We are not going to know what the new 300 can do until someone pulls out the secondary throttle plate, pulls off the airbox lid, bolts on a full exhaust system, and creates/verifies 12.7 - 12.8 to 1 fueling, across the board, at WOT.

The KLX250S as done-up above, goes from 18 - 20 hp to 24 hp and over 16 lb ft trq - which will give yall's lightly modded 300's a run for their money..


Soooooo.. the sooner the better guys..

 

You could sure give mine a run for the money as our numbers are quite similar.

Since the last dyno test I made these changes:

1. Secondary Throttle Plate Delete
2. Primary Throttle ECU Control Spring Delete
3. Pair Valve Delete
4. KDX Snorkel
5. Delete Smog Cannister, Valves and All Hoses
6. Iridium Spark Plug
7. FMF Megabomb Chambered Header
8. 25% Longer (40 Inch) Exhaust Pipe
9. Three Tuning Disks

Still busy with work. But I'll dyno test again when I get the time, and am eager to see how much difference in torque the nine mods make working together.

It's kind of an all day ordeal as I need to ride cross town through traffic to get there. And even though I make an appointment, I still need to wait around the shop for a few hours until they get around to testing it. It's a very low priority item as they're always really busy doing way more important shop work prepping bikes for races. Nevertheless, I'm happy to hang around and watch what the technicians are doing.

 

Tooter, the problem with your setup is that it is non-standard. Your personal mods to your exhaust system have re-tuned the acoustic and pressure wave scavenging (timing) of your exhaust system.
I am afraid this will alter your power charts from those with a standard full FMF exhuast system - rendering your results unpredictable compared to a standard full FMF exhaust result.
Also, as usual, until the airbox lid is removed and fueling reset, we will not know anything regarding possible top power levels,

 

I am expecting to see a lidless, MegaBomb+PC4, secondary delete, PCFC fueled properly KLX300 to hit 27 - 28 ("ish) hp and TRQ bebop'ing in the 18's..
The power curve should be raised over the entire RPM range allowing such a bike to run off and hide from lesser builds.

 

It's a non standard setup because I'm a non standard rider.
But that's not a problem because my bike perfectly matches my uses.

Are there any power charts for a full FMF exhaust system? So far I've never seen one. Since I bought my FMF Megabomb header from a random one-off ebay sale, I have never seen another one for sale online since. Strange...



Even FMF has had zero in stock for a year that I know of, and I have absolutely no idea why. You'd think they could sell a fair amount of them. All you can do is send them your email and they'll let you know IF they ever make more.

Making the exhaust 25% longer has drastically altered the timing of the reflected pulses which should produce a more torque while reaching its peak at lower rpms. I'll be testing this theory on the dyno. And yes, the results will definitely be unpredictable because no one else has ever done this on a klx300 before.

You're right, what I'm doing will not yield any useful information about high rpm performance, because I'm not chasing after top end horsepower, but rather low rpm torque.

The radial exhaust design is radically different from standard "beer can" exhausts. The rings have an inner and an outer edge which create slightly different width openings. The pressure differential between them creates a scavanging effect on the exhaust gasses. The billet internal cone smoothly guides the linear exhaust flow radially through the rings.



When the eccentric inventor, Paul Moller first marketed his Supertrapp designed exhausts in 1971 he was really onto something. There is simply nothing else like it..

Why not get a 300 yourself? In all my years of riding, it's the best bike I've ever owned in my life. You'd be totally free to take it in exactly the direction you want. I'll bet you'll have no end of personal satisfaction and fun doing it.

I know I am.

 

Tooter,
Any updates? I ran a Supertrapp on my 1974 BSA B50MX and can remember how tunable it was. From high torque low rpm with about 4 discs to explosive power with 8 discs or so - memory fails me now as that was 48 years ago. What model Supertrapp do you have, their website doesn't identify any specific Kawasaki model. I recently purchased a 2007 KLX250s with a TM36-68 pumper carb. I have a BB 351 kit on the way.
Thanks,
NWrider76

 

Good memory.

I run 3 disks on my 300 and it's quiet while not being restrictive.



Dyno tested it with 8 disks which is wide open. I still haven't dyno tested it with all the mods yet. Work has kept me busy.

 

Tooter,
I wasn't able to read the information on the outer cap of the Supertrapp to see what model it is - none is shown for the KLX on their website, but it may be the same as for the DR350 Suzuki or perhaps the CRF 250/300's - My KLX has the 300cc header pipe. BTW my BB 361 kit should arrive tomorrow.

 

Sorry, none exist.
I used to custom make those exhausts and sell them, but have been unable to get more parts.

 

Too bad about that but, I've enjoyed reading about your experiments with your system and look forward to your next dyno results.