2008 WR450 Head Bolts Do you follow the Manual????

So I took my head off to send away for "work"..

I was going over the re-install in the manual..

Step 1-Install the head bolts in the cross patten to 22ft lbs

Step 2- Undo all head bolts,remove, re lube and torque to 14 ft lbs stop,make marks then turn bolt another 180 degrees from marks.

Does anyone else follow this procedure??

I must say it took everything I had to loosen the head bolts and my bike is new and spotless with no grime or rust/oxy on the bolts.No way did that feel like 14ft lbs plus a 180 turn extra.

Next the rear head bolt on the outer "dry" left side of the motor won't even lift out of the head till you have all three others out so you can slightly twist the head to clear the frame-it will not just pull vertically out like the others.

There is no way with the engine in the bike I could get the head torqued down THEN re-remove the head bolts and lube the required 2nd time with out taking the head off the cylinder.

All the big bore kit install videos the guy just torques the head down to "spec".

Well...Yamaha "spec" calls for this double procedure..

ThumperTalk Yamaha Community-

What say Ye??

Edited by ILOAD2
title

30 views and no one has an opinion on the manuals guidelines???

Im looking at the 1 or 2 videos online that show a head being installed and theses guys are saying a simple torque of the head bolts to 27ft pounds is all you do??

That is clearly NOT what Yamaha is saying?

Anyone here ever re install a WR450 head themselves?

I follow the manual...

Follow what the manual says. 14 ftlbs plus half a round is actually pretty tight especially when you precrush the gasket in the first step.

How did you guys remove the right hand side,rear head bolt and clear the frame spar? did you have the motor out of the frame?

Just to remove the head I had to take the other 3 out, pop the head and turn it slightly to clear that fourth bolt?

If I snug it down to 22ft lbs-It would defeat the whole purpose of pre-crushing if I had to pop the head to remove and grease that fourth bolt.

As soon as you break the bolts loose all the tension is gone, the weight of the head makes no real difference.

You could also follow procedure, pick the bolt up and let a few drops of oil run down the shank of the bolt. That will lube them fine, just don't go more than a couple of drops. cause too much will hydrolock the bolt and break it off.

So I took my head off to send away for "work"..

I was going over the re-install in the manual..

Step 1-Install the head bolts in the cross patten to 22ft lbs

Step 2- Undo all head bolts,remove, re lube and torque to 14 ft lbs stop,make marks then turn bolt another 180 degrees from marks.

Does anyone else follow this procedure??

Yes, that's the procedure, alright. It's referred to as "angle torquing" and has come into general use throughout the automotive industry. This link explains:

http://www.thumpertalk.com/forum/showthread.php?t=972816

As far as re-removing the bolts for the second application of the thread lube with the engine in the frame, I don't, only because in order to do that with the aluminum frame, you need to disturb the head gasket what I consider an excessive amount. But I do slack them off and reset them to the lighter torque for the final run down. Be sure you do the 180 degrees 90 at a time, as prescribed.

Yes, that's the procedure, alright. It's referred to as "angle torquing" and has come into general use throughout the automotive industry. This link explains:

http://www.thumpertalk.com/forum/showthread.php?t=972816

As far as re-removing the bolts for the second application of the thread lube with the engine in the frame, I don't, only because in order to do that with the aluminum frame, you need to disturb the head gasket what I consider an excessive amount. But I do slack them off and reset them to the lighter torque for the final run down. Be sure you do the 180 degrees 90 at a time, as prescribed.

Gray- Thank you for you're reply and link. I searched and searched before posting.The link that you posted had all the information I needed. I used every wording I could think of EXCEPT "tighten"..That's why the thread never came up in my searches..Sounds like you know exactly the case of that 4th bolt not clearing the frame spar.:smirk: and what it takes to twist the head slightly to get it.My course of action is set when my Head comes back from the Laboratory .

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