83GS550E Bigger Pilot Jets to cure no idle ?

[GQROD]

My Canadian Spec Carbs have OEM supplied 37.5 pilot jets.
NO EPA I suppose?

I do agree that the bike should idle properly if the carbs are clean and have had no alteration to the carbs though. If it does not then it never could have.

Hey calvin have you ever taken out your Pilot Air jets to see what number they are? and what pilot jet number they are matched to? just out of curiousity, since i had an issue with this on my carbs and resolved it to some respect with Melodic's help.

[Calvin Blackmore]

Hey calvin have you ever taken out your Pilot Air jets to see what number they are? and what pilot jet number they are matched to? just out of curiousity, since i had an issue with this on my carbs and resolved it to some respect with Melodic's help.

Oh Man I had them out a while back and never looked. I can look on the weekend when I get home.

Again I assume that the Canadian Spec bikes and likely also non-California bikes would have run richest.

Forgive me but you have shot carb celaner through all orifices and got a decent and equal flow for each respective circuit?

I seriously thing the problem is elsewhere if the the carbs are squeaky clean and no one has messed em up with a stel wire for ceaning etc.

alos are the valves adjusted to specification? You seem carb obsessed.

[skreemer]

Skreemer, if the jetting shouldn't be touched, why are there so many different sizes out there? I ask b/c as part of this I have recently discovered that out of three sets of carbs, each had different sized pilot AIR jets (145, 150, 155).

I was talking of the pilot fuel jets... I switched to a stage 3 DynJet kit as I had pods and a 4 - 1... I was constantly running rich at idle and lean on the top end after following the instructions.

Constantly reset the air mix screws, changed to the smaller main jets, dropped the needles all the way and I was still way rich on the bottom and now I was scorching lean on the top...

Reset everything again... dropped the needles, went back to the proper mains, tightened down the air mix screws (literally bottemed em out and had to replace them). I still was way rich on the bottom and now only lean in the middle and fine on the top...

On a whim I pulled the pilot jets out and checked the sizes against all the documenttion I had... found out somewhere along the way they were switched from 35s to 37.5s... I went out bought the 35s and set everything the way Dyno jet suggests and she now runs like a scalded cat... AND idles the way it should... there's some fine tuning I could do to get it on the ragged edge but she's running awesome....

8 times out of ten the lean condition is something not sealed properly.. loose boots or bad o-rings...


Though to everyone... to "cheat" at the EPA game the bikes are usually set to run slightly lean from the factory...

[Zook]

I was talking of the pilot fuel jets... I switched to a stage 3 DynJet kit as I had pods and a 4 - 1... I was constantly running rich at idle and lean on the top end after following the instructions.

Constantly reset the air mix screws, changed to the smaller main jets, dropped the needles all the way and I was still way rich on the bottom and now I was scorching lean on the top...
<snip>

If you were lean on top at first, why did you go to smaller mains?

You have to get one circuit running right before you can move on to the next.
Pilots-idle to just off idle. Now it can start, idle and putt around.
Needles-off idle to about 3/4 throttle. Where you'll do most of your riding. Transitioning from pilots to midrange smoothly is critical.
Mains-WFO. Hope most of your riding isn't here, but if ya got it, flaunt it!

Don't forget the atomizer jets-you know, the tube with the holes in the sides. These affect midrange greatly.

I posted a tuning guide from Dellorto carbs in another thread that helps a bunch.
Do a site or web search.

[GQROD]

83GS550E won't idle-update part 2

Oh Man I had them out a while back and never looked. I can look on the weekend when I get home.

Again I assume that the Canadian Spec bikes and likely also non-California bikes would have run richest.

Forgive me but you have shot carb celaner through all orifices and got a decent and equal flow for each respective circuit?

I seriously thing the problem is elsewhere if the the carbs are squeaky clean and no one has messed em up with a stel wire for ceaning etc.

alos are the valves adjusted to specification? You seem carb obsessed.

Yes i am carb obssesed-lol, after four months of rebuilding carbs, waiting for jets, and finally getting it all back together not to mention the money spent on carb tune, color-tune, jets, gaskets etc:, waiting yet another ten days for each in between only to find nothing works can be a little trying on the nerves.

1-Yes i did a meticulous rebuild per this forums suggestions. Chem dipped, spray cleaner, fishing line through all orifices etc.

2- O-rings new oem suzuki.

3-Valves adjusted to highest allowed measurement of .13mm both intake and exhaust valves.( thanks again to Basscliff for valve adjusment tool help of using square head deck screw into a wooden dowel-pure genious, worked great ).

4-NOW ONTO SOME GOOD NEWS..... Finally got it to idle .....

4a-Full choke-engine raced to 3000 rpm, shut it down.

4b-Moved lever to half choke position-started right up!! Petcock in Run position.

4c-Let engine idle for 17 mins, after 5 mins took off choke, and made three idle speed adjustments to get it to idle around 1200. Engine stopped after 17mins.

4d-Re-started right away, idle speed adjusted to 1100 rpm, idle fluxuated between 800 and 1300 rpm. died off after 5 mins.

4e-Re-started instantly, idle adjusted to 1400 rpm idle held. Died off after five mins.

4f-Re-started instantly let idle between 1100 and 1500 before it died after another five minutes.

5-So at least it idled long enough to do idle speed adjustments, i will look at the plugs when it cools a bit even with mechanics gloves it's too hot.

6-I did not blip the throttle or race the engine so i can get a clear idea of what the mix looks like when i pull the plugs.

7- I hear wd40 is not good for finding air leaks, just in case i'm missing something is thee a more effective way of finding air leaks?

thanks again everyone for your help its making progress!

[p_s]

Does the idle slowly move around or do you hear a hesitation and a choppy idle? If so, try pulling the headlight fuse and see if it changes. I don't think this is your problem but I had a sticky idle on my 550ES in May that turned out to be the slides getting stuck. Do they close smoothly on their own?

[GQROD]

Does the idle slowly move around or do you hear a hesitation and a choppy idle? If so, try pulling the headlight fuse and see if it changes. I don't think this is your problem but I had a sticky idle on my 550ES in May that turned out to be the slides getting stuck. Do they close smoothly on their own?

Yes the slides move freely. I did think of this but when i took them apart i could move them easily and they came right back down and i'm not aware of a lubricant for tthe slides. I know wd40 won't work it makes teh slides get stuck in open position, unless a dry lubricant with graphite would do the trick but i have not tried it.

The idle actually goes up and down slowly meaning it stays at a given rpm then steadly goes up stays there then goes back down to a low of about 700 rpm.

I did not test it without the headlamp fuse in but this makes a lot of sense since the battery would be drained by the headlamp during idle if it's not being charged at this slow rpm.

1- Well i took out the plugs and they are all white, obviously lean.

2-Took the bike out for another spin. Idles high at 2000 at stop signs, had to turn the idle speed down at the stop sign.

3-Since the plugs are lean i will be going to bigger pilots as mentioned and see if this solves the problem along with testing the charging system, but at least it starts right away now and will idle well enough to do plug chops under load.

I will keep everyone posted, thanks again for your help.

[MelodicMetalGod]

GQROD,

Haven't seen an update in a while. What's the scoop? Hopefully the lack of posting means you're up and running and riding too much to have time to post...?

[Carter Turk]

Could your float height setting be too lean?

[GQROD]

Thanks for the interest !

I have not posted because i have had the #37.5 pilot jets soaking in carb dip they were all blocked so i want to make sure the inside crud is soft enough to come out without damaging the inside diameter.

So far it starts right away with new choke cable, and will warm up fine.

However it will still have a high idle as i have run it a couple of times around the block.

Constant idle speed adjustment is still necessary and it will not hold a steady idle under 2000 rpm for long before it steadily dies.

I have read here and on other maufacturer sites that this condition may indeed be pilot jets are too small so i'm going to install the #37.5's then colortune to see if this helps. I may have to order #40 jets if this is still too lean though.

I still have to check the charging system just could not find my multi-meter.

I will keep everyone posted when i have results that show some progress,
thanks again.

Float height was set at 20.5mm using vernier calipers, i thought about this but i did not want to mess with the float heights. When i set the height it did seem to be perfect within factory specs which was higher than they originally were. Fuel flow to bowls is excellent due to new pet cock, so i wanted to try the jets first then if this fails try the float height adjustment.

[doctorgonzo]

My wandering idle has reappeared after I pulled carbs to replace a body. I think mine is sync, very possible yours is too. Last time I snyced it cured this issue.

[tone]

A couple of things come to mind, i'm assuming the bike is stock here so correct me if i'm wrong

most bikes will run slightly lean at tickover
i've experianced this particularly on us spec bikes with the emission control bull attached, binning any such rubbish & setting the carbs to uk spec improves the running enormously
colourtune does not give a true reading on the new fuels
guessing at pilot jet sizes will lead you into a world of problems

to clarify that last statment swapping pilots from stock is for racers where a nice even tickover or clean transition on to mains is not important, ive run highly tuned road bikes with major mods to induction & exhaust & never needed to swap them yet

air leak & either worn emulsion tubes or needles is where i'd start to look also check the float heights & for damaged diaphrams or worn slides, are the carb vent tubes still present ?

hope it helps

[GQROD]

A couple of things come to mind, i'm assuming the bike is stock here so correct me if i'm wrong

most bikes will run slightly lean at tickover
i've experianced this particularly on us spec bikes with the emission control bull attached, binning any such rubbish & setting the carbs to uk spec improves the running enormously
colourtune does not give a true reading on the new fuels
guessing at pilot jet sizes will lead you into a world of problems

to clarify that last statment swapping pilots from stock is for racers where a nice even tickover or clean transition on to mains is not important, ive run highly tuned road bikes with major mods to induction & exhaust & never needed to swap them yet

air leak & either worn emulsion tubes or needles is where i'd start to look also check the float heights & for damaged diaphrams or worn slides, are the carb vent tubes still present ?

hope it helps

Thanks for the advice, yes bike, carbs,airbox,exhaust all stock, diaphrams are all good no holes, slides have very light vertical scuff marks but move freely.

1-I synced the carbs with a morgan carbtune when i first put them on after the rebuild should they be synced again?

1a-You are correct about the need to worry about a smooth transition as this thought crossed my mind.

2-Carbs rebuilt to stock specs which for usa are leaner than most countries which is why i considered going up one size on the pilots.

3-No air leaks, installed oem new orings, carb vent tubes ( hoses?) still present. well it has one the other is missing should it have a hose? not shown in factory manual.

4-I checked the emulsion tubes and needles when i pulled the carbs and did not notice an " out of round " situation on the tubes and needles were stock and in good shape, not bent or anything.

5-In response to Carter Turk's suggestion( good point by the way)-Would anyone/everyone agree that i should change the float height before changing the pilot jets? Also why does the float height change the mixture? i thought the float height was merely for fuel level in the bowls?

thanks

[GQROD]

Update on pilot jet installation.

SHE FINALLY IDLES !!!! though not as long as i'd like......

1-Installed #37.5 Pilot jets an increase over the #35's that were stock spec.

2-Finally was able to set the idle at 1100 rpm, idled for almost an hour with only a slight lumpiness of +/- 100 rpm.

2a-NO MORE high idle hanging up !!!!!!!!!!!!!!!!!!!!!!, comes right back down to 1100-1200 rpm idle speed no matter how many throttle blips !!

3-Mixture screws were adjusted two more turns out from 1 1/2 originally set with color tune on cylinders 1 and 2, cyls 3 and 4 show richer than than 1&2.

4-This time i set the mix screws just reading the plugs during idle, they are finally a light tan to dark brown i'm still fiddling with the mixtures and adjusting for a richer mixture as needed, re-setting the idle speed as i went.

5-Transition is smooth from idle to WOT !!

6-However-it does still die at stops after a 20 min high speed run, headlight on. I have not tested the charging system yet but i believe now that the charging system may be faulty and this is leading to the bike dying at stops.

7-I think the battery is being drained, while idling for almost and hour the engine died and there was not enough juice to start the bike, so this is the next task.

7a At what rpm exactly does the stator start to charge the battery?????

7b-Also i started to hear a RATTLING noise coming from the lower left side of the engine, after about 10-15 mins while it was already hot it stopped then returned after a few minutes what is this ???????

8-Thanks again everyone for your help and suggestions i'll keep you posted.

[MelodicMetalGod]

Right on...congrats!

I assume that if you're idling the bike for long periods of time (an hour? yikes!), that you've got a fan pushing cool air over the engine? If not, I think that you want to do so. After an hour, the lack of air cooling could allow damaging levels of heat to build up.

Regarding charging at idle: I don't know for sure, but I've always been under the impressiong that most bikes, unlike most cars, do NOT charge at idle. Therefore, I'm not at all surprised that after an hour of idling the battery was spent. That said, I don't know what RPM these bikes start to generate enough juice to start recharging the battery. Of course, it's common knowledge around here that the charging systems on these bikes are their achilles heel to begin with even before accounting for the troubles that can come with the sheer age of the systems.

As far as your rattle sounds goes, I have no specific ideas on that one. Hopefully somebody will pipe up with some ideas.

Sounds like you've still got some work ahead of you, but I'm glad that you're making progress and you can now at least take the bike out for some extended test (joy?) riding.