Is there any experience here with this system? The dyno sheet is missing but the claim is 4.9 HP with a bone (covers and plumbing in place) stock klx250! It's a stepped header and a megaphone to muffler design.

Steve F

 

I couldn't find a pic of their header, just the tailpipe and muffler. I can't believe their claim of basically 5 horsepower. You notice their statement, "typical peak HP gain of 10%-25%". Typical to what?...a KX? I can't see any way you strap this pipe on without opening up the airbox and installing a better carb needle and get much of a gain. I see you're using their "possible" 25% claim, but I think that's in the stratosphere on our KLX. It's probably closer to the 10%, but even then that's nearly 2HP without any other mods.

Here's the deal...if you do some really effective exhaust mods to our bike, it's still stuck with an EPA carb needle and a restrictive intake. I think their "typical" gains are based on bikes/ATVs etc. already equipped with performance oriented equipment. If I studied their charts correctly, the KLX250 was the only street legal bike shown among their motorcycle applications...the Buell aside. These guys seem more involved in UTV/ATV/Snowmobile vehicles. I'm sure the exhaust is better than stock, but I'd be shocked beyond rational belief to see a dramatic improvement over the many other quality systems already available for our bike.

 

True true, Just wondering that they may have arrived at the *perfect* contours and lengths to yield up more hp. You Know- to some extent it's like an Easter egg hunt with us. Oil, headers, tires but real is real.

Steve

 

And no...I'm not knocking this brand/system out of hand. I just doubt it's going to be an earth-shaking breakthrough in performance. The quality "looks" good. The mounting appears somewhat unique with what appears to be a "banded" design with possibly a heat resistant rubber or similar material within the clamp. Like to hear/see more about that.

 

I have a complete picture of the system but I will have to wait for my tech support Valentine to get home to attach it to a reply.

 

Sound level: Typically 103 dB without the silencer, and 94 dB with Quiet Core insert (with a loss of only 1.5 HP you might want to run the Quiet Core all the time!).

If you get a 10% power gain and then loose 1.5hp with the addition of the quiet core, you don't have much of a gain. 103db is loud, plus now you will have to repack the muffler on a regular basis.

If you open up the exhaust for more air flow, the intake MUST also be opened up to get the air into the engine. Appropriate jetting also needed.

For $600. there are other mods that can be done to help the bike.

Ride on
Brewster

 

~5 hp gain from exhaust alone?...haha..i wouldn't buy it just because of the ridiculous claim....

 

These statements are on all the bikes. Looks like they just copied and pasted from KX model to the KLX.

•Construction: 304 Stainless Steel, tig welded with seam-reduced interior surfaces for smooth flow
•Power: Reverse-cone megaphone with pulse-wave tuning technology for superior peak horsepower, enhanced over-rev and improvements throughout the rev range. Typical peak HP gain is 10-25%.

•Weight: Significantly less than the stock system.
•Features: Removable aluminum heat shield standard, riveted aluminum Barker's badge. Optional Quiet Core and spark arrestor inserts.
•Sound level: Typically 103 dB without the silencer, and 94 dB with Quiet Core insert (with a loss of only 1.5 HP you might want to run the Quiet Core all the time!).
•Options: Ceramic coating for pipe. Powder coating for silencer. Ask us about colors.

 

Stock these bike put out 16-17 rear wheel hp, 10% is 1.7 more 15% would be 2.5hp over stock. My powercore4 by it's self was in that ball park without jets. My bike is an 09 and the stock exhaust was a butt plug. I have seen afr's on stock bikes that were rich not lean which would explain way I felt such a boost with the slip-on alone. When I modified my air box and added the dyno jet kit it didn't make as big a difference as the slip-on alone.

 

Is getting the OE 300 adjustable needle and seperate OE jets (if necessary) still a proper and accepable way for us to start and fine tune the carb.?
I would rather do this than a kit_ just my preference.

Thanks....Steve