01 CR250 cutting throttle slide

[YZhallsme]

Originally Posted by junteschan1

YZhallsme,
Sorry for the late reply. Yes, I still have the S-4 installed combined w the 6beh173 oem needle on 3rd; I still will have to test the same with the A/S
2 turns out after which I go to try 4th clip....
I have yet to find the time maybe this month should be better.
How about your end? have you tested yet lately compared to the jd kit.
Thank you.

No test yet just around the block to warm up and then adjusted airscrew. Must admit I'm a little concerned about being lean after your report of burnt metal smell. I didn't noticed anything while warming it up but afterwards, when adjusting the airscrew I did see a few drips from the radiator overflow tube. Currently- 370 main, 27.5 pilot, S-4 nozzle, stock #4 slide, stock 6beh1-73 clip#3

FWIW I tried again to take some measurements of JD red vs. stock needle, can post or pm you what I came up with if you want.

[YZhallsme]

I managed to get in 50 miles with the stock 6beh1-73 needle in clip #3, S-4 nozzle, 27.5 pilot, 370 main, stock #4 slide, airscrew 2 1/4 out. Elevation was @ 8,000' and @ 65*. It ran pretty good, didn't notice any sign of being too lean, no overheating, no bog or flat spots, no decel surging. However this was with 100 octane Sunoco, not the usual pump premium.

[junteschan1]

Originally Posted by YZhallsme

I managed to get in 50 miles with the stock 6beh1-73 needle in clip #3, S-4 nozzle, 27.5 pilot, 370 main, stock #4 slide, airscrew 2 1/4 out. Elevation was @ 8,000' and @ 65*. It ran pretty good, didn't notice any sign of being too lean, no overheating, no bog or flat spots, no decel surging. However this was with 100 octane Sunoco, not the usual pump premium.

At least your engine was still running cool at 65F and 100 octane....
Mine I expect at probably 90F w 91 octane....let you know of course.

[YZhallsme]

Update- Back to 91 pump premium, everything else remained the same. Only rode 17 miles at @ 70*, 8,000' and dry. I also attempted the "Wet Oil Line" or is it "Pull The Pipe Method" of checking 2 stroke jetting but I couldn't distinguish the line (I'll keep trying). No signs yet of being too lean while riding, airscrew seemed best around 2.25 out, think I'll try a smaller pilot next time. What I did notice at the end of the day was that while the spooge running down the outside of my silencer looked to be the same, the inside of the silencer looks as if it's drying out! This is the first time I've ever seen that on this bike. Also when I got home I pulled the plug, the metal portion at the base of the threads was dry, another first!! Not sure what to make of it though???

[VAL]

Update: Barstow California, Saturday June 20 and Sunday June 21, elevation 2100 ft, temp 90F Saturday late afternoon, Sunday morning, 65 early-85 by noon.

Ran soooooooooooooooooooooo great. Crisp, clean, linear. Bottom to mid end was "electric", mid to top she would sing, I really mean sing, the pipe would actually resonate with this, most beautiful note. I love it.

Only had to adjust the air screw 1/8 turn out to get her to idle like a champ.

Got around 25-29 miles to the gallon.

Plug was a little dark but acceptable. The only smoke visible was a very light wisp right after a wrap of the throttle.

I have only had her out on the track since I did the jetting. I am not a good enough rider to wring her out on the track so I really didnt know how well she would run for long periods of time in the top end of the throttle. This weekend proved that you can make one of these pesky Mikuni's run great thanks to JD.

[bundyho1]

So you say you can get the bike to idle good with the jd kit .Im in heavy debate on whether to go with the jd kit or 38 airstriker .....Im at about 900ft above sea level and temp range from 60 to 90 when i ride,what would be a good starting point with the jd kit?

[junteschan1]

Originally Posted by VAL

Update: Barstow California, Saturday June 20 and Sunday June 21, elevation 2100 ft, temp 90F Saturday late afternoon, Sunday morning, 65 early-85 by noon.

Ran soooooooooooooooooooooo great. Crisp, clean, linear. Bottom to mid end was "electric", mid to top she would sing, I really mean sing, the pipe would actually resonate with this, most beautiful note. I love it.

Only had to adjust the air screw 1/8 turn out to get her to idle like a champ.

Got around 25-29 miles to the gallon.

Plug was a little dark but acceptable. The only smoke visible was a very light wisp right after a wrap of the throttle.

I have only had her out on the track since I did the jetting. I am not a good enough rider to wring her out on the track so I really didnt know how well she would run for long periods of time in the top end of the throttle. This weekend proved that you can make one of these pesky Mikuni's run great thanks to JD.

Hey VAL,
With this ride of yours....what are your specs again....
many thanks of course.

---------- Post added at 10:30 PM ---------- Previous post was at 10:12 PM ----------

Originally Posted by bundyho1

So you say you can get the bike to idle good with the jd kit .Im in heavy debate on whether to go with the jd kit or 38 airstriker .....Im at about 900ft above sea level and temp range from 60 to 90 when i ride,what would be a good starting point with the jd kit?

bundyho1,
one thing i noticed w the mikuni tmx is that the needle jet is easily removable and will allow various sizes for your choice of tuning. whereas, the keihin a/s is fixed i think .....tinkering with it is the fun side of it and some 01cr250 owners such as val,yzhallsme & myself get to give us test results thereafter....
really many thanks to them...my bike runs much better and im having more fun.
Good luck to you....

[bundyho1]

Gota give thanks to val ,hey i noticed on the service 250 honda that it has a pwk carb on there.Im still undesided ..

[VAL]

I am running 380 main, JD red needle, clip @ 4th from top, 4S nozzle, 25 pilot, air screw 2 5/8 out (at 2100 feet) and idle screw ~ 1/4" of threads showing past the lock nut.

[junteschan1]

Originally Posted by VAL

I am running 380 main, JD red needle, clip @ 4th from top, 4S nozzle, 25 pilot, air screw 2 5/8 out (at 2100 feet) and idle screw ~ 1/4" of threads showing past the lock nut.

val,
many thanks....you and YZhallsme have been very helpful doing the tests on this tmx carbs......appreciate it.