Air filter to get '79 xs 650 running

GaryS-NJ

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I just acquired a front end crash stock '79 xs 650 that's been sitting. I'd like to get it running before changing air filters or jetting. I did read the tech section and will go with Uni foam filters (more on that) AFTER I get her running.

So I removed the bowl drain screws and a sweet black ooze came out. Funneling fuel and then chem dip into the carb fuel lines hasnt filled the bowls so I guess the float needles are plugged and carbs coming off. The air filter foam was chewed off and made to housing by mice so I guess to after i get the carbs cleaned i will need filters.. i was gonna just delete the air boxes but i think quickest way to an operational test would be to wrap the stock air filters with polyurethane foam (like a Gary uni). Im sure it would run without the foam but I think a little intake restriction like as stock filter might help.

I dont think buying stock air filters or aftermarket replacements makes sense as the airbox probably coming out to facilitate jetting for Uni airfilters and open exhaust (yes, I will be that guy).

As for the Uni foam filters, any recommendations?? I see short with one layer foam and long with two stage foam and was thinking long might fit if angled out then I can run two stage foam.. or is there a slick 2:1 filter I might try? I saw some supposed to be good for in line 4's with VM carbs..
 
You can start and test run the bike without any filters, it won't hurt anything for the limited run time you intend to do. The UNI filter of choice for your BS38 carbs is the UP4200. It is 4" long, the longest you can fit in there between the carbs and battery box, and has a 2" inlet I.D. It fits on the BS38 carb like a glove .....

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You could also use the dual layer version, the UP4200ST, if you like, but it costs a few dollars more and I really don't see the need for it. I do have them on my other 650 but that's simply because I acquired them cheap from a guy who couldn't use them on his bobber project.

BsA4RKJ.jpg


They are nothing more than the same black foam filter with a coarse foam red sock over them .....

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