This normal?

[luvmyex]

After i rebuilt my engine i broke a head bolt off and had to take it back apart.Well i went ahead and did my 20min break in ride.When i took it apart to get the bolt out, my piston had a black spot about the size of a silver dollar.It wiped right off but.I know it will get black but should it do it that fast?Normal or not?Or am i running to rich?Im set with a 158 main42 pilot clip down one notch from stock.Air screw about 3 1/4 turns out. Im also getting a small amount of black smoke from the pipe when i blip the throttle.

[Castor-426ex]

i was told to jet fat upon initial break in..but i dont understand what is causing that on yours...hows it running?

[luvmyex]

Well ive only rode it for the 20 mins.And i havent been over half throttle.I didnt fast rev but i did get to 5th gear 3-4 times.It seemed to run fine.And the plug was new it was a little black but the center was still white.thats after it all cooled down.I didnt check it hot.

[speedjunkie]

You got to be running rich. Iwould just leave it that way until break-in is over. After it is broken in you can push it harder and see what needs to be done jets wise. I run a 160 main and live at 2,500 feet. Sounds to me like it could be the idle circuit thats a little fat. Hope I helped!?!

[luvmyex]

Ok but if it stays rich what do i need to do?And does the air screw how anything to do with beeing rich or lean?

[YZROOSTINYA]

dont go into 5th on break in

its no biggie

prob a litle rich

155 is where i am at 2 1/2 turns out

4th clip down 42 pilot

i just read a dirt wheels issue that said you should run ur quad at 1/4 throttle, 1-5 gear 20 minutes at a time. Let it cool down to the touch and then ride again for 20 minutes do this 5 or 6 times then change the oil and do it all over again. Why shouldn't u hit 5th in a break in???

[Castor-426ex]

mainly to not lug the engine because you arent suppose to go hard on the throttle on break in