Too Long to Warm Up

[Urbestfriend]

 Anyone have a comment on why (in this colder weather) it take about 5 minutes warm-up
to get any power.  It starts right up.  Couldn't seem to find anything in the manual.

[Agil]

...move to Hawai...or to Croatia.. ..here is a photo from my yesterday riding ( beutiful sunny day -8 deegres Celsius )

[yvg]

Anyone have a comment on why (in this colder weather) it take about 5 minutes warm-up
to get any power. 

It is OK, I have the same on all GY6 50cc engines here for temperatures below +4..+5 Celsius, tested down to -20 Celsius.

You anyway have to warm it up for minimum 5 minutes before you ride at neg. temperatures.

Yury

[phin63]

I've gone for a couple of rides recently (December/January) here in the north east region of the U.S., and even if I let it idle for for five or more minutes it still doesn't really warm up until I ride it for ten minutes or so. We're talking about a small air cooled engine so I just think that it is the "nature of the beast". If you ride in cold weather then you must give extra attention to road conditions. Even a small amount of ice or snow can be dangerous.  Paul

[Urbestfriend]

Apparently Kymco is prone to this "Cold Weather Warm-Up" issue.  I expected someone to
comment about a carburator / choke issue.  I also have a Vino 125 that starts right off everytime.
I too am in Midwest USA.   Any day it gets above freezing  (32F/0 C),  I'm out riding,  even if it's a
few miles.   I usually commute to work (12 Miles) leaving home at 5:00 a.m.,  but it's mid winter
right now,  so I drive the truck or car.   All my rides have extra LED lites,  plenty of reflective tape
and I wear an ANSI Fluorescent coat (like London Police).   Haven't had an issue yet.

By the way,  I enjoy the international comments.  This forum is slow,  but can be interesting.
I also have an 84  Yamaha Razz.

[CROSSBOLT]

I have noticed the Agility 50 is a bit "cold-blooded." I think this relates to the electric auto choke which is a programmed event unrelated to engine temp.

Karl

[jprestonian]

If it's any help... my Yamaha Vino Classic 50 2-stroke is much the same way. I have no problem starting it in cold weather, but letting it idle for even 10-15 minutes has no real effect. Only after being ridden for 10 minutes or more does the throttle response behave normally. Prior to that in cold weather, it bogs, nearly dying... acts almost as if it's getting slightly flooded. My scooter guys seemed to think it may need a jet change for cold weather.
.

[Whitewolf]

I got the same "problem" when starting at close to freezing temp.Riding it "cures" it faster. What bothers me is that when temp drops in the same "area" the starter turns but doesn't engage the engine.It takes 4 or 5 tries before doing its job. Any body has knowledge about this? Thank you!

[CROSSBOLT]

Yeah, Whitewolf! I know the answer to this one: take your starter bendix out, clean it up if it needs it and lube it LIGHTLY with low temp grease or oil. Probably a graphite product would be the best choice. Let us know what you wind up using and how it works.

Karl

[Whitewolf]

CROSSBOLT,I appreciate your help. My 1000 km service is coming shortly. As soon as they are done I'm gone let everybody(on this site) know what they did. Regards.

[OldGuy]

I've been giving this topic much thought since it first appeared, and now believe that the problem ya'll are having  isn't with "warming up" per se, but with the amount of time it takes for the fuel enrichment circuit (The choke although it's technically not a choke. If you have experience with old carburetors you remember that the choke was a simple plate that reduced the amount of air the carb would flow thus enriching the mixture.) to shut off.

The actual warm up time is, simply put the time it takes for the engine's metal parts to get warm enough to insure that the fuel vaporizes. (Liquid fuel will not burn, fuel in vapor form does.) When starting cold, the fuel enrichment circuit (For simplicity, lets just refer to it as the choke.) adds more fuel than is normally needed to make the engine run. More fuel increases the likelihood that enough fuel will vaporize to get the engine to run. That's why most vehicles produce more emissions on start-up.

If the engine is warm and the choke doesn't shut off the engine runs rich and produces the symptoms you describe.

Since I would suspect the the controlling device is nothing more than a heating element and a bimetallic strip

(see here:
http://home.howstuffworks.com/home-thermostat1.htm )

for a solution I would start at the electrical side and check all the connections to the "choke" and make sure that they are in good, clean condition and making good contact. Any added resistance in this area will keep the heating element from warming the bimetallic strip at the expected rate and slow down the shut off of the choke.

[phin63]

 I like the more specific answer answer from "Old Guy". I was thinking in a more general way. The motor being small (generating a relatively small amount of heat) and air cooled (with cold winter air) was just being overwhelmed initaily. I think that we all appreciate the input.   Paul

[yvg]

Well, in my case it is not necessary to drive to get accelerator reacting. If I warm up for 10 minutes at -5 Celsius, it definitely goes well. Few days ago I had a fun ride on a pure ice with summer tires, it took approx. 15 minutes to make 1,5 km with a lot of fun, but I have to admit that engine was performing and reacting quite well.

I believe that for colder weather you shall re-adjust the carb, which is anyway rather simple procedure and especially on Agility 50 does to require any disassembly - you just need long enough screw driver (OK, I use 40 cm flat one), and another one (cross) to adjust the idle RPM. I still believe that you can live with the same jet both summer and winter.

Yury

[Auld.Nick]

I have exactly the same problem.  Takes the bike 10-15 minutes to warm up.  If I try to ride it before it is fully warmed up it will not respond when power a re-applied.  Usually happens as I'm pulling into a junction, scary!  Took it to the dealer in Northern Virginia and they charged me $150 and told me to let it warm up fully.  Got a cock and bull story about there being a wax part that needed to melt before driving the scooter.  I left in disgust.  I suspect that they never tried the scooter outside their climate controlled work shop. 

I've got some online advice .  I've been told to check the auto bystarter (which as best I can tell functions as a choke).  Down load the service manual (it's available online as a pdf) and look at section 5


The advice I got was to check the plunger for corrosion. 

Remove the  auto bystarter and apply 12 volts to the terminals and see how long it takes for the plunger to move out.  The auto bystarter should get warm very fast.     I'm going to try doing this this weekend and report back to my 'advisor'.  I'm not sure how long it should take for the plunger to move etc.  I'll post back what happens.  The service manual appears to have a similar test (see below)

Hope this might help someone as I know you pain and frustration.  If anyone out knows if this make sense or knows of a solution I'd love to hear about it.  Seems like this might be a common problem with the Agility.





The service manual has the following

AUTO BYSTARTER
OPERATION INSPECTION
Measure the resistance between the auto
bystarter wire terminals.
Resistance: 10? max. (10 minutes
minimum after stopping the engine)
If the reading is not within the limit, replace
the auto bystarter with a new one.


Connect a hose to the fuel enriching circuit of
the carburetor. Connect the auto bystarter
yellow wire to the positive (+) terminal of a
battery and green wire to the negative (-)
terminal. Wait 5 minutes and blow the hose
with mouth or vacuum pump. If the passage
is blocked, the auto bystarter is normal.
Disconnect the auto bystarter from the
battery. Wait 30 minutes and blow the hose
with mouth or vacuum pump. If air can be
blown into the hose, the auto bystarter is
normal.

REMOVAL
Remove the set plate screws and set plate.
Remove the auto bystarter from the
carburetor.

AUTO BYSTARTER INSPECTION
Check the auto bystarter valve and needle
for nicks, wear or damage.
If any faulty part is found, replace the auto
bystarter as a set.

INSTALLATION
Insert the auto bystarter into the carburetor
body until it bottoms.
Position the set plate into the groove in the
auto bystarter and tighten the screws.

[OldGuy]

While we're on the subject of warm-up thought it worthwhile to mention one other thing. All gasoline engines, no matter what the size do not warm up well by being left idling and doing so is not good for them.

At idle, any gasoline engine uses a very rich fuel/air mixture primarily for two reasons. The energy needed to overcome frictional losses and low port velocities. This is true even when the engine is warm and the problem is exasperated when the fuel enrichment circuit is activated. The excessive fuel actually has a cooling effect due to evaporation and the excess fuel washes the lubricant off the cylinder walls.

The problem is even worse with a 2-stroke engine since the oil injector pump puts out less oil at low RPM's. Seems like I read somewhere that at idle the oil/fuel mixture falls as low as 100:1.

My advice; Let the engine idle for about 30 seconds at most and drive off at a moderate pace. The engine will warm up quicker and be happier.