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Is it worth swithching to a K&N air filter?

Thoughts please

I put one in mine - but to be honest couldn't really tell a blind bit of difference. Best thing with the K&N is that it's washable and will probably outlast the bike.

Yes. You'll get a better throttle response,but you won't get anymore horsepower

When I got my Honda car, good condition/low mileage, some (many ) years back, I did a full service. I opted for a K&N because it was 'for life' and only cost two and a half times the price of a paper throwaway. So, figuring that I am going to keep this car till it powders away, K&N is a good investment. I also fitted a K&N in my jap four years ago for better breathing. I noticed the improvement then in the bike, but not the car.
I came to service the car again this year, thought about the air filter and the many years of tapping and brushing it clean, but not actually servicing it. So I bought a K&N rinse and oil service kit for it. Did the R1100S too.
REALLY noticed the improvement in the car's performance, but not this bike's.
My thoughts are, the K&N IS well worth the change, it does allow better breathing. I have just got hold of the SJ powerfilter, which is an enhanced K&N, with a MUCH bigger filter surface area. I have yet to try it. Later, I will post a summary of the mods I have done and their benefits.

It's viscious circle i'm afraid,i've run a SJ for over 12 months when Jeff brought both Lloyd and myself one over,it's another piece in the jigsaw puzzle,along with a decent pipe,dymags,brakes and as much Ti as you can afford in the weight saveing department,topped off with a power commander,does it make a difference??,Oh yes,i reckon i had a bigger shock rideing a stock S recently than some have here rideing the new 1200!!,the problem being it's now under geared.

Chris

oyster wrote: I have just got hold of the SJ powerfilter, which is an enhanced K&N, with a MUCH bigger filter surface area..

Is the SJ powerfilter not just a K&N, but for a differant model of bike ? If it is can you tell us the model number on the filter please as I might buy one and make up a CNC'd airbox top to link into the Lennies. If nothing else it should mean that the filter stays a bit cleaner as all the shite should sit in the bottom of the airbox instead of ontop of the filter, shouldn't it ????


Toodle Pip

theseadog wrote:Is the SJ powerfilter not just a K&N, but for a differant model of bike ?

I think I can help here!! I recently needed to replace the filter unit.

The K&N part of the SJ Powerfilter is K&N part number E-4450. It is produced for some kind of industrial earth mover (a sort of US JCB ) and as such is not available in the UK. It can be specially ordered in the UK, but takes a long time, even if you can find a K&N dealer who will place an order!!!!! One of the largest distributors of motorcycle K&N in the UK would not accept an order because the filter was not a motorcycle filter

It is much quicker (and easier) to deal with K&N in the US.

Interestingly that part number is apparently not known to SJ - or at least they would not tell me.

Confusingly, that filter is a round one which needs to be squeezed into the oval shape of the Powerfilter.

The number on the actual filter is not a part number, but a mould number for the rubber ends. That also caused a lot of confusion.

sandbar

Thanks Sandbar, clearly you know a lot more about the filter than me.
I will add for anyone that hasn't seen the SJ powerfilter, the K&N is bonded to a very nicely machined billet alloy plate. This forms the new top to the airbox to which the snorkel attaches.
And as for the muck dropping out to the floor of the airbox, computer says no. Everything that happens to waft in front of the open end of the snorkel while the engine is running, is rapidly vacuumed up, caught in the violent vortex as it rushes to meet the combustion process in the head. The filter just catches the big bits where they remain.

The joys of the internet eh!!!! the crap grit,small stones etc all drop to the bottom of the filter which is metal,i clean mine out by putting a vacum cleaner in,the filter its self doesn't suffer the clogging like the K+N as it's sucking through a filter thats 360 degrees,you can actually put your hand inside.

For anyone buying one just do your home work when you fit one and what ever pipe or system you have(do a plug check) the filter shifts a lot of air in comparison to the stock or K+N,but thats were the PC came up trumps.

Hi Chris

Thanks for the feedback, that's pretty much what I figured would happen with the worst of the detrius due to the design. Well sounds like another part of the jigsaw is about the fall into place, thanks for the details Nigel.


Toodle Pip

winger wrote:The joys of the internet eh!!!! the crap grit,small stones etc all drop to the bottom of the filter which is metal,i clean mine out by putting a vacum cleaner in,the filter its self doesn't suffer the clogging like the K+N as it's sucking through a filter thats 360 degrees,you can actually put your hand inside.

This is why I could never quite understand why the S's OEM filter housing was designed the way it was - the R/GS/RT airbox is very similar (albeit nowhere near as pretty/good quality) as the San Jose set-up ie a large-ish box with a large cylindrical air filter. As Chris does, I used to just hoover up the crap which fell into the bottom of the airbox on my GS and 1100R's. Amazing what you find in there aswell.

Get an SJ filter. It's a work of art & bargain for $200.
Mine was stolen along with my last S but I still pine for another.

The dollar picked not so long ago,but gone tits up again!!! there's never been a better time!!,saw yesterday the tourist rate was 1:80,blimey i've gone all funny,i feel a big bore kit comeing on!!

winger wrote:blimey i've gone all funny,i feel a big bore kit comeing on!!

I think you've always been a bit funny, now it seems you've gone all the way

Lloyd,

have you got nothing to do this morning? (Pot & Kettle spring to mind)