alx123 wrote:I always believe that the engine will warm up more quickly when running than when it's just idling.
That is true but you need to understand the point of warming up the engine and oil to get the big picture. To make things easier I'll just spill the beans.
Different metals expand from rising temperatures at different rates. Aluminum expands quicker then cast iron. Do you know what happens when you do not warm up a cast iron block/ or even a cast iron sleeved block with an aluminum piston?! You end up with nice juicy score marks from the piston expanding too fast in the bore to keep up. In addition the whole point of the oil warming up is so that oil can reach its peak lubricating ability to protect the engine.
Banging on your motor with cold oil is the last thing you want to do. It introduces accelerated wear and tear; in addition when oil is cold the oil is thicker making the oil pressure higher. Oil pressure rises as rpms rise. All the people with filthy oil tubes on their air boxes are guilty of this. That tube in the back is a good indicator of blowy/excess crankcase pressure which occurs from simply not allowing the engine to warm up..
However these motors are pretty tough so even a fool could get away with being reckless however if you have a Yuminashi 164cc kit with the cast iron sleeve you'll probably score the bore and piston skirts up being impatient/foolish.
I like your explanation of why we need to warm up our scoot. Aluminum does expand faster than steel. I think the amount of clearance between the piston and the skirt come into consideration when it comes to warm up time. Vehicles with smaller clearances, like racecars and high power sports cars, are more sensitive to warm up times.
I'm not too diligent on my warm up routine, most times I let it warm up as I put on my jacket and helmet. Then it takes me a few minutes to get to the Highway, which involves wide open throttle. Before my PCX, I was used to turn key and go. The only bike I used to warm up was a Yamaha V-Star 250, something about the choke and cold starts. I sold that thing, not as good as scooters. On a side note I will be adding a water temperature sensor to my scoot. It will be interesting to see how long it takes it to warm up.
One thing is for sure warming up the scoot does no harm and is most likely good for the longevity of the motor.
Gil
Re: 2016 pcx150 warm up question
Posted: Sat Oct 28, 2017 5:28 pm
by you you
If you think "warming up" is important due to the different coefficients of expansion and contraction do you also "cool down" in the same way?
Re: 2016 pcx150 warm up question
Posted: Sat Oct 28, 2017 9:38 pm
by springer1
Funny, I recall seeing a person on here with score marks along his piston skirt and blowby past the oil scrapers. In addition the clear tube at the end of his air box was disgusting and full of oil which I'm sure you know what that means...
OK, I know this quote was written a while ago but ....... Well, I'll admit that I'm not sure that I know what that means. I'll need to look in the Service Manual, is there a PCV valve that feeds from the crankcase to the airbox - and the thought is that the crankcase is getting pressurized from blow-by ?
I never had blow-by on my Norton, just 2 pistons rising and falling simultaneously (like all Brit Twins) which caused pressure havoc in its smallish pre-unit crankcase. The o/p from the crankcase vent (they didn't call it a PCV) was so normally oily that I re-routed it to just above the drive chain which kept the chain nicely lubed and insured the frame didn't rust. I figured it was a marvelous hi-tech innovation LoL.
I didn't know that failure to let an engine warm-up would gall a piston.
Re: 2016 pcx150 warm up question
Posted: Tue Oct 31, 2017 1:05 pm
by WI_Hedgehog
gn2 wrote:If its on the centre stand the rear wheel is in the air so no matter how hard you rev it the thing's going nowhere.
And you don't need to warm it up, it's ready to go as soon as it starts.
I meant side-stand, be near your ride so it doesn't take itself off the side-stand, of course it won't go anywhere on the center stand...thank you.
you you wrote:If you think "warming up" is important due to the different coefficients of expansion and contraction do you also "cool down" in the same way?
Kind of...if the cooling fan on a bike is running I wait until it evacuates the extra heat and shuts off, then I shut down the machine. On a turbocharged engine the last mile is done "really easy" so everything cools down. I've seen other people crack exhaust manifolds, weld valve seats, score cylinder walls with rings that got heat-soaked, etc. It could be I'm over-cautious.
Re: 2016 pcx150 warm up question
Posted: Tue Oct 31, 2017 3:32 pm
by PCX150Rider
To warm up or not to warm up. . .that is the question:
Whether t'is nobler in the mind to suffer
The slings and arrows of outrageous fortune
Or to take arms against a sea of troubles
And by opposing. . .end them.
T'is better to have warmed up and trashed an engine than to have trashed an engine and never warmed up at all.
Re: 2016 pcx150 warm up question
Posted: Tue Oct 31, 2017 5:10 pm
by WI_Hedgehog
To die, to sleep.
No more.
And by a sleep to say we end the heartache and the thousand natural shocks that throttle is heir to—’tis a consummation of fuel devoutly to be wished!
To die, to sleep.
To sleep, perchance to dream—ay, there’s the rub! For in that sleep of death what dreams of greater boost may come!
And from another passion:
Re: 2016 pcx150 warm up question
Posted: Wed Nov 01, 2017 5:26 am
by gn2
WI_Hedgehog wrote:
gn2 wrote:If its on the centre stand the rear wheel is in the air so no matter how hard you rev it the thing's going nowhere.
And you don't need to warm it up, it's ready to go as soon as it starts.
I meant side-stand, be near your ride so it doesn't take itself off the side-stand, of course it won't go anywhere on the center stand...thank you.
Have you tried starting a PCX with the side-stand down recently?
Go on, give it a go.
Re: 2016 pcx150 warm up question
Posted: Wed Nov 01, 2017 8:56 am
by springer1
PCX150Rider wrote:To warm up or not to warm up. . .that is the question:
Whether t'is nobler in the mind to suffer
The slings and arrows of outrageous fortune
Or to take arms against a sea of troubles
And by opposing. . .end them.
T'is better to have warmed up and trashed an engine than to have trashed an engine and never warmed up at all.
Yah, I agree with warming up a bit, but I'm not too sure about the video. But the video's mention of oil reminds me - I know my pickup's valves clatter unless I let it idle for 30 sec or so in the winter so there must be some sort of oil flow factor involved. Doesn't matter what weight oil I use.
"Back when", I was always told the reason to not rev until the choke was off was because the additional fuel in the rich mix "washed" oil off the rings & bore. I don't know whether it's related to oil flow or rich mix or both, but it's probably best to keep the revs down until the choke is off or FI idle revs drop.
Re: 2016 pcx150 warm up question
Posted: Wed Nov 01, 2017 1:20 pm
by WI_Hedgehog
gn2 wrote:
WI_Hedgehog wrote:
gn2 wrote:If its on the centre stand the rear wheel is in the air so no matter how hard you rev it the thing's going nowhere.
And you don't need to warm it up, it's ready to go as soon as it starts.
I meant side-stand, be near your ride so it doesn't take itself off the side-stand, of course it won't go anywhere on the center stand...thank you.
Have you tried starting a PCX with the side-stand down recently?
Go on, give it a go.
Crap, it won't! Well, I suppose that's reasonable. The 2016 motorcycle has to be in neutral, guess there's not really that on the scooter...older bikes had no such thing....
Re: 2016 pcx150 warm up question
Posted: Wed Nov 01, 2017 5:30 pm
by superandyp
Well if my sleeve gets scored badly I get to replace with a Yuminashi big bore kit, nice! I typically don't let mine warm up whilst parked, but I do ride at low revs for first mile or so. I do wonder whether it is more important for bikes with manual gear boxes to warm up first. As the bike accelerates away and the rider goes through the gearbox, the changes in rpm can be quite dramatic. With our scoots having a CVT the increase in revs is comparably smooth. May all of our PCXs keep going for years to come.
Re: 2016 pcx150 warm up question
Posted: Thu Nov 02, 2017 2:02 pm
by WI_Hedgehog
I'd think it more important for CVT bikes to warm up as they [potentially] hit higher RPM due to the clutch, whereas a manual can be short-shifted.
Re: 2016 pcx150 warm up question
Posted: Mon Dec 31, 2018 9:20 pm
by Inoplanetyanin
you you wrote:
Mike888 wrote:Hi I was wondering is 5 minute enough to warm up the scooter before a ride. Also I noticed when I start it from cold the rear wheel would move a little by after a 6 mile ride the rear wheel does not Move any more
You don't need to warm it up at all.
Warming the engine up before riding it prolongs the life of the engine. If one does not care but to have the bike for a short period of time, then sure, follow the advise above.
If you care for your scooter, a warm up of even a minute and a half is very healthy for the engine. All depends on the outside temperature of course.
By warming up, your piston and rings are allowed to gently reach their expanded size and prevents scouring on the cylinder walls. Bearings are also saved by gradual warm up before they are loaded.
To understand why a warm up is the safest and prudent procedure for the engine, think why athletes warm up before performing (e.g. think of a gymnast). Muscles tear when cold and don't work as well. Same goes with moving engine parts that are moving with force against each other while at different rates of expansion and with less than optimal lubrication.
Re: 2016 pcx150 warm up question
Posted: Mon Dec 31, 2018 9:42 pm
by raito
I say BS. Honda user manual doesn't say anything about warming the engine up before a ride. Athletes don't take 10W-40 oil. There are most probably more long-lasting Hondas in Vietnam than in the US. I went there last month. Honda is doing very well there. I don't think they take time to warm up any time of the day.
Re: 2016 pcx150 warm up question
Posted: Mon Dec 31, 2018 10:00 pm
by PCX2016
raito wrote:I say BS. Honda user manual doesn't say anything about warming the engine up before a ride. Athletes don't take 10W-40 oil. There are most probably more long-lasting Hondas in Vietnam than in the US. I went there last month. Honda is doing very well there. I don't think they take time to warm up any time of the day.
Actually it does, page 38 of the manual.
Re: 2016 pcx150 warm up question
Posted: Mon Dec 31, 2018 10:28 pm
by raito
PCX2016 wrote:
Actually it does, page 38 of the manual.
Let's see it. I have collected a few PCX manuals for different years and languages. These are the closest words I can find:
Screenshot_2019-01-01 32K97C000_eng - Honda_PCX150_2018 pdf.png (146.79 KiB) Viewed 1005 times
Re: 2016 pcx150 warm up question
Posted: Mon Dec 31, 2018 10:57 pm
by PCX2016
Well, it doesn't say it directly. If you follow the manual, you will warm up the bike, before you check the oil.
Re: 2016 pcx150 warm up question
Posted: Mon Dec 31, 2018 11:08 pm
by raito
That is for checking the level... You telling me you do this before every ride..?
Re: 2016 pcx150 warm up question
Posted: Mon Dec 31, 2018 11:15 pm
by PCX2016
raito wrote:That is for checking the level... You telling me you do this before every ride..?
I do this before the first ride of the day.
Re: 2016 pcx150 warm up question
Posted: Tue Jan 15, 2019 9:01 am
by WI_Hedgehog
The different metals expand at different rates, so warming them up slowly helps them warm at more the same rate. The viscosity of the oil is WAY, WAY TOO THICK when starting a cold engine, as the operating temperature is generally around 205F and the starting temperature is under half that, so the viscosity is about ten times too thick, minimum, if running full synthetic 0W-20 multi-grade oil. From a mechanical standpoint, it's best to warm the engine up for 30 seconds or so in warm weather simply to get the oil flowing (remember it gets pressed out of the bearing surfaces as those parts sit idle), then gently (gingerly) ride the scoot for five minutes or so until things are at least "warm." This will greatly extend the life of the parts and reduce maintenance.
If it's cold out then extend the warm up time, or perhaps if you have time put the bike on the center stand, start it, and let it warm up for a few minutes while you put your helmet and gloves on, adjust your backpack, whatever. Be practical with some forethought and life goes better in general.
