We just had our 2005 Honda Rubicon engine rebuilt at about 10,500 miles. The engine did not need to be rebuilt but we had it in the shop to install a new timing chain and it wouldn't cost that much more to rebuild the engine. The engine still had plenty of compression.

Anyways, we just got it back and wondered is there a proper way to break in an engine? I have always known to take it easy on a new engine but there are some people that says drive it like you stole it and others say take it easy.

I know you are supposed to change oil after 100 miles or so but is there anything else that should be done?

 

In all fairness you will get as many answers to your question as there are stars in the sky.

Here is what I know:

Rings need to load against the cylinder to break in the best. The only way to load a ring really hard is to give it lots and lots of air. The only way to do that is to give it lots of throttle.

The only way to break a cam in is medium to high RPM. You never break in a cam at idle. It too hard on them to do that.

All racing engines are loaded on the dyno. They warm them up and make the pull at WOT.

You ever hear of anybody breaking in a chainsaw engine softly? Or do they do it like me and start it up, warm it up and go full throttle until it runs out of fuel? Same way with leaf blowers or lawn mowers or lots of other engines.

Do what you want, but this is why I break my engines in the way I do. I'm sure others will disagree.

 

I just got a new quad and the owners manual stated for the first 100 miles or 10 hours avoid constant low speeds, do not run full speed and try to modulate the throttle between mid speed and full throttle. Basically down go slow and don't ***** out full speed for extended periods and change oil and filter after the 100 mile or 10 hour mark.

 

Ride it easy for about a an 2 hours...let it sit over night... and do this over again....then change oil.... Thats how I was taught to do ..... Last year I didnt break the motor in on my back up quad properly and I pulled it out of the trailer at the track because on my other quad I snapped frame in half...An the took the back up quad out an burnt the oil until the motor was bone dry because it was a long race and I was never broke in

 

Thanks for the replies.

Is there anything that should not be done while breaking in an engine? Is shutting it on and off constantly hard on it? See, we live on a dairy farm and we are constantly using it. Sometimes we will only drive it a couple tenths of a mile and shut it off. Is driving it before it is fully warmed up hard on it?

 

You should start the new engine with fossil oil only in it(synthetic is too slick,and will ruin a break in) up using as little choke/enrichener as possible allow it a few seconds to fully circulate the oil then go out and run the machine wot through the entire gear range,running it up,and then slowing it down using engine braking,not the brakes,keep doing this for 15 minutes to half an hour,shut it off,allow to go cold to the touch,check oil level,do it again,and repeat this process several times over the next 2 days...Warm it up,look for oil leaks,or smoke-if none,allow it to run for 10 minutes,shut down,drain oil from both drain plugs,change filters,refill with your favorite brand of oil as long as it is a wet clutch spec'd oil (I use Rotella T6 full synthetic in my 04 Rubi,18 bux from wally world),and it will last you another 20k provided the Hondamatic holds together that long...Good luck!! p.s. If you try to break in any engine gently,the honed scoring edges in the cylinder will smooth out,and they will not cut the rings in,nor will the rings expand as they need to in order to get filed to the cylinders bore shape(it isn't always perfectly round even after a fresh boring)which results in engine smoking,high oil consumption,low power,etc...