Noisy motor after valve job
QuoteI did not touch either bolt the holds the cam gear to the cam shaft.
Good
41 minutes ago, g steezy said:I’ll check those other things as you mentioned, but that might be a little bit over my head. I’m an optimistic person, but this ordeal is getting the best of me. I’m running out of things to check.
It is something , someone with good general motorcycle motor and specific DRZ motor experience will likely find.. Its a metallic, metal on metal sound. There will be visual, observable evidence.
The other reason I suggest head removal is it allows the rod to be checked as well..IF, and its a BIG IF, IF the sound you hear is from the rod, the deflection measurement will clearly indicate that as the issue. With that much noise the deflection measurement will greatly exceed the allowed 3mm.
I pulled the head and I think I found the issue. The cam chain was rubbing the cam chain passage in the head. I’m going to replace the chain, both cam guides, and move to a manual cam chain tensioner. I’ll have to do my research on how to tension the manual tenseniors as I’ve never dealt with them before.
I pulled the head and I think I found the issue. The cam chain was rubbing the cam chain passage in the head. I’m going to replace the chain, both cam guides, and move to a manual cam chain tensioner. I’ll have to do my research on how to tension the manual tenseniors as I’ve never dealt with them before.
Read this
https://thumpertalk.com/index.php?/topic/552694-MCCT-Install-guide,-and-Why-one-is-recommended.
Think rocks in a metal coffee can sound when adjusting. You can OVER tighten and make the chain noise quieter but that defeats the purpose.
I painted 1 flat for easy reference.

1 hour ago, ohiodrz400sm said:
Read this
https://thumpertalk.com/index.php?/topic/552694-MCCT-Install-guide,-and-Why-one-is-recommended.
Think rocks in a metal coffee can sound when adjusting. You can OVER tighten and make the chain noise quieter but that defeats the purpose.
I painted 1 flat for easy reference.![]()
That post was Uber helpful, thank you. I’ll order parts tonight and put it back together when I get time. I’m praying this fixes my issue.
Check the cam chain tensioner?
7 hours ago, g steezy said:I pulled the head and I think I found the issue. The cam chain was rubbing the cam chain passage in the head. I’m going to replace the chain, both cam guides, and move to a manual cam chain tensioner. I’ll have to do my research on how to tension the manual tenseniors as I’ve never dealt with them before.
Very good, you found a problem. It would be a shame now to put it back together without checking the rod bearing play and the piston to cylinder clearance. Both can contribute to a knocking noise if they are out of spec. and since you already have the head off, it's not much more work. You seem to have the ability alright to do it. Do you have the manual with the procedure and spec. ?
5 hours ago, bucket list said:Very good, you found a problem. It would be a shame now to put it back together without checking the rod bearing play and the piston to cylinder clearance. Both can contribute to a knocking noise if they are out of spec. and since you already have the head off, it's not much more work. You seem to have the ability alright to do it. Do you have the manual with the procedure and spec. ?
I seem to have the ability, but it's not yet back together and running LOL. I downloaded the manual, I'll take a look and see what I can find as far as checking those things. As long as I don't have to split the cases or something require a very special tool I think I can handle it. Thanks for the heads up.
5 hours ago, bucket list said:Very good, you found a problem. It would be a shame now to put it back together without checking the rod bearing play and the piston to cylinder clearance. Both can contribute to a knocking noise if they are out of spec. and since you already have the head off, it's not much more work. You seem to have the ability alright to do it. Do you have the manual with the procedure and spec. ?
Also note I only have the Clymer manual which I'm not a fan of. I was looking for a manual from Suzuki in PDF form, but couldn't come up with it. I say this because I've noticed errors in the Clymers before more so than the OEM manuals. I hope in information provided in the manual is accurate.
If you paid someone to do that take it back to him immediately and have him open that back up .
4 hours ago, g steezy said:
yes , for those things it is. I've heard it's just cyl. head torque and something else , I forget what it was.
4 hours ago, g steezy said:I seem to have the ability, but it's not yet back together and running LOL. I downloaded the manual, I'll take a look and see what I can find as far as checking those things. As long as I don't have to split the cases or something require a very special tool I think I can handle it. Thanks for the heads up.
3 minutes ago, bucket list said:yes , for those things it is. I've heard it's just cyl. head torque and something else , I forget what it was.
I dont think the spec'ed head TQ in the service manual is a typo, but I do think 43ftlb is better and it works without fail.
The current TQ spec in a service manual not updated for the counter shaft sprocket is 79.5 ftlb, and less then the current spec.. the catch here is, there is also an updated counter shaft that is not center drilled.
Many have confirmed the original design counter shaft easily takes the current spec of 105 ftlb, so Id suggest using that vice what your manual likely shows
If you have the factory service manual update
1 hour ago, Erik Marquez said:I dont think the spec'ed head TQ in the service manual is a typo, but I do think 43ftlb is better and it works without fail.
The current TQ spec in a service manual not updated for the counter shaft sprocket is 79.5 ftlb, and less then the current spec.. the catch here is, there is also an updated counter shaft that is not center drilled.
Many have confirmed the original design counter shaft easily takes the current spec of 105 ftlb, so Id suggest using that vice what your manual likely shows
If you have the factory service manual update![]()
Thanks Erik for clearing that up.
All great, useful info guys, thank you for taking the time to help. I’ll keep everyone up to date as things progress.
40 minutes ago, bucket list said:
Look on the bright side, you'll have a good running reliable bike when you're done and you will have learned a lot.
That is what I'm hoping for as well. I need to check the jug tomorrow and see if it's still round. It has some vertical marks on the walls, but it can still see plenty of crosshatching and can't feel any of the marks with my finger nail.
I do have a question that may be hard to answer. I obviously need a new piston ring, this is supposedly a high compression piston. If it is, does anyone know if it takes the same rings as a factory piston? I don't know the make of the piston so I really don't know what to do in terms of getting a new ring. I wrote some numbers down that were on top of the piston in hopes that they will shed some light on the make.
So did your guy have the jug off when he rebuilt the head?
I would replace the piston with 4795MO9450. 13.5:1 compression is too high unless you're running race fuel. I don't personally have experience with it but that kind of information is readily available on the LT-Z400 sites. The quad cousin uses the same basic engine and is the main reason for many of the available performance parts for the DRZ .
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I did not touch either bolt the holds the cam gear to the cam shaft.
I’ll check those other things as you mentioned, but that might be a little bit over my head. I’m an optimistic person, but this ordeal is getting the best of me. I’m running out of things to check.