DR350 engine noise

My 99 DR350 runs great, starts great but has a noise in the motor. It happens at all rpms, it sounds like a clacking or almost like a valve tapping thats loud. I have read some things like it's normal and will run forever like this, or that it's the cam chain, or to replace the automatic adjuster with a manual one. I am confused about what it could be. I want to adjust the valves, but have seen on youtube a guy did his and the noise was the same as before as it was after. Also, if it is the cam chain adjuster and i've seen that they wear out and are famous for it, can i check it some how, and where is it? Any help or info is appreciated.

To check the condition of the cam chain itself you back off the center bolt on the cam chain tightener (CCT) before removing the CCT. Once the CCT is out you can pull out the little arm and note how many "clicks" are left. If you are down to less than a few it's about time to replace the chain. The chain can get a lot off slack and rub the case making a racket for sure. Jesse told me he saw one once that ate all the way through the case. Sounsd like you need to do something with the bike besides riding it.

i will check the tensioner, but i do not have a manual, so where exactly is it located on this bike?

It is on the rear of the engine on the right side of the bike. I think it will be just above the clutch cover and right below all the fins on the head of the engine. It has two bolts holding it in with the tensioning bolt in the center (all aligned vertically). You will probably have to remove some stuff to get enough access. I thin I had the suspension and swing arm out when I checked mine and was barely able to get to it. I can't remember, but I think you are suppossed to remove the header or something. You used to be able to look at the shop manuals online on Gman's page but it is gone. IF you do take it out you may need a new gasket when you put it back in. They are cheap so you might as well order one. You can order them here on the TT store though they take a while to ship sometimes.

ok, i think i may have discovered something with the noise: I took the valve covers off to see if i can see anything out of the ordinary going with the valves, rotated the engine and saw nothing at all abnormal. No metal shavings or anything loose on all cycles of rotation. However, i did notice the decompressor arm on the engine moving a bit when the engine is running, so i let out most of the cable adjuster to where it was sitting on the block. put it all back together and started it and it smoked like crazy and seemed the "metallic clanging" sound got louder. So I put the cable adjuster back up where it was originally and it quit smoking and the sound went back to it's normal sound level. So, what gives? Exhaust valve out of adjustment? did PO tighten it too much. I am thinking this sound is a mis-adjustment of a valve.

So, what gives? Exhaust valve out of adjustment? did PO tighten it too much. I am thinking this sound is a mis-adjustment of a valve.

Only one way to find out, adjust the valves and set the decompressor correctly per the manual, which you can find here.

Which manual is this. Gman's site had all of them for all the years, or so I remember. Do you know which model and which year this manual is for? Thanks. Good to know it is back online.

It is the factory manual, it covers 90-99.

Ok, i found out the noise is in fact the cam chain. But, it ran great before I made the bone head move of taking out the cam chain adjuster set bolt so now the motor is even louder and I am not going ot run anymore until fixed. But, maybe just as well since running it with a stretched out to the max camchain would have probably destroyed it anyways.

Now, my question is do i change out the chain myself or pay the shop 200 bucks to do which is what they said they can do it for? Never done one, does anyone know if it is a hard job or tricky? any short cuts to doing it without removing the side clutch cover and all that stuff?

Did you run the bike with the screw out?

No, I put the bolt back in then started it for about 10 seconds and turned it off.

Did you ever take out the rest tensioner unit? The point was to remove the center tensioning bolt FIRST so that when you pull the whole thing out you can see what amount of available tensioning was left. There is no point in pulling out the center bolt and then putting it back... Some people weld a blob onto the end of the tensioner to add length to it to get a little more life ot of the chain. Probably not the recommended action but it will tighten the chain up. The chain is stretched out past its service life and will eventually fail. I'm not sure but I think you have to pull the clutch to change the cam chain.

Yea, the clutch cover has to come off, but my local shop is gonna do the whole job for less than 200 bucks so i am gonna let them do it, I already ordered the new chain and gaskets from suzuki through the shop. I'm letting them do it all,that way there is no surprises for me with special tools or anything and they will have it done in a day. Just can't wait to get it back on the dirt again. I did pull the tensioner after realizing where it was, and it was way maxed out.

I was hasty in taking that bolt out without checking to see first if i should, but no matter, they said they will reset the pivot when they do the chain.

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