I'm a few months off from starting this work but I'm boning up on my knowledge while it's raining today.

I'll be installing a FM 110" kit with BX heads on my cammed 103" this winter. I am a lifelong shade tree mechanic but mostly of the auto variety, I'm perfectly comfortable and capable of doing this work on my bike but I want to try to know what I don't know, you know?

I've been looking at this heat cycling recommendation from Zippers IMPORTANT (zippersperformance.com) as a starting point but thought I'd get some input for the Dyna forum. My main questions are:

• Oil recommendation for startup and break in
• Heat cycling phases/times/RPM/etc.
• Heat cycle by time or temp?
• Break in, 500/1000mi, 0mi? I've read it all it seems like

My bike is currently a cammed 2017 103" with ~6k miles on the clock. During the big bore install, the current cams will be replaced with Woods 777's. Bike already has a Feuling pump and will be getting a matching plate as well. S&S/FM adjustable pushrods, Woods lifters, ported/polished heads, bigger valves at10.5:1. I'm running a Thunderheader.

 

This one courtesy of HAMMER PERFORMANCE - High Performance for your Harley Twin Cam, Evo Big Twin, Sportster or Buell! 208-696-1250

 

And S&S via Cyril Huze S&S Cycle Tells You How To Break-In Your New Engine at Cyril Huze Post – Custom Motorcycle News (cyrilhuzeblog.com)

 

I've always used the S&S method to break in a engine and a fresh set of piston rings. Seems to work for me so far.

 

Built a couple ******/ Hammer engines. Their parts their rule, both engines have gone 20k+ miles trouble free. Only deviation was changing the Dino oil at 1,20, 50 and 100 miles but that's on me. Use liberal assembly lube and follow your parts companies instructions. They know their ****, usually.

 

Good topic and one that I also need to consider before my initial start up. Personally the break-in procedures wanting you to do 500-1000+ miles taking it easy and not going above 3500 or 4000 rpm are a bit absurd, your rings should be well seated within the first 100 miles...Quite literally that is the most important thing you are trying to accomplish during the break-in period and you cannot properly seat rings without the rings seeing the full spectrum of RPM they will see. I have a lot of experience breaking in 2 strokes but the principle is basically stroke for stroke, heat cycle, vary RPM, avoid hitting the limiter and being rough on the throttle and after the initial heat cycle period start cycling throttle to RPMs the motor will see in daily use.

Do your initial heat cycle as detailed in either of those guides.

Once you get to the point of actually riding the bike the first 50 miles take it easy as stated, do not hold any RPM range for too long and be easy rolling on and off the throttle still heat cycling as the the guides explain.

This is where my opinion starts to differ...

Change your oil and then from 50 - 100 miles continue varying RPM except I would break this down into steps. For instance 3x 15 mile increments, get out on the HWY or a good stretch of straight road and run the motor gently through it's RPM range. Occasionally bring it up to 5k and back off letting the bike decel on it's own power (no coasting) for 15 miles, stop and let bike cool down completely. Execute this procedure 2 more times and then change your oil again.

Now for the next 400 miles just ride like normal while continuing to be gentle on the throttle, smooth acceleration and deceleration. Don't be doing burn outs and dumb **** etc.

Change the oil/filter and you are done. If you want to continue taking it easy for the next 500 miles go for it but realistically the rings are seated by now so I don't see any point in it. Let her eat......

Edit:

• Oil recommendation for startup and break in - Kendall GT-1, Valvoline VR1 or your choice of brand. The old school guys will tell you to just run some straight 30w for those initial heat cycles cause you are just dumping that oil off, personally I am going to use cheap walmart oil for the initial heat cycles, Kendall for the first 50 and VR1 for the riding break-in mileage.
• Heat cycling phases/times/RPM/etc. - Same as the guides I've also head the old school guys say the same, as soon as she starts bring the idle up and hold it for the first minute or so and then your next heat cycles vary the RPM, just as the guides say.
• Heat cycle by time or temp? - Both but for temp you don't want the motor to get so hot you can't comfortably touch it.
• Break in, 500/1000mi, 0mi? I've read it all it seems like - See above
• I'm adding TUNING for you - Assuming you have a good base tune but if you didn't or don't know if you do waiting 500-1000 miles before getting the bike tuned COULD be detrimental to your engine. Some people choose to have it broken in on a dyno but that's $$. Personally I am going to get her tuned well before I hit the 500 mark.

Kevin Baxter has a good video explaining my opinion -

 

I basically followed steps 1-4 of the S&S break-in instructions. Then I trailered it to the shop that did the dyno tune, where they did some additional heat cycling then proceeded to do power pulls and tune. I picked it up from the dyno and let 'er rip. That was in 2017 and so far, so good. I don't recall how many 'miles' the dyno shop put on it while tuning, but I barely made it far enough from the shop for it to reach full operating temperature before it saw redline. I don't have enough will power to wait for 50 or 100 miles or any of that nonsense.

Some alternative logic that was referenced often back when I initially researched this. Some of which makes sense, the rest I have no idea.
http://www.mototuneusa.com/break_in_secrets.htm

 

Thanks for that info, much appreciated. Mind sharing who did your tune in the Cities?

 

If the OP has nearby access to a good tuner the new motor can be "broken in", i.e., good ring seal and tuned all in one session; done. One heat cycle for about a minute to listen for strange noises and leaks then off tot the dyno. Even if the bike has to be trailered to the dyno, one session and ride; just avoid stupid **** as has been said. Any good break in oil will do; I have had good luck with Shell Rotella 15W40. Dump oil and filter at 100 miles and again at 500 miles then change oil/filter at appropriate intervals.

 

Letting the dyno tuner break it in is definitely an option, just make sure they are renowned to some degree. Also I know a lot of people like to use Rotella in there bikes and for the initial run/heat cycles I am sure it is fine but long term use that oil isn't good for these engines because of the amount of detergents added for the excessively dirty environment diesels run into. It has a tendency to wash away the good carbon build up the motor needs to have.