engine break in, cant seem to find any when i searched?

[400exmxrider15]

Just got my 400ex back from the mechanic after a long months top end overhaul and other numerous little things. Can someone tell me what the best 'break-in' method? Mechanic said to ride no more than half throttle and not to put it underload for the first tank of gas....

[CJM]

Every single atv ive built up or got I used this method and it works. many others here used it too with great success.

http://www.mototuneusa.com/break_in_secrets.htm

basically warm it up and beat the crap out of it-you want the rings to seal well to the cylinder.

[irondaddy44]

i have heard some people ride it as hard as they can. i know there is a web site where a guy that builds race bikes breaks all his bike in this way. just what i heard.

[400exmxrider15]

hmmm... I hate to beat the hell out of it!!! I dont wanna take a chance of burning it up....

[CJM]

Originally posted by 400exmxrider15
hmmm... I hate to beat the hell out of it!!! I dont wanna take a chance of burning it up....

if you dont ride it the way outlined the rings may not seat properly-then you gotta hone the cylinder and re-ring it.

Look at it like this: I built my quad some 3 years ago. I put it all together, warmed it up then did pretty much EXACTLY what that site I linked outlines. I havent burned a drop of oil, overheated, blown a gasket or anything and I must have over 400 hours on it by now.

If you were to have someone building an engine for a car at a performance shop they take that engine when fully assembled and do whats called a break in before they even give it to you to check for issues. They hook up the engine out of the vehicle and run it pretty much exactly how motoman does.

Like I said, reason for all of this is to seat the rings to the cylinder well.

[honda400ex2003]

Originally posted by CJM
Every single atv ive built up or got I used this method and it works. many others here used it too with great success.

http://www.mototuneusa.com/break_in_secrets.htm

basically warm it up and beat the crap out of it-you want the rings to seal well to the cylinder.

that one gets my vote. I didnt do just 3 sets though, i did it till i could feel it was finished breaking in. It doesnt always take only 3 warmups and cool downs but the mx style riding is where its at for sure.

:D steve

[CJM]

I did mine on the street, mildly breaking it in by getting on and off the throttle for about 20 mins. Then took it out for the day and that was that :)

[Thumpin440ex]

Warm it up a few times, then let it eat.. 1 or 2 heat cycles should be fine.. WTH you think happens to engines when they get dyno'd?? They are fresh, get the **** ran out of them.. Don't be skeered

John

[arsenal35]

I have always done 3 heat cycles at first startup. I never let the head get anywarmer than I could stand to the touch. Then I wouldnt go any more than probably half throttle for about half hour of run time after that it was pinned a good bit of the time. I havent had a problem with it yet and it has been about 2 and a half years since rebuild.

[400exmxrider15]

Looks like im going balls out then! not scared no more, seem sketchy at first, but im alright with it now!

[250rforlife]

just ride it hard. but dont be revin the hell out of it like its a 2 stroke.

[400exrider707]

The idea is to put a good load on the motor for break in. Yes you can ride it hard and you should, but make sure you keep loading it, then unloading it.

My father used to race snowmobiles on a "somewhat professional" level back in the 70's and he said when they broke in new motors, they would go out to a frozen lake, start it up and hold it wide open for as long as they could for multiple runs. Apparently it worked, last championship I know of him winning was Vermont state championship for XC racing back in I think 79'ish.

With my quads, I have always broke them in following the moto-tune method. I buy cheap napa 10-30 oil, run it for 15 minutes and drain. I usually do this 3 or 4 times before switching to my good oils.

[Honda4life05]

just make sure to let it completly warm up COMPLETLY before you do it. I also did it the "motoman" way and it's still running strong.

[grassman]

Originally posted by 400exmxrider15
Looks like im going balls out then! not scared no more, seem sketchy at first, but im alright with it now!

Let me know how it works out for you. I will be rebuilding my engine too and I think Im gonna do it the "balls out" way too. Makes sense to me and I dont want to wait around to feel the power...:devil: