Rye...ZX9 engine in ZX7 Frame?

[Cage]

I have a 1996 Kawasaki ZX-7R and I think a 1994-97 ZX9R engine will fit. I want to know if this is the case and has anyone else done this?? Let me know. I was told you were the one to talk to about this...any help and pics would greatly be appreciated.

Thanks
Cage

[Rye]

Yeah it can be done. In a 91-95 it is nearly bolt-in. For a 96+ the front motor mounts require a relocation kit made by BRG racing. There is also a oil pickup plate that is added in the kit. It's a very easy process (I've done it already in my 95). The wiring diagram is identical in all zx7s and the 94-97 zx9. The 9r is virtually a stroked zx7 motor sharing ALOT of common parts. The biggest difference is in the redline on both motors. The 750 hits the limiter @ 12500 whereas the 9r hits at 11500 (makes sense with longer stroke). You will need the CDI/Brain/Blackbox for the 9r motor though. Guys have run the 7r box but potentially at the detriment of the motor since the limiter will kick in later (there is overrev in all bikes but 1k is starting to push it). I can give you any info. you'll need. Where'd you find the 9r motor.....rare beast?

[DH2ML]

Just side note...

Engine swaps are cool!

Back in 1995 I bought a brandy-new YZF-750. Rode it all that summer, and was lusting for more low-end torque.

After reading about several people who had transplanted an FZR-1000 engine into the 750 frame, I decided to give it a shot. That winter I removed the 750 engine, and bought an FZR-1000 motor & wiring harness from a wrecked bike in the back woods of Maine.

The transplant was a relatively straight-forward process, and when I was done I had the ultimate sleeper hot-rod. The best part was that I ended up selling the 750 engine to some guy in Colorado for more than I paid for the FZR set-up.

Other than my time (and what else did I have to do in the middle of a cold NH winter?), the swap cost me nothing, and taught me a lot about motorcycle mechanics.

I hope you have a similarly good experience. Go for it!

[Rye]

The 9r motor is the cheapest way to gain 20-25 hp. A friend in San Fran has his 96+ zx7 putting out 141hp to the rear wheel! That's power.

[Kip]

If only the bike wasn't 550+ Lb wet. I had a 95 ZX-7 that's a heavy bike.

[Cage]

Well, I haven't found the motor yet, but I will probably start looking this winter while the bike is "put away for the winter". I have seen lots of guys able to pull the bike up at 45 mph and ride a wheelie for some time, and mine just won't do it. I like the bike but have a need for more power. Anyone know of a 900 motor for sale??

As for the weight...it's 440 pounds, heavy for a 750, but it's a fun bike.

[Kip]

If your looking for a wheelie bike you got the wrong bike!!!!!
440 LB ? maybe if your taking about the bike without the motor in it.

[Rye]

I believe my bike is 485lbs wet. Maybe less now. Don't know what he's done to his, but on my exhaust alone I saved 28lbs! Still a fully capable bike as far as I can see.

[Kip]

Have you put it on a scale to see what it weighs? 28lbs in just the exhaust alone WOW!!!!!!!! Was the pipe filled with lead?

[Cage]

Hey, also what about the exhaust?? Will the header and pipe from the ZX7 work, or will I need another setup on that also??

[JJ]

I will post my bike weight sometime soon but I believe it's around 440 dry weight. Not to far off the new Honda 600RR.

[Kip]

I liked my ZX-7 because it felt planted, but there is no way the bike is 440 dry!!!!! I think it's something close to 500.

[Collision pro]

[QUOTE]Originally posted by JJ
I will post my bike weight sometime soon but I believe it's around 440 dry weight. Not to far off the new Honda 600RR. [/QUOTE

The Honda 600RR is 370 dry weight!

[Cage]

Kawasaki shows the 1996 ZX-7R to weigh 440 dry!!

[Kip]

OK, when they say "dry" that is with no oils, gas, water, ect what so ever in the bike remember.

[JJ]

The Honda 600RR is 370 dry weight!

That's funny Cycle World got 412lbs dry and and 441lbs with fuel just to let you know where I got my info from. 370lbs might be in full race trim but not street. And out of my Clymer Manual claims the 96-03 Ninja ZX7R is 511lbs loaded with all fluids. And everyplace else I have seen on-line says around 200-203kg which equals 440-447lbs dry. The 93-95's are actually claimed lighter than the 96-03's according to Clymer. But if and when this crappy weather ends I will top off with all fluids and weigh my bike on the dump scales.

[Collision pro]

Originally posted by Cage
Kawasaki shows the 1996 ZX-7R to weigh 440 dry!!

That 70 pounds is alot of weight. I have a Tl1000r that is a pig, I took off everything I could and it's still a pig! It's hard to lose weight!

[Collision pro]

The Honda 600RR is 370 dry weight! [/B][/QUOTE]

I got that of Honda's site.

[JJ]

I got that of Honda's site.

I know the manufacture seems to come up with these magical weights and that is why I used my quotes on weight from a source (Cycle World and Clymer). Not saying they are right either but usually print in the next issue if they see a misprint (Cycle World).

[Kip]

The difference is some say "dry weight" and mean no fuel in the bike. Others say "dry weight" and mean no fluids in the bike at all like fork oil, coolant, oil, fuel ect.

[Rye]

Kip, I'm running a full Muzzy Ti exhaust from tip to tail. It's 8.something lbs. The stock exhaust is 36lbs. That was a huge performance gain in my book (aside from flowing better). I've also eliminated passenger pegs, part of subframe, rear seat and assoc. plastics and mechanisms. 9 series race battery. Aluminum sprocket, PM chicane race rims, EBC prolite rotors, etc, etc. I view "dry weight" as w/o fuel only.

Cage, YES. The headers will work (actually the whole system will). The 94-97 zx9, 91-03 zx7 all are interchangeable. The Muzzy zx9 pipes are 2 1/8 diam whereas the zx7 model is 2", but this still does not effect it bolting up.

[Kip]

Rye, I agree with you I had PM rims for my ZX-7 and they really did save a lot of weight. I thought the stock rear rim was solid metal.

[Cage]

Originally posted by Rye
Cage, YES. The headers will work (actually the whole system will). The 94-97 zx9, 91-03 zx7 all are interchangeable. The Muzzy zx9 pipes are 2 1/8 diam whereas the zx7 model is 2", but this still does not effect it bolting up.

Thanks a LOT man, you have really been a lot of help. I am going to start looking for a 900 engine and probably a big bore kit to go with it.