I wouldn't buy these parts. I have both. You want rearsets on a Maxim ??

 

Well I would like to put rearsets on the Maxim. I've noticed that the controls are adjustable and can be moved back but I would like them to be moved farther than what the current controls can go. With the plans I have for the bike; aka clubmans, redesigned seat/tail, alternate tank; I would like the controls moved to accomodate the altered riding position. But by the sounds of it if the shifter linkage is different then it is possible that the rearsets I found may not work since they are designed for the Seca. Guess I'll see how it goes with just moving the OEM pegs for now after I've finished the other alterations/upgrades.

 

Ummm... to paraphrase Norm Crosby, let me take a moment to dismell this miscontusion:

'Tain't so. The bikes are far from "twins" and were never intended as such; they have different frames and are different in a number of ways including shifter mechanism configuration, motor mounts, etc. A lot of the differences are far from cosmetic, although the motors themselves are basically the same. The frame difference is why you're finding a foot peg/bracket mismatch.

Yamaha's longstanding habit of "parts room engineering" can be frustrating at times; things that look virtually the same, or that you would assume are the same based on initial appearance, often turn out to be quite different on close comparison. Whereas things you would be sure are completely different are in fact, the same.

 

Ah. Well thank you Fitz for that moment of dismelling.
I had read somewhat on these bikes but not enough into detail about the Seca other than what similarities it has to the Maxim. Don't know where I read it or when, kinda foggy, but I remember that it had been said the Seca is the "athlete of these twin sisters." Obviously whoever wrote that was wrong, didn't elaborate enough, or just was referring to the fact they are both 750's. Either way it led me on a bit of a rabbit chase. Stupid rabbits.
I can still at least use the fuel tank from a Seca, can I not? I like the shape of tank and it'll work with my concept better than the Maxim tank. I'd really rather get another tank that can drop down onto the overly wide center frame section than have to get one created. If not, then I'll have to get creative I guess and stick to the original while I find another solution.
I do plan on getting the book from here on this bike so I have accurate material to use.

 

Possibly; it may fit but it won't line up with the sidecovers or have the same relationship to the seat at all...

You might want to try a 650 Seca tank, it doesn't have mounting ears for the sidecovers at the back or anything and will probably be nearly the same at the front, width-wise.

 

I also was under the impression that the 750 Seca and Maxim were ALMOST the same frame. I know the tanks are interchangeable, the front-ends can be interchanged (as a unit; if you work around the funky Seca remote master cylinder) and the Maxim's engine has a rubber mount where the Seca is rigid-mount. But maybe the mounting tabs/connectors for the side panels/seats/tails/etc are different. Like Polock, I knew the shifter mechanism was somewhat different (where/how the shifter control works with the transmission selector arm) but thought it might swap if you took the entire assembly.

I took a quick look at the factory manual and in the Seca supplemental section there was no additional info regarding shifting or rear braking mechanisms (with reference to the 650 Maxim). As BigFitz said, this doesn't mean that the two bikes have identical mechanisms, just similar enough to not warrant any additional service manual info.

The Haynes manual shows the different shifters on pgs 100-102 but the drawings are not to scale nor do they show comparison photos. But it does look like both the 650/750 Secas are the same, the 750 Maxim connects differently, and the 650 Maxim connects directly to the transmission selector shaft.