Ticking head - xr600 '90

[Trubbis]

Hi guys

I've been struggling to find the source of the ticking sound coming from my xr600's head.

What's done with the bike:

re-bored to 630, supertrapp, kn filter, stock cam and reinforced valve guides and rockers (I think, anyway it used to have a White Brothers cam)

It was also recently rebuilt/re-bored with new filter and cam chain etc. (all this was done by the last owner)

Doesn't matter if it's hot or cold, ticking follows the engine revs (rev up - faster tick's)

What i've done so far:

Check valve clearance, hardly changed anything, still ticking.

Check cam and rockers for wear - got the engine out of the frame and popped of the valve cover, everything seems OK.. though there was something right on the lobe, the second one from left. But i don't really think it's the source of the ticks.

https://picasaweb.google.com/1128042...09160094/XR600

I'm planning on removing and then put the automatic camchain tensioner back in place, read somewhere here that it might be noisy

Can someone PLEASE help me? I wanna get out in the snow and goof around!

[akarob]

How exactly did you check your cam chain for wear?

[Trubbis]

How exactly did you check your cam chain for wear?

It was replaced along with the other stuff during the rebuild, so i dont think i need to check it for wear It feels nice and tight

[elsalvadorXR6]

hey trubbis I posted an answer on adv for you...

You have major pitting on the cam lobe you posted a pic of...

If you have wear on the corresponding rocker you have your source if the noise...

You also said that you might have hardened rockers and stock cam, you used to have a white borthers cam which is hardened...

I think your noise is from this problem...you have wear.

[Trubbis]

hey trubbis I posted an answer on adv for you...

You have major pitting on the cam lobe you posted a pic of...

If you have wear on the corresponding rocker you have your source if the noise...

You also said that you might have hardened rockers and stock cam, you used to have a white borthers cam which is hardened...

I think your noise is from this problem...you have wear.

hey dude...

you got major pitting on one of your cam lobes...so check the corresponding rocker for wear(the little arm thingies on the valve cover underside)

also it seems like your valve spring retainers are really scratched or something...

anything weird or metal like in the oil?

check that and report back!

good luck

P.S. Is that a stock cam?

edit:

just reread your post you say you might have hardened rockers...maybe thats the reason you have wear on your stock cam lobes...you jave uneven hardness between rockers and cam.

Hmm, you have a point

Didn't think too much about the different hardness (is this the right word :scratch ) in the rocker and the cam..

I have a dude over here in sweden who have a cam for sale, he thinks it's a HRC cam since his bike was hrc kitted but he havent found the original camshaft. Could you guys maybe identify it for me please?

The only marks he found on it is the following:

R1

G

A

And then scribbled Nh4 or something like that.

Is it possible that it's a HRC cam? And do you think i should swap it if so?

[elsalvadorXR6]

nh4 is hrc cam...

dont know about the other marks...

check your rockers for scuffing and or wear...they will make noise if the surface hardness is comprised...

cheers

dont quote me on the cam though...there was a guy on ebay selling one saying nh4 turned out to be a rebranded webcycle cam...with different specs than the hrc cam...

[Trubbis]

nh4 is hrc cam...

dont know about the other marks...

check your rockers for scuffing and or wear...they will make noise if the surface hardness is comprised...

cheers

dont quote me on the cam though...there was a guy on ebay selling one saying nh4 turned out to be a rebranded webcycle cam...with different specs than the hrc cam...

Thanks a lot mate, i asked the guy for a pic so i could upload it here/on advrider

No scuffing or wear on the rockers though! I could take some pics on those too if you like.

EDIT: But swapping to a harder camshaft wont make this happen again right? not necessarily a hrc cam

[elsalvadorXR6]

hey I dont know what I would do...but if your rockers arent scuffed or worn I would just put in a new hardened cam or put a stock used valvetrain(rockers, cam, springs)

Maybe you have heavy duty valve springs too and its just too much for the stock cam?

Its hard to find out what you have...but if one thing is modified it will affect the rest of the components...

OH...DONT BUY A HOTCAM...thats wasted money..jajaja

cheers

[Trubbis]

hey I dont know what I would do...but if your rockers arent scuffed or worn I would just put in a new hardened cam or put a stock used valvetrain(rockers, cam, springs)

Maybe you have heavy duty valve springs too and its just too much for the stock cam?

Its hard to find out what you have...but if one thing is modified it will affect the rest of the components...

OH...DONT BUY A HOTCAM...thats wasted money..jajaja

cheers

That was my plan.

Depends on what i'll get my hands on first and price ofc. I'm not that tempted to tear off the head and change valves etc. Mainly because i want to get out and ride in the snow, and i have no tools for 4stroke (valve-clamp-thingie)

Yep, heavy duty springs as well. I was told by a xr guru on sporthoj.com that the xr love to munch up camshafts and rocker, so i have the same theory as you do.

Thanks for the heads up, i see many of those on ebay, i would like to get my hands on the cam that was previously used in my bike, a white brothers cam. Don't know witch though (if they have more than one kind?) but he said he kicked some husaberg's in the butt with it.

Thanks again

[MentalGuru]

A stock cam requires stock rockers. Harden/welded cams require hardened rockers. Mixing them up will eat a cam.

Heavy duty valve springs work best with hardened cams and rockers.

My personal chose is a Cycle Wizard roller rocker/cam set-up so there won't be cam problems.

He can make custom mild to wild cams or build it to the specs you want, in both non-roller and roller types. He can make HRC spec grind cams also. ?

I like a roller/rocker cam due to it's ability to use steeper ramps and have longer duration at full lift. We discussed using a HRC cam specs for the overall lift, total duration and overlap. The cam will be speced with steeper ramps for more power then the HRC cam makes.

The roller rockers reduce friction and wear issues. Reducing the friction will reduce heat, increase power and engine efficency also.

[Trubbis]

A stock cam requires stock rockers. Harden/welded cams require hardened rockers. Mixing them up will eat a cam.

Heavy duty valve springs work best with hardened cams and rockers.

My personal chose is a Cycle Wizard roller rocker/cam set-up so there won't be cam problems.

He can make custom mild to wild cams or build it to the specs you want, in both non-roller and roller types. He can make HRC spec grind cams also. ?

I like a roller/rocker cam due to it's ability to use steeper ramps and have longer duration at full lift. We discussed using a HRC cam specs for the overall lift, total duration and overlap. The cam will be speced with steeper ramps for more power then the HRC cam makes.

The roller rockers reduce friction and wear issues. Reducing the friction will reduce heat, increase power and engine efficency also.

Thanks! we'll see if i get a kit like that later, but right now i just want to get it running and don't spend that much money on it.

Does anyone know what'll happen if i run with this cam til i get my hands on another one? will i completly ruin the head by making a dish of valve-salad or is it only the cam who will suffer?

[elsalvadorXR6]

dude if you keep using this cam it will wear out and become uneven, this will lead to extra force on the rockers, and even though they are hardened it will destroy them, and it will be quick...once the surface hardened face is destroyed they get eaten up real quick...

plenty of horror stories on rebuilds both here and on adv on what happens to a toasted valvetrain.

I think your cheapest option since everything BUT THE CAMSHAFT is hardened is to get yourself a HARDENED CAM...

then you will have equal hardness valvetrain, see how long this lasts and keep a lookout for a stock valvetrain including stock springs, retainers, etc...

cheers and good luck!

[Trubbis]

dude if you keep using this cam it will wear out and become uneven, this will lead to extra force on the rockers, and even though they are hardened it will destroy them, and it will be quick...once the surface hardened face is destroyed they get eaten up real quick...

plenty of horror stories on rebuilds both here and on adv on what happens to a toasted valvetrain.

I think your cheapest option since everything BUT THE CAMSHAFT is hardened is to get yourself a HARDENED CAM...

then you will have equal hardness valvetrain, see how long this lasts and keep a lookout for a stock valvetrain including stock springs, retainers, etc...

cheers and good luck!

Yep, i figured that was whats going to happen..

Is the Hotcams cam a good replacement for the stock cam? Is it equal to the rest of the valvetrain or as "soft" as the stock cam?

[MentalGuru]

It will put metal particles in you oil system which could cause further engine damage.

[Trubbis]

It will put metal particles in you oil system which could cause further engine damage.

Yep.. The "run standard cam as long as possible" option is out the window.

[MentalGuru]

Yep, i figured that was whats going to happen..

Is the Hotcams cam a good replacement for the stock cam? Is it equal to the rest of the valvetrain or as "soft" as the stock cam?

No Hot Cams... They have had issues with wiping out the valvetrain.

Use a hardened Web cam.

I think a true HRC cam is hardened by heat treating.

You could have a stock cam heat treated also.

[Trubbis]

No Hot Cams... They have had issues with wiping out the valvetrain.

Use a hardened Web cam.

I think a true HRC cam is hardened by heat treating.

You could have a stock cam heat treated also.

Yeah, in school where im studying a welding program we learned how to, and what heat treating does to different metals, it would bee a cool (hot ) project to harden a stock cam to roughly the same specs as a hrc cam or so ?

Ok, ill check what the local dealers have to offer, if i cant find anything ill head for ebay.