GT750 vs GSX-R1100...

[pjmcburney]

I have it in the back of my mind to fit one of my spare GT engines up to my '92 GSX-R11.


I reckon it would be fairly straightforward except for exhausts (custom chambers would have to be made) and fairings - I'd like to keep it looking much like a GSX-R.

Now I realise the GT engine is wider than the GSX-R engine, so to that end, what might my options be to slim it down?
I wonder would it be possible to mount the external GSX-R alternator onto the GT engine in a similar way?

Any thoughts from the collective?

[tz375]

Well that's one way to tame the power of GSXR11...

You can drastically slim the points side if you change to an electronic trigger and slimmed down cover. On the Alternator side, I like the look of a GSXR alternator which is a couple of inches less bulky but needs a new side cover to make it work.

The shafts are 1-2mm different diameter, so something has to change either weld and grind the shaft or make a thin wall adapter.

[garry55]

I am looking at how I could fit an external alternator (like the RF900) in the space vacated by the starter motor, then belt-driving it off the water pump shaft?
Just a thought.....................

[pjmcburney]

Well that's one way to tame the power of GSXR11...

You can drastically slim the points side if you change to an electronic trigger and slimmed down cover. On the Alternator side, I like the look of a GSXR alternator which is a couple of inches less bulky but needs a new side cover to make it work.

The shafts are 1-2mm different diameter, so something has to change either weld and grind the shaft or make a thin wall adapter.

Ha, yes the power output will drop some .


It's just a bit of an idea at the moment.
The Gixxer rolling chassis is a perfect weight and size for a GT engine, and I'd be creating an interesting hybrid that theoretically could do serious miles and work quite well.

I think .

As for the alternator, I wonder if I could mount it in a similar position as on the GSX-R engine and run it with a small pulley and belt from the end of the crankshaft where the original alternator was?
I'm sure I've seen something like this on another bike somewhere...

[Suzsmokeyallan]

Hows the length of the GSX-R frame from swingarm pivot to the rear of the front fender. When I was thinking of this same idea for a Bandit frame I had, I would have had to move the swingarm pivot back a lot to get the engine in for the headers to clear the fender. So I scrapped that idea and decided to build that Bandit up into a bike out of parts from Ebay.

[tz375]

Paul, you are correct. There was a guy in Europe that created a 1000cc GT with powervalves and more welding and machining than a ship. He had a belt driven alternator and I want to say that it was under the motor and he fitted the radiator under the seat.

Check out a more modern K series alternator. They are about 60mm thick or so and will almost fit inside the crankcases with only about 30-40mm sticking out. You could probably mount a trigger outside of that and flat plate the left side and fit an electronic water pump from Davis Craig and electronic tacho and dump all that weight on the left side.

With all that empty space above the back of the motor to fill, how about EFI and Reeds with secondary injectors in the reed boxes? Just sayin'..

[Suzukidave]

Looks like a belt but i wonder if its not gear drive off the clutch

[tz375]

He used a gear drive off the clutch.

[Suzukidave]

Any more thought on your project idea ?

[pjmcburney]

Um, not yet .


Dave, being well-versed in this sort of project, have you measured the width of the GT engine compared to the GSX-R?
I know it has to be wider, but I wonder how much?

If I ever go ahead with this, it has to be an absolute sleeper, so getting the GT donk to fit behind the GSX-R fairing is a must.

[Suzukidave]

If you are asking about the width of the '92 GSXR 1100 engine vs the GT750 , i dont have a water cooled GSXR handy but the oil cooled GSXR 1100 engine is @19" across the side covers . With my yellow custom with the 92 GSXR fairings the GT side covers poked out the sides

[Suzukidave]

As you know its the length of the GT engine front to back thats the big problem as the GT engine is a couple of inches longer

[Cragdog]

Dave you have 2 custom GT750's in modern chassis?!?!
Way too cool

[Suzukidave]

LOL .. no .. the yellow bike is a bitsa with a modded GT750 frame .

[Cragdog]

LOL .. no .. the yellow bike is a bitsa with a modded GT750 frame .

Ahh.. I see, what is a bitsa? Please enlighten me! Looks siick tho.