GS-Riders International

I ordered my Pipercross airfilter from Vancosports. I paid S$ 165 / Euro 79 / US$ 109 delivered to my doorstep in Singapore. The company went into summer holidays after I placed my order. I was duly informed about a delay but not how long it would take. Everything else worked very well with Vanco, as usual.

The price above is for a complete kit, which includes
- pop-in cone panel filter for the R 12 GS
- filter maintenance kit = cleaner bottle 500 ml + filter oil 200 ml aerosol can (this should last for years)
- warning label for pasting on the air filter box, letting the service person know there is a reusable filter, plus some service instructions (of course I forgot to paste this useful sticker onto the bike)

The Pipercross air filter came oiled and ready for use. Surprising little oil, but good to know for future reference. There is also a warning written on the instructions regarding the use of too much filter oil.



Dual density foam about 10x magnified, red foam on the inside and grey for the outer side:





Installation on the GS is very easy. Remove the side panel, the aluminium tank cover, the seat and the small black triangle cover:



Striped down right side. The red marker points to the air box:



Two clamps hold the air box cover, which is attached to the snorkel. Press the rear side of the clamp inwards with a finger, and then pull the clamp out. Eventually you have to use a screw driver blade to pull it into unlocked position.






The snorkel looks like an elephants trunk. There is a nipple in the front part of the snorkel which locks into a rubber grommet. With the left hand I pulled on the air filter side, and with the right hand I pulled the nipple part out:



There we are:



Squeeze the air filter a bit and pull it out sideways. The air box looked clean after 12,500 km / 7,800 m:






I cleaned the snorkel and the contact surface of the filter frame. The Pipercross goes in well, and is a perfect fit:






Assembly is done in reverse order.


How is it?
The intake noise has not changed much. There is a mellow bassy undertone present now. But if someone don't know the GS he would never notice anything I believe. Riding I can say there is a difference, but not relevantly so. I can't say much at this point, as I only rode 80 km. After I do my usual round trip which I use for my testing rides, then I should know more.

Some additional notes.

The inside of the snorkel showed marks of water collection:



I drilled a few 4 mm drain holes:




The original filter did 12,500 km / 7,800 m. It was never cleaned. Remarkable is the lack of any rough debris. This fat engine breathes through these tiny holes:



The inside of the filter was flawless:






As I said I did not find any rough debris or bugs on the filter or any other part of the intake system. Overall everything was surprisingly neat. Now I see the point that BMW just asks for changing the filter every 20,000 km. But I still would feel more comfortable with a dirt screen in front of the filter. So that is what I am going to do next.

Quoted

Originally posted by Peter

How is it?
The intake noise has not changed much. There is a mellow bassy undertone present now. But if someone don't know the GS he would never notice anything I believe. Riding I can say there is a difference, but not relevantly so. I can't say much at this point, as I only rode 80 km. After I do my usual round trip which I use for my testing rides, then I should know more.

- The weak spot in engine torque around 4500 - 5000 rpm is lesser.
- Above that the engine revs up easier.
- That's all, no other diff whatsoever.

9,500 km / 6000 miles later with the Pipercross







Corse stuff in the air filter box


Fibres and dust in the sink after washing the filter

Inside the air filter box with OEM air filter used for the first 10,000 km. The oil on the bottom of the air box is from overfilling engine oil, when the workshop was doing the 10,000 km service. I left that all alone.



At 19,500 km, using the Pipercross air filter for 9,500 km

John, as I see it there is no way the filter could get seated wrong, as how this part is constructed at the GS. The mounting flange had grease.

May be you got cleaner air in your area?

I don't see how this foam has much filtering capabilities without the semi sticky oil. Worst is it seems to have problems with the bigger stuff (see the fingers photo), while the fibres and dust seem to be filtered better (see the sink photo).

Now I cleaned the filter case, and this time I also removed the oil sludge. I will give it another try, because I like that the 4500 rpm dent is lesser. As well I heard that foam filters do improve somewhat when they get older.

But it is clear to me: Even one of the most well made air filters from the aftermarket still can not reach the simplicity and efficiency of a cellulose filter.

Two, the grey and the red.

Another 5,000 km with the Pipercross air filter. Here is my very short verdict:

1. Found again too many particles in the air-box. Can't show you, because I don't have a camera at the moment.
2. I did a test ride after I installed the factory paper filter back. I was almost blown away by vastly better roll-off power. The engine does have generally a more "torquie" feel, simply more power below 4,000 rpm.

If you ask me, all this with the reusable aftermarket filters is nothing else than BS. Overall nothing is as good as a factory filter. So far this was true for all my motorcycles where I tried a reusable filter.

Mileage 41,000 km, using OEM air filter for 16,500 km:

OEM air filter after 16,500 km. 6,400 km of this was a tour through Australia with plenty bugs, a couple of hundred km dusty gravel road included. The filter was never cleaned.



Dirt collected, has actually a reddish colour.

Quoted from "johnofchar"

If that Pipercross was sealed correctly, there is no way that grit would get through. May want to try a little waterproof grease around the mounting flange.

My opinion: It is not possible for a filter which is "see through", such as the Pipercross for the GS, to be filtering dirt efficiently. There will always be particles shooting straight through.