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Two Bros Exhaust.. Engine remap?

7K views 14 replies 7 participants last post by  conrazy 
#1 ·
Hey guys,

New here, and not the most mechanically minded chap... :), so please go gentle..

A few months ago, I bought myself a 2015 ST3 RX... and have been loving it ever since..

Shortly after i bought it, i wanted to replace the exhaust with something a tad louder (for practical reasons in traffic as much as anything else!), and that was smaller etc..

Read heaps of reviews of the Two Bros Carbon "Slip On" and ended up importing one to NZ from the States..

I fitted this no problem (which for me was an achievement!) and a couple of other bits such as a tail tidy etc.. Found out it was WAY too bloody loud, and then had to import the baffle bit separately:)..

I wasn't sure at this point whether a remap or anything needed to happen, but lots of folks were saying you can, but it's not essential.. (including the triumph dealer, as it's a slip on..)
I ended up going on a reasonably sizable ride around the top of the North Island in NZ, and loved every minute, and other than a bit of backfire and rumble on throttle off or rolling off, all was good!

After got back from the above ~3k KM trip, the bike was ready for it's 10KM service with the dealer (I bought this bike at 8K KM). When booking it in, i discussed with the chap on the phone about the exhaust again, and they said that whilst doing the service, they could upload a more appropriate map for it...

So, i took it in for service.. They mentioned when I collected the bike, that they couldn't find a map for the Two Bros exhaust, but that they loaded a more open than standard map, and that should be fine..

Well, with Xmas and being crazy at work, i've not had much of a chance to ride, but over the last couple of weeks, i've been using to commute a few (non wet) days each week..

What i've noticed is that occasionally, when i'm sitting at a set speed (doens't matter what gear), that the bike will react as if i've started to close the throttle, or as if it's hit a bit of bad fuel etc.. It's not major, but enough to keep me on edge if i'm close with other traffic, or lane splitting etc.
As i thought it might just have been a bad bit of fuel, I ran that tank of gas as empty as i could, and then filled up again, which made no difference.
Like i say, it's not all the time, but just sporadically, and feels a bit rough when it does do it!

I've seen that there are the different ECU maps out there, and that the can be loaded on via a USB cable and the Software etc.

I'm always putting either 95 or 98 RON in there too...

Does anyone else have the Two Bros slip on? has anyone else had similar issues?

Would be great to hear some thoughts on this.

Cheers,
Sly
 
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#2 · (Edited)
I put Scorpions on my 08 and it ran great without tampering with the tune. I had my mechanic load an Arrow high mount tune while at his shop for an oil change, anticipating more power.. Ran horribly after (hesitation during aggressive throttle snaps, inconsistent idle, difficulty starting) and promptly returned to stock.

*I'm on the fourth year with the stock tune and these cans - No problems.
 
#4 ·
Awesome, thanks for the prompt response... yeah, i've actually just found a few other folks talking about similar things on here too!

So, i think firstly, i'll go back to a standard map.

Can i do that myself (i have ordered the USB cable recommended in these forums from the UK), or do i need to go to the dealer again, and have them charge me for the privilege!?

If it's still not right, and or lumpy etc afterwards, i'll look in to the custom map option :)
 
#9 ·
Hi

Sorry I can't really give you any solid advice here, but as I am also in Auckland, I just thought I'd say hello! :p

I remapped my 09 street after replacing the exhaust and did find that the first few days of riding, it was a bit off. By that I mean a slow idle and strange power delivery about 4500 RPM. But then it came right which I assumed was due to the adaptions being re-learned for the new setup.

I was able to do the remapping myself and just went off the manufacturers recommendation (which was for the arrow full system tune as mine was a full system replacement) so maybe you could contact 2 bros and see what they suggest before remapping?

Also, looking at the Dino chart on their site, the power delivery looks a bit strange with that exhaust on, you get less HP and torque below 7500 RPM if I am reading it right, but then you get a few extra when it goes above. So if you are staying below that band, then you may actually be getting less power now than with stock, which doesn't seem right to me.

Anyway, at least the weathers good for riding :)


Ian


Sent from Motorcycle.com Free App
 
#10 ·
Yes the 2 bros is straight through so you lose in the low end with some gains in the top end. So if you're trying to win a race it makes sense. If you are going for general riding, you can't self map a 2015. So you will sacrifice proper fueling in some ranges. Unless you get a pcv with a custom tune. So you might spend $$$ while chasing a tune that will run as good as it was when it was stock.Even then you will get less response I the low end and it may be more jerky, that is more abrupt on-off at lower speeds. Or the idle can be affected being more of a galloping instead of constant rpm or it might start and die.....requiring a second start before it will keep running.
 
#11 ·
The dealer said they put "a more open map" on it? You might want to ask them exactly which map. As far as I am aware there are only two maps for the '13+ bikes, and they are typically referred to as "stock" (imagine that!) and "Arrow", because it was developed for the Triumph accessory Arrow slip-on. Most people who have installed slip-ons and had the Arrow map loaded have had good results. I have a Remus with the Arrow map, and it runs just as well as the stock one with the stock can. There's just a touch of burble off throttle, but I like that.
 
#13 ·
No that you mention it, i'm pretty sure it was the Arrow map...
I've done some more reading, and have since found a few people with VERY similar issues to me, with the S1R 2Bros pipe, and the arrow map, so all kinda adds up..

Will pop back and ask them to put the standard map on, and see how i go from there.
 
#15 ·
I found that my M4 slip-on ran as well if not slightly better than stock exhaust (w/ stock mapping) with the DB-killer installed. It was a little soft in mid range without the db-killer. I switched back to stock exhaust, though, because the stock exhaust has more cornering clearance at the track. Good luck!
 
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