@ Chris Canning re Airbox

[Bixxer Bob]

Moved over from Kenny's thread...

Here's a poser for you Chris; I've been thinking this around and am in danger of my head exploding.

The benefits of taking out the baffle and putting in a K&N are undisputed - you and several others are running it with better performance and no ill effects.  But I can't get my head around why it works.

The ECU relies on the airbox pressure and the throttle position to work out how hard the engine is working.  If  there is a depression in the airbox and the throttle is wide open it's working hard, so it switches to AF2 map which is pretty much 13 to 1 across the range for max power.  So here's the head-scratcher, with the baffle out and K&N, the pressure in the airbox will be higher no matter what the throttle position because the free flow of the airbox and filter means the throttle bodies sucking produce less of a depression.  So if the ECU thinks the engine is working less hard for a given throttle position it'll not switch maps, and it'll use the lower part of the AF 1 map which is quite a weak mix anyway.  

What it should do, I think, is give you better fuel consumption at light throttle to medium throttle loads and switches to AF2 above a certain throttle opening regardless of pressure so you still get the power on full throttle.  :icon_scratch

[Chris Canning]

I'll digress for a mo if thats ok,before the Tiger Triple and the RAT site all info on Tigers came via the two Yahoo sites,I still owe a gent a very large drink from Arkansas when he put me onto the yellow box converter!!.

There was a posting put on the Yahoo site which was translated from a Dutch bike magazine about the mod,the difference being that actually ran a test between two bikes one with the mod and one without.

As it was posted.

Trying to understand why Triumph severly chokes the Tiger in stock form could be seen as an attempt to create a higher suction of air through the airbox thus increasing the low end torque,but the Tiger with airbox mod was stronger in low end torque than the Tiger without the mod,my belief is the increased volume of the imeadiatly available air makes for a stronger initial throttle response.
As as a side note even with the snorkel removed the air entrance is notably small,attempting to modify the opeing to a larger diameter should accompany the use of a exhaust gas analyser to assure an over lean condition doesn't develope.
The closed loop of the 955i EFI maybe smart enough to account for greater air intake of a larger opening,but exhaust analysis would be needed to verify this.

By comparison the Tiger with the blanking plate taken out was way better,BUT!!!! this was 2003,I had one or two conversations with various folks who seemd tto beleave it would run ok,so I did it  :shock: ,there's a marked step in power at 6 thou to point were as I wasn't sure I liked it as it unsettled the bike,but with a 19t sprocket even I don't need to venture much above that in the UK.

Now all of this was still hear say,what was going to happen after a long run on a motorway  :? ,a flat out run from Milan to Genoa and a 1000 mile day sorted the doubts out and I've used like that ever since,so whats that?? 7/8 years.

My blanking plate I took out with a dremmel!! what a mess,the second I did took it out with a soldering iron,more smell less mess  :D

[Bixxer Bob]

Aye, as I said Chris, I don't doubt the it works, just don't understand why.

Anyone from Triumph that reads these threads and knows what really goes on must chuckle to themselves as we pontificate and theorise on the inner workings :lol:

[Chris Canning]

Aye, as I said Chris, I don't doubt the it works, just don't understand why.

Anyone from Triumph that reads these threads and knows what really goes on must chuckle to themselves as we pontificate and theorise on the inner workings :lol:

Hence why most of my efforts have been brakes/wheels/suspension,I've a racing background,tinkering with the former can be a lot less dire than tweaking a fuel map  :D

I bought a secondhand airbox incase it didn't work,just like the secondhand speedo cable in case the Yellow Box converter didn't  :oops:

[ChazzyB]

I agree with Chris' assertion about the step in power at 6K-ish. I thought my clutch must be slipping, the way the revs suddenly pick up. OTOH, it could be 'cos the power's down below that point...

I wondered if the baffle out was the reason for my high-altitude misfire in the Alps, but that doesn't seem to stack up either.

[jwray76]

can we get a little more info on exactly what you guys are cutting out?

Also what tunes and exhaust are you running with this airbox mod?

[ChazzyB]

can we get a little more info on exactly what you guys are cutting out?

Also what tunes and exhaust are you running with this airbox mod?

See here:

http://www.triumphrat.net/tiger-mods-an ... x-mod.html

TOR pipe and tune 10121. I suspect 'Winger' may be Chris Canning.

[Chris Canning]

TOR pipe and tune 10121. I suspect 'Winger' may be Chris Canning.

And away from the net have to answer to either,well Wing actually  :roll: ,it's a long story

[Chris Canning]

The big thing in all of this,with above your Tiger will pull a 19t sprocket exactly the same as a stock bike pulls an 18.

Hence why on the NW200 posting I was on about the guys with 1050's who were shocked at the way it went,there's me thinking their going to blow by me any minute,and in reality their hanging on for grim death!!

[Bixxer Bob]

What I'd give for a look at the logic coded into the ECU  :roll:

[Chris Canning]

When this tune thing started,seemed like a great idea,I'd have a new tune installed ride off round the corner,felt totally different so it must be good  :roll: ,what I learned,the problem is either moved else were or you swap one problem for another,just a merry go round.

You want to transform your Tiger put an aftermarket shock on,you'll not be too bothered about the map  :D

[Timbox2]

You want to transform your Tiger put an aftermarket shock on,you'll not be too bothered about the map  :D

Oh, yes, I concur :D

[Bixxer Bob]

One would expect to buy a bike and go ride it, or if it's sick take it to the dealer to fix, but this is Triumph's early attempts at FI (and we all know about the TT600).  Self learning seems to be the way forward.  Now if I was lucky enough to have a dyno at my disposal, and the Triumph guide to how it all works (and I don't mean the workshop manual, I mean the coder's notes), I'd be able to get on top of this pretty quickly, but since I haven't, it's trial and error and theorising, and filtering out the tons of crap that's written about it (some of it by me I'll admit, but it's all in good faith and the best knowledge I have at the time) to find the gold.

Having said that, I did come across some interesting info a few days ago that I'll be working on as soon as I can, although it looks like we'll finally be moving house around 21st, so it won't be imminent.  If it's good gen, and it works, I'll post it up and we can forget custom maps as they should all run properly on a stock tune.

[lucifer]

One would expect to buy a bike and go ride it, or if it's sick take it to the dealer to fix, but this is Triumph's early attempts at FI (and we all know about the TT600).  Self learning seems to be the way forward.  Now if I was lucky enough to have a dyno at my disposal, and the Triumph guide to how it all works (and I don't mean the workshop manual, I mean the coder's notes), I'd be able to get on top of this pretty quickly, but since I haven't, it's trial and error and theorising, and filtering out the tons of crap that's written about it (some of it by me I'll admit, but it's all in good faith and the best knowledge I have at the time) to find the gold.

Having said that, I did come across some interesting info a few days ago that I'll be working on as soon as I can, although it looks like we'll finally be moving house around 21st, so it won't be imminent.  If it's good gen, and it works, I'll post it up and we can forget custom maps as they should all run properly on a stock tune.

Oh please tell us more!!!

[Bixxer Bob]

Not yet, I don't want to post anything until I know it at least works for me - like the current map and settings I'm using! :lol: