Back off 1/4 or no on head retorque

[trippivot]

these engines were all run and heated up BEFORE they ever were installed into the frame. filled and drained of oil. yes re-torqued after heat cycle

this is my air cooled procedure. not for for liquid cooled engines.

I do not loosen and retorque - unless there is a specific instruction to do so- and I can not remember when. ANY compression sealing problem and it usually leads to taking the head back off. oil leaks are expected with copper gaskets head or base.

1 wave finger tight
2 wave 10 - 15 lb/ft
3 wave 25 30 lb / ft
4 wave final torque spec. and depending on the stud mfg. 35, 38, 40, 42? arp lube if necessary.

heat up completely and let fully cool - re torque to final torque spec. just to check if any nut/bolt takes a little more to get tight. I re-torque all the 6X1 case cover bolts too.

[49er]

bad valves and failing valve rocker assemblies mainly. plus the odd piston failure. th first v4 750's were in every week lol

Some of the early Honda OHC singles had oil feed problems to the cam bearings too, or were their clearances just too close.

[Agemax]

these engines were all run and heated up BEFORE they ever were installed into the frame. filled and drained of oil. yes re-torqued after heat cycle

this is my air cooled procedure. not for for liquid cooled engines.

I do not loosen and retorque - unless there is a specific instruction to do so- and I can not remember when. ANY compression sealing problem and it usually leads to taking the head back off. oil leaks are expected with copper gaskets head or base.

1 wave finger tight
2 wave 10 - 15 lb/ft
3 wave 25 30 lb / ft
4 wave final torque spec. and depending on the stud mfg. 35, 38, 40, 42? arp lube if necessary.

heat up completely and let fully cool - re torque to final torque spec. just to check if any nut/bolt takes a little more to get tight. I re-torque all the 6X1 case cover bolts too.

no they are not. they come off the production line ready built and as stated before bolted up by pneumatic guns to a preset torque, and thats how they stay till they leave the factory into your nearest showroom.
i know i have been to the honda factory and seen it in action

[salty_monk]

A lot of the European cars have this "set rotation" fastening guide for torque. Some even specify a low torque value with a, then rotate 90 degrees plus or something similar.

Dan

[TheCafeKid]

ok, You guys are NERDS! I look at it this way.. Incremental initial torque of the head nuts. As perscribed and what ive learned in my short years of wrenching. Makes sense. Common sense. If it doesnt, dont wrench on it.. anyway, 3-500 miles in, recheck. Now, I made a mistake on the last motor i rebuilt (sorry MRiddle..i still want to fix it damnit, and wish you'd let me! :P ) but that was a ring alignment problem. My fault. BUT, between Steve and I, Ive put quite a few STREET GOING GS motors back together and never once had a problem with a head gasket leak. Vesrah, Cometic (sucks) Athena, whatever.. their orings leak, but the gasket itself? Meh. Now, Im not building high comp, extra heavy HP race motors, so I dont know what im talking about there, but, without going into the insane physics, thermal dynamics, and friction loads, etc etc, it seems to make sense to torque incrementally, recheck later, and torque as necessary. Ive never gone into it this much, and as such, it certainly makes it sound more complex than in my lay opinion, it needs to be for a friggin street bike. If it was blueprinted, sure, but even in the tight confines of Suzuki's design, it sounds like splitting hairs...

And BTW, you have it mixed up: In light spectrum, WHITE is the combination of ALL colours of the spectrum. Black is the absense of all colours, or all light, period.
In pigment, white is ZERO colour, and black is EVERY colour...

[Agemax]

ok, You guys are NERDS! I look at it this way.. Incremental initial torque of the head nuts. As perscribed and what ive learned in my short years of wrenching. Makes sense. Common sense. If it doesnt, dont wrench on it.. anyway, 3-500 miles in, recheck. Now, I made a mistake on the last motor i rebuilt (sorry MRiddle..i still want to fix it damnit, and wish you'd let me! :P ) but that was a ring alignment problem. My fault. BUT, between Steve and I, Ive put quite a few STREET GOING GS motors back together and never once had a problem with a head gasket leak. Vesrah, Cometic (sucks) Athena, whatever.. their orings leak, but the gasket itself? Meh. Now, Im not building high comp, extra heavy HP race motors, so I dont know what im talking about there, but, without going into the insane physics, thermal dynamics, and friction loads, etc etc, it seems to make sense to torque incrementally, recheck later, and torque as necessary. Ive never gone into it this much, and as such, it certainly makes it sound more complex than in my lay opinion, it needs to be for a friggin street bike. If it was blueprinted, sure, but even in the tight confines of Suzuki's design, it sounds like splitting hairs...

And BTW, you have it mixed up: In light spectrum, WHITE is the combination of ALL colours of the spectrum. Black is the absense of all colours, or all light, period.
In pigment, white is ZERO colour, and black is EVERY colour...

and you are the best motorcycle mechanic ever to grace gods earth?

[TheCafeKid]

and you are the best motorcycle mechanic ever to grace gods earth?

Well. Yeah! Duh!

[Nessism]

i worked for honda in the 80's and not one service involved a head retorque. even any engine that blew for what ever reason that came in for a rebuild was not required to come in for a head retorque to guarantee their warranty on the engine rebuild

The Suzuki GS engines are some of the most durable from the period and Suzuki recommends re-torquing the head at 600 miles and then every time the valves are adjusted. Is it necessary? Maybe not but it certainly doesn't hurt.

With regards to what manufacturers do inside the factory, you guys don't know other maybe what someone saw inside one factory so please don't claim to know what happens industry wide.

[posplayr]

Blissful ignorance ZONE:

******* DO NOT PROCEED BEyOND THIS POINT ************

real world

[tejasmud]

Nerds?

Real World.



This stuff is cool. I have worked with it looking at gasketed surfaces and force measurement. Expensive, but fun to play with.

http://www.sensorprod.com/pressurex.php

.

[doctorgonzo]

Man, all I did was a ask a simple question... the next thing you know it's a mechanical engineer nerd fest!

[Agemax]

Well. Yeah! Duh!

HAHA , arent we all?

[rapidray]

and you are the best motorcycle mechanic ever to grace gods earth?

No, I am!!! LOL!!! Ray.

[49er]

Shame to let a perfectly good thread die like this.

A question for the drag racers.

At what CR do you decide to fit larger studs and how much increase in torque on the nuts do you go to?

Does the increase in torque and heat generated on a high output air cooled engine affect the amount of natural expansion and cause some crushing of the aluminium cylinder surfaces? If so, how do you combat this?

[rapidray]

I put the APE studs in ALL of the motors I have because once you start leaning on them the stock studs will give some. I would deem them mandatory on anything 12.0 to 1 or more but that is just me & I overbuild everything! Ray.