Air box gasket alert

[lberkhei]

I started cleaning my carbs yesterday, Since I hadn't checked the air filter since I bought the bike about a month ago, I took the opportunity to look things over there, too. It's basically the stock setup, although one of the former owners obviously bought the K&N stock filter replacement unit. But, as I looked a little closer, it became evident that there was a gasket missing, and I wasn/t getting any filtering at all. There must have originally been a fairly thick and compliant gasket attached to the top of the air box, for the filter element to seat against. I have to assume the material originally used deteriorated over time, and was sucked through the engine piece by piece! Frightening thought! But anyway, those of you with GS750's or other models using the same air box/filter arrangement (I have no idea if there are any, or which ones, but I suspect it's not a totally unique arrangement) might want to check yours.

Closely related - I haven't checked for a K&N web site yet; I may be able to find the answer there. Question is what are the maintenance/cleaning guidelines from K&N for this filter unit? I know most of their stuff is washable/reusable, but I don't have any first hand experience with their filters.

Thanks

[focus frenzy]

I have the original K&N stage one filter(replaces stock) in my 80 1000g and it was also missing the foam gasket. I think it is safe to say that it is pretty common for the seal to be missing.
It is pretty simple to fabricate a replacement seal/gasket.

as for cleaning them, it is best to use the K&N "recharger" service and care kit, it will asure long life and the best filtering.
the kit comes with the cleaner in a spray bottle, you spray the cleaner on liberaly and then alow it to soakin for ten minutes, then using low presure water rinse it and the dirt out from the inside out.
then after alowing the filter to dry completly you spray the filter oil (comes in the kit) on evenly then reinstall.

I do not know what the recomended interval is for motorcycles but for the K&N filter in my car it says to clean it every 30,000 miles.
the web site for K&N is: www.KNpowersports.com

you can get the "recharger" kit at most performance autoparts dealers.

[lberkhei]

Thanks for the info. I did fabricate a new gasket right away; now I need to track down the K&N recharger kit. Got the list of local dealers from the K&N website; should be in good shape, at least with the air filter. Now back to the carbs... :?

[Jay B]

My 81 850 has a gasket attached to the top of the stock air filter. It's about 1/4 inch thick and about 3/4 to 7/8 of an inch across.

[Anonymous]

wow! same problem!

wow! i was wondering tonight how to make a gasket for the very same thing!

if you guys don't mind me asking, how did you guys make one? i'm curious to what materials or shopping list to use... any details would be greatly appreciated.

thanks guys! this forum has been a bike saver for me!

hall

[earlfor]

Re: wow! same problem!

When I bought my GS750, the rubber seal on the airbox filter was also missing and since it is only an air seal, I fabricated a new gasket from an old mouse pad which just happens to be about 1/4 inch thick (just what I needed).
I glued the gasket to the element box with contact cement and it has been fine for the last 7000 miles. Just checked it today as a matter of fact. :-)

Earl

wow! i was wondering tonight how to make a gasket for the very same thing!

if you guys don't mind me asking, how did you guys make one? i'm curious to what materials or shopping list to use... any details would be greatly appreciated.

thanks guys! this forum has been a bike saver for me!

hall

[Anonymous]

I use self-adhesive draught excluder strip which I get from my local DIY shop (do you have DIY in the States? I mean a hardware store.)
Its exactly the right size and compliance for a 77-79 750 airbox. I was worried how it might stand up to oil and petrol, but its still going strong after 2 years.

[lberkhei]

I used the self adhesive draft sealer stuff, too, with some concern for how well it will hold up. Glad to hear someone else is having success with it !

Earl, I did a real "DUH" when I read your mouse pad solution; that was the kind of material I had in mind, but using a mouse pad escaped me , and of course I've got several extras laying around. Still think it's better than what I've used, so if I have any problems, AND can remember it, a mouse pad will be my next source of gasket material.

[Anonymous]

I also used the sticky foam sealing tape to fabricate a gasket for my filter. Its been on for 20K+ miles and still working great.