How To Break In an Engine?

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Active Member
Apr 26, 2015
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Hi guys, just got shipped a brand new Lifan 125 engine for my pitty, first question- Should I drain the oil straight away and put proper brand stuff, what happens if I dont?
2nd Question- Is The engine already factory tuned eg- Timing valves etc
3rd Question- Whats the best way to break in the engine? Cheers
Jun 13, 2013
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stowport tas
You can run them in on the crap they ship them with, but you would have to change it as soon as your run in period is up. I change my oil as soon as i get a new engine though as it is pretty much chip oil they ship them with lol.
Valve clearances shuld always be checked on a new engine, the chinese can get pretty lazy with that sort of thing.
Best way to run it in is in 20 minute intervals, with varied throttle input (not full throttle though) over 3 to 4 tanks of fuel. So give it twenty mins of running, let it cool down, repeat.

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Miniriders OG
Feb 9, 2009
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sydney... north of
like every other post in internet history regards breaking in an engine, there will always be the other method...

me myself and i, prefer the hard break in.

check it all over first, so yeah, valve clearances, decent MINERAL oil...

start her up and resist all urges to open the throttle. let it idle and go get a cup of coffee or a smoke or something.

nice and warm, take off in 2nd gear, holding the brakes on. full throttle. not about revving the engine, but about getting the maximum PRESSURE on the rings so they bed in to the honed cylinder bore. rings work by combustion pressure forcing them DOWN onto the piston, and OUT into the cylinder wall. a good five minute, full LOAD (not necessarily speed) first run.

then drop the oil and marvel at all the metal filings that are in it. and wonder why the hell manuals tell you to leave that dirty muck in there for the first "1000km".

fresh oil, repeat. repeat again. aim to change the oil every half hour for the first few times. whats a 4 litre bottle of mineral cost ya? $35? sweet eff all. once it STOPS coming out all glittery, leave it. go for synthetic if you really think it does anything other than cost a heap. and marvel at how long it tends to stay clean forever after. no piston blow by contaminating it. no loss of combustion pressure past the rings... an engine that seems to outpull all your friends that did take it easy at first...

then you can start jetting it, drop in those lumpy cams, etc...

they dont do it with chinese engines, but every reputable manufacturer actually does exactly this to every vehicle that comes off the production line. let them warm up gently, then full throttle the damn things, wind through the gears, make sure nothing explodes due to an overlooked flaw... far easier to grenade something in the factory, and reclaim whats left than to have a customer do it the day they buy it and replace the whole thing under warranty.

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