Are these things always so cold blooded?

[efjay_62]

Quite frankly, my bike is a cold blooded turd. I can go out roughly 10 minutes before getting ready to leave in the morn, or for that matter, even after work or any time that it has been sitting long enough to "cool down", and let it run on the choke, and when I take off, I still have to feather the throttle and use a lot of clutch to take off, for the first few blocks, maybe up to a mile or so, before it gets good and hot and will run well. Once it gets warmed up, it runs quite nicely. I bought it in poor running condition, so I have nothing to base it's current cold running ability against, other than friends bikes. It has a freshly rebuilt head, rebuilt carbs, replaced the boots boots, new a lot of stuff. I had the carbs synced last year after putting them on and getting it running again, and they all synced fine. It would pop alot when cold, even running on the choke last year with the old, blown out stock mufflers. I just put HD muffs on it, which actually improved the cold popping. I'm sure it is a bit lean, because I do get some minor decel popping in the 2-3k RPM range, but that also improved with the Harley pipes compared the old stockers.

Is this poor cold running performance normal for these old machines, or is there some further tuning needed somewhere? I have a Dyna-S kit waiting to go in, but I can't imagine that helping it any. It can be quite annoying, especially when riding with buddies, that I have to go start up way ahead of time, and it still runs crappy at first, and they can just basically start and go.

TIA.

 

[srsupertrap]

It sounds like did not adjust or fine tune the pilot fuel screw & pilot air screw. Do a search this topic is well addressed

 

[Steve]

If your carbs are clean (I know you said they were "rebuilt" recently, but that does not mean "clean") and your pilot mixture is correct, you should be able to start the bike and ride off within 30 seconds or so, definitely within a minute.

Your bike was built in the era where they were starting to worry about EPA regulations, but still did not have it right. Your pilot fuel screws (the ones on the bottom of the carbs) should be about 5/8 to 3/4 turn out from lightly seated. Your pilot air screws should be about double that, or 1 1/4 to 1 1/2 turns out from lightly seated, then turn them slowly, listening for highest engine rpm (when the engine is fully warmed up).

My guess is that your fuel screw is probably no more than 1/2 turn out or your air screws are too far out.

.

 

[bwringer]

If the "rebuilt" carbs included the shoddy imitation crap found in rebuild kits, you may need to install OEM jets, needles, etc. to get it running right.

With that said, no, there's no reason at all your GS should be cold-blooded. With stock intake, carbs, and exhaust in good shape and the idle mixture properly adjusted, it should fire instantly and warm up in seconds in any weather.

Of course, any modifications to the intake or exhaust require rejetting, and any deficiencies, air leaks, etc. MUST be corrected. Sounds like you're running quite lean with the modified exhaust, and need to rejet before you do serious engine damage. What color are your spark plugs?

 

[efjay_62]

If the "rebuilt" carbs included the shoddy imitation crap found in rebuild kits, you may need to install OEM jets, needles, etc. to get it running right.

With that said, no, there's no reason at all your GS should be cold-blooded. With stock intake, carbs, and exhaust in good shape and the idle mixture properly adjusted, it should fire instantly and warm up in seconds in any weather.

Of course, any modifications to the intake or exhaust require rejetting, and any deficiencies, air leaks, etc. MUST be corrected. Sounds like you're running quite lean with the modified exhaust, and need to rejet before you do serious engine damage. What color are your spark plugs?

I JUST got the "new" exhaust put on, and have only had it out a few times since. I have not pulled the plugs. But, as I mentioned, the run condition actually improved, as in got better but not completely cured, over the old stock mufflers. I figure the old original mufflers were pretty rotted out inside and at least a good percentage of the baffling was blown out, because they were quite a bit louder than I expected. And this cold run condition existed last year with the old exhaust. It sounds like I need to do a little tweaking on the carbs and go from there.

 

[efjay_62]

So I was gonna play with my carbs tonight, and looking at them, I only have one mixture screw, right behind the air box inlet, going downward at about a 45 towards the bowl. Does this sound accurate?

 

[tkent02]

No, that one is the pilot air screw. The pilot fuel screw is underneath the carb, in front, you reach it through a little recess in the float bowl. Be very careful not to bottom it, there is a tiny metering tip made of soft metal, if it jams in it's tiny port the tip breaks off. Then the carb won't work right as the pilot (idle) circuit is blocked, no fuel flows until the throttle is opened. You need to disassemble them all to get the broken tip out, it may require replacement of that carburetor body. Just screw them all out from where they are 1/4 turn, see if it helps, maybe go another 1/4 if need be. The screws may be stuck in place, if so don't mess up the screw head.

Cold blooded running like you describe is often caused by these tips being stuck in the port, it is very common.
Or those tiny passages are clogged by gunk or debris.

You say the carbs were rebuilt, but not who rebuilt them, few understand how they work anymore, it is not likely they were done very well.

Most likely the carbs will need to come off for a thorough cleaning, they mostly all do.

 

[efjay_62]

Tkent, I actually did the carbs myself. I know that may come with mixed reviews, but I am a boat mechanic for a living, and have rebuilt literally countless carbs, both automotive type and small engine, on outboards. The thing foreign to me is being air cooled, and having seperate air and fuel mix screws. All the carbs that I work on have one or the other, not both. I know when I had the carbs synced after putting them back on the bike, that the guy tweaked the mixture screws some. I adjusted them this evening, and it seems way better. The popping is probably 90% gone, I believe the rest may be attributed to a small exhaust leak I noticed. And as for the cold running, I will know for sure later in the weekend, the next time I get a chance to ride, after it has been sitting for a few days, but I adjusted them while the motor was cold (after sitting for 9+ hours during the work day), started it up, and was able to take it off choke and did a handful of "test launches" within maybe a minute of startup, and it performed quite nicely. I then let it warm up a few more minutes, and try tweaking on the air screws to see if anymore improvement could be had, and it really seemed pretty happy where it was, so I just left it. I didn't really even try messing with the fuel screws anymore, cuz the inner ones (especially #3) aren't the easiest to get too. I just set them at 3/4 of a turn and went with it.

Like I said, I'll see how it is the next time I cold start it, but I think it's pretty good.

 

[CR_GS_450]

Any news? I have this same issue, but mine is only a few minutes, not ten. I also have the CR's with Pods and exhaust so it may just need a proper adjustment. Thanks.

 

[Steve]

Any news?

Just look at the post immediately before yours. It was posted 5 1/2 days before your post, so you should have seen it. :-k

... I adjusted them this evening, and it seems way better. The popping is probably 90% gone, I believe the rest may be attributed to a small exhaust leak I noticed. And as for the cold running, I will know for sure later in the weekend, the next time I get a chance to ride, after it has been sitting for a few days, but I adjusted them while the motor was cold (after sitting for 9+ hours during the work day), started it up, and was able to take it off choke and did a handful of "test launches" within maybe a minute of startup, and it performed quite nicely. I then let it warm up a few more minutes, and try tweaking on the air screws to see if anymore improvement could be had, and it really seemed pretty happy where it was, so I just left it. I didn't really even try messing with the fuel screws anymore, cuz the inner ones (especially #3) aren't the easiest to get too. I just set them at 3/4 of a turn and went with it.

Like I said, I'll see how it is the next time I cold start it, but I think it's pretty good.

 

[maro]

can we also not forgot that the GS'S ARE in fact cold blooded. Even now in a billion degree heat I have to run the choke for 30 sec to a minute to get her "warmed up" and then ride a couple blocks until I close the choke.

 

[Steve]

can we also not forgot that the GS'S ARE in fact cold blooded. Even now in a billion degree heat I have to run the choke for 30 sec to a minute to get her "warmed up" and then ride a couple blocks until I close the choke.

Using the "choke" for 30 seconds to a minute does not really qualify as "cold-blooded".

The original poster gave the impression that he has to run his bike for about 10 minutes before he can even think of riding, then has to be very careful, feathering the clutch, etc., for a few more minutes. THAT is "cold-blooded" and is easily fixed.

All of the bikes in my stable are easily started with about half "choke" or less.
All of them can be ridden within 30 seconds of starting on any day that is warm enough to ride (I typically ride down to about 35 degrees ).
All of them have carbs (no fuel injection) that are somewhat properly adjusted.

Even now in a billion degree heat ...

If I have told you once, I have told you a MILLION TIMES, ... DON'T EXAGERATE.

.

 

[centeno711]

just wanted to add my .02

My bike was cold blooded as all get out.....obviously some difference as mine is an 82 but i recently rejeted it with a dj kit and now it fires right up and idles with a touch of throttle or half choke. This would have been unheard of before..I am totaly happy now, just a little tuning on the mix screws and a more appropriately sized jet and walah.

 

[don]

Before I resurected my 83' after sitting in my parents' garage for ten years, mine would need to run on the choke for 5 min or so before I could even think of touching the throttle. If I didnt start it for 6-7 hours, even in the summer, I'd need the choke.

After I did the work to get it running again after it's long rest, it will start without the choke in the late spring-and summer but I have to keep it going with the throttle for about 1 min. Then it will stay running by itself. Though only at like 500 rpm untill it warms up. But I can ride it right away.

No mods of any sort. Just cleaned and tuned the carbs.

 

[ptomkrvr]

parts Question

parts Question

If the "rebuilt" carbs included the shoddy imitation crap found in rebuild kits, you may need to install OEM jets, needles, etc. to get it running right.

With that said, no, there's no reason at all your GS should be cold-blooded. With stock intake, carbs, and exhaust in good shape and the idle mixture properly adjusted, it should fire instantly and warm up in seconds in any weather.

Of course, any modifications to the intake or exhaust require rejetting, and any deficiencies, air leaks, etc. MUST be corrected. Sounds like you're running quite lean with the modified exhaust, and need to rejet before you do serious engine damage. What color are your spark plugs?

Have you seen the carb kits from z1enterprises, if so, whats your opinion? I'm going to break down my carbs. to see what kind of shape they are in. I'm hoping I just need O rings, but that kit does look nice. thanks

 

[1_v8_merc]

When i first got my bike, took damn near 20 minutes.
Hadda turn it on and off a few times.

After a buncha maintenance and riding.
It only takes around a minute or less to ride off now!

 

[waterman]

Have you seen the carb kits from z1enterprises, if so, whats your opinion? I'm going to break down my carbs. to see what kind of shape they are in. I'm hoping I just need O rings, but that kit does look nice. thanks

Sorry for the threadjack, but it seems to have run its course.

Ptomkrvr,
Not sure what bike you have, but for the vast majority that I have worked on, simply changing out the orings after a thorough dip in carb cleaner usually is the best treatment for carbs. The actual carb parts don't tend to wear out and are usually of better quality than the ones you will find in the carb kits. Plus they are the correct size which the carb kits may not be.

Nice thing about orings is they are very reasonably priced and sourced from a member here named Robert Barr, his website is http://www.cycleorings.com/ and he ships very quickly. He is too modest to post up his own site here, but I am a very satisfied customer and can't say enough good things about his work. I have used 5 kits from him and likely will need a couple more soon.

Please don't take this as a knock on Z1, they also provide a great service and have good products. In this case, you most likely will be better off with just the orings.

 

[Guest]

Cold blooded

Cold blooded

When I picked up my 2005 GS500F at the dealer, the guy there told me the 500's are cold blooded and I would have to choke it to start. No throttle . And warm it up 2 or 3 minutes. It will cough and sputter if I try and take off without warming up. With the 1980 GS1000 I pull the choke to start, push it back in and its ready to go. Maybe the emission junk on the 500 makes it cold blooded.