[Wolfe_UK]

About the timing, I'm not sure. That one is going to be a trial and error, with some help from a friend of mine who knows a bit more about it. (I asume you mean camtiming and not ignition?)
I've got two different 600cc CDI's, and an adjustable timing rotor (don't know the correct term), so I will check/adjust ignition timing with that as best as I can.

The 750cc cylinders would need the corresponding cylinder base gasket (and of course head gasket), but that fits according to my trials.
Tensioner, it seems to be more or less the same, at least the 600cc one fits okay in my 750cc cylinder.

And last, about the intake. I'm going flatslides with pod filters, mostly due to looks and sound, but I reckon you should be able to use more or less any BST CV carbs with the original airbox.

I did mean cam timing, as the cam sprockets are different. I believe the ignition timing should be the same in theory , but could be wrong?

Are we both talking about the same gasket, where the bottom of the 750 barrels meets the 600 block? Obviously from barrels up it would ideally be all 750, so using the barrel-to-head and cam cover gaskets for that engine would be perfect.

I suspect due to the increased displacement and flow with 750 head; that using stock 600 carbs and airbox would be a fail, as they'd just not be able to get enough through without changing the jetting. Given the K&N high-flow filter debates on here, too much flow doesn't suit the stock engines, with stock filter in stock airbox it should be too restrictive for the better head?
Something to think about, certainly. Though pods would be a simple fix, and just would need tuning for.

[Jimmie]

I think the cam chains might be different between the engines, and thus you'd have to use the GSXF sprockets. But that shouldn't pose a problem, since they are interchangable between the cams.

I think we're talking about the same gasket, the cylinder base gasket, as you say where the cylinders meets the block. It has to be the 750cc one, as the cylinders are bigger. Just my lack of technical english knowledge are showing. But as far as my trial fits go, it should work.

I'm not to worried about the carbs vs. head and airfilter problems in my case. As the flatslides I'm going to use doesn't rely on vacuum, pod filters are no problems. Loss of vacuum is only a problem when using CV carbs. And I've got a fair selection of mikuni jets (I'm a bit reluctant to use anything else than original Mikuni jets, even though people speak really well of for example Factory Pro). So jetting should not pose a problem, even though it will probably take some time to get it right.

But you are correct, the 600cc BST33 carbs will probably be a bit of a restriction using a 750 head and cylinders. Better then to get a set of BST36 from another oil cooled Suzuki, or perhaps a set of RS34/36, or better yet keihin fcr or Mikuni TMR. But then we're probably talking big money, compared to what the bike is worth. I decided on the VM29SS (1st gen GSXR flatslides) because I got a set for next to nothing, and I love the sound flatslides make. And of course, flatslides making the airbox problem disappear.
Also, the VM29SS can quite easily be modified to 33mm, which should provide sufficient flow, if needed.

[Wolfe_UK]

I think we're talking about the same gasket, the cylinder base gasket, as you say where the cylinders meets the block. It has to be the 750cc one, as the cylinders are bigger. Just my lack of technical english knowledge are showing. But as far as my trial fits go, it should work.

Ja, see this is what I was concerned about: The mating surfaces between the two engine sections being different sizes and there being an over/underlap as viewed with the block as a single unit that would cause problems.
But yes, you're right the bore is different so would have to use the gaskets for that sizes cylinders.

Not really a lack of technical English but also my poor explaining there methinks.. Don't even ask me to try explaining it in Danish

[Jimmie]

I wont ask no one to explain anything in danish, it would probably complicate it even further, even for me.
To be honest, danish isn't my native language either, I'm originally from Sweden.

[Wolfe_UK]

I wont ask no one to explain anything in danish, it would probably complicate it even further, even for me.
To be honest, danish isn't my native language either, I'm originally from Sweden.

[insert witty Norsk joke about Sverige here]

But yeah, based on what you've found out so far, and that there won't just be one person doing this, AND that the GSXF is currently off the road for mods/paint anyway at the moment.. Seriously considering going for this set of barrels/pistons and worrying about the cost of all the extra crap I'll need to go with them later.. The one I'm looking at has a matching head available that comes with the rubber carb boots, so that's a plus too.
Though if I do it too, you can have the credit for the idea!

[Jimmie]

Yeah, it's easy to forget about all the small things.. I'm trying to keep a list of all the odd stuff I still need to buy and figure out, it piles up.
In theory all you should need is a base gasket and head gasket, but as you've mentioned, there are lots of other small issues to work out.
I'm also changing lots of other gaskets, seals and bearings, as I'm in no hurry with the spare engine and would like not having to worry about a stupid oil seal leaking somewhere when I'm done.

So, go for it, can't go more than wrong.

And please tell a norwegian joke :bunny2 We probably have the exact same one, but with the nationalities switched.

[Wolfe_UK]

And please tell a norwegian joke :bunny2 We probably have the exact same one, but with the nationalities switched.

Oh I KNOW! I've spent enough time over there to hear them all reversed. I enjoy it, the light-heartedness is such fun

I'm also changing lots of other gaskets, seals and bearings, as I'm in no hurry with the spare engine and would like not having to worry about a stupid oil seal leaking somewhere when I'm done.

I completely agree with this. If it's worth doing it's worth doing so properly that it'll not give you any issues when it's back together again. We share the same approach it seems

ALSO:
Bought: GSXR750L 1990 barrels and the set of pistons for it.
37950 miles/61074 kilometres and no fin damage.

Sorry to hijack the thread, but i'll share my findings when putting it together with you to help yours!

[Jimmie]

Nice one, now lets hope it all works out, for both our sakes.
I'm planing on doing some more trial fitting and measuring this weekend, and I shall continue to share my results.
Now lets just hope the weather permits me going to the workshop, which is located some 60km away from my home and my only transportation is an old Yamaha XT6Z, which can make for cold fingers when the temperature goes below 0C. But it's been a fun winter on that ride, no doubt it.

[Wolfe_UK]

Nice one, now lets hope it all works out, for both our sakes.

From the research I've done:
There's no problem putting the barrels or head on. The stroke is the same and there's something i found on arsenic's site about him using a pre-600 crank and case with GSXR 750 over-bored barrels and a post-750 head.

As long as the pistons fit on the stock 600 con rods, and can make up gaskets, and swap the GSXR cam sprockets for pre-600 ones, and put 38mm carbs on.. it all SHOULD be just a matter of tuning after that

[jcobb]

Looks good dude,,,you wouldnt have a good 600 motor sitting around by chance would ya

[Wolfe_UK]

Looks good dude,,,you wouldnt have a good 600 motor sitting around by chance would ya

Funny you should ask, I do have a spare 1991 one.. Think you might be a little far away to come get it though mate.

[jcobb]

Very true, i did just notice you live in the Uk

My b

[Jimmie]

Funny you should ask, I do have a spare 1991 one.. Think you might be a little far away to come get it though mate.

I was about to answer the same, I've got one, but I imagine shipping an engine from Europe to the US isn't worth the hassle.

jcobb - Good luck on with finding an engine though.

And the pistons do fit the 600 conrods, I've tried, and I can't think of any reason why the would have changed the small end size over the years.

[Wolfe_UK]

Jimmie, do you know if a 600F cam cover will swap with the 750R head? Or if it's possible to check if the next time you're at your workshop is before my parts arrive?
Tack!

[edit:more thoughts]

What exhaust were you thinking of using on yours.. GSF1200 header maybe?
Also, the crank case mating surfaces on the F and R were different.. Might need to make a custom gasket myself, or cut a 600 one to the larger bore to make it work.

[Jimmie]

The project is coming along, slowly... The spare engine is put on hold, again. I'm in the middle of building a XT600 engine, as it's for my daily commuter bike and therefor more important.

But I found some time to put the GSXF back together, cutting a few corners..
The front end is done, though I might swap the brake discs for a new set I have somewhere.



Other than that I've finally welded the mounting plates for the rear sets, fitted the swinger for the last time (I hope), and tons of small stuff.. Now I only lack a master link for the chain and I'm set for a test ride. Going to weld up the subframe tomorrow and pick up a rear sprocket and master link on tuesday. The rear sprocket I have at the moment is a 43T, which I think might be a bit small for the poor 600cc engine.


Sorry about the image quality, the last one is taken with my phone.