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I went down to a 400 main, definitely has some rip in the upper range, but I'm unable to access the pilot because the bottom of the float is all stripped out (gotta love used bikes). I can unscrew it thru the drain plug, but I fear I'll either drop it in the float or won't be able to get the smaller pilot back in.
What is wrong with the airbox? I haven't heard of this problem?
I've heard buying flexx bars helps with the vibration and adds a little plushness to the front end. I've seen them for pretty cheap some places too.
The jetting I'm currently running in my YZ PWK is a CEJ needle @ middle clip, 178 main, 48 pilot and air screw 2 turns out.
Right now all I've been able to do is go down on the main. Would dropping the needle clip help? I'm still very rich in the middle/bottom, to the point where I smoke, hit the top, then the bike turns into a lean mean beast.
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Another thing the 05-07 CR250 responds well to is milling .030" off the base of the cylinder. This reduces the squish to .050", increases compression and reduces port timing, all of which boosts much needed low end. This mod requires 50% race gas or straight 100LL avgas. If you want to run pump gas, you'll need to add 2.75 cc's of volume to the head's dome after lowering the cylinder.
I have an '04, and I wouldn't be able to do any of that anyway haha but if I got the right specs for the '04 engine, I have a few people who have machine shops that might be able to do it. They're both car shops, but it's just a single cylinder motor, if I gave them the exact specs, it shouldn't be a problem, I'd imagine.
Bear with me here as I try to explain my ride yesterday.
It was my first time actually riding my *new* '04 CR yesterday, and first I must say that this bike is a dream. I already like it far and a way more than my '09 YZ. To each their own.
I was battling rich jetting, so I went down two sizes on the main to a 400. Like I said in a few previous posts, I couldn't change the pilot. I went out for my first moto on the gas that came in the bike, and after the first lap it ran surprisingly well. Still a little boggy on the bottom/mid, but it was snappier than I expected with the rich jetting.
I drained what was left of that old gas and put in my fresh mix of 92 octane pump and 110 octane leaded Sunoco race gas, mixed at about 40:1 with Bel Ray full synthetic. This change in gas changed the way this bike ran completely. It ripped off the middle and pulled so hard on top, it was viagra-like. After I pulled off, I noticed the bike didn't want to idle and the clutch was slipping pretty bad. I had just installed a new Pro Taper perch, and I don't think I had it adjusted enough.
When I went to go start my bike again it was running kind of funny and sounded a little off. I decided not to push it anymore.
Given this information; would you say I fried the clutch because it was adjusted too tight, or did I torch a ring or piston because it was running too lean on the better gas? I am going to check the spark plug, and maybe even take the top of the motor off to take a look at the piston as soon as I get a chance.
Pit Row
I'll try to get a few good pics of the spark plug, maybe even the piston head and clutch plates asap. Just gotta find the damn time.
Race fuels generally run richer than pump, unless they're oxygenated, and Sunoco 110 isn't oxygenated. Oxygenated race fuel, like VP U4.4, runs much leaner and usually requires 2 jets richer to compensate for high oxygen content.
I drained the oil and it seemed like it was low and the oil was pretty deathly black and wasted looking.
Pulled the clutch cover off and this is what I'm looking at now.
Grooves in the clutch basket. What do you guys think, file or replace?
Locking nut in the center of the flywheel. Do you think this was intentionally flattened? It's on the two opposite sides.
To my surprise, the plates looked brand new. These are the two furthest back, and all the rest in between look pretty solid like these. No signs of discoloration, on the friction plates at least.
This is the plug. It wasn't terribly bad, considering how rich it was running when I first got it, but I changed it anyway. What's peculiar to me is it was not the same number plug as what I've looked up. When I checked it said the model for this bike was a BR8EG, same as my YZ. It had a B8ES I want to say in it. They looked identical, so I'm not sure what the difference was?
Anyone running pump gas in a smoker should look at that expensive plug out of the RM125, when it detonates, the ground strap wont fall off and ruin the engine.
if you put them old fibers in a new basket, there will still be a fore/aft gap as the clutch rotates and the new basket will wear very quickly.
also, the inner hub looks grooved too.
with clutches, its often best to replace everything at the same time, unless you just smoked the plates, but even then the springs will sack out from the heat and the inner driven plates might warp.
are those inners steel or aluminium? i would use steel...luckily for you, OEM honda parts are reasonable cost. ive never heard anything good about aftermarket clutch plates, apart from Pro_x which i believe supply the OEMs; ive often used EBC spring sets since you can save a little there.
Go ahead and laugh, but i went to take the cylinder head off and in my own stupidity I removed the water hose and lost a lot of anti freeze. Do i have to do anything in specific to get the system pressurized again?
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