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Orpheus
01-04-2009, 04:26 AM
Okay, here's my problem:

A couple of weeks ago, it got pretty cold here in the desert, like around freezing. My GZ wouldn't start at all; I eventually wore down the battery trying to start it. I had the choke all the way open and had plenty of gas. I haven't had any problems before or since. I ended up having to push-start it and it started right up. Could it just be that my bike hates the cold or should I be ready to start looking for a new battery? I've always had problems starting it in the cold (even last year when I bought a new battery), and I'm thinkin' that it's just a temperature thing. Any suggestions?
Thanks.

mr. softie
01-04-2009, 04:55 AM
When it is cold out I usually pull the cold start lever "choke" full on, then crank for 4 or 5 seconds. If the motor doesn't start I wait a bit and try again. I don't give it any throttle. If it still won't start I wait a bit more and try with the lever about 3/4 on a few times. By cold I mean 35 degrees and colder. Above 35 degrees or so I don't use full choke, but when it is really cold My bike will not start without the lever all the way on. I try not to crank for more than 5 seconds at a time. After it starts I let it run a bit before I give it any throttle. Hope this helps.

alanmcorcoran
01-04-2009, 05:24 AM
Orph,

I have trouble starting mine when it's in the low 40's. I pretty much do what Mr. Softie does to get it started. Mine still tends to stall at the first few stops. Fortunately, I have become expert at the "starter-less" restart (basically, let the clutch out in second on a downhill, which I have ample on the way to work.) (I do not stop in Neutral, but in First with the clutch in [Second if I'm pointing down]. I sense this is not recommended, but it's a habit that goes al the way back to driving a stick.)

I'm not mechanically inclined, and know very little about the bits and pieces of the GZ start/ignition system, but it seems to me like there IS a thermostat on it that affects the idle. (I think it's air-cooled so, I don't know exactly where the thermostat would live, but I'm just theorizing.) And mine is crap (assuming there is one.) With the choke full on it will sometimes race the engine, and, seconds later, drop to a near stall. After about 10 to 15 minutes, it settles in nicely. But for the first 10 minutes, stalling is not unusual. And remember, I live in sunny So cal.

Easy Rider
01-04-2009, 10:57 AM
I had the choke all the way open and had plenty of gas.


Some thoughts:

When cold and the choke is operated, that would be closed, not open.

Usually best to close choke fully, run starter only a couple of revs (2 seconds) and then crack the choke open a bit, maybe closed only 3/4, and try again a little longer. At the first sign of a fire, blip the throttle just a tiny bit.

Once started don't open the choke all the way until it warms up. You should be able to find a point on the choke where the engine will idle a bit fast without racing. While the little beast is somewhat erratic while cold, mine never dies if I leave the choke on just a bit for the first 2-5 minutes.

This could also be a sign that the idle speed (when hot) is set too low.
It could also be a sign that it's time for some carb cleaner in the gas......or that the air filter is getting dirty.

And no, Alan, there is no thermostat; it's just the crappy lean lo-speed carb mixture setting that causes it.

mrlmd1
01-04-2009, 11:12 AM
If it's that cold for an extended period of time and you don't run the bike every day for a half hour or so, it might pay to keep the battery hooked up to a small charger to keep it topped up, That might be part of your problem. And a dead battery can freeze, and then it'll never be the same, may never work again.

I don't use my bike every day but even when cold it starts within a few seconds with 3/4-full choke, then as it races, slowly turn down the choke, wait 30 seconds, turn it down more, start riding. It never stalls. I have the choke off within a minute or so and maybe one block of riding. It warms up pretty fast, just be gentle with it for the first 1/2 mile or so and you won't have any problems.

Easy Rider
01-04-2009, 12:43 PM
If it's that cold for an extended period of time and you don't run the bike every day for a half hour or so, it might pay to keep the battery hooked up to a small charger to keep it topped up,

So true. Harbor Freight has one for about $15; better ones for $25-30.
AND......once you run it down, you really need to give it a full charge with an exteranl charger to be sure it is back up to snuff. Sometimes "normal" riding won't do it.

Also, if it's not been run for a few days, it might help to move the petcock to PRIme for a few minutes before you try to start it.

alanmcorcoran
01-04-2009, 04:46 PM
Don't want to start another endless circular argument, but, for the record, not all GZ's behave the same in this regard. Although I am not a mechanic, I am familiar with the concept of the choke (or lean-ness adjuster) and how to operate it and I can tell you that mine takes a lot longer to settle in than 1/2 mile (more like seven-ten miles) and I am probably starting with a warmer temperature. It may very well be that my idle is set too low, or at least lower than mrm's, although, after ten miles, with the choke completely open, it is nice and quiet at the traffic lights and doesn't stall anymore. It may be, given I am in a warmer climate, the dealer sets the idle a little lower.

It might also stall less in true neutral rather than with the clutch in (in gear). Plus I have a little too much oil in mine which tends to reduce the clutch "travel" and make it a bit "grabby" at the get go (I am making these terms up as I go along...)

I have also investigated the possibility that the choke cable is "sticky" (mainly by sliding it around some) to see if that explains the wide RPM drifts at idle w/the clutch in, but it seems like it is just a bit flakey until it is fully warmed up. I have not tried carb cleaner as the bike purrs once it warms up - and therefore this is probably not an issue. Plus I only have 2800 miles on the thing.

Anyway, that's my experience. As far as starting goes, I agree with all of the advice given. (FYI, I ran my battery down to nothing with a dumbass taillight mistake very early on, but I push started it and it's been working okay ever since. Battery seems to recharge pretty quickly despite what I was told by a dealer.)

music man
01-04-2009, 05:29 PM
This probably doesn't have anything to do with it, but I wonder if there is a big difference between a California model GZ and say My GZ, as far as how it is setup up with the fuel/air ratio.


Cause we all know that you California guys have to be sooooo different from the rest of us. :neener:

Easy Rider
01-04-2009, 05:49 PM
It may be, given I am in a warmer climate, the dealer sets the idle a little lower.

Plus I have a little too much oil in mine which tends to reduce the clutch "travel" and make it a bit "grabby" at the get go (I am making these terms up as I go along...)



I think MM is probably on to something, BUT......

Alan, buddy, you are jumping to some erroneous conclusions.

The idle speed adjustment is a white knob right below the right side of the carb. You should learn how to operate it!

Whatever your clutch is doing is likely NOT related to the couple of extra ounces of oil you have in there. Sounds to me like you need to check the slack in your lever/cable; too much slack = clutch drag.

OTOH, based on previous attempts at mechanical analysis, these might just be dilusions !! :poked: :biggrin:

It takes mine a lot longer to become stable after a cold start too.......but it doesn't die; just sounds like it's idling too slow if I turn the choke off too soon.

Moedad
01-04-2009, 05:56 PM
My California GZ starts with me opening the choke to more or less the halfway point every morning. It cranks for maybe 2-3 seconds at the most. I listen to how it's idling for a sec and adjust as needed then put on my jacket, helmet, and gloves. In the summer I close the choke when I get on the bike. This time of year I leave it open until the 1st traffic light which is less than a half mile from my house. So far in seven months, it's stalled once using that routine. It does not idle fast at stops.

alanmcorcoran
01-04-2009, 09:52 PM
Mine might not be set up properly. You guys might recall that my left blinker didn't work, the mirrors fell off and the tires were not properly inflated, despite the unconscionable "dealer prep" charge. I will investigate the idle setting, but I am inclined to leave it alone as the engine has never stalled after ten minutes of riding. I just think mine just takes a little longer to stabilize. I'd rather be a little careful in the ten minute zone than have the idle up too high. I stalled today at my second stop sign, about 30 seconds from the house. Did not have the choke all the way on though (about 3/4). (It was about 65 today!) Wouldn't catch with the starter so I just rolled it and let the clutch out. I've gotten pretty good at that - can pretty much do it as easily as pushing the starter button at this point.

Easy Rider
01-04-2009, 10:02 PM
Mine might not be set up properly.
Did not have the choke all the way on though (about 3/4). (It was about 65 today!) Wouldn't catch with the starter so I just rolled it and let the clutch out.

Holy crap! :shocked:
If I leave the choke at 3/4 for more than 10 seconds or so, mine sounds like a Piper Cub about to take off. Add that to the not starting and I think you definitely have something wrong.
Has it always behaved like that?
I think you need some warranty work and/or a carb cleaning (yes, at only 2800 miles).

alanmcorcoran
01-04-2009, 10:34 PM
It's basically flaky. If I leave it up at 3/4 sometimes it races, but if I move it down, it will die. In fact, If I just leave it alone, it will race, then not race. It seems to have a real problem with going from very high engine/ transmission revs, back down to very low. That's when it will stall. If I'm sitting at a light, sometimes it will drop from racing down to slow idle, and vice versa. That's why I thought there was a thermostat.

But, like I said, after about ten minutes, it all settles down and I turn the choke completely off (wide open) and it idles very low, quietly, and doesn't quit.

I have noticed a rather sharp drop in mileage of late as well. Used to get 170ish before I switched to reserve. Now, I've run out in the 140's. I am riding it more aggressively, higher rpms all around and harder acceleration.

If there was a problem with the carburator, wouldn't run like crap after it warmed up too?

alantf
01-05-2009, 09:59 AM
At the moment it's about 10ºC/ 50ºF. I don't have any problems starting without the choke (European/Spanish GZ), & it warms up completely after about 10 miles, & then the engine note changes to a throaty rumble, & all's fine.
The problem I've always had (I've got 9000km on the clock now) is that whatever the temperature, & whatever the engine temperature, if I close the throttle completely the bike gives a sudden jerk as the revs die, so I have to get the clutch in at a much higher speed than the handbook says, just to avoid the kick in the back. I've never had this with any other bike. Is this common to the GZ, or just to my bike? incidentally, the tickover is set high enough so that once I'm out of the garage & onto the open road, it never stalls at stop signs.

Easy Rider
01-05-2009, 10:36 AM
If there was a problem with the carbureator, wouldn't run like crap after ti warmed up too?

Maybe not. The little beasts are so lean to start with that any tiny little thing can throw it over the edge to "too lean to run right". Being lean is not so important when the engine is warm.

Most newb's tend to gauge the idle speed by what they are used to hearing and feeling in a car. Not the same. Most modern cars idle about 800 rpm; most bikes a minimum of 1000-1100. A proper idle on a GZ "feels" a little on the fast side.

I still think it would be worth your while to spend $4 on some Gumout, Berryman's or Seafoam and put a healthy dose in a couple of tankfulls.

Easy Rider
01-05-2009, 10:41 AM
The problem I've always had (I've got 9000km on the clock now) is that whatever the temperature, & whatever the engine temperature, if I close the throttle completely the bike gives a sudden jerk as the revs die,

It's normal but seems to be more pronounced on the GZ than other bikes I've owned.
You can minimize it by keeping the idle speed UP and being sure you don't have too much slack in the chain. Others have reported that there is too much slack in the rubber drive cushion inside the rear wheel and changing that helps.

About the only way to eliminate it completely is to be careful not to close the throttle abruptly.

Water Warrior 2
01-05-2009, 08:05 PM
I think Easy has the answer. Too lean to run right. Lynda's bike can't make up it's mind on how to run when started up on a colder day. Won't run with full choke without screaming at high revs and backing off the choke a bit will kill it almost instantly. Seems to be a combo of choke and throttle to keep it running until some heat developes and it is happy after that. Fuel Injection is the ultimate answer.

alanmcorcoran
01-06-2009, 02:22 AM
Lynda's bike can't make up it's mind on how to run when started up on a colder day. Won't run with full choke without screaming at high revs and backing off the choke a bit will kill it almost instantly. Seems to be a combo of choke and throttle to keep it running until some heat developes and it is happy after that.
:plus1:

That describes my GZ perfectly.

Water Warrior 2
01-06-2009, 05:18 PM
Lynda's bike can't make up it's mind on how to run when started up on a colder day. Won't run with full choke without screaming at high revs and backing off the choke a bit will kill it almost instantly. Seems to be a combo of choke and throttle to keep it running until some heat developes and it is happy after that.
:plus1:

That describes my GZ perfectly. Smaller engines with smaller carbs would also be more sensitive to a choke setting. Larger engines will be more forgiving of fuel mixtures in most cases. Now all you need is a FI V-twin from Japan. I would suggest a VStrom but I don't think you would like it (well you might), it has a FI 650 cc / 90 degree V-twin that is so smooth that nothing ever vibrates.

alanmcorcoran
01-06-2009, 09:57 PM
I think the Stratoliner had a FI V-twin (but I might be mistaken.) It certainly didn't vibrate, and was super smooth. I had a grin on a mile wide the whole time I was on it and I'm not much of a grinner.