Swappability of parts between 650cc/700cc/750cc engines

Hey all, I have a 1984 KZ700 4-cyl. In the event the engine had some major damage and needed to be fixed/replaced, what parts would be swappable into it? Would a complete 750 motor bolt up to the transmission? How about a 650? Or would I need to get an engine and transmission together? Are the heads swappable?

I just don't want to be stuck searching for a 700 replacement if it comes down to it, as they are very difficult to find.

Thanks all
-J

Post edited by: masospaghetti, at: 2007/03/01 15:02

Ummm... The engine and transmission are all together in the same box, it's not like a Harley or pre-unit Triumph where you can change out just the transmission if it blows up.

If I understand correctly, the KZ700 is just a sleeved down KZ750. The only difference is the pistons and cylinder block.

Early 650s used a bicycle-type cam chain, later 650s and 700s and 750s used a Hyvo chain. 650s had slightly smaller valves.

In the highly unlikely event that your engine takes a pooper on you, you could bolt in an entire 750 engine. Or, if you wanted to, you could have your engine punched out to 810cc and use the Wiseco K810 pistons.

A well-tuned KZ700 is nothing to sneeze at! I like the way they look, too, they share a lot of features with the KZ750-L3, which itself is basically a GPz750 sans fairing...

What guitargeek said is 100% on the mark. If your engine totally craps out, you could simply remove it and replace it with a 750 or a 650. The electronics in the earlier 650s are different (points instead of electronic ignition, and different charging system components), so you would need to keep your old 700 electronics. These should swap right into the older engine, no problem.

750 and 650 parts are very plentiful. If you have the room to store things, I suggest you pick up a parts bike (these show up on Craigslist all the time, for under $200). You also see lots of parts on eBay at very reasonable prices. A few years ago I sniped a complete 750 engine on eBay from a local salvage yard for (get this) $65! The shipping charges made it unattractive to anyone who could not pick it up locally. The same issue holds true with parts bikes. If you see one locally, you can make a reasonable deal, often because the owner just needs to get it out of his yard.

Post edited by: apeman, at: 2007/03/01 16:57

I have an 84 700 engine,it's on my 78 SR it had an oil leak somewhere I couldn't see so I swapped it out with an 82 650 head that was identical except it had a tach fitting, the valves and combustion chamber were the same, it has 83 GPZ cams and the 700 intakes bolted on no problem, so most parts work just remember the the 700 has a hyvo chain so use parts from 81 up,I also took the 700 frame and combined it with an 81 650CSR so now another bike is underway,the easiest way it to keep the harness with the engine you are using

I also have a KZ700, and I'm currently trying to install a 2001 ZR-7 exhaust on it. I hoping this will fit, because the ZR-7 has almost the same engine. (it's a complete stainless steel exhaust)

Up until now I didn't have much problems to find parts for my bike. Most of the time I just by the stuff that fits the 750's.
The only thing I'm trying to find now is a clutch cable. But I have yet to go to the dealer and ask. I'm a bit lazy

Does anyone know how much HP a 700 makes. I couldn't find it anywhere. I'guessing it is right between the 650 and the 750's (about 70 HP)

Post edited by: Paling1, at: 2007/03/02 07:25

Post edited by: Paling1, at: 2007/03/02 07:26

This is my bike:

hmmmmm, let's try another one....

Post edited by: Paling1, at: 2007/03/02 07:33

:ohmy:

agawam, when timing the exhaust cam which position did you use? I'm putting gpz cams in my kz750 and the book says one setting (z6ex) for the gpz and z7ex for the kz. Is it dependant on the head being used or the cams? Thanks guys.

Bdog

Paling1 wrote:

I also have a KZ700, and I'm currently trying to install a 2001 ZR-7 exhaust on it. I hoping this will fit, because the ZR-7 has almost the same engine. (it's a complete stainless steel exhaust)

Mounting the muffler should be pretty easy, as all you'll need to figure out is where you want it to be and fab up a mounting bracket or two.
But even if the exhaust port diameters and spacing are identical on the KZ700 and ZR7, you will still need to figure out a way to bend the header pipes where they bolt to the engine without crimping and/or destroying the perty stainless steel coating on them - the KZ700 engine sits roughly at about 2~5 degress angled forward, and IIRC the ZR7 sits angled forward at about 15~20 degrees, which without the head pipes being "re-bent" would place the collector portion where the muffler attaches about midway into the oil pan. :pinch:

Not trying to discourage you here or say it can't be done (unless of course that inspires you to "get 'er done"), I think that the ZR7 stainless steel exhaust would look sweet on a KZ!

I'd just hate to see some guy (you) on the 11 o'clock news being arrested for hollering obcenities at passing cars and hurling tools and what-not into oblivion while trying to mount said exhaust.
:whistle:

Post edited by: RetroRiceRocketRider, at: 2007/03/03 19:16

Bdog wrote:

agawam, when timing the exhaust cam which position did you use? I'm putting gpz cams in my kz750 and the book says one setting (z6ex) for the gpz and z7ex for the kz. Is it dependant on the head being used or the cams? Thanks guys.

Bdog

See my post in the new thread you started.

Post edited by: steell, at: 2007/03/03 20:29

Paling1 wrote:

I also have a KZ700, and I'm currently trying to install a 2001 ZR-7 exhaust on it. I hoping this will fit, because the ZR-7 has almost the same engine. (it's a complete stainless steel exhaust)

Up until now I didn't have much problems to find parts for my bike. Most of the time I just by the stuff that fits the 750's.
The only thing I'm trying to find now is a clutch cable. But I have yet to go to the dealer and ask. I'm a bit lazy

Does anyone know how much HP a 700 makes. I couldn't find it anywhere. I'guessing it is right between the 650 and the 750's (about 70 HP)

There's a sticket under the seat on mine that says "Max power - 77 PS"

Thanks for the help everyone.

RetroRiceRocketRider wrote:

I'd just hate to see some guy (you) on the 11 o'clock news being arrested for hollering obcenities at passing cars and hurling tools and what-not into oblivion while trying to mount said exhaust.
:whistle: <br><br>Post edited by: RetroRiceRocketRider, at: 2007/03/03 19:16

Hmm, that sounds just like me....:evil:

Thank you for the comment about the angles of the engine. I have not thought about that yet... So maybe I'm going to sell the system soon....:silly:
Looking at these pictures:
bikez.com/motorcycles/kawasaki_zephyr_750_1994.php
bikez.com/motorcycles/kawasaki_zr-7_2001.php

I'm not sure if you are right about the 15~20 degrees though, the Zephyr and ZR-7 look about the same...

I have read this article: www.stud.fh-dortmund.de/~stefan.rathmann/tuningbericht.htm , saying it can be done on a Zephyr, so I was hoping to fit it to my KZ700 without too many problems... (Bending the pipes to make it fit, is not an option for me)
If too many problems occur, I will put back my Marving exhaust and stop bothering about the corrosion on it.