800GS Uni Filter

[chadams]

I've got the Aus kit and cut my snorkels, the USA unifilter kit has plugs for the snorkels so no need to cut.

I benefit I found from cutting the snorkels is when crossing water instead of going into the airbox it now goes into the void :-)

[The Griz]

http://advrider.com/forums/showpost....&postcount=142

http://advrider.com/forums/showpost....&postcount=256


Uni USA (the real Uni ) F800GS NU-7308 filter:


































http://unifilter.com/

F800GS NU-7308

http://unifilter.com/online%20catalog/streetbmw.html


The Uni Aussie filter kit was and still is specifically designed for the R1200GS and not the F800GS. When using the Uni Aussie kit on the R1200GS no cutting is needed to use the pre-filter socks. Also, the R1200GS airbox is deeper, making the filter fit right without having to be forced. This is all due to, once again, the fact that it is designed specifically for the R1200GS. Then Uni Aus decided to be cheap and claim the R1200GS one will work well with the F800GS. It does not. It'll work when forced (cutting plastic and squishing the air filter in), but it is not specifically designed for the F8. The filter is too tall so it does not sit well in the F8 airbox with out being squished or forced. And in order to use the Uni Aus pre-filters you need to cut the plastic on the bike! Far from ideal.

Now, on to the UNI USA F800GS kit. Firstly, it was designed for the F800GS solely. The filter is shorter so that it sits in the airbox without having to be forced or squished, and the pre-filters can be used without having to harm the bike. If you don't want to use the pre-filters, you can just use the filter only. I've been doing that for quite some time now, and in some very dusty conditions. No prob.

Lastly, cost. Uni USA F800GS NU-7308: $35. Uni Australia R1200GS NU-7305: $90-105 (depending on where you look).

[stephen.stallebrass]

Have any of you UniFilter guys rejetted your carbs? Apparently it's reccomended by Uni in the FAQ.My F8 is due a service and I'd decided to go over to the Uni foam air filter but if I have to piss about rejetting carbs I'll not bother... is it really that necessary???

Nevermind, just remembered I'm a dumb ass and that it's fuel injected, LOL!

[stephen.stallebrass]

Have any of you UniFilter guys rejetted your carbs? Apparently it's reccomended by Uni in the FAQ.My F8 is due a service and I'd decided to go over to the Uni foam air filter but if I have to piss about rejetting carbs I'll not bother... is it really that necessary???

[señormoto]

Originally Posted by stephen.stallebrass

Have any of you UniFilter guys rejetted your carbs? Apparently it's reccomended by Uni in the FAQ.My F8 is due a service and I'd decided to go over to the Uni foam air filter but if I have to piss about rejetting carbs I'll not bother... is it really that necessary???

F800GS doesn't use carbs - it's EFI. They adjust automatically, but I suppose if you had a power commander or other EFI tuner you could adjust the fuel mapping after changing filters or exhaust.

[stephen.stallebrass]

Originally Posted by themattreid

F800GS doesn't use carbs - it's EFI. They adjust automatically, but I suppose if you had a power commander or other EFI tuner you could adjust the fuel mapping after changing filters or exhaust.

I was just coming to edit/delete my dumb ass question here but you beat me to it, LOL. A comment in the other thread reminded me that its fuel injected.

Originally Posted by johngil

They forgot to put the carbs on my bike I guess.

[stephen.stallebrass]

Had my Uni foam filter come from USA last week, not got round to fitting it yet though. Might save it until my trip in June, which is when I'll really need it. For now I'll leave my K&N in for now as I'm only riding roads for commutes... I didn't realise it came with the stubby pre-filters, thought I was going to get the longer pre-filters, a la 1200? You reckon these stubby ones will be as effective as the longer ones? Have to say Uni USA were very helpful, patient and good value. NB: I didn't get charged anything at UK customs either.

[Dockstrada]

Don't bother fitting the pre filters they just get sucked into the airbox once they get more than 10km of dust in to them, unless you're the leader but not always possible useless if you ask me.

They end up just like the pic once blocked with dust they block the air flow to the engine

[Zigomo]

Hi from Italy.
I would question about the possibility to install such type of UNI prefilter on my BMW F650GS, twin not funduro...is that possible? Have I re-arrange electronic mapping? My motorcycle is standard not modified

Zi go mo

[stephen.stallebrass]

Originally Posted by Dockstrada

Don't bother fitting the pre filters they just get sucked into the airbox once they get more than 10km of dust in to them, unless you're the leader but not always possible useless if you ask me.

They end up just like the pic once blocked with dust they block the air flow to the engine

Good to know, thanks. I wonder if there is any way of using the 1200 Uni Aus pre-filters without cutting the snorkels. I wonder if pre-filters are even necessary?

[Ducksbane]

Originally Posted by stephen.stallebrass

Good to know, thanks. I wonder if there is any way of using the 1200 Uni Aus pre-filters without cutting the snorkels. I wonder if pre-filters are even necessary?

There is a way ... but really , I had trouble with the concept of cutting the snorkles at first, but I did it years ago and I have no regrets. Aprt from getting the prefilters to work well, it gives you a lot more room in there, and there is the possible improvement in water crossing ability. I noticed no discenable difference in power and you can't tell the bike has been "defaced" unless you take off the plastic.

The prefilters work really well ... I recently went on a very dusty ride with a lot of other bikes. There was a lot of dust in the prefilters when I removed them (easy to do with the cut snorkles) but the main filter was good. This meant that after the really dusty section I could just pull out the prefilters and I was good again.

Now you ask ... how do I use the prefilters without cutting the snorkles? I'm a bit reluctant to tell you this ... US Unifilter seem to be good at "borrowing" other peoples ideas and not even acknowedging them. I had a friend along on this ride who wanted to use the prefilters without cutting his snorkles and what he did was find a couple of cheap plastic funnels whose spout would fit down the snorkles and cut out a section (probably about an inch long), cut the prefilters down a bit and insert them in the snorkles such that he could reach the funnel parts and extract the prefilters by pulling out the "cones" made from the funnels. It worked very well and I think the only down side was that the power might have been reduced a bit more this way. It's a great idea and I don't know why no one else thought of it!

I certainly hope no one steals this for commercial purposes ... without appropriate compensation and fame for my friend! I hope he doesn't mind me telling you, but he's a generous soul, so probably not.

[señormoto]

Originally Posted by Ducksbane

I certainly hope no one steals this for commercial purposes ... without appropriate compensation and fame for my friend! I hope he doesn't mind me telling you, but he's a generous soul, so probably not.

Too late, I just stole it to benefit myself commercially.








Seriously though, let's not get started on the patent industry. Personally I write OpenSource software and therefore give away my hard earned code for free; coming up with a funnel for a pre-filter isn't going to make UNI millions of dollars off the couple hundred F800 filters they sell a year. Knowledge should be free, and anyone that sees this new improved UNI stolen idea filter could just go to the auto store and get a couple of funnels and reverse engineer themselves their own system without paying UNI. Communism FreeMarket FreeWill Theocracy SoapBox etc etc etc.

[Ducksbane]

Originally Posted by thematt

Too late, I just stole it to benefit myself commercially.








Seriously though, let's not get started on the patent industry. Personally I write OpenSource software and therefore give away my hard earned code for free; coming up with a funnel for a pre-filter isn't going to make UNI millions of dollars off the couple hundred F800 filters they sell a year. Knowledge should be free, and anyone that sees this new improved UNI stolen idea filter could just go to the auto store and get a couple of funnels and reverse engineer themselves their own system without paying UNI. Communism FreeMarket FreeWill Theocracy SoapBox etc etc etc.

I know it's not worth a patent, but I would be cross if someone like either Unifilter started doing this and claimed it was their idea, especially as it's not mine either.

I therefore propose that having made this idea open source that it be known as Phil's mod!

[JRWooden]

Originally Posted by Ducksbane

I know it's not worth a patent, but I would be cross if someone like either Unifilter started doing this and claimed it was their idea, especially as it's not mine either.

I therefore propose that having made this idea open source that it be known as Phil's mod!

Snap a picture of it post it here and that pretty much puts it in the "public domain" and would make it more difficult for UNI or someone else to patent the concept of the "easily removable prefilter" ....

Of course that does not prevent them from putting it in their products and telling everyone how clever they were to think of it ...

prehaps a prefilter cut in a conical section that stuck out the front a bit would offer more filtering area and also be easy to grab and remove ... something shaped kinda like a mute for a trumpet?

http://www.amazon.com/gp/product/B0002DV6J4

PS: Does anyone recognize this air filter .... seems to have a lot more surface area than the others I've seen....

http://www.advrider.com/forums/showthread.php?t=749070

[jeff800gs]

Originally Posted by SCVGS

I got some free dyno time today and found that the little foam plugs that Uni gives you as prefilters cost me 3.2 peak HP! Remove them and its equal to a stock filter. Drill three 1" holes in the airbox lid and gain 2.6 peak HP and the torque rises a bit below 5K RPM. YMMV

At some point I lost one of my prefilters so I ended up throwing the other one away. When I went to go and clean the filter I had found the other one had been sucked into the snorkel. I decided that I would follow SCVGS lead and drill three 1" holes in the air box cover and then cut up the prefilter into three pieces and stuff them into the holes. I haven't had it on a dyno but it sounds much better like is not gasping for air anymore. I didn't oil the plugs I just couldn't have open holes in the airbox.