Torquing KOR Cylinder Head
- Thread starter Triple_B
- Start date
Yeah I just did this myself. On a KOR head.
Base nuts are 18, head are 20.
I just tightened them down to 20 off the bat. I go more than 1 sequence tho. Youll tighten the first one, then go through the series, get back to the first one, and it wont be at 20 no more, so youll hit it, click it to 20, go through the next ones, and they wont be.
I stop, when the all click in snug at 20 ft lbs on the head. Then I did my initial heat cycle part of my breakin per Kens instructions. Start it, get it idling, set a timer for 5 minutes or so, with a fan blowing on it if you can. Brap the throttle intermittently, dont let it sit at one RPM for long, brap, wind down, brap, brap, wind down. You get the picture. Shut it off. Let it cool down completely. Do this 3 times. Then tighten all your base and head studs. I had half of mine that had lessened and needed to be put back at 20.
Once I did my heat cycling, I rode it around a bit at different throttles, in different gears, put about a quarter tank of gas through it, topped off the gas with new premix (still same 32:1 yamalube r stuff Ive been using), and I started getting more aggressive with it.
The past couple days Ive been doing my jetting, so Ive been really hard on it. I figure its broken in. It isnt getting any more broken in than this, after a couple of days of ragging on it to get it jetted.
I took a compression reading on it, before I even started it for the first time, and it was at 125 (Im at 4500 ft elevation, it matters), and after my ride tomorrow, Ill take another one and see if Ive hurt it, or its gotten better or stayed the same.
Base nuts are 18, head are 20.
I just tightened them down to 20 off the bat. I go more than 1 sequence tho. Youll tighten the first one, then go through the series, get back to the first one, and it wont be at 20 no more, so youll hit it, click it to 20, go through the next ones, and they wont be.
I stop, when the all click in snug at 20 ft lbs on the head. Then I did my initial heat cycle part of my breakin per Kens instructions. Start it, get it idling, set a timer for 5 minutes or so, with a fan blowing on it if you can. Brap the throttle intermittently, dont let it sit at one RPM for long, brap, wind down, brap, brap, wind down. You get the picture. Shut it off. Let it cool down completely. Do this 3 times. Then tighten all your base and head studs. I had half of mine that had lessened and needed to be put back at 20.
Once I did my heat cycling, I rode it around a bit at different throttles, in different gears, put about a quarter tank of gas through it, topped off the gas with new premix (still same 32:1 yamalube r stuff Ive been using), and I started getting more aggressive with it.
The past couple days Ive been doing my jetting, so Ive been really hard on it. I figure its broken in. It isnt getting any more broken in than this, after a couple of days of ragging on it to get it jetted.
I took a compression reading on it, before I even started it for the first time, and it was at 125 (Im at 4500 ft elevation, it matters), and after my ride tomorrow, Ill take another one and see if Ive hurt it, or its gotten better or stayed the same.
