breaking in the motor

[russellsroost31]

hey guys i wanted to get some opinions of how to break in ur motor
i was told half throttle for a full tank of gas and then u can open her up but i just wanted to see what other people do to break it in

[hondaREX]

RING ITS NECK!!!! Seriously, but theres a real write up about this just search for it. Its in the popular 400ex thread links at the top of the 400ex section. Good luck

[TacicalRedneck]

I read somewhere the guy would let it heat up, then go crazy...... I took it easy on mine for the 1st tank of gas, the 2nd i was going a bit more wild, towards the end of the second i hit the rev limiter all the time.... Now i'm on the 3rd or 4th tank and shes still going. :chinese:

[CJM]

You only have a little bit of time to make the rings seal properly.

Basically let it warm up for 10 mins and beat the piss out of it varying the gears and throttle.

See the link in my sig for more info.

[BroEXwis]

Let her warm up, and ride it like its going to be rode in the future!!:D

[NacsMXer]

Originally posted by russellsroost31
hey guys i wanted to get some opinions of how to break in ur motor
i was told half throttle for a full tank of gas and then u can open her up but i just wanted to see what other people do to break it in

That's pretty much the wrong way to do it. If you have a new cam in there, you need to ride it for 30 minutes while constantly varying the RPM's. No idling, no steady throttle cruising. You basically want to accelerate, decelerate (engine braking), accelerate, decelerate, etc. This is crucial to breaking in a new cam.

You also want to ride it semi-aggressively. More on proper break-in here: http://www.mototuneusa.com/break_in_secrets.htm

[russellsroost31]

ok guys thanks for the tips
ill open her up to night and see what she can do

[chronicsmoke]

I read back pressure from engine braking helps seat them too, I cycled my 450 once or twice and then pounded it under load and heavy engine braking and have an abbusive 50hrs on those rings.

[russellsroost31]

all i have to say is wow
i cant beleive i didnt drop the piston and cams in sooner it has so much more topend and way better all around power and with the hmf it sounds amazing

[chronicsmoke]

Haha yah for sure, the first time I drove my 426 with a stage 2, I was expecting it to stop making power sooner in the rpm but it just keeps pulling. Surprises you at first lol.