Of course the system is engineered to meet emissions standards across the globe, it is also engineered to provide the most amount of air-flow while keeping noise levels down. Have you ever ridden a bike with pod filters? It sounds like a Dyson between your legs.

That being said, the more air and fuel you can get into an engine and the more exhaust you can get out, the more power you tend to make. In the case of the Triumph Twins you're also battling a restrictive ECU map. You could modify all the bolt-on yadda-yadda you want, but when it comes down to it you won't get much (if any) benefit without a reflash.

I suggest buying the $18 SAI removal kit, as well as plugging off the O2 sensors, downloading the TUNEECU app on your phone, buying an OBDII-USB cable (and an adapter to go from USB 2.0 to Mini USB or whatever your phone uses)... then download a few maps from the TuneECU website.

You can then shut off the SAI and O2 sensors within the map settings, change your redline, adjust your speedo error, and flash a map whenever you want...

As far as JUST the airbox, if you modify any part of it (remove the snorkel, change the cover, remove the baffle, install a hi-flow filter) you will run the risk of running lean, especially with the Arrow 2-2 installed.

There are specific maps for airbox mods and Arrow 2-2 based on the Arrow 2-2 map (a close version of the TOR map) that will make the bike run a lot better.

 

Airbox removal is supposed to help add some power to the bike, and also makes it louder for ppl who like a brutish sounding machine. Personally I think it's just a lot of work for a power gain I probably would not be capable of noticing or exploiting. I also like a little thrum to my Scrambler but am not big on the deafening roaring machines... I think the removal happens a lot bc a) a certain segment of the riding community likes LOUD bikes b) a certain segment wants power power power and c) it is a relatively straight-forward mod that makes you feel cool for being able to do it.

I recently completed changing my Scrambler OEM exhaust to an Arrow 2-in-1, removed the SAI and O2, and changed to a Breathe kit to ditch the OEM airfilter snorkel along with it. Chose to keep the airbox (see: above lol). Did it all by getting a kit from Triumph Twin Power, which included everything I needed (including tune for my chosen set-up and OBD cable etc). Honestly totally worth the money. I can see why ppl who are really mechanically well-versed would see it as expensive for a bunch of stuff they can put together themselves, but I'm learning as I go. You choose your kit based on a set of options, and it all arrives labelled and with full instructions.

Plus you get a tune to adapt to the changes. I gather if you are removing the O2 sensors, you should tune regardless of whether the sensors have been cut free of the bike or not, since the OEM exhaust mapping relies on input from the sensors. If your bike is still running its stock tune with that Arrow exhaust, you doubly should re-tune. I was extremely leery of messing with the ECU on my Scrambler (the nearest Triumph dealer is 2 hrs away from me when I screw things up), but the TTP tune install was super easy and took maybe 30 mins once I was sure I knew what I was doing.

At the very least, check out the available kits for your bike. The instructions are all on the website so it's a good resource to understand the modifications if you choose to make them. Personally found the kit really worth the money - it's not just about the parts, but also about getting the expertise of someone who knows far far more.

 

To grossly oversimplify, for a small gain in top end power, you'll lose a good bit of low and mid-range torque. In other words, you'll likely lose a good bit of usable "power". Lots of info on this site if you do a deep search.

 

The cool kids all seem to yank out the airbox, add filters, rip apart a lot of stuff and modify the bike............

.............then post pleas for "HELP!" with their jetting issues, electrical issues, no-start issues, etc, etc.
Always makes for amusing reads!

Rex

 

Aye. Messing with the fueling and stuff is like opening Pandora's Box.

If and I do say if you get it right the gains are minimal and really not worth the trouble.

The only thing guaranteed is it will empty your wallet.

Im sure some will come on here and tell stories if it being easy peasy and massive gains and no problems, but they will be mostly full of crap, sorry but that is the truth of the matter.

 

Like Grimaulkin, I went through Mike at Triumph Twin Power. Super helpful for someone like me, who didn't have a clue what he was doing. Terrified of messing with the tune, but it wasn't bad at all. That allows you to remove the O2 sensors and SAI. Kept the airbox, but removed the baffle. If I could do it again, I might not even bother taking out the baffle. Was a pain in the ass, and I often wonder if I got the box back together properly with enough silicone to seal it.

But it's running great for two years, hence. And the sense of accomplishment is worth something

 

Have done it both ways for people and on bikes I have owned. I think the only benefit to the airbox removal is looks...but even then, I do not think it is clean enough of a look to merit that. If you were to do the pods then continue to rewire and clean up under the seat then put a little antigravity battery bolted to the underside of the seat, then it would clean it up, but that is a lot of work.
There was a comparison somewhere years ago that the performance gains were less than 2 Hp different between removal with the other mods and keeping it, and just using a belmouth.
Other mods meaning 02 sensors, SAI delete, baffle removal, and the tune from TTP with tuneecu.
The airbox removal way is also more expensive. I think from memory the belmouth way is like 100 bucks a HP when its said and done, and airbox something higher than that, I really don't feel like researching cost and doing math to refresh my memory.

 

I also just removed the baffle by reaching in and snapping it with a big pair of channel locks.

 

I'm a cool kid that removed his air box. Had fun doing it. Had fun learning about the jetting. Enjoy the extra power it brought (in conjunction with different pipes, and the jetting thing). Enjoy the sound.

Some folks enjoy tinkering. Some don't. Neither are wrong.

YMMV. There is no need to do such things if one doesn't want to. The bikes are a lot of fine stock as well.

 

People who removed their air boxes are dumb.

People who didn't remove their air boxes are dumb.

People who do things differently than me are dumb.

It is good to feel smarter than other people.

Hail the internet.

 

MY Bike 2012 EFI thruxton, now runs with Arrow 2-02 exhausts and factory remap.

Comments and suggestions are appreciated.
Steve

Removing the airbox is more a carb-bike thing than EFI. I think it was @Ventura who did a lot of work when the EFI came out. I think removing the baffle and opening both sides ended up being the sweet spot for EFI tinkerers.

My wife has a stock EFI Bonnie, I'm not allowed to mess with it. Airbox and baffle in place, stock pipes, etc. I always find myself going faster on her bike than I do on mine. I think it's because it's quieter, and without the audial feedback I just keep screwing on the throttle. It's a fun bike, other than being so damn quiet

 

Steve, have a read HERE and it should answer your question. Basically airbox mods are about mid range torque and airbox removal is about top end power.

 

Hey Mike, great to see you are still heavily involved. Hope all is well with you. Do you still do igniter remaps for the carb'd bikes? That's one thing I never got around to - should probably go the whole hog.

 

Wow! An airbox removal justification thread. Complete with all the vehemence of the people who have done none of it and all of it. Brilliant, takes me back to the old days before the EFI bikes came on the scene. Ah - happy days.

Just to set a few of you straight though, the cool kids are out riding their bikes, having fun and waving at each other, then meeting at cafes and admiring each others bikes no matter what they have or haven't done.

Anyone who doesn't agree with me is full of crap, and certainly doesn't have a packet of crush washers with 4 in it. Which is the only way to add more power to your bike anyway. Forchetto said so.

 

Wow! An airbox removal justification thread. Complete with all the vehemence of the people who have done none of it and all of it. Brilliant, takes me back to the old days before the EFI bikes came on the scene. Ah - happy days.
Just to set a few of you straight though, the cool kids are out riding their bikes, having fun and waving at each other, then meeting at cafes and admiring each others bikes no matter what they have or haven't done.
Anyone who doesn't agree with me is full of crap, and certainly doesn't have a packet of crush washers with 4 in it. Which is the only way to add more power to your bike anyway. Forchetto said so.

Excellent Prop!! :smile2:

I just happened to breeze in here after a long time away and lo and behold, an airbox thread!! :grin2:

Good to see the subject still gets lots of attention and the should I / shouldn't I debate continues.

Long may it remain so!!

PS... Ive still got my air-box-less Scrambler with flat-slide carbs
No turning back for me!! :grin2:

 

I will put this out there.

Who has gone through the exercise and had the bike running bang on to the optimum performance without having to revisit the fueling?

I guess my thoughts come from my 2006 Speedmaster where I went through the exercise of doing carb and airbox removal changes.
In the end I booked a Dynotune session and after 4 runs we got it to its best.

At the end of the day well... the roar from the pod filters was not something I was expecting, the airbox also is a muffler.
Didn't mind the free flow mufflers but the roar from under thank was something else.

At the end of the day it used a lot more fuel with minimal HP gains and cost a lot $ to get it sorted.

I would really like to hear from a member who has gone through the exercise and had the bike running bang on to the optimum performance without having to revisit the fueling?

Meantime just give that Kiwi a good kicking for being honest and telling it like it is.

 

I guess my thoughts come from my 2006 Speedmaster ... the airbox also is a muffler.
Didn't mind the free flow mufflers but the roar from under thank was something else.

That must be something specific to the Speedmaster design. On the Bonnie/Thrux/Scramb you get a little tone difference, and a bit of a cool induction sound when you get on the throttle heavy. But I don't think anyone on that platform would think the sans-airbox sound is a "roar". Nothing remotely close to the roar of open pipes.

 

I took the easy option after looking at the dyno comparisons at the Triumph Twin Power site and used their tunes, I have a carb bike with breathe intake and no airbox baffle with 2 into 1 running a TTP tune, jet kit and igniter, runs awesome, also a paif of EFI bikes, one withe TTP stage 2 no airbox just the largest DNA pod air filters that will fit and its runs really well, no issues with intake roar at all, the other EFI bike has airbox with DNA filter and Breathe intake, these bikes all run so good that whichever one I ride seems the best at the time, like others have said, read the tech articles at Triumph Twin Power and pick the combo you like, they are all good options, have an airbox or don't have one, we are lucky enough to be able to have it either way on these bikes.

Sent from my SM-T310 using Tapatalk

 

Well I did it on my '02 Bonnie and hate everyone who hasn't! Actually, it cost me roughly the morning, and maybe 40 bucks total, 2 Uni pod filters and a set of 145MJ's.

I haven't found any loss/changes in torque in the lower ranges, but the top end has increased dramatically. I still have lots of throttle left after the ton, and regarding noise, none is heard nor is noticeable really until the throttle is blipped or rolled on quickly and held.

Easy and fun job really, no regrets, haven't had it dyno-ed yet but mileage is holding at 44-46mpg just as pre-chop and the idle/starting is smooth as silk.

 

Well I did it on my '02 Bonnie and hate everyone who hasn't!

Me too! Down with nasty airboxes!

Actually after I took my airbox off, I won a million billion dollars in the lottery. Coincidence? I don't think so.

 

I cant recommend this...I removed the airbox and now my pants are too small and I walk funny :gah

 

I just went out and took my airbox off the shelf in my shed, and put it to my ear,

It roars like the sea.

So I think that means that I need to put sea foam in the gas to make it run right.

 

Personally I didn't remove the airbox + sai myself, but fixed the super lean condition as previous owner had just removed the airbox + done bafflectomy without any changes to stock jetting. Also tons of other crap like dodgy wiring and such. But anyho I swapped the horrendous bafflectomied stock pipes for some aftermarket pipes that flowed even better without braking my ears and neighbours windows. With little tinkering with jets the bike runs absolutely fabulously.

I think this whole thing boils down to wether or not you want/like to tinker with your bike like I do. If you plan to change exhaust, etc, you need to change the mapping or jetting (in carb version).

 

I think this whole thing boils down to wether or not you want/like to tinker with your bike like I do.

Could it be that simple?

Why yes - yes it is. That's exactly it. :thumb

 

You shouldn't play cricket without a box!!!
I am doing it.....FCR39's...say no more.

 

I purchased the Stage 1 tune from TTP for the 865 Bonneville so just changed filter for a high flow type and removed the air intake snorkel I did not alter the airbox or baffle inside of it with the SAI and 02 stuff completely removed and a set of Norman Hyde classic open pipes the bike runs sweet its lost all of its snatchy throttle issues and pulls nicely through the gears lovely roll on power on tap now.

 

Hardest part with removal was making a new battery holder, and electrical mounts.
Jetting wasnt an issue, but the pods tend to vent out volatiles a lot quicker than the airbox.

 

TTP Stage 2 with ARK here. I keep the side covers on because I'm all modest like that. I did the air box removal because...I could. And, I do think it opens the engine up with the additional air and a rejet. I can hear the DNA filters sucking air but it's not much louder than before. I have the TORS and it's still pretty tame with regards to the sound.

I recommend it but its probably not for everyone. I'm plan on keeping my last-of-the-carbed 2008 Thruxton for long time so I will continue to customize as I see fit.

 

Here’s another view on the original question.
I did full rewiring on my ‘06 Scrambler for a bunch of rational reasons but mostly because I could. Tinkering is a hobby for me. In the meantime, I wanted to keep the airbox. I think it’s a brilliant design. As I installed new, more open exhaust, I opened up the intake side by replacing the OEM filter with a K&N filter. I had a pro do the rejetting the following week as I took the bike to scheduled maintenance service. No problems there. Major power boost.

After a lot of pondering I am now ditching the box. The reason is that it allows for a lot more options for custom wiring and relocation of components. I opted for the TTP version because it seems to be the only one with mounting for original Scram RH side panel bracket. I’ll do the job later this week and take her to scheduled maintenance and rejetting next week.

Wish me luck!

 

Thanks everyone for your responses, I think its only a matter of time before i do this modification.
will update when i make the changes.
I did however change the look and handling of the motorcycle by getting a great deal (I won't say how much these cost) on a set of Kineo rims and Avon Tyres.
The bike looks a lot different, and definitely feels and handles much quicker and better.
Regards Steve.

 

Reviving an old thread, perhaps with a missed viewpoint. I have an '04 carb'd 790 bonnie and am in the market for a new exhaust and matching air intake mod. I dig the simplicity of the TTP Breathe and baffle removal. The minor HP gain from ARK not necessarily worth it to me by itself. But one thing that has me leaning towards an airbox removal kit is the ease of rejetting with pods and no airbox. I find replacing the carbs, particularly refitting them into the airbox rubbers a nightmarish task. The rubber on the airbox is 15 years' old and just not cooperative anymore. One time, okay, but numerous times to make a single adjustment each time (new jet, shim, etc.), I could do without. Has anyone had luck rejetting with carbs still fitted? It seems doable with a short enough, properly sized screw driver; those pilot jets can be tough to crack.

 

Hi Lax,

if you bought our Stage 1 Torque Induction Kit, it comes with the correct jetting kit for the induction and any exhaust changes you have made. So no multiple changing of the jetting.