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What happened with my bike?

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I'm brazilian and I bought my new 04'CRF250R last august. Last weekend, after one lap, I listened a strange noise in the motor and my bike stops in the middle of the track! I knew that was something wrong so I roll it to the pits and wait the motor to cool down. After that, I tried to start again and after 20 tries it starts and stops. I was very worried. Went back home straight to garage to see what was wrong. The bike is brand new almost six hours of use. It's my first four stroke, so I was careful, I changed the oils after four hours of use. I opened the head cover and saw some marks in the contact point between the rocker arm and camshaft. I moved the kick start and I listened a strong CLICK at every rotation of the camshaft. I thought that was something wrong with piston or rings. I never opened a motor like that and Heckler's post about "how to check the shims" was very helpful. But after check if the cam lobes were in the right position, the marks in the chamshaft gear were aligned to the head and the point in the gear shown in the right crankcase hole were aligned to the mark, I proceed to dismount the cam. But I realized the two of the four bolts of the cam holder were loose! Just to simplify, I disasemble the head, the cilinder and I saw that nothing was wrong The piston and therings were OK. I assembled all again. When I mount the cam (perfect aligned and tightened) and moved the kick start, I listened to the click again. I think the marks in the rocker arm was caused by this part: the "decompressor" inside the cam who has a flat and a round surface in each side. When I was moving the cam I couldn't see if the decompressor rotate to its flat side to touch the rocker arm (is that right?). I think the cam rotation moves the rocker arm to press down the exaust valves, but when the decompressor contact the rocker arm there was the CLICK. I don't know if this is right but it seems to move the rocker arm up and down very fast causing these clicks in the top of the exaust valves. If this movement is the right movement, what makes this decompressor rotate, so its flat side stays in the right position to touch the rocker arm?

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The click your hearing is the auto decompressor working. It goes into the cam once the engine starts running with centrifugal force. The click you here is normal. Is it getting gas and spark?

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i know the sound you mean mate!

i heard i after putting my 450 back together, when u rotate the cam from cold the auodecompressor unit is engaged and when the rocker rolls over the decompressor pin it clicks. i thought my decomressor pin was worn but it seemd they are like this from new. obviously ou wont hear it when its running as the decompressor aint engaged.

as for the other noise you heard what did it sound like? where abouts did it seem to come from? is it still doing it before it cuts out? hows ya oil levels?

as for the cuting out i'd check the obvious:

spark plug lead (check plug is tight)

killswitch

cdi plug

also check the 5/6 connector plugs by the carb comming up from the stator. i had one loose on mine.

:cry:

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check and make sure that the wires going in to the coil thats part of your spark plug cap are not loose. one of my friends had one of his wires loose from the factory (and some other people too).it causes the exact symptoms that you are describing. it was something with the solder broken on the pin in the coil portion of the cap.

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My 04 CRF 250 is in the shop right now. There is clacking nois coming from the tranny. It all started one day I was riding and the back will just locked up. But the bike was still running (so it didn't blow up). It took a few min. to get the gear shifter unjambed to go into Nuetral. I drained the tranny fluid and found small chuncks of metal and plastic/ or rubber (not sure).

Haven't heard from the shop yet to see whats wrong with it. Probably gunna cost alot of money!

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