SXC Exhaust on 03 LC4 Adventurer

[Buckster]

Originally Posted by meat popsicle

Want vs. Need...

Doesn't the Akra push the powerband up the RPMs, making the bike less flexible in the dirt? Might be mistaken on this but I read that opening up the stock Supercrapp with more discs squeezes the powerband up. Big gains will be a trade-off, unless you go nitros oxide gas... now why haven't any of the power-freaks suggested a nitros system???

I makes it more flexible, including an overall increase in torque across the range and peak power occurs about 400rpm lower.

[meat popsicle]

Originally Posted by Buckster

I makes it more flexible, including an overall increase in torque across the range and peak power occurs about 400rpm lower.

Is this the correct dyno? Its from KTM Sommer's website; from the Akrapovics section. Wish they labeled their axes... I am unfamiliar with these things. Guess the taller one is the Akrapovics?

[creeper]

Originally Posted by meat popsicle

unless you go nitros oxide gas... now why haven't any of the power-freaks suggested a nitros system???

http://www.boondockers.com/default.html

[meat popsicle]

Probably could attach it to one of them mapbook buttons.

Sure would be interesting getting it all installed, taking the bike out on a nice lonely flat stretch of road, and pushing the button...

If you replace "lonely flat stretch of road" with mountain side singletrack then either your balls drag on the ground or your nuts. (Is that redundant?)

[Buckster]

Akros chart, peak power 100rpm up but old peak power reached 1500rpm lower, also torque increase is very nice. Should make for a very tractable dirt performer.

[Buckster]

Originally Posted by creeper

http://www.boondockers.com/default.html

Backflips without a ramp.

[meat popsicle]

Originally Posted by Buckster

Akros chart, peak power 100rpm up but old peak power reached 1500rpm lower, also torque increase is very nice. Should make for a very tractable dirt performer.

Thanks Bucky, I believe everyone agrees that the LC4 is restricted and needs better throughput. So I guess the Akras have taken advantage of that - better than all others it seems. So what does 5HP do for us? What does teh dyno look like for the Akra slip on? It would be great if someone had the curves for the KTM silencers to compare. But this still seems like splitting hairs compared to the gains I hear from the airbox, jetting, and just some type of can...

so what's that thing on the Sommer website that I posted above?

[Taki]

I'm a junkie for quality aftermarket stuff, but I find it hard to justify the cost of an Akra for 4 hp. The reality is I would buy the pipe, become dependant on the extra power but regret the noise. Careful jetting has awoken the bike so that traction is the problem dejour. As the urban creep oozes up around us I notice the intrinsic value of a stealth exhaust. More places to ride.

[creeper]

Originally Posted by Taki

As the urban creep oozes up around us I notice the intrinsic value of a stealth exhaust. More places to ride.

Well put, and true Taki.

[creeper]

Originally Posted by Taki

As the urban creep oozes up around us I notice the intrinsic value of a stealth exhaust. More places to ride.

Well put, and true... Taki.

[Katoum]

Originally Posted by meat popsicle

Thanks Bucky, I believe everyone agrees that the LC4 is restricted and needs better throughput. So I guess the Akras have taken advantage of that - better than all others it seems. So what does 5HP do for us? What does teh dyno look like for the Akra slip on? It would be great if someone had the curves for the KTM silencers to compare. But this still seems like splitting hairs compared to the gains I hear from the airbox, jetting, and just some type of can...

so what's that thing on the Sommer website that I posted above?

The HP would be nice, but that Akropovic test was a full system, $1200 plus, what I would like to see is how much power is gained with the KTM Hartparts Akraprovic slip on at half the price. Hell is would be nice to see a test of all the sliponscompared.
I just removed all the disks from my 03 Supertrap boat anchor and it was not that loud, it didn't even sound that bad, I have not ridden it yet, so I will let you all know if there is a seat of the pants difference.

[Stobie]

Originally Posted by Katoum

I just removed all the disks from my 03 Supertrap boat anchor and it was not that loud, it didn't even sound that bad, I have not ridden it yet, so I will let you all know if there is a seat of the pants difference.

You need to ADD discs to reduce restriction, not remove them, my man. They're cheap. A local dirtbike shop quoted me $15 for a 6-pack.

[creeper]

Originally Posted by Stobie

You need to ADD discs to reduce restriction, not remove them, my man. They're cheap. A local dirtbike shop quoted me $15 for a 6-pack.

I believe Katoum may have removed all of it, including the end cap... so no spark arrestor function at all, just the muffler body.

The fact that it is still quiet Katoum indicates that the muffler body is pretty restrictive and the end discs were in fact acting mostly as a spark arrestor rather than sound/airflow control device.
Many of the people that have opted to retain their stock '03 muffler have hole-sawed out the center core, and some have drilled multiple large holes around it's circumference as well.
Mine is sitting in a cabinet in the garage... real quiet in there.

Creep

[Buckster]

Originally Posted by meat popsicle

Thanks Bucky, I believe everyone agrees that the LC4 is restricted and needs better throughput. So I guess the Akras have taken advantage of that - better than all others it seems. So what does 5HP do for us? What does teh dyno look like for the Akra slip on? It would be great if someone had the curves for the KTM silencers to compare. But this still seems like splitting hairs compared to the gains I hear from the airbox, jetting, and just some type of can...

so what's that thing on the Sommer website that I posted above?

The chart you posted is for the jetting and air filter cover kit with stock exhaust.

Here is the chart for the Akrapovic slip on.

[Converted Soul]

If you want to gain power on your LC4 then the way to go is to first buy a FCR and then mount a double muffler (aka rally-replica) exhaust systeem.
Replacing the stock exhaust with a SXC is only for weight reduction.
This is the experience of my single cylinder specialist tuner (Aart Nolen), for example he got 58 rwhp out of a standard 640 with only a FCR, open airbox and double muffler system which he made himself. No head-work, no other cams, no engine work, no timing changes. He gets over 75 rwhp from racing supermono's.