Ready to go back to stock EX Cam!!! Help please.


95 replies to this topic
  • Indy_WR450

Posted December 01, 2005 - 12:39 PM

#21

I am not sure you want to pull the head unless you think you bent a valve by running it for a short time with the hot cams cam! These valves are easy to bend if your hot cam was not timed right. :applause:

  • jbrooks26

Posted December 01, 2005 - 01:00 PM

#22

I think I am going to pull both cams and check for compression. If I don't notice a difference then Is there an alternative to pulling the head? Like I said, I don't think I have bent any valves, but how can you be sure. I do know that I can push all of the valves and they are free. I just am not sure of where to go from here.

  • troys450

Posted December 01, 2005 - 08:43 PM

#23

this really sounds like big vacuum leak.you didnt say whether you had the carb or intake off,but check with carb cleaner in thru the airbox while its running.if its lean from a leak itll rev up alot.then spray around til you find the leak[s].good luck

  • devo1

Posted December 02, 2005 - 06:21 AM

#24

Josh, I think it's just a timing issue. Do a search for Auto Decompression Upgrade and find the picture of the cam lobes. If you're at your wit's end, bring your bike to my shop and we'll open mine up and compare. I'm about 2-1/2 - 3 hours from you.

later, Devo

  • Indy_WR450

Posted December 02, 2005 - 10:32 AM

#25

Devo to the rescue! :ride: Have not seen Devo on the forum much but we all had a blast in the Ozarks this fall. :applause:
I am sure hope it is just timing. The Ti valves bend so easily from kissing the piston if you had a defective timing hot cam in there for even a short idle. :p

  • Indy_WR450

Posted December 02, 2005 - 07:27 PM

#26

I found that on the CRF450 forum "KMan" gave up on the Hot cams and went back to stock cam with sucess!

Kman says:

I was wrong it was not a stage three it was in fact a stage 2. I am reinstalling the stock cam and having the ports cleaned up. It was started last night with no problem. I will send the cam back and have Hot cams take a look at it. My mechanic suggested a high compression piston as the next mod if I want a little more sumtin sumtin. Can't say that I didn't try.

  • jbrooks26

Posted December 02, 2005 - 07:58 PM

#27

Ok guys, let's forget about the timing for just a little while. I do think that I may have had the timing messed up when I originally installed the Hotcams cam. However, my main concern right now is that I have the stock cam re-installed and I can kick it over without using the manual decomp lever. I have not tried to get it started this way, I didn't want to do any more damage than may already be done. Is there any way to tell if I have bent a valve without pulling the head? If I pull the head, are there any tools I will need, or any gotcha's that I should know about? After I get this compression issue figured out I will get back on the cam issue. I know that I did not have the Hotcams installed more than 1 tooth off in either direction, but I was counting pins as well as using the timing marks. Would this have been enough to bend a valve during the break in ride? Thanks,

Josh

  • Indy_WR450

Posted December 02, 2005 - 11:53 PM

#28

Oh Yeah you most likely have bent a valve enough to reduce the compression if the clearances are in spec. You have to pull the head off to inspect them and replace them. That is the only damage that makes sense why you lost compression trying to going back to the stock cam. :applause:

  • Ticeman

Posted December 03, 2005 - 04:24 AM

#29

From what you are describing you may have dislodged one of the shims. Have you checked your valve clearances since the reinstall of your stock cam? Did you happen to lift the buckets out of the head when you removed the stock cam the first time?

This is the problem with listening to people that haven't got a clue, they just want to start sh!t by saying the cam is bad right off the bat. I have no idea what Indy450's problem with Hot Cams is and I don't care but, he's not offering solutions just saying the cam is bad. The gears are NOT bolted to the shaft, they are pressed onto the camshaft.

I've seen so many HONDA CRF450 cams damaged by consumers not knowing how to install the cam, it's sickening. These two engines couldn't be any more different but they still have the same problems, the installer not knowing what to look for or what he's doing when he puts it together. It's exceedingly easy to botch an install in many different ways. Especially if it's your first try.

  • jbrooks26

Posted December 03, 2005 - 05:31 AM

#30

Maybe before you start assuming that people "dont have a clue" you should read the whole thread and do a little research on what is going on. Indy has one of the most respected opinions on TT and if you spent a little time here you would realize that. That aside, if you had completely read this thread you would also know that I have reshimmed the valves both when I went to the hotcams, and also when I went back to stock. I am 100% positive that they are within spec. I have checked clearances more times than I can count. I don't really see how a shim could become dislodged if it had been installed properly, they fit pretty tightly into the valve keeper body, and the clearances are much less than the thickness of the shims I am using. Have you seen this before???

Can anyone tell me what I need to do to remove this head? Anything to be careful about? Helpful tips to make it easier, or special tools that will be needed??? Thanks,

Josh

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  • Birdie426

Posted December 03, 2005 - 09:52 AM

#31

Ok guys, let's forget about the timing for just a little while. I do think that I may have had the timing messed up when I originally installed the Hotcams cam. However, my main concern right now is that I have the stock cam re-installed and I can kick it over without using the manual decomp lever. ....... I know that I did not have the Hotcams installed more than 1 tooth off in either direction, but I was counting pins as well as using the timing marks. Would this have been enough to bend a valve during the break in ride? Thanks,

Josh


Josh-
Timing of the Hot Cams is neither "YZ" nor "WR", so pins are really irrelevant. It's the timing marks that matter. I have both intake and exhaust hot cams on my 426. The intake cam has an adjustable sprocket, and you don't have to move it very far for that center intake valve to kiss the piston. When I installed mine, I pulled the head and did the clay on top of the piston test to be sure I had adequate clearance, and with all set up, there isn't much. In other words, if you were off one tooth on timing, you have likely bent a valve.

It's easy to get the head off with the engine in t he frame. I would be really careful about trying to do a "normal" compression test without the cams installed. That cam chain will get balled up around the crank shaft gear and either bend the chain or bend a tooth on the sprocket. Try to rig up something similar to a bottom end compresion test on a two smoke. That is, a tee'd gage set up that will allow you to pressurize the cylinder with compressed air (I'd use a bicycle pump so you don't blow out a bunch of seals and gaskets), up to about 100 psi, then watch for leak down.

For what it's worth, I don't know why Indy is so down on hot cams. I love my set up (intake and exhausts, Wiseco 13.5:1 piston), and found the hot cams folks to be easy to deal with and most helpful.

Birdie

  • Ticeman

Posted December 03, 2005 - 10:57 AM

#32

Indy disliking Hot Cams and being a respected member aside, where does it stand right now? Have you done a leak down test? Have you tried a compression test with the decompressor weight in the outward position?

  • jbrooks26

Posted December 03, 2005 - 06:03 PM

#33

I don't thik that Indy dislikes hotcams, as far as I know he doesn't run them. He simply noticed what I had noticed and several others had also taken notice to a high number of people having similar problems with the hotcams product lately. Anyway, that doesn't really matter now.

To answer your questions, I have not done any compression testing and I don't have the equipment to do that. However, I know that I have lost compression for some reason just because with the bike timed properly with the stock equipment I can kick through the compression stroke without releasing the compression. I suspect a bent exhaust valve because I have not touched the intake side. I also suspect that the cause was my poor understanding of the hotcams product and not the product itself. I am hitting a busy spell in my life right now and will probably not get a chance to pull the head right away but I will keep everyone updated. Thanks to all who have provided advice, and if there is any more, keep it coming.

Josh

  • jbrooks26

Posted December 04, 2005 - 09:35 AM

#34

Indy disliking Hot Cams and being a respected member aside, where does it stand right now? Have you done a leak down test? Have you tried a compression test with the decompressor weight in the outward position?



What do you mean by "decompressor weight in the outward position"? I don't guess I know what that is. Thanks,

Josh

  • CRFThumper

Posted December 04, 2005 - 10:16 AM

#35

OK,I'm getting in to this a little late but,I would think you would know if you bent a valve!Either by sound or by feeling it while kicking it over for the first time!At this point if it were here with me I would do as you stated and pull the cams and check for comp.I have seen shims get put in cocked and cause problems but if you are sure the valves are in spec then that cant be it.You said you could push the valves down,do they all feel normal as in the same as the other ones?Everybody is right when saying that the stems are easy to bend,however I would do everything possible to avoid pulling the head.

  • jbrooks26

Posted December 04, 2005 - 01:01 PM

#36

OK,I'm getting in to this a little late but,I would think you would know if you bent a valve!Either by sound or by feeling it while kicking it over for the first time!At this point if it were here with me I would do as you stated and pull the cams and check for comp.I have seen shims get put in cocked and cause problems but if you are sure the valves are in spec then that cant be it.You said you could push the valves down,do they all feel normal as in the same as the other ones?Everybody is right when saying that the stems are easy to bend,however I would do everything possible to avoid pulling the head.


This is what I thought as well, that I would have known. But the further I go with it the more I think that this is the only possibility right now. All of the valves are within spec as stated, I have not done anything to the intake side, and I think that I had the hotcam in out of time the first time I started it. I can push them all and they all seem smooth. I have not lost all compression, but it is not what it should be either. I never heard any noises, and I never felt anything out of the norm when turning it over by hand with a socket. I can hear a hissing noise now when turning it over by hand when the compression stroke nears the top. I could hear this to some extent before also, but I had to pull the decomp lever to get the timing mark to line up in the sight hole. The deeper I dig, the more clearly it seems to be a valve problem.

I have a few people telling me to avoid pulling the head at all costs, and a few that tell me that it is no big deal. Why would it be bad to pull the head? Thanks,

Josh

  • Indy_WR450

Posted December 04, 2005 - 01:42 PM

#37

Yes pull the head and make sure you keep the cam chain up tight around the crank sprocket and tied to the frame during the procedure and after. You may want and extra hand as you pull the head out.

  • StreetbikePimp

Posted December 04, 2005 - 01:50 PM

#38

jbrooks,

We don't know why...but you don't have any compression. Could be a bent valve, bad timing, poor valve seating, or it could be bad rings...it's anybodys guess right now.

You need to perform a leak-down test to tell where the problem is. Exhaust valves, Intake valves, or Rings.

Either do a search for "leak down test" and buy the equipment to do it yourself, or take it to a dealer and have them do it and tell you what the results are. Should be no longer then a 1/2 hour of shop time.

  • CRFThumper

Posted December 05, 2005 - 04:13 AM

#39

This is what I thought as well, that I would have known. But the further I go with it the more I think that this is the only possibility right now. All of the valves are within spec as stated, I have not done anything to the intake side, and I think that I had the hotcam in out of time the first time I started it. I can push them all and they all seem smooth. I have not lost all compression, but it is not what it should be either. I never heard any noises, and I never felt anything out of the norm when turning it over by hand with a socket. I can hear a hissing noise now when turning it over by hand when the compression stroke nears the top. I could hear this to some extent before also, but I had to pull the decomp lever to get the timing mark to line up in the sight hole. The deeper I dig, the more clearly it seems to be a valve problem.

I have a few people telling me to avoid pulling the head at all costs, and a few that tell me that it is no big deal. Why would it be bad to pull the head? Thanks,

Josh




Its not that it is a bad thing,it's just time and gaskets.As easy as it is to get a tooth out of time,I just think it is a timing or shim problem!
Maybe I'm as wrong as can be and I know you don't want too hear it again but start there again!Did you pull the cams to check for comp?If you have to pull the head then pull it ,not a big deal head gasket and some copper washers andyou are good to go.Indy is rite watch the cam chain!

  • jbrooks26

Posted December 05, 2005 - 01:33 PM

#40

Its not that it is a bad thing,it's just time and gaskets.As easy as it is to get a tooth out of time,I just think it is a timing or shim problem!
Maybe I'm as wrong as can be and I know you don't want too hear it again but start there again!Did you pull the cams to check for comp?If you have to pull the head then pull it ,not a big deal head gasket and some copper washers andyou are good to go.Indy is rite watch the cam chain!


I am 100% positive that the timing is correct. I have checked it about 15 or 20 times throughout this whole process both with the stock cam and the Hotcam. Also, the clearances have been checked every time I have had the valve cover off. I truly believe it is time to move forward with this. I don't have a way to get on the rearward center cam bolt for the intake cam with a torque wrench yet, I need a wobble socket or a crows foot or something like it. My torque wrench won't fit between the frame and the bolt. Anyway, I am not too concerned about that right now, I am planning on doing the leak down test before I go any further, but I have to get the equipment first. I have clearance on both cams at TDC so I should be able to run this test without any problems. Hopefully this will tell me something. Thanks,

Josh




 
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