Checked my valve clearances today!


18 replies to this topic
  • extex

Posted August 17, 2005 - 05:10 PM

#1

I bought the shims, gaskets, feelers, etc. and have been getting up the courage to check the clearances on my 05 WR450. I've got about 800 miles and it starts great with hardly any need for choke, runs great but I decided it was time. All valves within tolerance although on the tight side of the ranges but I decided to let them ride for now. I'll probably check them again after another 500 or so miles just to be sure but I sure was glad not to have to do the shimming.

One question I did have though was about the spark plug. This is the first time I have had the plug out (and hope I never have to change it on the trails) and it was really rusty which tells me water is getting in around the cap. I don't ride in severe water conditions so it must be from just washing. I don't use power washers. Is this common? Should I put some silicone or something around the seal?

  • dman450f

Posted August 17, 2005 - 05:15 PM

#2

I would like to know the answer to that one as well...

  • PBDBLUE

Posted August 17, 2005 - 05:52 PM

#3

Actually there is a drain hole in the side of the head that will allow water to get into the plug area when you wash the bike.

  • Dodjy

Posted August 17, 2005 - 06:18 PM

#4

Yep, I pulled the plug out the first time I washed the bike and wondered how the water got in until I found the hole (right side of the head). Now I just plug it with a plastic rod and the exhaust with a rubber bung before washing - no worries.

  • don319

Posted August 17, 2005 - 06:23 PM

#5

The hole is there to let the water out! But water gets in lower than the hole and causes the plug to corrode in. It is a good thing to check it occasionally, putting some high-temp never-seize on the plug threads.
Also, I have an '02 WR 426 with about 700-800 miles of trial riding. Change oil every 3rd ride. Valves still in spec! Gotta love those 5 valve heads!

  • don319

Posted August 17, 2005 - 06:25 PM

#6

Ooops! Should be TRAIL riding. Hard to ride trials on a 426..... Also, before removing the plug, take some compressed air and blow out the plug hole before pulling the plug.

  • Matty05

Posted August 17, 2005 - 06:26 PM

#7

The hole is there to let the water out! But water gets in lower than the hole and causes the plug to corrode in. It is a good thing to check it occasionally, putting some high-temp never-seize on the plug threads.
Also, I have an '02 WR 426 with about 700-800 miles of trial riding. Change oil every 3rd ride. Valves still in spec! Gotta love those 5 valve heads!

Yep, Yep and Yep :D

  • Indy_WR450

Posted August 17, 2005 - 06:40 PM

#8

A little rust around the nut is OK. There should be none on the threads.
Change the plug twice a year if you ride a lot. :D

  • FTD

Posted August 17, 2005 - 08:04 PM

#9

I am behind then. I haven't checked the valves in 2,200 miles. Starts great... runs awesome. :D
I did change the plug 100 miles ago... rusty old bastard :D
I rev that bike out on the trails, and she keeps purring!
No new bike for me... it may be heavy... but it's slow! :D

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  • toyota_mdt_tech

Posted August 17, 2005 - 08:19 PM

#10

Usualy, the water comes from the drain hole on the RH side of the bike cylinder head. And if you do wash it, water does go in there and on the kickstand (tils left) it holds some water in there. Dont seal anything. It will make it impossible to the evaporating water to exit, will condense and create more toruble then it solves. Just lots of water riding can get water into the plug well.

  • Joe_P

Posted August 17, 2005 - 08:20 PM

#11

Don't be afraid of checking valve clearances. Once you do it a couple of times, it becomes very simple. Here are some things I've learned and I'll pass them on along with my opinions on some things. Keep in mind that I'm a novice mechanic and I've made novice mistakes, but I still try to do as much wrenching on my bike as I can. Plus, my friends are very mechanically inclined, so they are often helping me with the procedures first time through and sometimes the second and third time also. I think that if you learn from my mistakes you'll have no problems. Now I can do a complete valve adjustment in ~3 hours.

Here it goes:
- Hopefully you have a repair manual. I bought the manual from Yamaha, but at the very least have a Clymer.

-Buy a set of shims from HotCams (or anyone else who sells shim kits). It's worth it for $100, especially if you're like me and you try to ride as much as possible. There is very little that could be more frustrating than checking the valves mid-week before a ride and finding out you have to order a shim. They are about the size of a pill, but they can ruin your weekend if you don't have one on hand. Your other option is to put the bike back together and ride while your part is on order, but then you have to go through the whole procedure all over again just for a tiny POS shim. Or you can ignore it all together, but then why would you go through the hassle if you're not going to adjust it anyway. I also think that you will be more apt to keep your clearances right in tolerance if you have them on hand. You won't be tempted to go a ride or two (or more) with them out of spec.

- I try to check my valves every 10 hours of operation. That's also when I change my oil, so it kind of goes hand in hand for me. As I'm letting the oil drain, I check the clearances. And 10 hours is good for me. I think that you can identify a trend if you keep half-decent notes of the adjustments you've made and possibly avoid some major expenses in the long run. I'd rather be certain that clearances are in spec as opposed to hoping they are. I also believe that every bike is a bit different and every rider (and riding style) is certainly different. If one guy has gone 1,000 miles without adjusting his valves, does that necessarily mean that you can or that your bike will? Don't forget that these are high-performance machines, not XR-600's.

- Be careful when pulling off the camshaft caps. There are circlips inserted in the bearing collars that can come off when you remove the caps if you're not careful. It's important not to drop them into the motor or lose them completely. When I first had to adjust the shims, I didn't pay attention to the schematic and never knew that those circlips were there. In the end, that caused me to not have the cams lined up properly when I tightened down the caps. I had to send my head out to Pro-Circuit to make sure that I didn't bend the caps.

-I replaced the intake cam without the circlip several times and ran the bike like that. Maybe I was lucky and had the cam lined up properly, but it was probably off by a little bit. Who knows what damage this caused. When installing the cams, look down into the head. There are two little notches machined where the bearing race sits. Basically, the cam bearings should be very close to touching those notches. Also make sure the lobes are centered over the buckets. Install the cam, install the circlip, install the caps. Don't use anything other than your hands to install the caps. If you can't get them on with your hands, then your alignment is off. Start over.

-Remember to fully retract the cam chain tensioner when you are installing it. At the time, I didn't have a screwdriver that would fit and I thought (for some unknown reason) re-tracting the tensioner wasn't a major step. Once things were back together, the chain was too tight to let the engine turn over. I believe this caused my chain to stretch out of spec and the only way to replace the cam chain is to remove the rotor...and believe me you don't want to go through that. But that's another story.

-When checking the timing, the lobes should point away from each other and there should be 13 pins in the cam chain between the punch marks on the cam sprockets.

- Use a magnet to remove the buckets. I spent about 20 minutes trying to remove an oily bucket with my hands one time. It can be done in a second with the magnet.

Those are the major things that I keep in mind when checking my clearances. Don't be afraid to do it, just take your time and consider it a part of your regular maintenance. I look at it as a price to be paid for the performance.

Good luck and hope this helped.

  • WheelsUp

Posted August 17, 2005 - 08:26 PM

#12

All valves within tolerance although on the tight side of the ranges but I decided to let them ride for now.

Tight is good. Remember, you can only get shims in .05 increments, and spec is .05mm wide, so if your intake measures 0.10, your next step would take it to 0.15... at the top end or "too loose".

Now... that's not 100% true :D

Your stock shims may very well be something like a 192, which means that if you buy a 190, you CAN move the clearance out by 0.02. This is actually what my buddy did with his. His center intake was at .07... just a little tight, and probably that way from the factory. Since the stock shims (in all valves) were 192, he switched to a 185 shim to move the center one to .14, and though the two outside valves are at .10, he went to 190 in those to bring them up to .12

I don't ride in severe water conditions so it must be from just washing. I don't use power washers. Is this common? Should I put some silicone or something around the seal?

Notice the little hole in the side of the head above the oil filter housing?
That allows water to drain from the spark plug hole. It also allows water to get in.
Plug it with a golf tee while washing, and after you warm the engine to dry it, lift the plug wire and blow some compressed air through there to make sure it's dry.

  • Joe_P

Posted August 17, 2005 - 08:27 PM

#13

Sorry, I see you did buy the shims :D Just take my reply as a general one. Sometimes it's difficult for me to get off my soapbox.

Thanks,
Joe

  • Joe_P

Posted August 17, 2005 - 08:33 PM

#14

I'm back. My attitude is that if they are in spec they are in spec. If Yamaha wanted them to be more precise then they would have made shims in increments of .025. Now, I also noticed that my HotCams kit fit both the Yamaha YZ/WR line and Honda CRF 450/250 line. I also read in one of the mags that Honda sells shims in .025 increments. So, buy a Honda shim for those in-between adjustments.

  • Mike Grady

Posted August 17, 2005 - 08:34 PM

#15

Just A note. My 05 WR450F has 1250 miles and I checked the valves and one exhaust valve was tight. Dealer shimmed it and starting is easier now. I will ride this weekend and see how she feels. Checking valves is critical. This was my thrid check the first two were ok. Tight valves can turn to burnt valves and rob you of power. Check them often.

Mike

  • extex

Posted August 18, 2005 - 02:34 AM

#16

I appreciate all the replies and the info on the spark plug rust. I always wondered what that little hole was for! I'm hoping to be one of the lucky ones and never have to shim but I will be checking regularly. It should be much easier next time although it wasn't bad the first time.

  • Indy_WR450

Posted August 18, 2005 - 03:42 AM

#17

I thought the circlip was necessary to keep the main bearing from walking off the cam shaft in the engine. I would recommend reinstalling the cam shaft cover with the half round retainers. :D

  • Joe_P

Posted August 18, 2005 - 07:09 AM

#18

The circlips could be used to both keep the cams aligned and keep the bearings from moving? Either way, the moral of the story is don't forget them like I did :D

  • farkawi

Posted August 18, 2005 - 08:13 AM

#19

I checked my valve clearance at 550mi out of paranoia. They are fine. Those rubber gaskets are miraculous and I can't see changing it until it gets stiff. Had a similar gasket on a street bike for over 50,000 miles and it never leaked. I too noted the crusties on the spark plug and have started using a plastic golf tee as a bung while washing. I also greased the linkage while servicing the bike and have figured out how to install grease fittings on the bearings. Yamaha should've done that for us!




 
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