[kazanakius]

Before I beggin, i want to apologize for creating one of those regular exhaust threads which are frustrating to many people in here.

I have been searching this forum for at least 3 days, many hours a day!
I found some really helpful information.. BUT did not answer all my questions.
Yes I looked at doublen's exhaust reference thread, but didnt find the answer!
Yes I looked at tuneECU thread and didnt find the answer!

So i summarize them here, and I hope to get some answers because I am about to make an exhaust mod and I am feeling dizzy!

I bought a stock header from which I want to remove the cat and the exup.

I have 2 unanswered questions!

1) Should I leave the 02 sensor pluged and working? Yes or No, and why?
2) Is there a custom map for deleted cat & exup, with aftermarket slip on? 2008 Daytona 675 - TuneECU in my hands.
I have heard that Arrow tune is too rich and TOR tune is too lean for this set up.

I saw the great job that KEGSdale did, but looks kind of difficult for my ability. Also he made a short exhaust which probably needs different tune than long undertail.

I would really appreciate your help.

I am lost here!

Regards,
Thomas

 

[kazanakius]

Thank you very much for the e-mail SIW!

 

[kazanakius]

Maybe you should pm SIW for that. If you have a Tuneboy, i think you will get what you want.

If i manage to upload to my bike a good custom map, I will certainly share it with you.

 

[kazanakius]

If you have a TuneECU or a TuneBoy then you can disable 02 sensor and have no engine light turned on.
From what I was told, there is no serious reason to remove the O2 sensor. You might get a very slight performance increase, but the engine will lose its ability for a slight adjustment considering the air temperature etc.

So I will just leave it pluged.

I think that IF by leaving it pluged , you get some unstable idle issues, you can just turn it off from TuneECU-boy, and check if that fixes this issue.

I do not have personal experience from all these, I ll know very soon when I do this mod. I am just telling you what I understood by reading others.

 

[kazanakius]

So, I removed exup and cat today!

I changed my map from TOR to Full Arrow system.

My mechanic told me that the bike will be runing rich and that it will lose power instead of gain, if I dont make a custom map.

Do you think that my bike is now runing worse than it did before?

I really cant understand any difference yet!

I will have a comparison dyno very soon, but until i do, i hope i get some answers from you..

 

[kazanakius]

when i just hit some open roads, and I think that i gained power. It felt more agressive, and did 2 power wheelies!

I will have a dyno soon to check out. I was thinking though that if the arrow tune is too rich then maybe some more air intake would be fine, so I am thinking buying a BMC Race air filter to replace my K&N filter.

Also what i have noticed is that the idle while the bike is cold, is unstable and changes between 1.000 and 2.000 rpm, a few seconds at each. why...?

 

[kazanakius]

Thanks Dale
I will post the "before and after" numbers as soon as I have them :nod:

 

[kazanakius]

The idle is high and unstable only while the bike is cold. After it warms up, it idles fine. Do you still think this is the problem? Would the manual idle adjuster fix this?

 

[kazanakius]

Well.. I had the dyno run today. These are rear wheel numbers. 2008 Daytona 675

• Red line is with Arrow slip-on and TOR Tune

• Blue Line is with Arrow slip-on with removed cat and exup from stock headers with Arrow system tune 20421.

I am a little satisfied as it seems to have gained a little here and there, without losing anywhere. I was hoping for something better though.

I will do an other dyno run with a custom map in a few days. I hope that it will be even better.

What do you think of the results?

 

[kazanakius]

Hey man, that is impressive. With a good tune you will probably see another 3 or 4 and it will be a smooth curve. There's still some room up top for a little more ingition timing too...you should download the 90001 race tune and use its timing curve. It's been proven on a dyno 2+ whp.

I really hope so! Not that it matters very much, but I would really want to see something above 110rwhp with some tweeks. Next 2 dynos will be with BMC Race filter instead of my K&N. The first with Arrow tune and the second with the custom tune.

We spent yesterday on the dyno with a race tuned 675R testing a few extra mods.

So what I'm saying is a dyno should only really be used to set a bike up. There are so many things that can alter the final figures and make you happy or sad.
The bike is a full supersports spec 675R, the dyno operator works for some of the top teams in the UK and does dev work for companies like Motec.
The small gains we are looking for like 1 or 2bhp are big figures when an engine is as highly tuned as this.

What do you think ofmy results though? You have probably seen many 675 dynos. Are me 107rwhp normal for my mods? I have heard that the Fuchs Dynometers are a little "strict". Are they? (compared to dynojet)