Warm up for oil change.

[Mtrain730]

Hey guys 2012 yz450 oil is shared between transmission and engine. I usually take my bike for a 10 minute ride before a oil change would there be any down side if I just let it idle for a couple minutes with out actually riding it and kicking it through the gears. There is times where it is inconvenient to take it out and ride it but if there is even a little benefit I will continue to do so. Thanks.

[torkd14]

I've always just let my YZ450's idle until the case covers feel nice and warm, never had any problems with this. I can't ride my bike where I live so it's the only way I can do it.

[grayracer513]

The only truly valid reason for warming the engine prior to an oil change is to oil the engine up thoroughly so it can better deal with the first few seconds after start up when the engine has no oil in the feed reservoir.  The downside to running before hand is that the oil that was slung around the engine during the warm up will have to find its way back down from everywhere in order to drain out.

[Mtrain730]

Thanks guys so from what you guys are saying it doesn't really Make a difference if you ride or just let it idle and its not even a must to let it run at all.

[mx369]

Always warm up your oil to get the dirt suspended in the oil. Otherwise it lays in the bottom of cases.  I swap the rear axle direction so that Yamahas bike triangle is on right side on 10s and up. Both drain plugs are on the right so having the bike lean that way drains more oil out. Also after warming bike I lean it to the LEFT(5-10seconds)  to drain the dirty oil sitting on top of the head. You will be surprised how much more oil your bike will need in refill. I also let the bike drain for about 24 hours. Why put clean oil in with dirty oil?

[Mtrain730]

I have in the past always warmed the bike up was just curious if there was a Benefit to actually riding the the bike over just letting it idle.

[grayracer513]

Always warm up your oil to get the dirt suspended in the oil. Otherwise it lays in the bottom of cases.  ... I also let the bike drain for about 24 hours. Why put clean oil in with dirty oil?

 

Dirt that was ever suspended in the oil, like when you last ran it, should be in the oil filter, don't you think?

 

As far as leaving dirty oil in the engine, it is unavoidable as a practical matter.  Notice that the amount required after a normal oil and filter change is 1L on say, an '08, and 1.2L total amount after a rebuild.  You won't get all of it unless you roll the bike over several times or something. 

[Piney Woods]

I really want to add something here but I better not.

[torkd14]

I really want to add something here but I better not.

You don't change your oil? Lol

[grayracer513]

I know people who don't.  My own father was for a time in the habit of buying a new Chevy each year and not doing anything whatsoever to the car until he traded it in the following year.

[mx369]

Dirt that was ever suspended in the oil, like when you last ran it, should be in the oil filter, don't you think?

ECAUSE th.  Notice turnedat the amount required after a normal oil and filtee poil is dityr change is 1L on say, an '08, and 1.2L total amount after a rebuild.  You wo!n't get all heof it unless you roll the bike over several times or something. 

So, you are saying the filter catches the dirt in the oil. So why do we change the oil and just not the filter?  BECAUSE the oil is contaminated with all kinds of crap! Unburned fuel, bearing wear, clutch debris, no name a few. That's why you change it warmed up. Stuff does settle to the bottom of your cases! Your filter only gets the big stuff

[grayracer513]

The primary defect in used oil changed at a sensible intervals in a YZ450 or similar is loss of viscosity due to the destruction of long chain polymers by the transmission, not contamination.

 

You can see all the stuff that's built up in the cases on mine.  Cases in as-opened condition, nothing cleaned up or wiped away, after more than 300 hours of changing the oil "the wrong way".

 

 

[offshores]

The manual says, "Start the engine and let it warm up for several minutes." Says nothing about riding it. That's the way I've always done and that's the way I'll continue to do it.

[Kennethyz450f]

Wouldnt you want to get the oil heated up and moving around as much as possible before an oil change. What I was taught 

[grayracer513]

When you start the engine to warm it up for "several" minutes, you dump raw gas into the crankcase because of the rich mixtures needed for a cold start.  Gas gets pushed past the cold rings into the oil.  Normally, 99% or more of that gas will evaporate away if the engine is brought to normal operating temperatures and ridden for 15 minutes or so.  A quick warmup that doesn't heat the oil to at least 160 ℉ just adds contamination, not all of which will drain away.  Your spark plug doesn't really like being shut down cold, either.

 

The ideal practice would be to drain the oil after a ride, once the oil has cooled to below 160 ℉ so it isn't a burn hazard. That avoids the fuel contamination and improves drainage from up the engine. 

 

IMO, however, the important thing is to change the oil frequently, with a clean filter each time.  The rest is splitting hairs.

[Mtrain730]

When you start the engine to warm it up for "several" minutes, you dump raw gas into the crankcase because of the rich mixtures needed for a cold start. Gas gets pushed past the cold rings into the oil. Normally, 99% or more of that gas will evaporate away if the engine is brought to normal operating temperatures and ridden for 15 minutes or so. A quick warmup that doesn't heat the oil to at least 160 ℉ just adds contamination, not all of which will drain away. Your spark plug doesn't really like being shut down cold, either.

The ideal practice would be to drain the oil after a ride, once the oil has cooled to below 160 ℉ so it isn't a burn hazard. That avoids the fuel contamination and improves drainage from up the engine.

IMO, however, the important thing is to change the oil frequently, with a clean filter each time. The rest is splitting hairs.

That is actually one of the main reasons I asked grey is I know that it's not the best idea to start and stop the engine because it will contaminate the oil with gas that's why I thought going on a ride where the motor could run for a period of time and fully warm up would be a better idea. I thought if I pointed out that was my reason for asking the question people would think I'm crazy to worry about some thing like that. Like you stated obviously either method will work and is better than not changing your oil.