• 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.

OEM paper VS UNI foam filters

chuck hahn

Forum LongTimer
Past Site Supporter
What do you guys think. UNI foam filters or OEM paper filters for my 77 750?? UNI is what I have now and I was thinking about going to the paper again. K&Ns are just way too expensive.

The UNI foam about 3/8 to 1/2 inch thick. I was wondering if that thick a foam could maybe make it run a bit on the rich side form not flowing adequate air.

Or do you think the foam is about the same as the stock paper style? I think the foam may be a tad more restrictive myself.
 
My 77 750 has a foam filter that is OEM. It has a metal frame with a washable foam filter that can be removed from the frame if you remove two screws. That is what the service manual and the parts fiche show.
 
Mine was built August of 76 and it had a paper filter like the 77 750 fiche shows. Its an element not a foam insert. See the K&N brands and that whjat the OEM one I took out looks like..but paper. We can agree to disagree on this one. I know what I took out of the bike. I took the paper one out and got an UNI filter foam but as I said I think its a bit morem restrictive based on how I feel it respond. Now..without anything there..it feels a lot crisper when I roll on the throttle. This is why i posted the question.
 
Last edited:
I'd use the uni. Flow rate should be similar/same as stock because foam filters like that were standard on most all GS's.
 
Ed..then where did the paper one I took out a while ago come from?? It looked just like the K&N ones except it was the normal paper filter media. And if as you say was standard in most GSs, then why arent the round filters for the 1000s foam..or at least foam wrapped?? Maybe I will just order the stock one on Boulevards site and see what shows up.
 
Chuck, so far I've owned a 450, two 550's, two 850's, and most recently two 1000S's. All those bikes used a foam filter other than the 1000's.

The service manual for the GS750 states to "clean" the air filter every 3000 miles. No mention of replacing it. The 750 and 850 share the same filter, and on the 850 it's foam.

I have no idea if the original 750 filter is paper or foam, and don't really care to be honest. I just know the foam filters are fine.
 
Last edited:
Chuck, did you buy your 77 new from a dealer? I did, and mine had a foam filter. Polyurethane to be exact. It attaches to a metal frame. Do you have a 77 owners manual? I do, it came with the 77 750 that I still own. On page 37 it shows you how to remove, clean, and oil the foam filter, including a photo. How about an original factory shop manual printed in Japan? Yep I do. Page 16 shows how to clean the foam filter with gasoline including the correct way to wring it out before oiling it. Have you worked as a service tech for a Suzuki dealer? I have, and have cleaned or replaced dozens of these filters as they are also used on most 850/1000/1100 shaft drives as well as all 77-79 GS750's. As for the parts fiche, you need to look a little closer. Part no 13780-45010 is the complete assembly, the metal frame and foam filter. Part number 13781-45010 is for just the replacement foam filter. For the record, I have both of these parts in stock, on the shelf, in factory boxes with part numbers attached. I still have my 77 and three 1979 GS750's, N,EN, and LN. Someone who owned your bike before you must have replace the OEM filter with an aftermarket paper filter. That doesn't mean it came that way. Getting back to your original question. A Uni filter will work fine as will a stock FOAM filter or a K&N.
 
I would stick with the foam as that is what it had when it was new. I think the Suzuki engineers may have had pretty good insight on which filter would be best. Either way i don't think it matters a lot as long as the air is clean...
 
No i didnt get it from a dealer..it was the way it was when I got it. I cant speak to who put the paper filter in..all I know is it was there when I got the bike. When I replaced it ( due to it literally being black with dirt ) they gave me this UNI filter at the dealership in Warren MI.

And I do not have any manuals. But i know Bikecliff has them...which I never even thought to look there before I asked the question. I will check there..Thanks for the info.

Can I get a K&N refill kit and use that spray on oil?
 
Back
Top