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Snatch is cured ! DNA Air filter


Two questions
will it "cure" the snatch with a std exhaust
and has anyone worked out that it's not damaging their engine by running too lean?
 
I dont't know what to believe. My dealer told me in no uncertain terms to run my Akra without the baffle in would need the ECU flashed. Let alone with a filter too.
 
Peachy00 said:
I dont't know what to believe. My dealer told me in no uncertain terms to run my Akra without the baffle in would need the ECU flashed. Let alone with a filter too.
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I was under the impression that a free flowing exhaust creates less pressure in the cylinder which allows the burned up gases to escape quicker which in turn means that its sucking more fresh air and fuel in which means the mixture is different than it was intended from the factory (as they allow for some unburned gasses to still be in there), which makes it run lean and to put this right you need to adjust the fuelling to compensate via an ECU map or fuel controller etc.

As for an aftermarket air filter I think that same will apply, more fresh air in the system could make it run leaner.
 
I don't know about the technicalities but my engine seems fine, performance is excellent and have much smoother throttle control...no unusual sounds or blips....I'm happy!
 
rob5006 said:
I don't know about the technicalities but my engine seems fine, performance is excellent and have much smoother throttle control...no unusual sounds or blips....I'm happy!
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I know I'm running my Akra with the DB killer removed and the bike "feels" fine. I do have a bit of lurching while holding a constant throttle but I get that with the DB killer in also so I don't think thats related (hopefully my fuel controller will smooth that out) Only a dyno or A/F gauge will show how the mixture is really running. From the average Joe's point of view I don't think running an open pipe or filter will do any harm.

I'll deffo be getting a filter at some point also.
 
Little bit on info here on standard bikes running lean FAQ EFI Controller

From various sources online it seems the MT/FZ's throttle roll on is jerky because the mixture at the first part of roll on (along with a lot of other parts of the rev range) has been leaned out by the factory to help meet emissions requirements so to cure it you need to richen the mixture, which is what happens when you fit a PCV or EJK or have an ECU flash etc that's why I'm baffled as to how fitting an air filter (which should technically lean it out even more) is curing the jerkyness.

For any more info search "EJK" on the FZ-09 forums and usually you'll see a lot of info on where the bikes are running lean and with what mods etc.
 
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Confusing isn't it?

I emailed the UK supplier BR Tuning (link in a post above)

Thanks for your enquiry.

We would recommend you get the fuelling checked after installing the filter but judging by the number we sell and not had 1 single adverse comment, I doubt there will be an issue.

We have recently sold some to a Yamaha main dealer who claimed they the improved the overall running noticeably.


So a dealer is saying the bike runs better with one - The mystery deepens.
All I want to see is a dyno report saying its ok with a std exhaust and I'm getting one!
 
Locksmith said:
Confusing isn't it?

I emailed the UK supplier BR Tuning (link in a post above)

Thanks for your enquiry.

We would recommend you get the fuelling checked after installing the filter but judging by the number we sell and not had 1 single adverse comment, I doubt there will be an issue.

We have recently sold some to a Yamaha main dealer who claimed they the improved the overall running noticeably.


So a dealer is saying the bike runs better with one - The mystery deepens.
All I want to see is a dyno report saying its ok with a std exhaust and I'm getting one!
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Yeah it is confusing, by logic the only way the filter would cure the jerk would be because its restricting airflow making the mixture rich! But I don't believe an aftermarket filter would restrict air flow.
 
The air filter INCREASES the air flow by 29%. Just wandering if its diluting the fuel with air slightly but enough to soften the throttle...off to Scotland tomorrow for a good lengthy run but have already blasted about on all modes with the air filter so expecting nothing more than its recent run of improved performance.....anyway, I didn't want to get into all this due to not having the aquired level of knowledge to give a thorough opinion....over to you chaps. Will enjoy reading your results and findings. Good luck!
 
rob5006 said:
The air filter INCREASES the air flow by 29%. Just wandering if its diluting the fuel with air slightly but enough to soften the throttle...off to Scotland tomorrow for a good lengthy run but have already blasted about on all modes with the air filter so expecting nothing more than its recent run of improved performance.....anyway, I didn't want to get into all this due to not having the aquired level of knowledge to give a thorough opinion....over to you chaps. Will enjoy reading your results and findings. Good luck!
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If it works then roll with it, thats what its all about at the end of the day.

I do find it odd however that Yamaha will put the Akra on your bike for you with no mention of fueling or an ecu flash to match it.
 
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Dna it sounds like you are behind this. It is just to clear. If you want your product to sell also sell ecu updates this whole thread is just bullocks. Sorry to bust your balls sales person but leaning out even more is just complete bs.
 
guidow said:
Dna it sounds like you are behind this. It is just to clear. If you want your product to sell also sell ecu updates this whole thread is just bullocks. Sorry to bust your balls sales person but leaning out even more is just complete bs.
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How can it be BS if several people in this thread have tried it and have had it work? The only logical explanation I can come up with is that somehow pairing up an open pipe and a free flowing filter has got the mixture right.

As I said above usually adding one of the above would cause lean running so I dunno. If it is working then I bet it doesn't have to be a DNA branded filter, I bet any aftermarket filter would work.
 
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