Hi everyone,

So I know that carburetor bikes suck when starting from a cold start and get nice when they heat up, but I'm looking for some advice from folks who are familiar with the GS500 warming up.

Choke
Is choking necessary for the GS500f? I hear that it sucks to warm up in winter, but I live in Hawaii and still get a bit of rough riding. In fact, if the bike isn't warm, it'll just straight-up die when I go into 1st and try to ride off. I think it's probably impossible to start the GS500 cold... so how long should I choke for to get optimal riding? And should I pull the choke all the way?

Rough Riding
When I'm riding it, I seem to get rough riding. It's not an electrical thing. What I mean is that I'll be holding the throttle steady in 1st or 2nd, but I can feel the bike hesitate then go then hesitate then go... so I get a micro whiplash effect going. This issue definitely disappears when I'm riding fast, but very evident on low gears. Today, I rode it for 30 minutes, took a 1.5 hour break, and it is still rough riding in low gear. Is this possibly a valve clearance issue?

WOuld love some insight. Thank you.

Could be clogged idle jets...  I know when mine were dirty, its rough riding.  The holes are tiny and can easily get clogged.  Try cleaning the carbs out and see what's in there.

I also rejetted recently and my warm up time is a lot shorter (but I don't really warm up too much, just for about 60 seconds then drive slow for the first couple lights, warms up faster than just sitting there...).

After cleaning the primary fuel jets in my 89, I have none of the problems you describe. My driveway is a 10 foot climb in 80 feet and I can do that with no choke as long as the weather is warm. The bike is a little lean for about 1-2 miles but nothing that is really annoying. All with no choke applied. I'll see what this winter brings on, but my experience would indicate it will need some choke below 60 degrees F. 60 MPG ain't bad either.

regards
Mech

Clogged jets... that makes sense.

Never thought about it. I guess it's been so long since I've had jets clogged (~7 years) that I've totally forgotten about what it feels like.

Well thanks guys. Guess I'll be fooling around with my carbs this weekend.

Oh the joys of buying a used bike... 

i found this!! ... probably slightly overkill for a GS500 ... but it would look Cool 

http://www.f1technical.net/forum/viewtopic.php?f=4&t=9362

... wups ... forgot... i'll full choke to start cold (which runs it at 3500rpm) and leave it on for 30-60 seconds mostly... then dump it off.... that usually is enough .. coldcold weather and all!

My 93 always needs about 1-2 miles of choke to warm up and not stall, unless I start like under an hour after it has been ridden last.  I know my jets aren't clogged, because they are brand new.  I think after searching around it seems like it's not that uncommon to require the choke, but maybe I am wrong.

On my 02 I usually fire it up on full choke and wait til the RPM goes up to 4k. I then kinda give the choke a bit of the ol' gentle touch and find a happy place where it sits around 3k. Put on jacket. Strap on backpack. Mess with choke a bit more to keep RPM around 3k, put on helmet, gloves, put choke down to a minimum amount, just enough to keep the bike idling around 1.5k and take off. Usually flip the choke the rest of the way off at the first stop I make. Overall, quite a cold blooded beast but I have a system down now. Takes about 3 minutes from initial start up til I leave.

Some people just let the thing rev to between 4 and 5k for a couple minutes and are good to go (if I understand their posts). This does work for me but working in a machine shop and knowing how metal changes shape with heat, I just can't bring myself to do that.

This process will probably be changing in the coming weeks once I install a slip on. Loud pipes may save lives but they are pretty annoying to just having revving at 3k for 5 minutes at 6 or 7 am.

Quote from: ndlsjk on August 28, 2013, 09:56:11 PM
On my 02 I usually fire it up on full choke and wait til the RPM goes up to 4k. I then kinda give the choke a bit of the ol' gentle touch and find a happy place where it sits around 3k. Put on jacket. Strap on backpack. Mess with choke a bit more to keep RPM around 3k, put on helmet, gloves, put choke down to a minimum amount, just enough to keep the bike idling around 1.5k and take off. Usually flip the choke the rest of the way off at the first stop I make. Overall, quite a cold blooded beast but I have a system down now. Takes about 3 minutes from initial start up til I leave.

Some people just let the thing rev to between 4 and 5k for a couple minutes and are good to go (if I understand their posts). This does work for me but working in a machine shop and knowing how metal changes shape with heat, I just can't bring myself to do that.

This process will probably be changing in the coming weeks once I install a slip on. Loud pipes may save lives but they are pretty annoying to just having revving at 3k for 5 minutes at 6 or 7 am.

This is the same procedure I follow, pretty much! I try not to let the bike start and sit around 4K when I first start it. I usually blip it a bit at the start and control it down to 2K. Put my back pack on, then raise it to 3K and put on the rest of my stuff. Wasting a bit of fuel is nothing compared to wasting the engine over time.

My bike was awesome. Carbs were jetting and tuned. They were also synced. Valves were in spec and with those Brisk spark plugs, just as soon as I hit the starter button it would fore to life. I never had to use choke

On a cold day I gave my 97 GS full choke when starting and walked away to put on helmet, gloves, etc and within a minute or so it was starting to race away and I had to get to it and close the choke some to bring it down from 3-4k rpm to below 2k rpm.  It was pretty much the same way for the 4 years and 80k miles I rode it here in NE Ohio.

On the other hand my 02 GS would/will start up on a cold day at a similar 13-1500 rpm idle as the 97 but it never speeds up as it warms.  In a minute or so it begins to bog down with decreasing idle and will die if throttle is not opened or choke closed some in time.

That and other considerations indicate my 97 with the older 2 circuit carbs was considerably leaner running than my current 02 GS is with the newer 3 circuit carbs.  Both bikes have gone all the way for the 177k miles I've run them with completely stock carbs.  I think both were/are normal.  The 02 still runs as good as new if you disregard the high oil consumption at high speeds after you get higher milage on them.  Somewhere between 50k and 80k miles the 500cc GS engine changes into a 500cc oil pump.   

After closing the garage and climbing back on the GS I repeatedly blip the throttle sharply while adjusting the choke slowly down to a point as low as I can and still crack the throttle open sharply without bog.  It really takes less than a minute and after having done it for so long it's done now without thinking about it which is a blessing for a man of my age.

I've always been able to ride off on the 02 able to open the throttle as much as I wanted to as soon as I'm out the drive and on the street and it never dies at the stop light down the block or the stop signs at the next two blocks.  It's time to close the choke completely after the stop light if I remember.    

Both my GS's have had completely stock untouched carbs all the way for the many years and miles I've used them, never even saw the need to sync the carbs since I never tore them apart.

Quote from: weedahoe on August 29, 2013, 05:50:41 AM
My bike was awesome. Carbs were jetting and tuned. They were also synced. Valves were in spec and with those Brisk spark plugs, just as soon as I hit the starter button it would fore to life. I never had to use choke

And I've never lived in South GA weeds riding year around for the past 29 years here in NE Ohio in temps down to 20F.  We choke them here!   

I used the choke on my GS 3 times. All 3 times it was 40 degrees and she still fired pretty fast! Even when it was wayyyyy out of tune with valve clearances non existant it would fire on the 2nd crank. Sounds like GS's like the south better 

Quote from: tzzzel on August 28, 2013, 06:35:00 PM
Rough Riding
When I'm riding it, I seem to get rough riding. It's not an electrical thing. What I mean is that I'll be holding the throttle steady in 1st or 2nd, but I can feel the bike hesitate then go then hesitate then go... so I get a micro whiplash effect going. This issue definitely disappears when I'm riding fast, but very evident on low gears. Today, I rode it for 30 minutes, took a 1.5 hour break, and it is still rough riding in low gear. Is this possibly a valve clearance issue?

Doubt it's a valve issue, it's probably a rider issue and if it's what I'm relating too a simple shift will fix it.  Coming back from a ride with engine well warmed up I pull into the far drive and ride past a long line of attached garages at slow speed to listen to the engine.  If I leave it in 2nd gear which I've entered the driveway in I usually feel that mild bucking you describe but a downshift to 1st and it's smooth all the way as I listen to the rattling jugs 100k miles will give you on a GS.      Downshift isn't always the fix at higher speeds, not high speeds, when you're riding along at a steady throttle and feel the same mild bucking, very mild indeed, your cruising in too low a gear and an upshift a gear will fix it.  If you're felling what I think you are a shift up or dawn is the fix depending on the speed you're going. 

Tzzel - You probably should synch the carbs as well as clean it.
It may still be lean, you cant clean your way out of a lean bike, you have to rejet it ...
Cool.
Buddha.

The things with these bike is they are all different and have a mind of their own. We all have our own ways of warming them up and know exactly what they need. It just time to figure it out, I remember when other people would try to start and ride my bike they would be like "how do you get thing thing to stay on?!"

Also, check to see if your valve clearances are too tight....

Quote from: ndlsjk on August 28, 2013, 09:56:11 PM
On my 02 I usually fire it up on full choke and wait til the RPM goes up to 4k. I then kinda give the choke a bit of the ol' gentle touch and find a happy place where it sits around 3k. Put on jacket. Strap on backpack. Mess with choke a bit more to keep RPM around 3k, put on helmet, gloves, put choke down to a minimum amount, just enough to keep the bike idling around 1.5k and take off. Usually flip the choke the rest of the way off at the first stop I make. Overall, quite a cold blooded beast but I have a system down now. Takes about 3 minutes from initial start up

+2 and a half! This is a proper way to warm a bike up.

Quote from: tzzzel on August 28, 2013, 06:35:00 PM
Hi everyone,

So I know that carburetor bikes suck when starting from a cold start and get nice when they heat up, but I'm looking for some advice from folks who are familiar with the GS500 warming up.

Choke
Is choking necessary for the GS500f? I hear that it sucks to warm up in winter, but I live in Hawaii and still get a bit of rough riding. In fact, if the bike isn't warm, it'll just straight-up die when I go into 1st and try to ride off. I think it's probably impossible to start the GS500 cold... so how long should I choke for to get optimal riding? And should I pull the choke all the way?

Rough Riding
When I'm riding it, I seem to get rough riding. It's not an electrical thing. What I mean is that I'll be holding the throttle steady in 1st or 2nd, but I can feel the bike hesitate then go then hesitate then go... so I get a micro whiplash effect going. This issue definitely disappears when I'm riding fast, but very evident on low gears. Today, I rode it for 30 minutes, took a 1.5 hour break, and it is still rough riding in low gear. Is this possibly a valve clearance issue?

WOuld love some insight. Thank you.

clean those carbs!

http://www.youtube.com/watch?v=AJh1hxNf7BA&feature=youtu.be

My 89 has never had the caps removed from the low speed adjustment screws. I have the 94 set at 3.5 turns, the caps were removed prior to my purchase.
I start the bike and go, no choke. My driveway climbs 10 feet in 80 feet and I can pull up that grade with a little clutch feathering and about 3k RPM, from dead cold. So far I have not had to deal with winter on these bikes, ambient temps are 70+ F.
It does take about a mile before the lean flat spot is gone, which indicates the mixture is correct. Plugs are beautiful and mileage is excellent.
On the 89, after going through the 94 carbs, I took a gamble and focused on cleaning the low speed jets. Everything else looked good except the float bowls which had some crud on the bottom, which I cleaned up.
Since both bikes act almost exactly the same, I think that is fairly good proof that both setups are running the way they were designed to run.
That being said, I will see how they act in colder weather later this year. My best estimate is I will need some choke when temps drop below 55-60 degrees. Constant velocity carbs tend to need warmer air when cold, but should be fine after a couple of miles.
I prefer to avoid choke use unless it is absolutely necessary. On other bikes when I needed choke I would give them just enough to avoid major hesitation. I do not run my bikes hard cold, generally about 5 miles when the oil starts to warm up nicely.

regards
Mech