Hesitant acceleration after carb cleaning

[Nerobro]

Oi.

Your mechanic is an idiot. The stock jetting is just fine on a GS550 with the airbox in place. He should not have rejetted. All your bike needed was to have the pilot jets cleaned and the mixture screws cleaned.

Did he tell you what jets he installed? If he didn't, you're up the creek untill you find out what he put in there.

What prompted you to file your points? By filing them you have changed the timing of your bike. Your timing will need to be reset now.

Right now, you need to clean, and reset your carbs back to their stock settings. (this is REALLY Easy to do.) And make sure your timing is set properly. This isn't 30-60 hours of work, it's more like 3-6. You'll be amazed when you see just how simple it really is.

[ShirleySerious]

He didn't give me too many specifics, but I can try to repost what he wrote on the order sheet.

"Cleaned & synced carbs, cleaned points and set timing, replaced tires & tubes, changed oil & filter, replaced plugs, checked brakes, adjusted & lubed chain, checked cables, checked & adjusted clutch, checked exhaust & air filter"

It looks like an overall thorough job, at least on paper. He jetted it because I have pods, not the stock airbox.

[tkent02]

Go talk to these guys.....

http://www.suzukicycles.com/Products/CategoryDisplay.aspx?id=B3447AC7-BFAE-4AD3-A7EB-82C9A299EA45

I don't have the patience to learn how to fix it myself. Sorry, that's just how I am.

They have lots of nice bikes for people who don't care to know how they work.

[Kcwiro]

That was perhaps a little harsh.....but on an older bike you are worth learnign to be your own mechanic...or at least know enough to ask the kind folks in here for a hand after using the 'search' feature :-D

I can understand you may not want to spend the time to learn... I bought my bike this last year... I have been doing my own rebuild on it this entire winter...started out to fix the oil leaks...ended up needing an entire overhaul, cleaned carbs, de-rusted *as best I could* gas tank..new fuel lines...replaced exhaust...list goes on...

anyway...idea is I have learned more in the last few months than I knew I was capable of understanding...if you have the desire to learn, put in the time... you may not get it right the first time but big deal... you try.. make mistakes learn and move on.

I'll be extremely satisfied with myself knowing when my bike comes back to life *hopefully this month* it will be the result of the hard work and effort my friend and I have put into it.

Good luck to you

[paco13]

I'm not sure which hose was left unconnected, but this could be most of the problem. Start the bike and put your finger over the exposed nipple. If it draws vacuum this is your prob. Then you have to find where it connects on the other side and hook it up. Do you have a vacuum operated fuel petcock? Are they the nipples on the manifolds for carb sync.? Or might be just vents.

Also, did you have this prob before you brought it in? Were the pods on before or did they install? If they installed them, even if they did rejet the carbs I highly doubt they got it right without test-ride. this would cause your symptoms also.

[KSlawman]

This sounds ghetto, but try it anyway. Take some duct tape and wrap about half of each pod so that only half of each one is exposed. Take it for a ride and see if it cures your problem. It will restrict some flow, and cause your lean problem to go more rich. Try it, what are you out if it does not work. I say you are flowing too much air.

[ShirleySerious]

I talked to Nerobro tonight and he thinks it's OK that my vent tubes are gone, as long as I'm running pods. Since the bike was running fine last summer and the problem I was having while the bike was in storage just needed the carbs to be cleaned, if the mechanic rejetted it, it was totally unnecessary.

Tomorrow I'll ask the mechanic about the specifics of the job and what he did with the jets. IYO, if he screwed it up, do you think I am entitled to at least a partial refund?

So yes, I did cave in and invested in a Clymer manual. For someone who's never worked on anything like this it is very intimidating. It's just tough to work on a bike in a cold, poorly lit garage with few tools.

[ShirleySerious]

I managed to snap some pictures of my setup. Sorry if they look like crap:






Pic 1:Carbs on the right side
Pic 2:Looking left where the vacuum tubes used to be
Pic 3:Boots w/ carb sync screws looking left
Pic 4:Left side carbs, choke & petcock(Blurry, I know)

I know it's difficult to tell what's wrong by just looking at, but it might help. KSlawman, I tried the duct tape thing, but that didn't work.

[KEITH KRAUSE]

So the thread title is accurate? After the carb cleaning the hesitation began? If so, you describe fuel starvation. Your engine needs less fuel to rev in neutral than under load. If I remember correctly, a plug read also looked lean?
The fuel starvation could be the carbs or flow related, possibly as simple as a kinked fuel line or cracking vacuum line.
When you run pods with your VM carbs, the two floatbowl vent lines must be removed to avoid fuel starvation. The mechanic at least did that right. I've made many posts about removing the vent lines when running pods if you want to search and read.
Hard to say what the mechanic did to result in this problem. If he did try a complete re-jet of all 3 circuits, we'd have to know what jetting he chose and if he used Mikuni jets and the correct style. Example: there are two lengths of Mikuni pilot jets for your carbs. Install the wrong/shorter one and it will run poorly. Generally, todays mechanics don't know how to jet our older bikes or service the carbs right.
I also don't like the sound of "filing down the points", though it can be beneficial if done right. It does sound like the carbs are adjusted wrong though.
If you don't feel comfortable doing the work and your mechanic isn't able to work on it, I don't know what you do. It's not that hard to work on the VM carbs but you do need to get a factory manual and basic tools to do it. Then ask us lots of questions.
I can give you some initial jetting suggestions that may be right the first time but jetting for pods and a stock exhaust can take some time. The pods will require at least one position richer on the jet needles and the jet needles are the most work on your carbs.
Just real hard to say what's needed until the carbs are inspected and all current jetting info is given.
Like I said, it's possible the carbs are jetted OK but it takes plug reads at different throttle positions and more performance/symptoms given to be sure. It could be as simple as adjusting the pilot fuel screws and side air screws correctly.
If you feel comfortable adjusting the screws, try it. Record/count their present settings and you can return them there if you don't like the results. Typical settings for your carbs would be 1 3/4 turns out for the side air screws and about 1 1/4 turns out for the pilot fuel screws underneath. Though fine tuning would be needed, these initial settings would be fairly close and if set that way, any problem as you describe wouldn't likely be from poor screw settings.
Just be careful if the screws are stiff to turn. Use a good fitting tool and a mirror to accurately record the settings. Always seat the screws LIGHTLY and then adjust out as I said. You may be lucky and it runs much better without any inside carb work. Set the idle to about 1,100 rpm's when warmed up. Tell us if the idle rises noticably from cold to hot.
I wonder too if the carbs were vacuum synched. That could contribute to poor performance.

[ShirleySerious]

I found a repair manual online, which isn't really convenient because I can't bring it in the garage, but it'll do for now. I checked the pilot air screws and they were all seated. I screwed them all out 1.5 turns, but I'm still having the same problem. I may be able to work on it tonight once I take a look at the manual, but probably won't be turning it on, as I've ****ed my neighbors off enough.

I'm not really that concerned about working on it myself, I'm just weirded out by all those fuel lines and taking off the gas tank because one wrong move and I've got gas all over.

[KEITH KRAUSE]

I checked the pilot air screws and they were all seated. I screwed them all out 1.5 turns, but I'm still having the same problem.

If the side air screws were seated, then the mechanic truly doesn't know what he's doing.
Also, there's no way that your bike could hold anything close to a normal idle rpm if the side air screws are seated. Impossible. Without holding the throttle open, it would stall immediately. Starting would be very difficult too unless you throttled it. Even then, difficult.
Any chance you actually mean the pilot fuel screws underneath?? The bike would run if these were seated but you would be running lean unless the mechanic installed larger pilot jets and he found it necessary to close the pilot fuel screws. Again, that would be the work of a poor mechanic.
Please verify what screws you turned 1 1/2 out.

[ShirleySerious]

If the side air screws were seated, then the mechanic truly doesn't know what he's doing.
Also, there's no way that your bike could hold anything close to a normal idle rpm if the side air screws are seated. Impossible. Without holding the throttle open, it would stall immediately. Starting would be very difficult too unless you throttled it. Even then, difficult.
Any chance you actually mean the pilot fuel screws underneath?? The bike would run if these were seated but you would be running lean unless the mechanic installed larger pilot jets and he found it necessary to close the pilot fuel screws. Again, that would be the work of a poor mechanic.
Please verify what screws you turned 1 1/2 out.

My bad. I can't tell the difference, so here's the picture with the screw I adjusted circled. I'm not sure about the others, so I circled and numbered them (I know, I'm stupid). It's #1 in the pic:

I have a feeling you are talking about the pilot screws because it doesn't stall after adjustment, but you can definitely tell it's doing something.

[49er]

Shirley, make sure that you disconnect the earth/negative strap from the battery before removing the gas tank. If you should accidently short out on the positive with a spanner of screw driver, you could be meeting your maker earlier than you've planned.
Seriously though, you've done the right thing buying a manuel. Take your time and keep asking questions. We'll eventually get you hanging on for dear life, through all the gears.

[ShirleySerious]

Please, call me Josh (that's my real name).

Secondly, thanks for the advice. I'm not taking the tank off anytime soon, though. The aft part of the tank is loose, held down by its weight and the seat, but I can't figure out how to remove the fore part.

Anyway, the manual I downloaded wasn't all that great. It was kind of old and didn't really explain how to do things so well. I bought a Clymer manual. Is that a good one?

[49er]

Okay Josh.
The aft of your tank should be secured by a bolt passing through a rubber doenut. This setup helps reduce foaming of the fuel, caused by vibration. It is dangerous to leave your tank floating around like yours is. The seat is the only thing preventing it from detaching from the bike.
When/if you do need to remove your tank, disconnect your petcock fuel line, vaccum hose and the fuel gauge electric leads. Now lift the aft end about 3 ins, slide the tank rearward for about another 3 ins and then lift the whole tank upwards. The front is held in position by two rubber bushes (another vibration reduction setup), which disengage with the tank when slid backwards.