Its a 98 400 Explorer
I just did the top end. New Wiseco Piston and Bored cylinder.
Carbs rebuilt. I believe I have it all set per the manual. Throttle cable adjusted. Oil pump adjusted. New Drive belt and all the plastic is back on.
It starts right up and Idles with out the use of the Choke. Idles ok, Don't have a tac to tell if its right or not. I read I'm suppose to run around at 1/3 throttle for 100 hours????????? That would take me till 2010.
Seems nothing you buy anymore needs this Break in period.
I have also read other people say they don't believe this break in thing and to drive it like you stole it for the first 100 hour.
What do yall think. I did give it a couple of Good squirts down the driveway and this thing will Git.

 

I always go with the recommended break in period but most of my buddies subscribe to the drive it like ya stole it.....and i really belive we are probably about the same in maintenance.........i think you should give a little to "seat" everything but thats just me

 

best way to break it in is to not run WOT but dont putt putt around. dont hold the rpms at a steady pace. always be moving the throttle faster and slower. run a 50:1 mix gas along with the oil pump for the first tank. everything requires a little bit extra oil because of the extra friction/heat from a fresh bore. with a bigger bore its not a bad idea to add an ounce or two of oil to every tank of gas becuase of the larger surface area. i know theres not much more surface area but it doesnt hurt.

 

BEAT THE CRAP OUT OF IT!!Vary the RPM's but beat it to death!The recommended breakin will lose you power in the long run.

 

WOOOO HOOOOOOOOOO
HAHA
The funny thing was today I was at the Owners Garage, This Thing actually belongs to his wife. Shes also the book keeper there. anyhow I told her, Hey I got your ATV running, (its been sittin in his shop for 2 year not running) anyhow she got real excited and asked when she would get it. I said ...Well I still have to break it in.
She told me she could break it in and I told her No, there is a very specific way to do it and I would hate for you to Blow the motor and loose the grand you have in it up till now. So I'll get her broke in for ya . HEHE.
I got a good 100 hour of fun set up for this thing LOL
THanks

 

Run for 10 min let cool for 10 min. Run for 20 min let cool for 20 min. Run for 30 min let cool for 30 min. And there you have it. Run the first tank with 50/1 along with the injection. Good luck