Heads up...on Head Bolt Reuse

[HV]

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I know HD recommends replacing Head Bolts when ever they are removed....seen a few that were Re Used ... here is what can Happen if you do

[rbabos]

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I know HD recommends replacing Head Bolts when ever they are removed....seen a few that were Re Used ... here is what can Happen if you do

Those look fairly new?  They weren't baked enough to bake the hydrogen embrittlement out from the plating process. A baking occurs naturally from engine heat over time.
Ron

[HV]

They were the second set that let go at a shop that re used them...they broke on the final TQ ....

[HD/Wrench]

Any the real question  is Do you really want that much tq on the bolt .  Being that I know for a fact one one bike that has had them on and off now 7+ times and just different tq procedure and slightly less final tq.  HD went larger and thinks ohh well bigger is better lets just add a increased tq .. 


Sorry but I disagree with HD on this set up ,   Not like its the only thing.. 

[VDeuce]

Timely, thanks!

[VDeuce]

Any the real question  is Do you really want that much tq on the bolt .  Being that I know for a fact one one bike that has had them on and off now 7+ times and just different tq procedure and slightly less final tq.  HD went larger and thinks ohh well bigger is better lets just add a increased tq .. 


Sorry but I disagree with HD on this set up ,   Not like its the only thing..

Steve and HV, what's your recommended torque procedure for these using Cometic gaskets? I've heard a final of 51 foot pounds.

[HV]

I havent done any Cometics yet on a M8 ..


Yes lowering the TQ would help them stop snapping off for sure

[VDeuce]

I havent done any Cometics yet on a M8 ..


Yes lowering the TQ would help them stop snapping off for sure

We used to set the Twin Cam's at 42 with Cometics. Wonder if I should shoot for perhaps 45...

Tried ordering those bolts, part number 10200303 - they are backordered from HD with no release date...

[rbabos]

I havent done any Cometics yet on a M8 ..


Yes lowering the TQ would help them stop snapping off for sure

We used to set the Twin Cam's at 42 with Cometics. Wonder if I should shoot for perhaps 45...

Tried ordering those bolts, part number 10200303 - they are backordered from HD with no release date...

Wow, unbelievable how some simple things are so hard to get.
Ron

[BigT]

I used Cometic M8 head gaskets and they included the same instructions for torque sequence and values as the Twin Cam. I looked in my manual and there is no mention of not reusing head bolts that I could find.

[1FSTRK]

I havent done any Cometics yet on a M8 ..


Yes lowering the TQ would help them stop snapping off for sure

We used to set the Twin Cam's at 42 with Cometics. Wonder if I should shoot for perhaps 45...

Tried ordering those bolts, part number 10200303 - they are backordered from HD with no release date...

Wow, unbelievable how some simple things are so hard to get.
Ron

Or I have seen the following happen:

WE have a problem with the last batches of bolts snapping and we will not be shipping any until we get to the bottom of why. We are tracking the the problem and all known good new bolts coming in are being used by the factory for new bike assembly.

[HV]

All stage Kits come with new Bolts....

[EL in NH]

All stage Kits come with new Bolts....

Do they change the studs as well?  I would have thought the studs would be more of a problem than the bolts . They would seem to be the more likely to stretch.

[VDeuce]

I havent done any Cometics yet on a M8 ..


Yes lowering the TQ would help them stop snapping off for sure

We used to set the Twin Cam's at 42 with Cometics. Wonder if I should shoot for perhaps 45...

Tried ordering those bolts, part number 10200303 - they are backordered from HD with no release date...

Wow, unbelievable how some simple things are so hard to get.
Ron

Or I have seen the following happen:

WE have a problem with the last batches of bolts snapping and we will not be shipping any until we get to the bottom of why. We are tracking the the problem and all known good new bolts coming in are being used by the factory for new bike assembly.

Did you go with those instructions? What was your final torque?

[HV]

Studs are not changed ...just the Bolts.....

[BVHOG]

A bigger diameter stud would require more torque to get the proper stretch. It seems more thread engagement would be the ticket for this problem

[VDeuce]

Walls of the new bolts don't seem any thicker than the TC bolts. Would have to measure.

[VDeuce]

I have been told by a reliable source 20, 35, 51 for Cometic gaskets. I have not tried yet.

[crewchief25H]

Here is a alternative to factory bolts

[Pete_Vit]

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I know HD recommends replacing Head Bolts when ever they are removed....seen a few that were Re Used ... here is what can Happen if you do

yup, seen that before  I replaced all my studs too, I know it's not necessary but I did anyway, I was on the final 35-40lb when mine busted loose, never got to the final 90* 

[BVHOG]

Does he have a website?

[crewchief25H]

Its in the works.

[SoZo]

Here is a alternative to factory bolts

This... ^^ or the Feuling (not as good but lie these reusable over and over) Final torque for me wit cometic was 45 with NO issues on my 120ci as per Feuling.

May try 51 on my next buid...

[turboprop]

Here is a alternative to factory bolts

This... ^^ or the Feuling (not as good but lie these reusable over and over) Final torque for me wit cometic was 45 with NO issues on my 120ci as per Feuling.

May try 51 on my next buid...

Neither Jims or Feuling make the head bolts they sell. They are made by ARP. Jims and Feuling head bolts are one and the same. The only difference is one is stainless and the other is black oxide. Same as ARP offers most every fastener they make.

[rbabos]

Likely reason for them snapping is from the plating process. Hydrogen embrittlement. There area ways to resolve this but looks like the step was missed. Baking is the usual treatment. Short answer, crap quality.
Ron