2003 400ex making weird noise please help

[LBo]

i have a 2003 400ex with a slip on exaust, amr cdi and coil, 14 tooth front sprocket, 55w hid headlight conversion kit, trx450 front shocks,pro armor nerf bars, velocity air filter...... ever since i changed the cdi and coil the bike makes a weird noise when it kills cold... it only makes the noise sometimes.. it almost sounds like loose metal in the exaust header. ive checked it twice and there is nothing in the header.... i cant find out what this sound is and it seems to be getting a little louder over time... please help!!!!!

[dxcody]

only when cold right?

Could be a valve rocker arm tapping from being loose.

Check your valve clearances.

[derekhonda]

If it's just some rattling metal, check everything. Those heat shields on stock headers sometimes loosen up a smidge, but I'd just go over everything.

[Longdong]

Check the clamp on the exhaust pipe.

[JOHNDOE83]

Originally posted by LBo
i have a 2003 400ex with a slip on exaust, amr cdi and coil, 14 tooth front sprocket, 55w hid headlight conversion kit, trx450 front shocks,pro armor nerf bars, velocity air filter...... ever since i changed the cdi and coil the bike makes a weird noise when it kills cold... it only makes the noise sometimes.. it almost sounds like loose metal in the exaust header. ive checked it twice and there is nothing in the header.... i cant find out what this sound is and it seems to be getting a little louder over time... please help!!!!!

Completely remove the exhaust and header and see if it still does it?

[LBo]

I thought ur not suppose to run the bike with out the header on??? If it stops Wat could it b

[JOHNDOE83]

Removing the header and running the motor wont do anything to hurt it, it will eliminate anything with the exhaust as the problem.

If it still does it, You need to check valves and cam chain and make sure all is still good.

If it stops when you take the exhaust off, then check the heat shield bolts and slipon and rattle around the exhaust untill you find the problem.

Do you know if the exhaust header crush gaskets were replaced?