Good morning all.
Is there any benefit in replacing a standard air filter on a V85TT for a K&N filter? Any thoughts or experiences would be much appreciated. Mark
I’ve a K&N and a Mistral velocity stack I fitted and removed. Seemed to make the bike a bit too noisy for long trips. Fitted for about 3,000miles. Difference in performance, umm, probably a bit but nothing dramatic as all these tweaks are.
I might be interested in selling both as I don’t think I will refit them.
I’ve also got a Mistral Conical Carbon silencer that I fitted and removed. Again too noisy for long days riding - it was my pillion who found it noisy really. This was fitted for quite a bit longer but being carbon fibre and stainless remains almost as new. I’d sell this too if you are interested.
All from a 2019 /E4 bike, but I’m 99% certain they fit E5 bikes.
I don’t see how the velocity stack would increase noise, decat definitely does especially on euro 5 bikes.
I used to be a great fan of K&N, but I wouldn’t now, K&N are not superior to OEM paper filters, this has been laboratory flow tested, there’s a web page about it somewhere.
Thank you for the feedback. I think I’ll stick with the paper filter.
Tbh it was the K&N I was referring to about noise. Definitely more induction noise.
that’s the only mod i didn’t do, is there any advantage to it regarding servicing intervals ?
If fuel injected then there is no real difference had.
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I only bought theK&N as Mistral were pushing the need for a less restrictive filter to go with the velocity stack. They sold another brand but I figured a K& N would be just as good.
Apart from claims of increase in power the big advantage of K&N and the like is extended service intervals and then cleaning rather than replacing. I used to commute 500miles a week on a Honda Transalp and fitted with a K&N it made servicing a breeze as the air filter wasnt particularly accessible. Just drop oil & filter 2-3 times a year. Plugs annually, wash and oil air filter every 18-24 months. Sold that bike still running strongly with 125,000 miles on it.
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What I remember is the lab tests showed that the K&N (and another brand) wire gauze and cotton were indeed less restrictive to air flow initially, but then quickly started to clog up, ending up worse than OEM paper in the same amount of time and dust throughput. My own experience was that the cotton is never as clean after first washing as when it was brand new, and is always a dirty grey colour. Also the cleaning fluid and oil are not cheap so seems like K&N just want you to keep buying their cleaning fluid and oil. Also it was too easy to over-oil the cotton, then it’s clogged, and has to be cleaned again. The whole thing was a rigmarole and I remember whole Saturdays messing about cleaning the things then waiting for them to dry in the sun before putting the oil on (the cleaner is rinsed off with water). Then after some years of use, went to take them off for a clean one day and all the cotton had completely disappeared, presumably rotted then sucked through the engine(!) leaving just the gauze behind which wouldn’t stop sand getting in. So no they don’t last forever.
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OEM it is then! Thanks for all the feedback and opinions.
I have the v7 850 and have both the K&N fliter and velocity stack fitted. Noticable increase in smoothness and throttle response but no more noise. I guess it just depends on the individual machine and personal preference. I also have a BMW R1200gs with a K&N filter. No difference at all in engine performance however I now get 10-15% improved fuel economy