Cam wear/pitting with photos

[Stag10]

So a while back I made a post asking about the stage 2 Hotcams because I wanted to replace my stock cam's which have developed some pitting. I never did take any photos of the wear because I was in a hurry to get the bike back together. Well today I had some time and decided to take the valve cover off and inspect the cam lobes to see if they have gotten any worse and to take some pictures of them.

I cant seem to feel the pitting when I rub my fingers around the lobes, however I do feel a minor amount of bumps when I rub from side to side. The cam buckets appear to be fine with no visible scoring.

My bike is an 08 DRZ400SM with 30,250 Klm, all stock with the exception of a full exhaust, 3x3 and jetting. For those that might be wondering about the bikes maintenance regime, I use Amsoil 10/50 Dirt-Bike oil and change it every 800 to 1000 Klm, I  use OEM oil filters and change them every other oil change. The wear hasn't gotten any worse but would you guys/gals continue to ride it with this kind of wear?

Also, I have kept a close eye on the cam bearings, they look great, there is no sign of scoring on the cam cap bearings at all thankfully. The engine still seems to run as good as it always has.

Edited August 26, 2019 by Stag10

[Thiird]

Im not a mechanic.

From what I can see clearly the lobes are ruined where they touch the valve bucket, so the wear is there because of friction.

Friction should be alleviated by the oil, so this may be an indication that your oil circulating system is not ok, is it ok? Do you put the proper 1.8L of oil in it?

Also I would ask a local bike mechanic.

Edited August 26, 2019 by Thiird

[Stag10]

The oil system is pumping oil just fine, I checked the cam cap bearing surfaces and all is well, oil level always remains full, doesn't burn a drop of oil that I've seen.

Keep in mind that I've owned this bike since 2012 when it just had 4000 KLM on it, it's been babied it's whole life, I've always use top quality synthetic motorcycle spec oil and changed it within 1000 KLM. I was changing the oil filter every oil change up until a couple years ago, then I started changing it every two oil changes.

Also, I've ridden the bike a few hundred Klm's now with the cams like this, I plan on pulling the valve cover off every few hundred Klm's just to see if the cam's get any worse, so far they haven't gotten any worse.

All in all, I'm kind of disappointed in the bike at the moment, seeing as how meticulous my maintenance is and how gently I ride it, it almost never hits the rev limiter, like maybe once a year if someone pulls out in front of me I'll brap-em, but other then that this thing stays off the highway and is kept away from high RPM's 99% of the time.  

Edited August 27, 2019 by Stag10

[roleyrev]

9 minutes ago, Stag10 said:

The oil system is pumping oil just fine, I checked the cam cap bearing surfaces and all is well, oil level always remains full, doesn't burn a drop of oil that I've seen.

Keep in mind that I've owned this bike since 2012 when it just had 4000 KLM on it, it's been babied it's whole life, I've always use top quality synthetic motorcycle spec oil and changed it within 1000 KLM. I was changing the oil filter every oil change up until a couple years ago, then I started changing it every two oil changed.

Also, I've ridden the bike a few hundred Klm's now with the cams like this, I plan on pulling the valve cover off every few hundred Klm's just to see if the cam's get any worse, so far they haven't gotten any worse.

All in all, I'm kind of disappointed in the bike at the moment, seeing as how meticulous my maintenance is and how gently I ride it, it almost never hits the rev limiter, like maybe once a year if someone pulls out in front of me I'll brap-em, but other then that this thing stays off the highway and is kept away from high RPM's 99% of the time.  

Don't stress it.  I'm sure the cam journals would be toast if it was an oil issue.  Maybe the cam hardening was poor or the source metal, it;s not unheard of.  I strongly suggest that you go the Hotcams route you wont be disappointed and it will take you all of then minutes to change them over. You sound like me with how you treat your bike.

[Stag10]

Thanks for the confidence booster roleyrev, because I have been stressing it to be honest.

I am currently looking into the Hotcams, but here in Canada it's looking like both the intake and exhaust stage 2 Hotcams will be over $500.00.

I've even looked into eBay and local classified ads to see if anyone is selling some mint used OEM cams, and nothing is out there at the moment.

I'd be more enthusiastic about the Hotcam upgrade if my bike was running a 39mm FCR, but it's got the stock BSR carb. I cant help but wonder how much more performance the stag 2 Hotcams would give me with such a choked carburbuator. 

[Erik Marquez]

Cam pitting is a common occurrence
Not my words, but of the verious explanations for why it occurs, this is the one that makes most sense to me
 

Quote

The cam in your second picture is not pitted, it's spalled. Corrosion pits are microscopic, and generally difficult to impossible to see with the naked eye. Spalling occurs when a cam or lifter develops microscopic corrosion pits, and then those pits are enlarged by the repetitive mechanical action of the cam/lifter interface. Those microscopic corrosion pits on other components are not significant, but on cam lobs and lifter faces they are critical.

Imagine a brick wall. A properly constructed brick wall can withstand the elements for 100s of years. But once a brick falls out, it exposes four neighboring bricks to attack, so it's not long before one or two of the neighbors fall out, exposing even more bricks to attack. Once this process starts, it's not long before the wall falls down.

Now replace those bricks in the brick walls with the molecules that make up the crystalline lattice structure of the carburized steel cam lobe or the chilled cast iron lifter. It is the lattice structure that gives these surfaces their hardness and durability. Disturb the lattice with microscopic corrosion pits and the surface spalls in exactly the same way that the wall falls down.

How do well made cams prevent the corrosion that creates the micro-pits that lead to spalling?
Nobody has figured out how to make a corrosion-resistant cam (that I know of).

The key is driving regularly to keep a film of protective oil on the surfaces. If the engine remains idle long enough for the oil film to strip off, then we start getting corrosion pitting. 

Other ways include the use of good anti-corrosion oil additives.

But another strong candidate for why we see so many cams pitted, spalled, what ever.

Quote

Camshaft pitting is usually caused when they chrome the lobes of camshafts (and crankshafts) When they perform this industrial chroming (don't think shiny Harley parts, but the shiny surfaces of hydraulic rams) if any bits of dirt, garbage metal such as rust is present on the lobe surface, it will cause the industrial chroming to flake off the surface. (Thus pitting) They do this process to camshafts & Crankshafts to harden the surface & of the lobes & nothing else.

 

[Stag10]

5 hours ago, Erik Marquez said:

Cam pitting is a common occurrence
Not my words, but of the verious explanations for why it occurs, this is the one that makes most sense to me
 

But another strong candidate for why we see so many cams pitted, spalled, what ever.

 

Thanks for the info, I do let my bike idle for a few minutes each ride to warm it up, maybe I should be gently riding it instead.

So I take it I should stop riding it and replace the cam's ASAP? Or do you think it would hurt to keep riding it a few more times?

 

[Erik Marquez]

5 minutes ago, Stag10 said:

Thanks for the info, I do let my bike idle for a few minutes each ride to warm it up, maybe I should be gently riding it instead.

So I take it I should stop riding it and replace the cam's ASAP? Or do you think it would hurt to keep riding it a few more times?

 

I've had motors with hundreds of hours on them come in with pitted cams...cant all of them happen in the last 2 hours of run time.
Yes  Personally Id replace them, but id ride it until them, and out of an abundance of unneeded caution id probable pull the cover after a few ours of use and make sure they are not getting worse. 

[roleyrev]

12 hours ago, Stag10 said:

Thanks for the confidence booster roleyrev, because I have been stressing it to be honest.

I am currently looking into the Hotcams, but here in Canada it's looking like both the intake and exhaust stage 2 Hotcams will be over $500.00.

I've even looked into eBay and local classified ads to see if anyone is selling some mint used OEM cams, and nothing is out there at the moment.

I'd be more enthusiastic about the Hotcam upgrade if my bike was running a 39mm FCR, but it's got the stock BSR carb. I cant help but wonder how much more performance the stag 2 Hotcams would give me with such a choked carburbuator. 

Believe me very similar issues with the cost of things here too.  By the time you look at the part cost (and I buy at 64US cents to every NZ dollar) add freight (there's about $150) and then taxes to land them here, mine cost in the reigion of 750 NZ dollars.  Had you considered OEM from Partzilla?  Use the green item (Kawasaki KLX400r - Green DRZ) the last year for the bike on parzilla is 2004. 

https://www.partzilla.com/product/kawasaki/49118-S008?ref=e6b8828ed7dbf0d91e726fd940c31ae594821345

Exhaust CAM $263 and 

https://www.partzilla.com/product/kawasaki/49118-S009?ref=e6b8828ed7dbf0d91e726fd940c31ae594821345

Intake CAM $134.72

These are "E" spec cams and not to different from Stage 2 Hotcams. Or for one better you could mix and match the OEM exhaust and a Stage 2 Hotcams Intake.

The cams will have an effect even using the BSR - it may not be as much as the FCR.

[Thiird]

1 hour ago, roleyrev said:

Use the green item (Kawasaki KLX400r - Green DRZ) the last year for the bike on parzilla is 2004. 

OMGGGG.

I already knew the KLX400 and DRZ 400 share the same engine, but I never thougth about buying part for my z from the KLX because of the minor cost.

I just checked the cam chain: 70$ for the drz, 40$ for the klx, same exact item.

[roleyrev]

18 minutes ago, Thiird said:

OMGGGG.

I already knew the KLX400 and DRZ 400 share the same engine, but I never thougth about buying part for my z from the KLX because of the minor cost.

I just checked the cam chain: 70$ for the drz, 40$ for the klx, same exact item.

Yup @Erik Marquez put me onto that a while back (thanks Erik).  I bet Partzilla are scratching their heads wondering why so many KLX owners...…. 

[Erik Marquez]

21 minutes ago, roleyrev said:

Yup @Erik Marquez put me onto that a while back (thanks Erik).  I bet Partzilla are scratching their heads wondering why so many KLX owners...…. 

KLX400 parts are starting to become unavailable. I was buying shiftier cam stops at about 2 a week, back ordered each time for about 4 weeks, then the last order, was canceled and status nation wide because unavailable. That led me to check a hand full of other PN.. Sure enough we found a few that are listed unavailable, my parts guy confirmed with mother Kawasaki ...so it is what it is.

[Thiird]

27 minutes ago, roleyrev said:

Yup @Erik Marquez put me onto that a while back (thanks Erik).  I bet Partzilla are scratching their heads wondering why so many KLX owners...…. 

Hahahahah bro xD

1 minute ago, Erik Marquez said:

KLX400 parts are starting to become unavailable. I was buying shiftier cam stops at about 2 a week, back ordered each time for about 4 weeks, then the last order, was canceled and status nation wide because unavailable. That led me to check a hand full of other PN.. Sure enough we found a few that are listed unavailable, my parts guy confirmed with mother Kawasaki ...so it is what it is.

Quick guys, lets collect some money and buy all the most common wear components like timing chain, cylinder and piston, clutch components... xD

[Erik Marquez]

1 minute ago, Thiird said:

Hahahahah bro xD

Quick guys, lets collect some money and buy all the most common wear components like timing chain, cylinder and piston, clutch components... xD

Hey, leave my parts source alone.......

[Stag10]

12 hours ago, Erik Marquez said:

I've had motors with hundreds of hours on them come in with pitted cams...cant all of them happen in the last 2 hours of run time.

Thanks Erik, that is reassuring for the time being until I order my new Stage 2 cams. I figure I might as well go with those as apposed to OEM KLX cams as the savings wouldn't be that much anyways, plus, doesn't the HotCams have a more reliable auto decompression unit on the EX cam? I remember reading some failed OEM decompression stories, yet I haven't heard of any coming apart on the HotCams.

Also, what about the valve buckets, can they be re-used, or do they need to be replaced when changing cams?

[Erik Marquez]

6 hours ago, Stag10 said:

Also, what about the valve buckets, can they be re-used, or do they need to be replaced when changing cams?

The OEM answer is replace cams and buckets... that said, Id look at the buckets close, with what ever you have that magnifies the most..hand held magnifying glass, phone app, microscope... do that under good light..if you dont see anything obvious, Id run them... Keep them in the same bore, so check one at a time or mark them to the bore location (I use the heck out of cheap zip lock bags...buy them by the hundreds on line from ebay or aliexpress)  

[Stag10]

So I took the $500+ dollar plunge and ordered a set of stage 2 Hotcams from my local shop, and.....I'm not too impressed.

The Exhaust cam, somehow, was missing the entire cam gear! My local shop contacted Hotcams and they sent another one out, the replacement does have the gear but still, their quality control had me wondering and worrying.

I chalked that incident up to the fact that most companies have a quality control issue once in a while, no one is perfect.

But then when I went to install the cams, I damn near cut myself on the intake cam, the cam lobes had razor sharp burrs on them. I took a tooth pick and proceeded to de-burr them, but the intake lobes are still sharp, what do you guys think?

 

 

Edited September 19, 2019 by Stag10

[jjktmrider]

That burr shows they don't finish grind them to spec after plating/hardening , no way final grinding would push a burr so bad, they'd be sharp but not much of a burr . I'd hone all those burrs off with an oil stone just to make sure it can't pull up on the plating, though not much of an issue . I just hate companies that sell stuff that'll cut a customer , would love to run one across their baby soft hands to give them the reason for not doing it. All too common these days .

 

.

Edited September 20, 2019 by jjktmrider

[ohiodrz400sm]

$500 CAD??? They can be had for around $350 USD if you shop around.

 

Hotcams used to anodized the lobes black. Another cost cutting move I guess. Although, I don't really know what the value added was?

Hopefully the quality doesn't slip from this company. EVERY S/SM can benefit from at least a Hotcams stage 2 intake IMO. Not every bike needs $300 per piece Web camshafts.

 

 

[roleyrev]

6 minutes ago, ohiodrz400sm said:

$500 CAD??? They can be had for around $350 USD if you shop around.

 

Hotcams used to anodized the lobes black. Another cost cutting move I guess. Although, I don't really know what the value added was?

Hopefully the quality doesn't slip from this company. EVERY S/SM can benefit from at least a Hotcams stage 2 intake IMO. Not every bike needs $300 per piece Web camshafts.

 

 

Yeah $300US per piece + freight + import duty = $1400 NZ  Ouch. Best they be good.....