Short vs Long Exhausts

[Scotty]

Hi all. Pretty much resigned to having to buy a full system for my Gen 2 (due to taking angle grinders to headers seeming quite extreme to decat it....).

I was reading a thread on Facebook where the very knowledgeable peeps at Crowe Performance suggested that smaller big bore exhausts like the AR GP1R/Racefit/SC Project rob the bike of a sizeable chunk of mid range performance.

Seeing as those were the ones I was looking at I'm now questioning it as I'm not prepared to sacrifice midrange on the road. Does anyone have any experience with this and what longer (but not silly long) exhausts are a good alternate?

TIA.

 

[alex]

You're basically looking for something that is in a similar style to the Akrapovic offerings. A long can is going to be ~350mm or more. Any system that needs to be strapped to the passenger foot rest rather than the riders footrest is going to be a "long" can.



Akrapovic, Arrow, Spark.it, Termi all make options afaik.
Or you could contact a UK exhaust maker like MHP or Powertech who maybe able to make you an end can to go with a set of headers.

 

[MrSmooth]

I was reading a thread on Facebook where the very knowledgeable peeps at Crowe Performance suggested that smaller big bore exhausts like the AR GP1R/Racefit/SC Project rob the bike of a sizeable chunk of mid range performance.


TIA.

Perhaps you might consider ringing them up to discuss their perspective? Is it because it will need an ECU mod (Power Commander or such like) and a dyno tune? Can they offer any advice to you? Do they have a solution or suggestion?

Advice is usually FREE, it is the 'How' which costs money.

 

[Scotty]

Thanks Alex. Yeah I had seen that Akro system, very nice.... and price to match!

I just find it odd that there are so many shorter versions available that no one else has said about the midrange problem.

I saw those Spark systems too, never come across them in the past will do some quality digging.

Scotty

 

[Scotty]

Perhaps you might consider ringing them up to discuss their perspective? Is it because it will need an ECU mod (Power Commander or such like) and a dyno tune? Can they offer any advice to you? Do they have a solution or suggestion?

Advice is usually FREE, it is the 'How' which costs money.

Thanks Mr Smooth. They didnt really state a reason TBH. They are quite renowned for being BMW experts. If it was a simple case of a dyno tune and or power commander to rectify it I'd be happy to and go with my original preferred option. Good advice to call them up, I'll do that.

 

[alex]

Torque losses with short exhausts are a thing, this is not bike specific just engines in general, look at MotoGP the very long exhausts on the KTM and Duke etc are to improve torque.
Check eBay for someone selling a Gen 2 Akra.

 

[Scotty]

Good info and reasoning on the Moto GP front. :encouragement:

 

[Corkgsxr]

Also the long pipes are a semi reasonable noise level. Still loud but fine.

Short and full system is very very loud

 

[Scotty]

Also the long pipes are a semi reasonable noise level. Still loud but fine.

Short and full system is very very loud

Are long cans decat loud? Assume these would be just as loud as the full system. I'd like a bit more noise but it doesnt have to be obscene. My decat ZX10R with a short delkevic carbon was very loud and more of a nuisance on long trips than enjoyable. I was going to go full system because all the decats I've seen require chopping up the headers to get the cat off. I do want to ditch the cat to save the weight and it seems to run hotter than my other bikes with it...

 

[Corkgsxr]

I had a yoshi full system with long can and it was a nice level imo.

Buddy had full with racefit and that was mad loud

Some form of tuning is essential. After playing around with others I went with power Commander

 

[Scotty]

Thanks Corkgsxr !