BMW NineT Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
197 Posts
Discussion Starter · #1 · (Edited)
Just ordered the Ti headers. I have a couple questions that I haven’t been able to quite find the answers to with a search.

1. Akrapovic says it’s only compatible with their exhaust. Assuming they say that just so they can sell their exhaust, right? I have a GP-S1...pretty sure it’s fine since it’s so minimalist, but I should be fine right? Just want to be sure.

2. I shouldn’t need the Akra link pipe because of the aforementioned.

3. I’m keeping the flapper valve because of the GP exhaust to SLIGHTLY keep down the noise, there’s no problem there either is there? Will probably delete it later, but for now want to keep it.

4. I assume since there is no O2 sensor beyond the cat, I won’t need a tune? I have a 2019, so there is no Power Commander as far as I know, right?
 

·
Premium Member
Joined
·
80 Posts
You’ll be fine. I also don’t have their exhaust (1) and maintaining the flapper valve (3) eliminates the need for a link pipe (2). I have a ’19 as well and she runs fine without a tune (4).
 

·
Registered
2020 Nine T Classic
Joined
·
74 Posts
I can also confirm that it bolts right in place of the original headers, i'm runing the full decat TI akra headers with the flapper and with the stock Akra trumpets silencer. So if the stock silencer bolts on, every after market silencer should do, at least those that bolts on the stock headers.
You won't need any tune as the stock O2 sensors bolts right on. But as you'll now run without cat, i'd recomend at least running a Booster Plug or equivalent device to enrich your A/F ratio otherwise your engine will be running very lean.
I can confirm that keeping the flapper for a start is a good idea, the bike will be louder, even with a stock muffler .. so It'll be VERY loud with the GP S1 which is close to straight pipes.
Last, make sure you properly clean your TI headers with alcohol before the first start and heat cycle, otherwise iany finger prints or grease marks will stay printed in the coloration of the TI once it gets through the first heat cycles.
 

·
Registered
2017 RNINET
Joined
·
594 Posts
The akrapovic people told me that the header is designed to match B.M.W. mapping and no tune is needed. My bike runs much better with header and is not lean per plug check, as a matter of fact it pops less on decell than stock header. Do contact them for info. and as above thread states make sure you clean them before first startup.
 

·
Registered
Joined
·
197 Posts
Discussion Starter · #6 ·
I can also confirm that it bolts right in place of the original headers, i'm runing the full decat TI akra headers with the flapper and with the stock Akra trumpets silencer. So if the stock silencer bolts on, every after market silencer should do, at least those that bolts on the stock headers.
You won't need any tune as the stock O2 sensors bolts right on. But as you'll now run without cat, i'd recomend at least running a Booster Plug or equivalent device to enrich your A/F ratio otherwise your engine will be running very lean.
I can confirm that keeping the flapper for a start is a good idea, the bike will be louder, even with a stock muffler .. so It'll be VERY loud with the GP S1 which is close to straight pipes.
Last, make sure you properly clean your TI headers with alcohol before the first start and heat cycle, otherwise iany finger prints or grease marks will stay printed in the coloration of the TI once it gets through the first heat cycles.
I read those BoosterPlugs don’t really do anything as the ECU adapts over time? Seems to be a bit of a debate there.
 

·
Registered
2020 Nine T Classic
Joined
·
74 Posts
I read those BoosterPlugs don’t really do anything as the ECU adapts over time? Seems to be a bit of a debate there.
Well, in my personal experience they do work fine. After nearly a year of riding with the de'cat and BP installed i can still feel the effect of the BP.
Once connecting a BP to your bike it'll immedialty make it idle a few revs higher as it simulates a very cold air temperature on a cold start (i'd say aprox 100/200 rev/min higher). It's noticable and if you unplug it it'll immediatly go back to normal. That higher idling stays the same all the time, wether the bike is warm or not.
After a year of riding my bike still idles a touch higher as it did the first day i connected the BP. So i guess that my ECU has not addapted ..
I can aslo attest that it's only the BP that makes your A/F richer and idle higher, not the de-cat. I've riden the bike for a few days without the BP but with the de-cat and it was idling normal.

Wether you need or not such a device once the bike is de-cat is another thread. I'd just say that it's quite a general consensus that any modern vehicule seperated from its original cat' device should need some sort of ECU correction to run accordingly.
 

·
Registered
Joined
·
197 Posts
Discussion Starter · #8 ·
Has anybody used a dyno to confirm? Seems like that would be a pretty simple way to confirm how what it’s doing.
 
1 - 8 of 8 Posts
Top