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Kalkaska Sand

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About Kalkaska Sand

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    TT Newbie

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    Michigan
  1. Here's an actual one popped into my head, Q: "Do you find you ride slower after you got hurt?" Me: "No. I was already slow before I got hurt." (meaning, this recent injury was not the first, or the second, or the third, or the most spectacular, ...or the fourth, etc.)
  2. RobotMachines:applause: Even the manufacturers are getting creative! Scroll down and look at the Bu*ll picture: http://ktmtalk.com/index.php?showtopic=245024&st=240
  3. Yesterday, I rode at the same location: 900 feet above sea level and 70 degrees, dry very sandy dirt. 93 oct MI pump Gas at 32:1 using Maxima Super M. This time, I used a BR8EIX (Iridium) spark plug. Main 390 (again, suggested above by JD) Red Needle 3rd Groove Slow Jet 32.5 (stock) Air Screw 1.25 turns out The engine ran very well without flat spots or bogging out of the corners. Although I was riding trails, the corners were ramped-up by quads and 2nd and 3rd gear tight. – And I was riding over my head and really whipping it thru the corners. (That bike can turn!) I am using 14/49 sprockets and the bike felt smooth and strong. The modification by Eric Gorr was for more low-end power...or at least to get rid of the dip in the low-end dyno curve. I can remove the (thing ) that the Main Jet screws into, but I don’t think the nozzle can be removed/changed on this ’04 carb. The ’04 carb also has a throttle position sensor so I don’t want to mess with changing the carburetor. The Jetting Kit indicates the Red and Blue Needle are ½ clip position apart from each other. It reads, “The suggested sequence to test the jetting from richer to leaner is Blue #3, Red #3, Blue #2, Red #2” Everything works well. Along with MCR Suspensions modification, this bike is a blast. ...and I learned something. Thanks!
  4. Per your instructions, I installed a 400 Main. I set the Red needle at the 3rd. I checked the plug from a high-speed shut-off and it looked a little too white. Air temperature was about 65 degrees F. Dry deep sand. There was just a little surging so I turned the Air Screw to 1.5 turns out. Still not quite right, but close. I moved the Red needle to the 4th position and the bike came alive! I will probably try the Blue needle at the 3rd position for my next ride (this will be leaner by ½ clip position). Now, fancy this: The instruction sheet that came with the JD Jetting Kit told me to start with the 400 Main and use the Red needle with the clip in the 3rd groove. So, the suggested jetting on the Instruction Sheet was only off by ½ clip position ...and this might be because the air was only 65 degrees F. Maybe next time I will stop trying to out guess the experts. What made me wonder was the fact that the Instruction Sheet and clear plastic box do not specifically read that the Kit is for a "2004" CR250R. (I bought the Kit thru Rocky Mountain ATV/MC and I thought they might have given me the wrong Kit) (I understand how much trouble it would be to label every Instruction Sheet.) It is just that the JD Jetting Needles looked so radically different from the pair of (stepped) needles that Honda included with the bike: 6CHY12-82 and 6CHY13-82
  5. Thanks! Once I have throughly tested, I will report back here. I have Eric Gorr's "Motocross & Off-Road Performance Handbook", 4th Ed. and I am following his "Ride and Feel Method." My only experience with jetting in the last 12 years has been with my 1993 CR500. – And it is not nearly as sensitive as this CR250. Mug Shots: That’s the perpetrator strapped down on the dyno all right!
  6. Yes, I just wanted to be safe. The bike came with a 420 Main and I am riding in sandy soil with a 14 tooth front sprocket. I also suspect that the gasoline contains ethanol in place of MTBE as part of the 2006 EPA Regulations. I experienced surging when I let off the throttle, bogging out of the corners and detonation in 5th gear on hardpack. Off-idle seemed OK. And it did not seem to rev out well. That could be the porting work and the Boyesen Rad Valve Reeds. I just wondered if I was missing anything on the baseline. I don’t have any experience with this bike, so that is my main problem. (Many modifications on a bike I am not familar with + inexperience = jetting difficulties) I read here on TT that James Dean actually dyno tested a 2004 CR250R, so I have faith that his Instruction in the JD Jetting Kit were correct. I should have tried a 400 Main. Instead, I spent all my time messing around with the stepped needles that Honda supplied with the bike. I plan to head to the trails in a few days and resume testing with the JD Kit. The discrepancy in the carb numbers has me guessing. It might mean nothing, I just wondered if anyone knew these carbs that well.
  7. I purchased a JD Jetting Kit for my new ’04 CR250. Ports were lowered slightly by Eric Gorr. Boyesen Rad Valve Intake and Boyesen Exhaust Flange. The Owner’s Manual lists the carburetor as a TMX11A, but the Mikuni carb itself has “TMX10A, A, W363” written on it. Can anyone tell me what might be different between an “11A” and my “10A”? The float level is listed as 7.5mm for the “11A” listed in the Owner’s Manual. Is this measurement correct for a “10A” carb? (I believe it is.) The reason I ask these questions I tried the following (preliminary) JD Jetting with poor results: Temperature 70, Elevation 900 feet, damp sandy dirt, 13/49 sprockets, 32:1 Maxima, fresh 93 Octane Michigan Pump Gas (Contains Ethanol). Main 410 Red Needle 3rd Groove Slow Jet 32.5 (stock) Air Screw 1.5 turns out (stock) I realize the 410 Main might be too rich and I plan to check a 400 Main (as recommended by JD Jetting Instructions). If anyone has answers or baseline jetting advice, I'd appreciate it.