9500 rpm Club
#11
The CDI holds it back at 10,500 RPM's. That's all you'll get without a modded CDI. There have been tests done that show there's still more Power to be had above 10,500 RPM's. (Westoz can attest to that). I'd pat yourself on the back for getting it to 10,500. That's a true testimony to a great Setup. I'm completely happy with stock which really doesn't feel good even just over 7,000 Rpm's.
#13
Hey WestOz and gerrynolan. . . I owned a 1967 Kawasaki A7 Avenger 350cc twin, 2-stroke when I was stationed in San Diego in 1967 and just loved that thing. Couldn't keep it running without a spark plug fouling occasionally (didn't know squat about mechanics in those days!) but what a lot of fun it was! Just loved the feel of accelleration when I got into the powerband! Always liked (and still do!) the retro appearance of the early Japanese bikes, especially the Honda 305 Scramblers! Have a good one. . .
#14
While modifying the klx250s to see if there was an improvement my wife an I did afew runs down the freeway.
Going thru the gears she would be bouncing off the rev limiter in fifth abit and never was able to do so in sixth. With the percentage of error in the speedometer she probably hit 72-3 (81 mph indicated on the digital speedo). She hates it when I buzz past on the te450 Husky.
Going thru the gears she would be bouncing off the rev limiter in fifth abit and never was able to do so in sixth. With the percentage of error in the speedometer she probably hit 72-3 (81 mph indicated on the digital speedo). She hates it when I buzz past on the te450 Husky.
Last edited by RaceGass; 03-11-2009 at 07:50 AM.
#20
Piston design
The ignition is the limiting factor. The stock ignition goes flat at 8500 RPM. There are no gains in revving the bike too far past this RPM. The option of custom ignition is just too expensive for most mortals.
Took this info from the ADV sit.
"!. Fitted stock KLX300 barrel
2. Kevin Doyle high comp custom ground piston approx 12.7:1 comp
3. custom ground kevin doyle cams still pulling at 13000RPM nasty
4. Stock ignition opened up to 11750RPM (limited the top HP on my bike)
5. tuff rided (special heat treatment) inlet and exhaust valves
6. D.I.D timing chain ( only need if your going to rev the bejezzus out of it all the time
7. K&N air filter
8. Staintune oversize header and muffler (very loud with cams eh)
9. heavy duty barnett clutch springs
10. revalved resprung forks
11. revalved/stroked rear shock
12. shorter 117mm dog bones
13. FCR35 Keihin, but back to stock KLX250 carby for convenience
I ran this bike in and then took it to the dyno shop. It looked stock and the owner laughed when I told him I thought I would get in excess of 30Hp at the wheel. He even went so far as to show me his hp graphs for stock WR250 Yamaha's. Which on his dyno produced 28Hp at the wheel and 24Nm. The first run on my bike pruduced 34 HP from 8500rpm and 27Nm from about 6500RPM. He fell off his chair and I laughed till I cried. He wouldn't believe it (he thought it was a stock bike with a staintune pipe) so he rebooted the computer on the dyno and we re ran it. Same result and it was funny as it was bouncing off the new 11500 redline at about 170Kph. At this point I had to tell him what I had done. Bear in mind this is with the stock KLX250 carby.
I then fitted up the FCR35 Keihin and we ran it again. I struggled to get the jetting right and it was costing a fortune. But with it running rich all the way through the rev range we got 36Hp and a flat 30Nm. Trouble was it was a pig to ride as I couldn't get the carby right. After about ten million scabbed knuckles, swear words and loss of most of my hair. I went back to the stock carby and sacrificed the few extra hp. The reality is that I'm not fast enought to use it anyway. The civility of the stock carb is like a siren to a sailor. Irresisable.
Kevin ran programable ignitions on the Kawasaki Race bikes and they would not flat line like my bike did from 8500 onwards. However the costs for the programable ECU with the required flywheel mods (loss of electric starter) were too high for me in both $$ and convenience. His bike regularly reved to 13000RPM and they were getting about 40Hp from the 250cc version. YEAH BABY. My bike hit 8500RPM and then held almost the same HP till the rev limiter. The Nm dropped away as the revs increased."
"Use the TORQUE Luke". LOL
Took this info from the ADV sit.
"!. Fitted stock KLX300 barrel
2. Kevin Doyle high comp custom ground piston approx 12.7:1 comp
3. custom ground kevin doyle cams still pulling at 13000RPM nasty
4. Stock ignition opened up to 11750RPM (limited the top HP on my bike)
5. tuff rided (special heat treatment) inlet and exhaust valves
6. D.I.D timing chain ( only need if your going to rev the bejezzus out of it all the time
7. K&N air filter
8. Staintune oversize header and muffler (very loud with cams eh)
9. heavy duty barnett clutch springs
10. revalved resprung forks
11. revalved/stroked rear shock
12. shorter 117mm dog bones
13. FCR35 Keihin, but back to stock KLX250 carby for convenience
I ran this bike in and then took it to the dyno shop. It looked stock and the owner laughed when I told him I thought I would get in excess of 30Hp at the wheel. He even went so far as to show me his hp graphs for stock WR250 Yamaha's. Which on his dyno produced 28Hp at the wheel and 24Nm. The first run on my bike pruduced 34 HP from 8500rpm and 27Nm from about 6500RPM. He fell off his chair and I laughed till I cried. He wouldn't believe it (he thought it was a stock bike with a staintune pipe) so he rebooted the computer on the dyno and we re ran it. Same result and it was funny as it was bouncing off the new 11500 redline at about 170Kph. At this point I had to tell him what I had done. Bear in mind this is with the stock KLX250 carby.
I then fitted up the FCR35 Keihin and we ran it again. I struggled to get the jetting right and it was costing a fortune. But with it running rich all the way through the rev range we got 36Hp and a flat 30Nm. Trouble was it was a pig to ride as I couldn't get the carby right. After about ten million scabbed knuckles, swear words and loss of most of my hair. I went back to the stock carby and sacrificed the few extra hp. The reality is that I'm not fast enought to use it anyway. The civility of the stock carb is like a siren to a sailor. Irresisable.
Kevin ran programable ignitions on the Kawasaki Race bikes and they would not flat line like my bike did from 8500 onwards. However the costs for the programable ECU with the required flywheel mods (loss of electric starter) were too high for me in both $$ and convenience. His bike regularly reved to 13000RPM and they were getting about 40Hp from the 250cc version. YEAH BABY. My bike hit 8500RPM and then held almost the same HP till the rev limiter. The Nm dropped away as the revs increased."
"Use the TORQUE Luke". LOL
Id like to have a look at that piston. Sounds like a very good design with the matching cam. Ive always believed the secret to power is an ideal combustion chamber incorperating the piston head as part of the chamber and good swirl and flame propagation. I dont think a simple round reverse dished piston is very efficient, I bet your piston has good squish areas and valve pockets are exactly machined to match the cam lift