GSX-R 750 in a Kat 750

[89katana750]

So I have an oppurtunity to put a 1990 GSX-R 750 in my 89 kat 750. My motor blew at 105,000km and the gsx-r has 30,000km on it. Can I use my stock exhaust and carbs from my kat? Anything else I should be aware of?

[Mr. Clean]

Everything *should* work from your Kat. You might have to play with the air/fuel mix screws in the carbs. I would adjust the valve lash before you put the Gix engine in the bike. Have fun.

[The CyberPoet]

Just make sure you grab the CDI and coils from the replacement engine as well -- some of the oil cooled GSXR engines from that era were "slingshot" engines (I don't recall the years specifically), which had the same displacement but different bore/stroke (longer stroke). As a result, I'd expect the CDI is probably not interchangable on those units with your Kat's CDI. If the bore/stroke is the same, your existing CDI can probably drive it, but you'd still be best off using the CDI that originally shipped with each engine.

Cheers
=-= The CyberPoet

[Mr. Clean]

Yeah I forgot about that. The 88-89 GSXR 750 was the sling shot, and I believe your Kat 750 was a sling shot as well. I'm using a 2002 Kat 600 CDI on my 771 engine I built with out any problems though.

[01Katman]

Mr. Clean you don't have any problems revving past the 11250 mark or do you. It seems like these engines should be able to turn more rpms?

[Mr. Clean]

No problems at all. My red line is around 13,000, but I try NOT to rev that high though.

[89katana750]

Thanks for your help guys. The guy sold the engine to someone else though. Argghh. It didn't come with anything but the engine block though, so no cdi.

[89katana750]

So I got an e-mail the other day from the guy who sold the engine and it wrote that the buyer skipped out on the engine because he didn't want to pay for shipping. The seller sold it to me for $130!!!! because i picked it up. The only thing I am concerned about is that there is a hose coming out of the 4th intake boot and I'm not sure where that can go. Any help would be great.

Im excited to hear it!

[The CyberPoet]

The only thing I am concerned about is that there is a hose coming out of the 4th intake boot and I'm not sure where that can go. Any help would be great.

If it's actually fitted to the boot (and not the carb's neck for the boot), then it would appear to me that the guy was running a Scot Oiler and using that as the vacuum source. Plug it over. If it's running out of the carb's neck for the boot, and there is already one on the #1 carb for the petcock, then I'm clueless, but my advice would remain the same: plug it up to stop the vacuum leak.

Cheers
=-= The CyberPoet

[89katana750]

It's running from the carb boot, #4 carb only. I'll plug it up, that was my initial move. Thanks for the help. All I have to do is just reseal the oil pan and I can put her in. and might as well do a valve adjustment while the engine is still out.

[Guest]

Let me know how this works out for you, I have an 88 katana 600, and was thinking about upgradeing the motor to a 90 gsxr 750 or 600, .

[89katana750]

I'm putting the engine in the frame maybe on wednesday. I noticed that my oil cooler lines may be too short for the 90 gsx-r 750. That is the first problem so far. I'll keep you updated. I feel something with the clutch cable maybe being an issue too since the cable has to be on the opposite side than the katana.

[89katana750]

anybody know where I can get a set of oil cooler lines for the 1990 gsxr 750? 1990 was the year where they curved the oil cooler a bit and put the lines farther back at the bottom. So mine are too short.

[Black_peter]

Wow..
Ebay?
What about just extending the existing ones?

[The CyberPoet]

anybody know where I can get a set of oil cooler lines for the 1990 gsxr 750? 1990 was the year where they curved the oil cooler a bit and put the lines farther back at the bottom. So mine are too short.

I've got a 98+ Kat 750 oil cooler here that might work for your application... PM me if you want it ($65).

Cheers
=-= The CyberPoet