I always used stock valve clearances, make damn sure you set the decompressor clearance right, that is with BOTH feeler gages in place, when you tighten the locknut.



Tell ya what, I got a head I know for a fact is good setting here with a stock cam in it, I could shim it and send it to ya if it would make you rest any better.

Double check this video for reference.

http://www.hotcamsinc.com/index.cfm?fuseac...o&videoid=2

 

My head is ported and polished, I was wrong on the 120 thing though, they are 220's so I'm going to try adjust them down a bit and see if that fixes my issue. I have it all apart now I just need to do the math and put the right shims in. Do you think this is what is causing my knock at high rev?

 

Link in sig...

The page also has a link to a valve shim calculator.

 

Ok I have them all in spec except the decomp side exhaust, it's at .33 instead of .28, problem is I need a 210 shim and there aren't any in Steve's kit. I have a 205 in it. Am I safe running that a little loose or do I need to get a 210 in it?

 

a little loose is okay. remember they'll tighten back up.

 

a little loose is okay. remember they'll tighten back up.[/b]

Yeah but I'm so anal about this build that I want it to be right, I'll try to pickup a 210 shim today while I still have the valve cover off and get that last valve set.

No one has told me whether my stock springs are ok or not though, I have the money for KW valves and springs if I need them but I was hoping to put that towards new tires and a few other non-necessity items.

 

curious about the springs as well...

 

curious about the springs as well...[/b]

It's like everyone reads the question but avoids the answer, who would I need to speak to on this because I've contacted a local repair shop and he didn't know the answer either.

 

index.php?act=findpost&pid=474222

curious about the springs as well...[/b]

It's like everyone reads the question but avoids the answer, who would I need to speak to on this because I've contacted a local repair shop and he didn't know the answer either.
[/b]

If you are running stock valves with the HC II, I would run stock OEM springs. Although I would probably order new OEM springs if you have significant time on yours. (OEM valvesprings are pretty inexpensive)

If you switch to the heavier KW stainless valves is when I would run the heavier KW springs...

JMHO, take it for what it's worth....

Kris

 

If you are running stock valves with the HC II, I would run stock OEM springs. Although I would probably order new OEM springs if you have significant time on yours. (OEM valvesprings are pretty inexpensive)

If you switch to the heavier KW stainless valves is when I would run the heavier KW springs...

JMHO, take it for what it's worth....

Kris[/b]

Thanks Kris, that's kinda what I'm looking for but I planned on doing a whole change over to KW if that is necessary. When there is a strong load on my motor it doesn't knock, so if the motor is pulling it's fine but it seems as the top end levels off and I hit 3/4 - full throttle I get a knock up in my valve train, I'm stumped as to what the cause is and was curious if it was due to running a ported and polished head, aftermarket exhaust, and HCII but still on the stock valves and springs. Or if maybe the issue was caused by my valves being too tight.

 

...

 

Hey Jeremy, I'm not sure what the problem is but do know that many members on here run similar mods with OEM valves and springs. So, I think your okay there... it's really only when you up the rev limiter or use an aggressive cam that they become suspect.

With that said, I did not read this entire thread and do not know how old your valves and springs are. But like Kris said, the OEM's are pretty inexpensive. Might be worth switching them out for some new ones. I also agree with him on the KW springs. I would not mix them in with your OEM valves, I would either run all KW or all OEM. And unless you plan on uping that rev limiter or switching out the HC2 for a more aggrissive cam then the OEM's should work well for ya.

Good luck!!

 

Ok, well my thinking on it is if I have to pull the head to replace spring then I'm going to replace the valves as well and go with KW. Next year I'll be dropping in a stroker crank and who knows what else. We have a trip planned for the Silver Lake sand dunes in mid April so that's why I'm in a hurry to figure out what's wrong. I'll be making another test run today with the valves on spec this time to see if that clears up the issues. I think my timing was off a tooth as well but I'm not certain because I've since removed the cam gear and put it back on. Would the quad fire up on the first kick if I was a tooth off on the timing? They are kinda a pain to set the timing while the motor is in the quad.

 

So I'm out on test ride 2 today and the culprit reared it's ugly head. The knocking was a blown head gasket with less than 10 minutes of ride time on it. Running the high comp that I'm running do I have other options for a head gasket? The gasket I have in it is brand new and should not have blown. I made sure I cleaned the surfaces and all before I put it on. Thankfully that's all it is, it runs awesome but I'm shutting it down and pulling the head. Looking forward to input on the gasket situations, thanks!

 

At 14:1 I've never had a head gasket problem.

Are you using an OEM gasket? Are you using any sort of copper spray adhesive?

 

You shouldn't have had any problems with an OEM or Cometic head gasket if it was new, but things happen...

When you take it apart, be sure to check that the gasket was the correct one, that you had all the dowels installed, and that the gasket had all the holes correctly punched in it for the water and oil passages. There have been a few cases of various passage holes misaligned or missing altogether.

If that is ok, I personally would have the head checked for warpage. If it ain't flat, it won't seal.

As far as gaskets go, I would install a new gasket without copper gasket spray, or a good used gasket with the copper spray, AFTER removing all the factory rubberlike coating from the gasket. But I would never install a new gasket with the factory coating AND copper spray together. Some peoples opinion might vary on the gasket deal, so take it for what it's worth...

Good luck, and let us know how it turns out.

Kris

 

Ripper has a Cometic he said he'd part with so I'm just going to buy that off him when I return his shim kit tonight (he's my HERO), the rivit came apart up front and allowed the gasket to seperate, I think this is what caused my issues, upsetting because it's so much work to tear it down and replace it since it was brand new but relieving that it's not something more serious.

I'm hoping it was just a fluke and I'll try my luck with a replacement gasket, if it goes again then I'll have the head checked for issues, hope not cuz I just had it ported and polished.

 

Got it all back together with the new head gasket and it's running again but now my exhaust valves are really loose, anyone have any ideas as to what would cause this? They were fine before the head gasket blew and I pulled it all apart.

 

Thanks for everything, it's running awesome now, I plan on taking her out in the woods tomorrow for some trail riding.

here's my Quad

 

Came across your post reading about some cam specs. I am having the same issue, on hard pulls quad runs hard untill about 3/4 to full throttle in 4th gear. I havent figured it out yet. Checking valves next.

For your issue was it the head gasket? Or vavles? Or combination of both?