HarleyTechTalk

I watch Kevin Baxter on youtube, the engine builder for Pro Twin performance (Skunkworks), and he was talking in on of his 128 build videos about a new headbolt torque sequence and torque spec that they developed with SnS.

https://youtu.be/KshqOOyaoKs

This seems quite interesting, and may be a good idea for M8 engines for longevity.
It seems 10->20->30->Back off 1/4th turn, wait 15min, then 45 ft lbs final torque.
He doesn't go over the exact procedure entirely, but there's enough info there to figure it out.

How different is this from the standard M8 headbolt torqueing proceedure.

I was thinking about getting a set of S&S headbolts and doing this, without removing the heads, just pull the bolts put the new ones in with the torque sequence and spec that he used.
I'm well aware that this stuff is probably largely irrelevant and pointless durability upgrade for a stage2 bike with a 55mm manifold. But I am replacing the rocker arms, and studs.
But whatever, the both are like 120$ and maybe I'll want stage 3 later on, who knows.

I probably wouldn't go through all of that just to try a new process or torque sequence. If it's sealed up good already and your not pulling your heads then I would say don't worry about it. I also wouldn't take the head bolts out to replace them with S&S without replacing the head gaskets to. I'm not a professional or pretend to be so maybe someone smarter than me would say better.

Aye fair enough.

I'm still going to replace the rockershafts and studs though. No reason not too since they're not much work at all.

Quote from: FranBunnyFFXII on June 21, 2022, 10:09:06 PMI watch Kevin Baxter on youtube, the engine builder for Pro Twin performance (Skunkworks), and he was talking in on of his 128 build videos about a new headbolt torque sequence and torque spec that they developed with SnS.

https://youtu.be/KshqOOyaoKs

This seems quite interesting, and may be a good idea for M8 engines for longevity.
It seems 10->20->30->Back off 1/4th turn, wait 15min, then 45 ft lbs final torque.
He doesn't go over the exact procedure entirely, but there's enough info there to figure it out.

How different is this from the standard M8 headbolt torqueing proceedure.

I was thinking about getting a set of S&S headbolts and doing this, without removing the heads, just pull the bolts put the new ones in with the torque sequence and spec that he used.
I'm well aware that this stuff is probably largely irrelevant and pointless durability upgrade for a stage2 bike with a 55mm manifold. But I am replacing the rocker arms, and studs.
But whatever, the both are like 120$ and maybe I'll want stage 3 later on, who knows.

He seems to be using S&S torque sequence, which has been around for a couple of years.


https://www.sscycle.com/docs/default-source/instruction-sheets/510-0662-m8-headbolts.pdf?sfvrsn=2

If you're planning a stage 3 down the road. Wouldn't THAT be the best time to change head bolts. And in fact you SHOULD replace the head bolts on an M8. The OEM bolts are use once and replace.

You guys are no fun and are messing this all up. What a great opportunity to have some fun.

OP - Yes, definitely yes, change those head bolts. This is critical. Don't delay.

Oh, you should also probably start anther thread to discuss what type and how much grease (if any) should be used under the heads and on the threads of these new head bolts.

Dont forget wear rubber gloves and to take lots of pictures.

These threads are worthless without good pictures.

Quote from: turboprop on June 22, 2022, 10:27:31 AMYou guys are no fun and are messing this all up. What a great opportunity to have some fun.

OP - Yes, definitely yes, change those head bolts. This is critical. Don't delay.

Oh, you should also probably start anther thread to discuss what type and how much grease (if any) should be used under the heads and on the threads of these new head bolts.

Dont forget wear rubber gloves and to take lots of pictures.

These threads are worthless without good pictures.

Glad you're having fun.

It was just a question, an inquiry.

This is the grease I use under my head bolts. Rigidthumper made me waste more money for this high tech grease!   works great. And rubber gloves are for wussies

   That's the stuff.