• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Will '79 GS 1000 cylinders and pistons fit on a '78 750???

tkent02

Forum LongTimer
Past Site Supporter
What is the bore and stroke of a 1000?
Will this work with a little persuasion or is an 850 top end the best I can do?
Anyone with personal experience with this?
Thanks,
Tom
tkent02@gmail.com
 
The GS1000 bore is 70mm x a stroke of 64.8mm. I have no idea if this is a possible swap. Ray
 
No..it is not possible. Just put a 1000 motor in it.....Billy
 
I've never heard of anyone attempting this particular swap. I do own a 79 750 & 3 78 1000s, so I can tell you that there are a lot of potential problems.
1. Cutting the cases to allow the 1000 block to fit. (This is a definite must do.)
Expensive machining & full teardown of engine required.
2. There's a 8.4 mm difference in stroke. How did Suzuki compensate for this?
Connecting rod length, piston pin to crown height & block deck height may be different.
3. Combustion chamber size difference. Using the 750 head is asking for trouble.
The combustion chamber diameter & volume is significantly smaller than the 1000 bore. Piston to valve contact & or piston to head contact is a probable issue.
The 1000 head will solve those problems, but the compression ratio will be ridiculously low. This means milling the head/block to raise compression. This means more potential piston to valve clearance problems.
4. Any change in deck height means you'll have to adjust the cam timing. You'll need adjustable cam sprockets & a degree wheel.

I hope by now you realize that this isn't a good idea!


Terry
 
My advice is to use 850 parts. I'm putting together my 78-750 2-v using 850 cylinders, head & pistons. All it took was a little grinding on the cases with my Dremel to get the 850 stuff to work. So this is really an easy swap.
What I do need to know is how much to mill off the stock head & block for a increase in compression. The 850 head will allow me to use modern cv carbs, I have a bump in displacement & (hopefully) a good boost in power as well when accompanied with a header & rejetting.

Paul
 
Back
Top