g steezy

Noisy motor after valve job

90 posts in this topic

New member looking to be a long time member also looking for some guidance. 

 

Short story for those who hate to read, I had new valves installed and got the bike bike and it was very noisy. I can't seem to find what the noise is. 

Video of noise: 


For those of you who want to back story, here it is:

I bought a 2000 drz 400 a few months ago. It wasn't pretty, but had a ton of money in quality aftermarket modifications. Modifications that may be worth mentioning on this issue are hot cams and a high compression piston. Any how, I bought it and it was a terrible chore to get started, but once started it ran well, and would restart when warm. I rode it for about 4 hours one day, that's it. After doing research I found that tight valves were most likely the issue for the hard starting. I've adjusted valves before on my DR650 a couple other bikes, but I've never had to deal with the shim type adjustment. I didn't feel like messing with it and took it to a friend of a friend who races bikes and is a mechanic by trade. He told me that valves were pretty worn and recommended new valves be installed, which I allowed. After getting it back it sounded like the video above. Note it didn't sound like this before, but I will admit it started easy. I told him it didn't sound right and asked him if he could check over his work. He came and got it and said it sounded like the noise is coming from the bottom end and  he advised to tear into the bottom of the motor. I honestly didn't think it was coming from the bottom end and it wasn't sounding like that before so I went it picked it up and decided to check it out for myself.

I've checked the timing and it looks correct. I checked his valve clearances and the intake is perfect at .15mm and the exhaust is just out of spec tight at .18mm, but that shouldn't be causing this noise. It still has the automatic cam chain tensioner and it seems fine. I put a scope down the spark plug to check to see if any valves had touched the piston, but couldn't see that well, but I don't believe they have. I took both engine covers off to look for debris or obvious issues, but couldn't see anything. My kickstarter gear somehow fell out when I took my side case off so I need to figure out how that goes back in. As of now that's where I'm at. My next step was going to be to button it up and see if the noise is still present, but I'm sure it will be as I haven't made any changes. 

Any advise on where to go from here? Any help would be greatly appreciated. 

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1st :Cams mis timed?, check again, assume nothing, pretend like its the first time you have seen the bike and don't know how to check, read the procedure and follow it. 
2nd: Cam chain tensioner is not working (ACCT) not adjusted correctly (MCCT) (I dont think this is it, the chain sound when its loose and slapping is, well different and is not constant  at on/ off throttle )

3rd: Is your manual decomp working correctly? Is it partially engaged? Broken?
You have a non normal sound timed to RPM.... and recent head work.... something is wrong, its not your imagination.  

If it was a rod knocking, it would have been there before the head was done.  It did not get that loose sitting in your garage waiting on rebuilt head.
 

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What shim thickness were used to adjust clearances ? 
Were the new valves check for installed height?
Were seats replaced or old ones cut?
Did you install a new spark plug with the fresh head? Are you sure its the correct one?
Was the head surface ground?
Was the cylinder and piston removed and replaced when you had the head off?

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15 minutes ago, Erik Marquez said:

1st :Cams mis timed?, check again, assume nothing, pretend like its the first time you have seen the bike and don't know how to check, read the procedure and follow it. 
2nd: Cam chain tensioner is not working (ACCT) not adjusted correctly (MCCT) (I dont think this is it, the chain sound when its loose and slapping is, well different and is not constant  at on/ off throttle )

3rd: Is your manual decomp working correctly? Is it partially engaged? Broken?
You have a non normal sound timed to RPM.... and recent head work.... something is wrong, its not your imagination.  

If it was a rod knocking, it would have been there before the head was done.  It did not get that loose sitting in your garage waiting on rebuilt head.
 

1. I thought it was possibly mis-timed so I moved everything over a tooth and re-rechecked. That made it even more out of time so I put it back to how it was. 

2. Cam chain tensioner is working, it's an ACCT

3. I'm not very knowledgeable on the decomp. I did put a feeler gauge under it while at TDC with no resistance so I figured that should tell me it's not engaged.

 

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26 minutes ago, Erik Marquez said:

STOP RUNNING IT

I ran it like that for the video and that is it.

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The Decomp works by rotating a pin that depresses the cam cap slightly ..if the decomp assembly is not fully returning to the "open" position, that pin in smacking the cam cap 
Timing.... well, its correct or not.... you say it is, so........
ACCT, ok, so with the valve cover off you have confirmed the chain is tensioned? Good
If all correct so far, its gets deeper.... shims to thin, wrong valves, bad install, the crank large or small end bearings went bad sitting in your garage...or something else 

 

1 minute ago, g steezy said:

I ran it like that for the video and that is it.

I figured i just wanted to get that up right away, did not even read the rest of your post before writing that....

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4 minutes ago, Erik Marquez said:

The Decomp works by rotating a pin that depresses the cam cap slightly ..if the decomp assembly is not fully returning to the "open" position, that pin in smacking the cam cap 
Timing.... well, its correct or not.... you say it is, so........
ACCT, ok, so with the valve cover off you have confirmed the chain is tensioned? Good
If all correct so far, its gets deeper.... shims to thin, wrong valves, bad install, the crank large or small end bearings went bad sitting in your garage...or something else 

 

I figured i just wanted to get that up right away, did not even read the rest of your post before writing that....

I kind of saw how the decomp worked. If I can leave a small feeler gauge under it and it never get tight I assume it should never be hitting.

Timing looks good to me as far as I can tell. The cams are aftermarket so it's not exactly like manual.

Seat in the head very not bad, ground a bit. Kibble white valves were used. He doesn't remember the exact shim sizes or valve stem heights. 

He's adamant it's in the bottom end. Maybe he's right, but he's either wrong or it was the biggest coincidence ever that the bottom end went out right after a valve job.

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Posted (edited)

To me it sounds like something is hitting or rubbing on something , like a guard rubbing hard on the cam chain . Does it sound like it's coming from the right or left side ?  Bad crank has a distinct sound that sounds like it is deep in the motor , not that tinny tick you have .  I can't believe how bad some guys will refuse they did something wrong and just walk away from it , I'd not be friends with him ever again .

 

Take the center plug out on the stator cover and use a 17mm socket to spin the motor over slowly (take the sparkplug out) . Listen and wath for anything the make a click , clank , snap ect.. at a slow speed .

 

.

Edited by jjktmrider
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I agree with JJ. I think something is loose or put together wrong. Maybe the plastic cam chain guide isn't seated correctly?

 

DRZ's run 10's of thousands of miles without a valve adjustment. The fact that the exhaust is tight means either your buddy set it wrong or it's tightening up already. Once you solve the mystery sound keep an eye on the valves to make sure they are staying put. If they keep moving you will need the valves redone again by a professional.

 

 

 

 

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Post the timing marks of your cams. If they are paint marks then they should be set so the dots at 9&3 and level with the head surface. If they are drilled spot marks into the sprocket then they should be set same as stock.

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1 hour ago, ohiodrz400sm said:

Post the timing marks of your cams. If they are paint marks then they should be set so the dots at 9&3 and level with the head surface. If they are drilled spot marks into the sprocket then they should be set same as stock.

 

Notice how the marks are a hair off? I thought it could be out of time so I moved everything over one tooth and that made the marks further off than on. I am just assuming the painted on lines are just a little off. 

IMG_1088.JPG

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3 hours ago, jjktmrider said:

To me it sounds like something is hitting or rubbing on something , like a guard rubbing hard on the cam chain . Does it sound like it's coming from the right or left side ?  Bad crank has a distinct sound that sounds like it is deep in the motor , not that tinny tick you have .  I can't believe how bad some guys will refuse they did something wrong and just walk away from it , I'd not be friends with him ever again .

 

Take the center plug out on the stator cover and use a 17mm socket to spin the motor over slowly (take the sparkplug out) . Listen and wath for anything the make a click , clank , snap ect.. at a slow speed .

 

.

I was going to see if anyone was going to say it, but you did. The cam chain guide is about the last thing I could possibly think of making noise that would be top end related. I don't know how it could be in there wrong or incorrectly however. It seems to work with the tensioner as it should. I also have cranked the motor over by and and I cannot replicate that sound. I don't really know what side of the motor is noise is coming from, when I heard it the first time I shut the bike off quickly only to start it again for the short video I posted above. I was afraid to leave it idle while searching for the sound.

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Notice how the marks are a hair off? I thought it could be out of time so I moved everything over one tooth and that made the marks further off than on. I am just assuming the painted on lines are just a little off. 
IMG_1088.JPG.6e5d7b375f36fc3b1d6d3e1577b6c51c.JPG

Do you have the line centered in the window or the T? It's the line that needs to be centered. Looks like from the picture if you moved the cams a tooth the dots at 3 o'clock would be below the surface. Is that what you see? If the flywheel line is in the center than the error is likely from cam chain wear.

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1 minute ago, ohiodrz400sm said:


Do you have the line centered in the window or the T? It's the line that needs to be centered. Looks like from the picture if you moved the cams a tooth the dots at 3 o'clock would be below the surface. Is that what you see? If the flywheel line is in the center than the error is likely from cam chain wear.

To be honest I got anal about getting the line centered in the sight hole or whatever the term is for that. What I noticed is that little distance from the "T" to the line made really no difference. When I moved each cam a tooth to the right it made it even more out of time so I moved it back. Now if these marks are in an unexceptable location for timing then I suppose there is a problem. I also noticed that the cam gear just bolts onto the cam shaft, not really loving that as I would worry they could come loose. If they ever were to come loose I would be one lost puppy to how to set them back up.

5 minutes ago, ohiodrz400sm said:

Double check he has everything assembly with the manual de-compression release correctly

Check, I will do my research on that and check it out more thoroughly than my ghetto slide a feeler gauge under it. 

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HotCams put loctite on the bolts from the factory. I wouldn't worry about it.

 

If the unlikely did happen Hotcams will re-time them for free. I sent them an old style stage 2 exhaust cam and they timed it to be an intake for free.

 

I used to have the same cams. They looked similar to yours until I changed the timing chain.

 

 

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48 minutes ago, ohiodrz400sm said:

HotCams put loctite on the bolts from the factory. I wouldn't worry about it.

 

If the unlikely did happen Hotcams will re-time them for free. I sent them an old style stage 2 exhaust cam and they timed it to be an intake for free.

 

I used to have the same cams. They looked similar to yours until I changed the timing chain.

 

 

Great info, thank you. May I ask you how you knew you cams needed to get re-timed? Also I assume you're saying your cam chain was stretched and mine may be as well? I guess the cam chain tensioner wont take up the slack? Is a stretched cam chain a common issue? I'll check my manual to see if there is a method for checking the chain and its tolerances. I noticed a chain isn't stupid expensive and I noticed you don't have to split the cases like you do on my DR650 to install a new one. Perhaps that's something to look at as well. 

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Great info, thank you. May I ask you how you knew you cams needed to get re-timed? Also I assume you're saying your cam chain was stretched and mine may be as well? I guess the cam chain tensioner wont take up the slack? Is a stretched cam chain a common issue? I'll check my manual to see if there is a method for checking the chain and its tolerances. I noticed a chain isn't stupid expensive and I noticed you don't have to split the cases like you do on my DR650 to install a new one. Perhaps that's something to look at as well. 

How did I know? The old stage 2 cams (2003-1IN & 2003-1E) were the exact same cam with different timing. Hotcams discontinued them a decade ago but I found a couple exhaust cams new on eBay.

Yes to the stretched chain. Although the tensioner will keep it tight on the sprockets, the distance between chain pins has increased and thus slightly changed the timing between the crank and cams.

Replacement is fairly straightforward. Remove the engine case, clutch, remove primary gear bolt, slide the gear forward, replace chain and re-assemble.

Yes to stretched chains being common. The 2003 and later DRZs have an updated cam chain tensioner that has more tension than it needs. These however replaced the original design (which you may have) that was venerable to failure.

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16 hours ago, g steezy said:

 

Notice how the marks are a hair off? I thought it could be out of time so I moved everything over one tooth and that made the marks further off than on. I am just assuming the painted on lines are just a little off. 

IMG_1088.JPG

The marks are off slightly because the cam chain is worn somewhat. Its like that on EVERY motor that has a used cam chain, more so on one that uses the ACCT.

Im sure Im off, but, just to be sure... you did not loosen those cam sprocket bolts to "adjust" timing right?

That is an older set of cams to have adjustable sprockets...

Look at the left ex valve follower (the bucket) is it scratched and dinged up where the decomp pin presses against it? 

If you can not find the issue...... Id suggest investing in a head gasket, pull the head, check for contact of valve to piston closely, measure installed valve height, check the shim thickness and look at the underside of the followers to see if you can find evidence of contact between the spring tops and follower. 

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