Air filter mod?

[sirch345]

so have we a defined answer on this mod chaps ? ya or na !!!!!

I like it. I think the thing to do is try it for yourself. Either way it doesn't seem it's going to make a massive difference going by the replies.

Thanks to all for your input


Chris.

[Griff1977]

Ive just put K & N in, not risen yet but am nervous how it will run/ride? Ive kept the old filter so I can change back, but hopefully not need to. Haven't got the funds to go tweaking! Griff

[sirch345]

Ive just put K & N in, not risen yet but am nervous how it will run/ride? Ive kept the old filter so I can change back, but hopefully not need to. Haven't got the funds to go tweaking! Griff

Not wishing to dampen your hopes, but if the jetting is standard I'll be suprised if you don't have a flat spot in one area. Do let us know how it goes,

Chris.

[AMCQ46]

Ive just put K & N in, not risen yet but am nervous how it will run/ride? Ive kept the old filter so I can change back, but hopefully not need to. Haven't got the funds to go tweaking! Griff

Not wishing to dampen your hopes, but if the jetting is standard I'll be suprised if you don't have a flat spot in one area. Do let us know how it goes,

Chris.

I would say the same, the K&N when run with race cans will need some jet changes, give it a try and if it feels bad put the stock one back in and get it dynoed with the new K&N and rejetted.

[sirch345]

Well mine has now been modified. While I was going through this procedure I did wonder about cutting out the side pieces as well, as in the marked red bits in the photo below. I wasn't sure if this would be a good idea or not, so I've left them there for the time being.

All I need now is for summer to arrive so I can try the bike out.



Chris.

[VTRDark]

All I need now is for summer to arrive so I can try the bike out.

Good luck with that one.

Keep us informed to any difference you may or may not feel with the mod. I have a feeling that with an aftermarket filter there is not much difference, but with a standard filter there may be some improvement. With the likes of a K&N the main filter sits more flush with the surrounding plastic of the filter. The originals have a lot more depth to them. So this mod may allow more of a free flow airflow.

(:-})

[sirch345]

Cheers Carl Today was good weather-wise, but I had other commitments. Hopefully I can get out soon, then I'll report back

Chris.

[sirch345]

At last I managed to get out this morning, even then after kitting up and getting the bike outside the garage it started to rain, but I decided, hard luck I'm going out now anyway. As it turned out it didn't stay wet for very long so not so bad.

I was trying to keep an open mind on this mod, rather than expecting it to make a difference when actually it may not, if you get what I mean.

This is my opinion, I can't really say this air filter mod has made a lot of difference, however it does feel it has lowered the torque curve a little, and appears to have smoothed out the fueling a small amount as well, as in slightly smoother running and in pick-up as you accelerate. Apart from that I think the only way you could tell 100% what difference it has, or has not made would be a before and after dyno run. So there you have it,

Chris.

[VTRDark]

Sounds like it's been beneficial for you then apart from the torque but like you say, only a dyno run really tells you exactly what's going on.

The rain also got me today. I was working on my carbs, there was a downpour so I packed up and got my tools and things inside and then the sun came out. Crazy weather.

(:-})

[sirch345]

Sounds like it's been beneficial for you then apart from the torque but like you say, only a dyno run really tells you exactly what's going on.

The rain also got me today. I was working on my carbs, there was a downpour so I packed up and got my tools and things inside and then the sun came out. Crazy weather.

(:-})

That's the same things as me, I got back home (didn't do more than 25 or 30 miles) as it looked like it was going to rain again. Put the bike away and about 1/2hr later the sun came back.

May be I didn't explain that bit about the torque curve as good as I could have What I mean is, I felt the torque came in slightly lower down in the rev range than it did before the air filter mod was done. As in if you fit two long carb trumpets, stacks or bell mouths or whatever you like to call them the torque comes in earlier. So that bit was good, not bad.

Chris.

[scubadog]

Thought I'd correct the "burnie morgan airfilter modication" advice a little... At the foot of his page he says removing the snorkel doesn't work on a Firestorm. 100% WRONG. He also says cutting (or,as he says, "drilling") holes in the airbox top cover doesn't work. 100% WRONG.

I've made both mods to my naked Firestorm streetfighter - they absolutely DO work and, in fact, I had to do them to get my unfaired bike running correctly!

I found out the airbox on a Storm needs still air to work efficiently and, without the fairings, the snorkel was taking in too much moving air. I removed the snorkel and plastic welded a piece over the aperture to seal it off. Then cut two circular holes in the sloping rear face of the airbox top. I also had to remove the foam on the underside of the tank and add a small spacer to the front tank mount to allow airflow.

All this took place over a couple of months while I was struggling to get the fueling right after the streetfighter build was finished. Admittedly it took a few visits to my local dyno bloke and more than a few head scratching sessions. I also trial-and-errored a couple of other airbox lids before I got the right hole sizes in the right positions. BUT, both mods work.

All that because I took the damned fairings off!!

Scoob

[VTRDark]

the snorkel doesn't work on a Firestorm. 100% WRONG

Funnily enough I have just been reading about this on the Oz forum. Apparently removing the snorkel richens things up, so requiring smaller than standard main jets. Logically you would think removing it would lean it out.

How did you find the jetting by making holes. Can you confirm it requires smaller mains?

http://ozfirestorm.proboards.com/index. ... read=11862

(:-})

[lloydie]

Last time I put mine on the dyno we removed the snorkel to see what would happen and yes it ran very rich .
It wouldn't even pull past 5k .

[tony.mon]

Got me thinking now....
After my last bout of airbox mods it is a lot better in the low and mid ranges, but misfires a little if the throttle is whacked open above 7K.
If you feed the throttle on steadily it'll pull hard and hit the limiter.

But I'm wondering if it could do with smaller mains..... seems like running too rich on the main jets, but until I dyno it I can't tell for sure.

A plug chop will only tell you what's been going on at the time you killed the ignition, and is less effective at 5K+ than below.

Might just be that the snorkel mods have made it too rich on the mains.

If so; this is good news... I can change to smaller mains and get better fuel economy.

I've already noticed that it is getting better than usual economy, mind you, that's on Super 98 RON fuel, so it's relative at best.
Got to 177KM tonight before the orange fuel light came on. 109 miles, so not too bad.

And I haven't been hanging about.
As ever.

[VTRDark]

The guy on the Oz site does say he could never get it to work with the K&N though. You have a K&N in yours Don't you Tony. Maybe a filter change could be a good idea, might simplify getting it dialled in.

The bloke seems to know what he's talking about and works with turbo induction systems.

(:-})