Top end noise??

Hi folks,

Just re-shimmed my exhaust valves recently, the bike was fine afterwards for a while but now makes a distinctive and fairly loud ticking sound which seems to be coming from the top end. It seems louder if I put my ear up by the rad (from the front). I don`t think it`s the MCCT and wondered if it could be to do with the valve springs??

It`s a bit louder than the soft tick of valve clearances. At first I thought it was the exhaust blowing from a bad seal at the head, kind of sounds like that, but the exhaust gasket is new - I replaced it hoping it would do the trick, but didn`t work.

My bike (2005 DRZ400S) has an Anthena 440 kit, MCCT, hotcams stage 1, FCR41, MRD/SSW and so on. Has 22500 kms on the clock, about 7000 since the big bore. Will check the valve clearances again (did it when the engine was cold before) on Friday. Re-shimmed it to the hotcams spec.

Any ideas??

you should consider adding new valve and springs [ RHC ]

you have done some miles on the stock oem ones and added a big bore kit and cams

Any other spring options other than RHC?

It is much better to have loose valve clearences then too tight. I'd suggest putting the old shims back in, for a test, without hearing the sound. I doubt very much it is the springs.

Any other spring options other than RHC?

RHC are the standard. With your mods you don't want to skimp on sub par valves & springs.

Mike :thumbsup::thumbsup:

I doubt very much it is the springs.

Why is that?

I doubt it's the springs because you have low miles on your bike but maybe you do a lot of hardcore off-road riding. It sounds like to me the valve clearence is too tight or your cam timing is off.

toadl, I don`t do any hardcore off road riding so hopefully you are right about the springs. Will check the valve clearances today but I only just did it a few weeks back, clearances were a little tight on the exhaust valves so re-shimmed then.

Correct me if I'm wrong but as I've understood the closer you get to the larger extent of the range the noisier the top end will be.

Valve clearence gets tighter over time, not loser. If it was tight when you checked it, it will only get worse. It's better to have them on the loose side. I learned this the hard way because I thought the tighter my tolerance the more valve lift I'd have.

decompressor pin.

Eddie, thanks for your input. After doing some quick research I`m sure this is the problem, but how do you go about fixing it? Not even sure where the pin is exactly, I guess on the exhaust cam??

I also read that it could also cause inaccurate valve clearance readings??

Have another issue now with a mangled rotor nut plug....

you need to cut the auto decomp unit off the exhaust cam

chooken, can this be done with a hacksaw and is it easy to do? Can`t I just replace the pin or would that be a bad move? Is cutting the auto decomp unit off the best solution?

you probably cannot 'fix' it. Either replace the exhaust cam with a new one or remove the broken compression release from the existing one.

chooken, can this be done with a hacksaw and is it easy to do? Can`t I just replace the pin or would that be a bad move? Is cutting the auto decomp unit off the best solution?

i used a dremmel and extreme care to remove it , you could buy a new cam .

many DRZ's have them and with no issues , i just prefer to remove the possible problem cause

could the decomp pin be whats wrong with mine?...(Check my other link about "whats this knocking sound")

could the decomp pin be whats wrong with mine?...(Check my other link about "whats this knocking sound")

Is yours 'knocking' or 'ticking/clicking'?

It is very quick to check the decomp. Remove seat, tank, and valve cover and have a look. If you search there are threads with pictures.

chooken, can this be done with a hacksaw and is it easy to do? Can`t I just replace the pin or would that be a bad move? Is cutting the auto decomp unit off the best solution?

As chooken said, just cut it off. Wrap the cam in cling film to stop any crap getting in them. Rags and a soft vice to hold it and just take your time. It can be done with a hacksaw and doesn't effect the starting. just be careful, but it's an easy job.

As chooken said, just cut it off. [highlight] AFTER REMOVING FROM ENGINE [/HIGHLIGHT] Wrap the cam in cling film to stop any crap getting in them. Rags and a soft vice to hold it and just take your time. It can be done with a hacksaw and doesn't effect the starting. just be careful, but it's an easy job.

You really don't want fillings in the engine.

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