Secondary butterfly removal.....help.

[macvisual]

I've heard it mentioned regards lifting the tank and air box on a DL1000 to get at the secondary throttle body butterflies, if these are (carefully) removed it helps gain a little more brake horse power and adds a lovely deep air box snort sound, hmmm I'm nearly moist just thinking about it.

Has anyone here done this task on their DL1000 V-Strom..??


Would love to hear views/thoughts/experience please, appreciated.

[2112]

I did it and it's not terribly difficult. The Vee is restricted via the ECU (and under certain conditions by the secondary butterflies) in the lower gears to stop cack handed wheelies etc and by the secondary butterflies in fifth and sixth gear. Basicaly you open the throttle but nothing happens because the engine is not getting the full flow of air due to the butterflies closing. To access these you need to remove the tank and air filter. If you look down the two inlets you will see a round disc slotted through a bar & retained in place by two small screws, this is the secondary butterfly. Carefully remove the screws, ideally with a magnetic screwdriver and the push down on the butterfly to turn it and grab the edge and remove. Repeat for the other one and replace the airbox and tank. You have now removed the 5th & 6th gear restriction and it will now fly !
A word of caution, Suzuki did this because they had some worries about stability. Make sure you bike is tip top before exploring the upper reaches of the tacho in 6th !!! Mine had the Hagon springs with the forks dropped through the yokes about 15mm and +25mm jack up dogbones at the rear and it was quite stable, only getting a little bit 'floaty'. All done on private roads of course...  

[macvisual]

Thanks 2112;

So your saying it's a worthwhile mod to do with benefits..? Yes..?

I just don't want to do this and find out that it goes like a pig or upsets things like fuelling, possibly misfires etc, running rough overall, that kind of thing if you understand me.

Did you do this to your 650cc or 1000cc V-Strom? I've heard it say it gives a good 5 to 10 more brake horse power, wOOw that's healthy OK.

[Gassoon]

Macv, 2112 did this on his 1000...forwhatitsworth, if I hada Vee I would do this too.

Heres a link whichmight be useful to you (basically an expansion, with photo, of what 2112 said more concisely!)

http://www.vstrom.info/Smf/index.php/topic,10844.0.html

I would do it! No power remapping or owt afterwards either!

[Juvecu]

This has the same effect as fitting a TRE, removing the 5th and 6th gear restriction (correct me if I'm wrong?), and a lot of people do that. If you have a TRE, remove it after doing this.

[donny1972]

The tre removes the restriction from 1st to 4th gear if I remember correctly.

[kevshek]

So just to clarify, this here in the picture.....


Is the secondary throttle plate we are removing?
Just the name suggests to me its the second thing id comes across whereas this is up top when you remove the filter.

[donny1972]

That's them alright. Let me know if there is much difference in performance

[macvisual]

Good photo kevshek,

Question time; so when you remove those two tiny brass screws how do the actual butterflies come out, by pulling?

And the butterfly pointing downwards, it looks tricky to remove as its downwards..!!?? So how's this removed I would like to know?


Thanks for all replies....gret stuff.

[kevshek]

its not my pic mate I pinched it from the other thread.
Usually, once the 2 screws are removed, you rotate the valve so it then points up and just slide it out the the bar.

[2112]

So your saying it's a worthwhile mod to do with benefits..? Yes..?

I just don't want to do this and find out that it goes like a pig or upsets things like fuelling, possibly misfires etc, running rough overall, that kind of thing if you understand me.

It's not going to affect the running of the bike because it does not change any of the engine mapping. It only stops the secondary's from closing as they're not there. The engine runs as well as ever. You don't get any extra power from this but you don't lose power as you do when they start to close. The engine will make as much power as it does on 4th (the only gear it's not restricted in).

As it costs naff all it has to be a worthwhile modification, especially with a 43 tooth rear sprocket  

[2112]

Question time; so when you remove those two tiny brass screws how do the actual butterflies come out, by pulling?

One you have the screws removed push down on one side and the butterfly will move, get it at 90 degrees to closed and simply slip it out of the cross bar, jobs a good one  

[Juvecu]

And they are called 'secondary' because the primary butterflies are the ones operated by the throttle (the secondary ones are actuator operated via a servo motor.)

[donny1972]

So if it does not give you anymore power then what is the point in this mod?

[Juvecu]

Not being restricted in any of the gears.

[donny1972]

So otherwords if you have a tre fitted then there is no point in removing the butterflies?

[hookie]

Good question? I'm now getting confused- nothing new according to her indoors! I thought a TRE (Timing Retard Eliminator) stopped the ignition fully advancing in all gears except top, oestensibly to make the bike less powerful and more controllable. I thought removing the secondary butterflies just ensures that the ECU can't restrict intake airflow, especially when you have the throttle wide open and want maximum power. I thought the two are conrolled independently but should work together to get the best performance the engine is capable of?

[2112]

So otherwords if you have a tre fitted then there is no point in removing the butterflies?

Probably not as the bike think's it's in 4th gear all the time, although you should get a bit more airflow with them removed. As Tesco's say every little helps...

[donny1972]

Help iam confused.com  

[kevshek]

From what I understand, tre derestricts 1-4 (aswell as 5 & 6) timing wise.
Secondarys derestrict 5-6 air flow wise.
Do them both, your derestricted in all gears. Happy motoring!