83 GS750E/ GSXR engine swap

[smarzinski]

Just wanted to start this and post some pics if anyone was interested. Engines a 91 GSXR750. Waiting on carbs, filter pods, 520 chain conversion, and a new starter. Enjoy.....or hate it!

[Flyboy]

Hey, come on now, whats with that?
You can't post something like that and not give us all the gory details.
Walk us through the conversion, looks like a super nice project, will be watching with interest.

[smarzinski]

Well, I thought the starter was bad, turns out it just didnt have a good ground. I did a bunch of snooping online to find some info on how to wire this pig, found a good link on gixxer.com forums. Someone luckily did a 91 engine into a 87 gsxr frame and had to rewire like I did so I got to see pictures and match wires with my wiring diagram. Im using the stock wiring harness from the GS. Basically Im working on getting the cdi hooked up so I have spark, and then I need to figure out how to wire in the alternator. Also have to do a 520 conversion as my chain rubs on the rearset mount. Whats I have to do yet is:

Fab some front engine mount brackets
Get my carbs and clean them up (Mikuni BST36's)
Do the chain/sprocket conversion
Finish fabbing the Oil cooler mounts
Finish up the wiring
plug and oil change

That should about do it, other then polishing the exhaust but thats not something I need to do right now. Im ready to get this thing on the road!!! I have my old engine listed in the parts forum if anyones interested, comes with the carbs and the clutch only has 600 miles on it. Not gonna give it away but not gonna ask an arm and a leg either. Thats all for today, more later.....

[smarzinski]

Rear mounts lined up on both engines, just needed to make some bushings to fit in the gsxr rear mounts because the gs bolt was a little smaller. Moved everything out of the garage and cleaned up since i shouldnt be spilling anymore oil on the floor! After everything dries I will be going to measure up the front mounting points. They arent to far off so I will be going to by some aluminum and copying the gsxr mount and moving the engine mounting holes in a little to line up with the engine. Everything is lining up pretty good so far. Taking some rough measurments without the front brackets (with engine braced in place temporarily) it is centered. Now of course I have to play the waiting game and order my 520 conversion. Going to be buying a 89 gsxr rear swinger this fall and putting it in, just for a little more strength.

[Flyboy]

You say it is a 750E, I assume it is an EF or ES?
Is the Gixxer electrics from the stator and the ignition pick ups really that much different from the GS?

[smarzinski]

its an E (ED) the ES had a larger, stationary front fairing. Basically the same bikes though. The GSXR engine runs an alternator instead of a stator so the wirings different. Also, the cdi needs to be wired different. The plugs are the same but the wires arent. Trying to find out how to test for spark from the cdi so I know which plug fires which cylinder. Plus, I ride the short bus when it comes to wiring... The gsxr has 2 wires coming for the signal generator and the old gs has 4. I have pics in my profile of what it looked like stock, other then the paint that is.

[Flyboy]

I ride the short bus when it comes to wiring.

You and me both.

[Busafied]

I installed a complete wiring harness off a late model GSXR 1993 to be exact.
\ didn't want to deal with the wiring on my 83 GS750/1127 conversion AKA FrankenBike.

Ron

[smarzinski]

Well, I think I have the wiring all figured out, I at least have spark. Worked on the front engine mounts and oil cooler mount today. Got the oil cooler mount half done. Since I am running 36mm carbs instead of the 38's I have to get different intakes so I am going to be doing some shopping around for awhile. Planning on having this thing on the road in 3 weeks though.

[kingofvenus]

Hey, come on now, whats with that?
You can't post something like that and not give us all the gory details.
Walk us through the conversion, looks like a super nice project, will be watching with interest.

I'll do it this winter when i'm doing mine. I have to freshen it up first, mine is an '89 short stroke version, that later on down the road will get a 1052 injection...

[smarzinski]

Gotta take a break for awhile. Need to find some parts. Using Mikuni BST36SS's and the bike came with 38's on it.....

[smarzinski]

Engine is in and I got it fired up. Needs a jet kit and filters desperatly! Camera wasnt working so I dont have any pictures from the build. I am willing to asnswer any questions anyone has though. I ended up using the stock gs wiring harness on the bike. Everything works fine. Got 14 volts at the battery at idle. Have to take the tank to a local body shop to have some modification done to it and my petcock sits on top of the No.1 carb. Sorry I didnt post pictures........but here it is with the engine in it.

[Curly]

Is that oil cooler not mounted higher and closer to the frame because you're using the stock gsxr lines?

Closeups of the rear, lower, and front engine mounts would be helpful. Along with clearance pictures from the valve cover to the frame, and the sprocket area, like what kind of room we have for rear sets, etc.

[smarzinski]

Ok, what clearance for the valve cover? Are you talking from the top of the frame or the front? As far as the rear engine mounts go, i used the stock brackets. I fabbed some front ones and bent them a little bit to line up as the engine mounts are slightly outward of the stock frame mounts. The bottom (side) mounts arent on yet. I have to make some. Im not to sure what to do for the left side mount yet either because I cut of the bracket on that side because it was welded on and hit the new engine. As for the oil cooler, yes for now I am using the stock gsxr lines. I plan to get a Mocal oil cooler and make my own lines. I ended up getting a 520 conversion and am running a non o-ring chain so everything clears. Its tight but it does clear. I will work on getting some pictures for ya though.

[needragr]

GS ED mods

Engine is in and I got it fired up. Needs a jet kit and filters desperatly! Camera wasnt working so I dont have any pictures from the build. I am willing to asnswer any questions anyone has though. I ended up using the stock gs wiring harness on the bike. Everything works fine. Got 14 volts at the battery at idle. Have to take the tank to a local body shop to have some modification done to it and my petcock sits on top of the No.1 carb. Sorry I didnt post pictures........but here it is with the engine in it.

What about the wheel/fork conversion ?
From what bike(s) ?
Clearance issues?
Tire sizes?