Do I really need 5th gear? GS 650-550 trans swap

[Ricey650]

Hi all you gs wizards out there, what's your take on this...

I currently have the crankcase of my gs650e split and am rebuilding from ground up.
While disassembling I noticed a few teeth on the gears looked a little average.
After a bit of research it looks like the gs550 and 650(e only) share almost identical bottom ends.
If this is the case, I'm thinking maybe a should bolt in a 5 speed trans from a 550 rather than reinstall or replace the existing 4 speed 650 trans.
The 550 trans are so much easier to come by, and I get an extra gear - win, win right?

Has anyone had experience with this? Am I right in assuming the 550 trans will just bolt in?
Aside from the shifter drum, is there anything else I need to change to complete the conversion?
And.... is it actually worth doing?!

Look forward to you feedback.
Cheers!

[Guest]

What kind of 650 do you have that only has four gears?

And what 550 are you looking at that only has five gears?

And what's wrong with teeth that look "average"?

[Ricey650]

What kind of 650 do you have that only has four gears?

And what 550 are you looking at that only has five gears?

And what's wrong with teeth that look "average"?

Apologies, GS650e 5-speed converting to GS550 (any) 6-speed
I short changed myself a gear 😆

[tkent02]

Don't know if it would all fit, but if it does that would be good to know. Worth doing? The 6th gear and the closer ratios is one thing I really prefer about the 550s.
Shift forks would have to be different to match the drum. Have no idea if it would work, never seen a 650E taken apart. Are the shafts the same length? Diameter? Are they in the same positions relative to each other? Are the cases the same exact width? The neutral stopper in the same location? Does the shifter use the same linkage? No big deal there, but you might have to learn to shift backwards.
Suzuki likes to do things the same across different models so it could fit, on the other hand the 650 is a bit of queer duck, a lot of it is done differently than the other GSes.
Take a few pics along the way, if it works do a nice write up of the project.
And if it doesn't work post that too, you may save someone else a lot of wasted time and effort.