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About ronbuell

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    I'm just glad I can swing a leg over the seat at my age

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  1. ronbuell

    05 wr250f elec start & carb rebuild

    I had an 03 that quit working. They make a brush kit for the started. If the brushes are worn down, the spring tension against them is much less, so it will get to a point where they don't make good contact with the commutator. New brushes restores contact. https://www.partzilla.com/product/yamaha/5UM-81801-10-00?ref=a26ec4c2ef21ddaa9dc5e360190573af4329d024
  2. ronbuell

    Just picked up 2 Cannondales - advice needed

    If they stand behind their motor bikes like they do their pedal bikes, they're doomed. http://www.soundrider.com/archive/bikes/cannondale_e440.aspx
  3. ronbuell

    Weak Ignition on WR250F

    OK. Don't forget, these bikes will not hold a smooth steady state run. At constant throttle opening under mild or no load, they will pop and stumble like something is wrong. Especially in like 3rd gear just running down a fire road or on a level trail. There's nothing wrong with it when it does that. It's just the way they run. Put a load (pull up hill or high gear low ground speed, open throttle on it) and it'll run normally. It likes a load / pull to make it clean out.
  4. ronbuell

    Weak Ignition on WR250F

    Ok. So... now you're down to a miss-timed cam, or improper valve clearance, or a shorted kill switch. Kill switch is easy, just unplug it. We had an 02 bike, sold it only a few years ago. We upgraded to an 03 cam with auto-decomp on it... never looked back. That's it for me. Last year I was working on an 03 WR, and it was doing similar. Turned out it was valve clearance and cam timing. Once we got it running, issue became carb setup. Main needle was too high letting in too much fuel too early, and it was bogging. I was thinking too lean, but too much fuel was snuffing out the flame. Good luck with it,... let us know what fixes it.
  5. ronbuell

    Weak Ignition on WR250F

    Carb Float height: set to 4mm Slide height: set to .049" Pilot jet: 40 or 42 Fuel screw: 2.5 turns out from closed Main jet 170 or 172 Main jet needle clip: 2nd groove from the top one. JD jet kit main needle: Blue for lower altitudes below 3,000ft; Red for higher altitudes 3,000ft + (see the JD instructions for exact specs Hot start: cleaned, down on the sealing surface, plunger not stuck out (if stock, i.e not swapped for a cable actuated). Remove coil from frame, clean mating surface that grounds to the frame and the frame mating surface for good electrical contact. Make sure you have no resistance in the cable between the coil and the spark plug cap. NOTE: the 02 bike uses a separate coil, not coil on plug. Questions: Is the spark plug black with soot or was the head chamber / piston top black and sooty? When was the last time this engine had a leak down test / new piston installed? I'm thinking it needs a piston/rings and/or cam timing checked, or possible crank if the small sprocket teeth are sharp and pointed (shows up as timing marks are slightly off). Verify TDC by rotating the crank to piston TDC and verify with welding rod or screwdriver down the spark plug hole. When you feel it at TDC, the mark on the flywheel will line up on the mark in the peep hole in the side cover. With that verified (you know the flywheel hasn't slipped, Woodruff key not sheered) you can now verify if the small sprocket teeth are worn. Shows as cam punch marks don't align with the head flat surface. A new cam chain will not fix a worn small sprocket.
  6. ronbuell

    Rear EBC Brake Pad issue

    And the Winner is:......... ChampWazza! Correct answer was Stuck Pin.... or more accurately, there was dried grease collected at the end of the throw that would not allow it to move the full travel. Removed it, cleaned everything back up, slid it together... no more issues. Works great now. So Johnny, what do we have for our smiling winner tonight? Well, he get Kudos from all over for being an expert diagnostician, and many thanks from Ronbuell for a point in the right direction! Well done ChampWazza!
  7. ronbuell

    Rear EBC Brake Pad issue

    Yeah, I've used EBC pads and shoes for decades.... never had any issues. Think I'll cut a cleaning slot in these.
  8. ronbuell

    Rear EBC Brake Pad issue

    Nope, didn't adjust the pedal. I'm betting on the slide pins. Saw it once on a friends bike on the front caliper. Getting old guys.... oh how I miss my mind...... ain't for sissies.
  9. ronbuell

    Rear EBC Brake Pad issue

    Possible. I loosened the screws on the cap and nothing squeezed out. I'll pull it off and try again.
  10. 04 WR250F Replaced the rear brake pads with new EBCs and pushed the puck back into the caliper all the way. The disc will go in, but there is excessive drag like the brake is applied. I noticed they looked wide, but since I didn't have another new set to compare to, I didn't measure them nor do I know what the spec is for a new pad. Never had an issue like this before. Ideas..........?
  11. ronbuell

    06 WR250f Horrible Bog

    Just had a thought.... Have you checked the float height, or have you checked the float valve / fuel line for obstructions ? If you're not getting flow, no amount of jetting will fix it. Sometimes removing and installing the fuel line on the carb will cause a small piece of rubber to come off the line and it will block the float valve. I actually had that happen a couple of times.... maddening because there was fuel in the bowl when I would check. As soon as I started up and ran a few seconds, level would drop and it would lean out.
  12. ronbuell

    06 WR250f Horrible Bog

    If it ran fine before, but developed this, then dirty carb. Is this bike new to you? Working out the kinks? 172 main should work depending on altitude. Higher altitude needs learner jetting. Main needle height may be the issue. I had and 03 and have an 05, and they both needed different needle heights. If the main needle is too high, it will bog (simple fix). Or if the leak jet is too large it will bog. Your fuel screw should be no more than 3 turns out. Usually 2.5 to 2.75 on my bikes and depends on air temps and humidity. If it won't run at 2.5 turns out, then pilot jet may be partially or fully blocked. Slide height also affects adjustments. Standard starting point is .049" open. Also make sure you hot start is not hung open or the cable is not routed wrong and pulling it off the stop.
  13. ronbuell

    Blown 2009 YZ250F Project

    I'd look at the oil in the filter housing, and cut the filter apart and check the oil pump and screen. You are going to split the cases, right? I'd check all the case bearings while I was at it and the clutch as well. Piston looks oil starved.
  14. ronbuell

    Tuning help

    Its a YZ250F, they do that, it's normal. It doesn't have the enriching circuit that a WR has to help prevent that. "Jerky" when riding indicates you need to upshift. Normal Fuel Screw setting is between 1.5 and 3 turns out from closed. Fuel Screw setting and Idle speed adjustment (slide height) will affect hanging idle as well as worn seals on the slide or a hot start that is not fully seated or tight hot start cable. As for hard cold starts, do you wick the throttle to prime it before starting a cold engine, and when was the last time the valve clearance was checked?
  15. ronbuell

    Broken carb float post fix

    Another alternative: You could also go to a hobby shop and get some brass tube w/inside diameter size of the post. Slip it over post, drill small hole thru both to pin it to the existing post and holes drilled right size for the float fulcrum pin.