K&N air
04-01-2013, 01:43 AM
#7
Out of my mind, back in 5
MotoGP
Join Date: Nov 2006
Location: Skurup, Sweden
Posts: 6,109
Well... This is on the top three list of debated topics around here...
The K&N improves airflow, yes... But the VTR is a finicky beast, and just increasing air with no other changes usually only decreases mileage... Some have managed to tune their bone stock bikes with a K&N to their satisfaction, usually with a lot of time spent... Some have just slapped it in there and called it good... Some of us have spent time and money trying the K&N and given up on it...
The closest you will get to a consensus around here is probably that on a bone stock bike, it doesn't give you any marked improvements unless you spend the time tuning it on a dyno, and even then, the difference is really only marginal...
So if you really want a cleanable and re-usable filter, and have the time and money to properly tune it, it's an option... If not, go with an OEM filter, the chance of success is much higher...
A caveat here... On a fully worked over engine, you get improvements, but make compromises in everyday driveability, as far as mileage and smoothness... I tried it, but didn't like it...
The K&N improves airflow, yes... But the VTR is a finicky beast, and just increasing air with no other changes usually only decreases mileage... Some have managed to tune their bone stock bikes with a K&N to their satisfaction, usually with a lot of time spent... Some have just slapped it in there and called it good... Some of us have spent time and money trying the K&N and given up on it...
The closest you will get to a consensus around here is probably that on a bone stock bike, it doesn't give you any marked improvements unless you spend the time tuning it on a dyno, and even then, the difference is really only marginal...
So if you really want a cleanable and re-usable filter, and have the time and money to properly tune it, it's an option... If not, go with an OEM filter, the chance of success is much higher...
A caveat here... On a fully worked over engine, you get improvements, but make compromises in everyday driveability, as far as mileage and smoothness... I tried it, but didn't like it...
05-16-2013, 05:51 AM
#13
Junior Member
Squid
Join Date: May 2013
Location: Scotland
Posts: 2
Intro & Oops
Greetings fellow Stormers,
I've just joined the forum.
I just bought and installed a K&N air filter for my '98 Firestorm. Rather wishing I'd read here first...
After the ride from Scotland to Morocco and back last year the old OEM filter was full of dust and crud, so I thought I'd treat the beastie to a washable air filter.
Took her for a test ride yesterday - running hot and lean, backfiring and lacking power. I had no idea that a wee air filter could make that much difference.
I'm about to pull the carbs and give them a good clean and re-sync, but from reading a few threads it sounds like re-jetting the carbs to work with the K&N might be a long and ultimately not very rewarding process.
So, having just spent money on a K&N, what am I to do? Put it on the shelf and go spend more money on an OEM? Seems like a waste. Is there anything that can be done to make these work? I'm not looking for more power - the VTR has more than I can use - plenty for touring and pulling up and down mountains. I just want her to run as well as possible.
Thoughts?
I've just joined the forum.
I just bought and installed a K&N air filter for my '98 Firestorm. Rather wishing I'd read here first...
After the ride from Scotland to Morocco and back last year the old OEM filter was full of dust and crud, so I thought I'd treat the beastie to a washable air filter.
Took her for a test ride yesterday - running hot and lean, backfiring and lacking power. I had no idea that a wee air filter could make that much difference.
I'm about to pull the carbs and give them a good clean and re-sync, but from reading a few threads it sounds like re-jetting the carbs to work with the K&N might be a long and ultimately not very rewarding process.
So, having just spent money on a K&N, what am I to do? Put it on the shelf and go spend more money on an OEM? Seems like a waste. Is there anything that can be done to make these work? I'm not looking for more power - the VTR has more than I can use - plenty for touring and pulling up and down mountains. I just want her to run as well as possible.
Thoughts?
05-16-2013, 06:23 AM
#14
Administrator
MotoGP
Join Date: Apr 2006
Location: Kempner, TX
Posts: 4,402
So, having just spent money on a K&N, what am I to do? Put it on the shelf and go spend more money on an OEM? Seems like a waste. Is there anything that can be done to make these work? I'm not looking for more power - the VTR has more than I can use - plenty for touring and pulling up and down mountains. I just want her to run as well as possible.
Thoughts?
No Dyno? Then many hours of trial and error, and you will need a great understanding of HOW the carburetor systems work in general and specifically on a VTR as well as versed in what the felt symptoms are of a lean stumble, rich stumble, flame out, surge, hiccup ........
05-16-2013, 08:38 AM
#15
Senior Member
Superstock
Join Date: May 2012
Location: UK
Posts: 397
So, having just spent money on a K&N, what am I to do? Put it on the shelf and go spend more money on an OEM?
(:-})
05-16-2013, 08:59 AM
#16
Senior Member
MotoGP
Join Date: Jul 2010
Location: Phoenix, AZ
Posts: 3,869
So, having just spent money on a K&N, what am I to do? Put it on the shelf and go spend more money on an OEM? Seems like a waste. Is there anything that can be done to make these work? I'm not looking for more power - the VTR has more than I can use - plenty for touring and pulling up and down mountains. I just want her to run as well as possible.
Thoughts?
Thoughts?
Here are a couple of notes. It seems to help to somehow add the air dam on the front of the filter that the stock one has molded in. Others have tried this and have decent feedback on it. It has something to do with calming down the turbulence from what I remember. A piece of plastic glued on or something.
One other thing I have considered is getting some other thin filter element and attaching it onto the K&N to make a kind of filter layer cake effect. A couple of people on here have experimented with completely hacking the paper element of the stock one and throwing some kind of HVAC filter on there.
I'm not necessarily condoning these as I have not tried them, but they could get you started on ideas...
05-16-2013, 06:32 PM
#19
Senior Member
Superstock
Join Date: Apr 2013
Location: SF Bay Area
Posts: 466
As stated before I am new to the SH and to sportbikes in general, but in the short experience I have with the bike I haven't noticed a difference between the OEM and KN filter. Changing from an OEM to a KN the PO gave with the bike, there was no "popping" on deceleration or a change in revs etc. He said it was re-jetted, and it has staintunes, but from what I read here that wouldn't "compensate" (for lack of a better word) for the extra flow of the KN. Is there any extra mods I should look for to cause this lack of change? Thanks for dealing with the inexperienced.
05-16-2013, 06:53 PM
#21
Senior Member
Superstock
Join Date: Apr 2013
Location: SF Bay Area
Posts: 466
That could be very true, making it run 'poorly' with both the OEM and KN, which for me is fine. It has more power than I need or care to explore at the moment. Lets just say that I have great respect for the throttle and do not plan to find its limits any time soon.
06-06-2013, 08:56 AM
#23
Senior Member
Back Marker
Join Date: May 2013
Posts: 134
New here as well and wish I would have read this before buying the KN I just put in as well. Just got the bike and after going through it the filter looked to be factory so I wanted a new one and figured I would pop in the KN so that it was washable. Havn't had a chance to ride it yet since putting it in as it won't stop raining. Guess time will tell.
07-08-2013, 07:13 PM
#24
mad skill collector
Squid
Join Date: Oct 2009
Location: Hayward, San Francisco bay area: California
Posts: 77
Oh I know I am gonna regret this , I have a new K&N and can tell you what to do to make it work correctly. The mod I tried with good results was to cut a plastic dam that fits in the groove where the stock filter fits.
The K&N filter is missing this dam and I believe that is the reason for all the trouble with them. The airflow with the stock filter is different due to this dam ( air must pass over and then down) where the K&N air passes across the face and creates a bad resonant turbulence that results in a 3-4k rpm stumble. Filters are only different in that aspect as far as I can tell so let me know if you want to try it and I'll send it for the cost of shipping and two iridium plugs.
The K&N filter is missing this dam and I believe that is the reason for all the trouble with them. The airflow with the stock filter is different due to this dam ( air must pass over and then down) where the K&N air passes across the face and creates a bad resonant turbulence that results in a 3-4k rpm stumble. Filters are only different in that aspect as far as I can tell so let me know if you want to try it and I'll send it for the cost of shipping and two iridium plugs.
07-08-2013, 08:03 PM
#25
Rex Kramer-Thrill Seeker
SuperBike
Join Date: Jan 2011
Location: Brookfield, WI
Posts: 2,312
Since never seeing a stock airfilter before and my bike having came with what looks like some cobled together K&N filter, with a metal ring and rivits, can anybody post pictures of a proper K&N filter and also a stock air filter?
07-08-2013, 08:35 PM
#26
Senior Member
SuperSport
Join Date: Apr 2013
Posts: 972
Oh I know I am gonna regret this , I have a new K&N and can tell you what to do to make it work correctly. The mod I tried with good results was to cut a plastic dam that fits in the groove where the stock filter fits.
The K&N filter is missing this dam and I believe that is the reason for all the trouble with them. The airflow with the stock filter is different due to this dam ( air must pass over and then down) where the K&N air passes across the face and creates a bad resonant turbulence that results in a 3-4k rpm stumble. Filters are only different in that aspect as far as I can tell so let me know if you want to try it and I'll send it for the cost of shipping and two iridium plugs.
The K&N filter is missing this dam and I believe that is the reason for all the trouble with them. The airflow with the stock filter is different due to this dam ( air must pass over and then down) where the K&N air passes across the face and creates a bad resonant turbulence that results in a 3-4k rpm stumble. Filters are only different in that aspect as far as I can tell so let me know if you want to try it and I'll send it for the cost of shipping and two iridium plugs.
07-08-2013, 08:42 PM
#27
Old and dangerous
SuperSport
SuperSport
Join Date: Jan 2012
Location: DFW Texas
Posts: 604
07-09-2013, 02:33 AM
#29
Senior Member
Superstock
Join Date: May 2012
Location: UK
Posts: 397
The K&N filter is missing this dam and I believe that is the reason for all the trouble with them.....
I'm not saying your wrong and I like your way of thinking. Think outside the box so to speak LOL But this does need some evidence to back it up. Don't forget that lots of people have spent some time playing around with K&N's and experimenting with various changes to make it work, whether that be with the filter itself or with jetting.
Some peole have had good results with a K&N but I believe some considerable time has been taken on the dyno to get it running smooth throughout the rev range in all gears. Personally I played around for nearly a year but was never quite happy with it, would always get a flat spot somewhere that I just could not quite get rid off. I could move the spot around, but not get rid totally. I ended up going back to a BMC and went. Go figure.
I have had good experiences with a K&N in the past with other bikes but for some reason not the VTR no.(:-})
07-09-2013, 04:27 PM
#30
mad skill collector
Squid
Join Date: Oct 2009
Location: Hayward, San Francisco bay area: California
Posts: 77
The Info I gave was from my observations only , someone may not have made that observation. I am sure glad the creationists on here chimmed in to add their take on all this . now back to our regularly scheduled dead horse beating...(what tires/oil/color/jets should I buy?) lmao
RSRO...
RSRO...
