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Znabb said:
I could not find the torque values for the crankshaft rotor bolt, clutch bolts or centrifugal oil filter nut in my workshop manual. Does anyone know these values or should i go "by feel"?
I just re-read this and it sounds a little condescending, sorry that was not my intention :?

Keep tightening till you strip the threads then back it off a tad :lol: :lol:

The rotor is held in place by the bolt, but secured by the taper and woodruff key so the torque required is only enough to stop the bolt from coming loose.

Ok, what torque is required for a given bolt or nut. Without getting complicated there are two basic types of nuts and bolts, type one, is for tension and type two is for shear loads.

Tension nuts/bolts are for holding something together with force, like head bolts/nuts, these require a greater force/torque to keep the assembly together and are generally stronger in tension but not brittle. I have seen con-rod bolts that have stretched but still maintained their integrity, these are tension bolts.

Shear bolts and nuts are (generally the bolt is the one enduring the shear loads) for holding an assembly together that has high shear loads and small tension loads, a good example is the bolts that hold the rear sprocket on the back wheel, high shear loads but low tension loads. You will generally notice that the nuts are thinner and mostly of a locking variety (Nylocks, nutlocks etc) and the heads smaller/thinner. These do not require the high torque loads to hold an assembly together so are made lighter and often from a different material.

Ok, what has that got to do with the torque required for a given nut/bolt, well you need to understand the application before deciding the torque used. Most web base torque charts list only values for tension bolts/nuts and this is an issue as these values may be to high for a shear nut/bolt and can cause damage or cause you to spill your beer :D

The torque value is also dependant on the material and application, but that's another story for another week, good night children :D :D :D

 

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Discussion Starter · #3 ·
Thanks for the info Rod! :D
You know that I always appreciate when you share your knowledge and I always learn something new.
The reason for me asking is that I usually always use my torque wrench and workshop manual when building engines. I have learned the hard way that my own thoughts on this matter don't always coincide with the constructors. :lol:
 

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Ronny,.... The springs themselves act as "lockwashers" by providing a pressure "bond" ...(remember how you had to "snap" break them loose?....)
 

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If you over-torqued you've smashed the head gasket more than usual - if you back off the torque, it may leak.
I have no idea what could happen if you leave them over-torqued.......

This is from the Honda FSM......

Capturez.JPG
 

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On some bikes, the extra torque can actually crack head.
CB450 isn't one of them though as head is a pretty massive casting.
It can stretch studs though or strip threads out of nuts.
If you haven't started motor you'll probably be OK backing off and re-torquing to max value (assuming you didn't go 50 ft/lbs over :p)
Until you get into hundreds of tons, the gasket will only 'squish' so far then stop (maybe even with a few hundred tons?
You could try sending a used gasket to the guys with the press on You Tube, it would be something useful for a change instead of crushing cans of silly string or red hot stuff :evil:
 

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Looks like some of these replies were meant for my post (http://www.hondatwins.net/forums/55...cb450k5-head-bolts-different-information.html) -- I had a spare set of gaskets, I replaced them anyways. They looked like they were in alright condition.

I would have gladly guinea-pigged it, but with the thermal expansion of the motor + unknown gasket crush, I wasn't willing to potentially warp the head.

Backing off and re-torquing would definitely have leaked, imo.
 
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