750 engine in a 550 frame (pics)

[LeeGS550E]

Here's a few pics of my latest re-take on the 550. Second gear was chipped in the 550 engine, and a 700 engine came up for sale locally with only 7000 miles on the clock, so I figured it was fate.

I need to give a big thanks to Kevin (Distraction628, who helped both with motivation and motorcycle wisdom.



Here she is with the little sister ('81 GN400X).



I still need to finish the seat, of course. I made the new pan yesterday after reviewing some helpful GSResources threads about how to do that. I am hoping to find some nice stiff auto foam, unlike the soft stuff I used before from JoAnn's Fabrics.

Comments welcome. I am reading your thoughts, though..."Why didn't he just buy a 700?" Because that would have been too easy.

Cheers,
Lee

[80GS1000]

Nice work. And because a 750 in 550 frame is faster than the 550 and probably handles better than the 750.

[distraction628]

I LIKE IT.......Now bring me the Z and let me goto town on that motor....HEHEHE......

[LeeGS550E]

While you do the motor, I'll put some floor boards back in it :shock:.

[LeeGS550E]

Nice work. And because a 750 in 550 frame is faster than the 550 and probably handles better than the 750.

I knew if anyone would understand, it would be you!

[t3rmin]

You're gonna love that motor! Great work!

[skreemer]

What issues did you have in mounting the motor in there? What year is the 700 motor?

I have a somewhat complete 85 550ES in the basement I've been using for parts and been trying to think of what I can do with it...

[LeeGS550E]

What issues did you have in mounting the motor in there? What year is the 700 motor?

I have a somewhat complete 85 550ES in the basement I've been using for parts and been trying to think of what I can do with it...

The engine is an '85...only year of the 700. Basically the same as the gsx 750 engines.

First problem was the engine being too tall for the frame:



Solved by removing the smaller top tubes, and coping out a section of the big top tube:



Replaced with heavier duty 1" tubes, and a plate where I cut the big tube:



I'll continue pics on the next post...

[LeeGS550E]

More pics:



Had to install a flat plate to replace the tube steel that tied the down tubes together. The 700 engine has a lip at the front of the head that was bumping the original bulkhead:



Also had to do a new bottom crossbar and new motor mounts all around. Alignment was not hard to do though:

[t3rmin]

Wow. Now I'm even more impressed. Very nice!

[brveagle]

Someone's got some welding skills...