82 750 seca to 82 750 Maxim

So through the process of elimination and bad luck i have determined that my 82 750 Maxim has the dreaded starter clutch issue bike has 40k miles and runs great and looks just as good to. I found an 82 750 seca which only has 13k miles,4/1 header no front braking system and no title for 300 bucks I guess we can see where this is going.The body on the Seca is in good shape but has visible rust in the tank so i could part the Seca out and swap the motor into my maxim with the header .I have searched posts and some say the motor bolts right in some say it won't Help me plz! 8O

 

pretty sure they both use same engine.

 

Yep, same engine.

 

It's not EXACTLY the same engine- - the cams have different profiles, the gearing is 8% different (estimate) and there was an issue with the shifter.
I don't remember exactly, but somebody ended up with a reverse shift pattern, which is cool anyway !

The motor will bolt right in, and even the "brains" will work. And the carbs.
Combining a Seca and Maxim is Sexism !!

 

I just checked for 1982 SECA's and Maxims. Both show 4K0-12171-00-00 for the intake cam, and 4K0-12181-00-00 for the exhaust cam.

For the 650's there are differences between Maxim and SECA cams, but not for the 750's.

FWIW, the middle gear set is also the same between SECA and Maxim 750's.

 

I know one of the old posts I had looked at showed adifference in I beleive it was rear motor mount bolt like one had a single long bolt and the other had2 smaller bolts an important consideration since i don't wanna hack frames just need it to be plug and play also carbs may be different brands with the Seca having the better ones.

 

The crank and clutch basket gearing is where the difference is made up.
The difference in the rear rim size.
I didn't know the cams were the same.
The big issue is still the shifter, in my opinion.
If you can work these things out, then go for it !!

 

why not just fix the maxim ? all 13K means is thats when the speedo stopped
opening up the cases and changing the starter clutch ain't rocket science
just a few tools and taking your time (and a book)
can you check the compression on the seca? does it pop out of second gear?
if you can get the seca for 200 go for it, just for parts, it's nice to have a valve cover or something that you can work on at your leisure then just pop it on

 

I was kinda thinkin the same always nice to have the extra stuff laying around

 

Does the 750 Seca have rearsets? That would be the reason for the reversed shift pattern.

 

Don't know what you mean by "rearsets", but here you can see what a 750 SECA shifter looks like:



It's got an extra linkage and an idler to move the shifter relatively forward from the shifter shaft in the gearbox, but up on the shifter is still up (CCW) on the shifter shaft.

 

Yup- those are rearsets. Same as on my 650. The Maxim doesn't have them. Since the shifter faces the rear, instead of the front, lifting the shift lever will make the shaft indeed turn counter clockwise. However, on most motorcycles, (Maxim included) the shift lever is mounted directly on the shaft, facing forward. On these, lifting the lever will rotate the shaft clockwise. That is why the shift quadrant on the Seca is different than on the Maxim.

 

Hmm, I stand corrected. Went looking for a 750 Maxim pic to be sure, and it looks like there still is a linkage, but the shifter faces forward. Can't make out if the linkage crosses from top to bottom, though.

 

Hmmm... I'm not sure about the 750's but I recently put a 650 Maxim engine in my 650 Seca. There were a few issues, one of which being the shifter arrangement. I'm not sure about this idea that the shifting will somehow be reversed. I took the shifting coupling from my old Seca engine - and this has to include the faceplate due to the protruding linkages - and everything works just like it used to. While the Maxim and Seca were quite different inside the shifter compartment with extra pins and things is different positions, there was place for everything and it was quite self-explanatory once I saw it. You'll need a new shifter faceplate gasket for sure.

So I had no problems switching the shifter mechanism over and didn't end up with any strange, reverse order. Again, this was a 650 - I can't vouch for the 750.