Jetting When Carbs Are Not Consistent

[wbshee]

Here's the scoop. I had a TORS removal installed.

 

After getting it back I realized I wasn't satisfied with the sync. One side idled nicely while the other side would just idle half ass. IE: You can hear the consistent firing from the side that seemed to idle well, and you could tell from feeling the exhaust it was firing every time and had good pressure. The other side however would fire about half or less of the other it sounded like, and feeling the exhaust confirms it.

 

Now, I looked at the carb sync. The idle kit screws are nearly all in on both. You know how the air needles come to a point on each, well it looks like the slides are making contact on the part before it actually starts to taper, where the needle is the thickest (highest idle). I look at this by looking through the air intakes on both.

 

I figured it was prolly air screw jetting, however, the screws when turned in all the way are not the same distance inwards. I think there is a stubborn spring on one or something. For instance, I can turn one in much further than the other.

 

Everything runs great at every other throttle than idle and just barely giving it any, which would mean my issue resides in the pilot circuit, right?

 

So I am curious, does it sound like I am jetted too rich (the air screws need to come out more?). When I had them install it, I could tell they never adjusted the air screws after removing the tors. And I had been playing with these damn screws before.

 

Anyways, like I said, I think I am perfect on all other throttle positions above idle. How do I go about syncing these carbs when the air screws do not seat at the same position when tighten down? Can I try to measure from the small little air intake that runs past the pilot?

 

Does it make sense my idle would be all the way turned in (slides resting on the non-tapered, thickest part) and I still have idle problems?

 

How would you guys troubleshoot this if this were you? I'm not even sure if it is lean or rich at this point. I just know it doesn't idle properly on both cylinders, and that it has a slight bog when you barely give some throttle. I'm thinking rich, but could lean also produce a similar bog?

 

Thanks!

[Banchetta]

To adjust the air screws, just turn them all the way in (seated) then turn them out =. I have mine 1 turn out from seated.....To sync the idle screws: make sure whoever installed the tors removal kit had filed the side of the carb enough. You have to take off about 1/16-1/8" off the side of the carb. If not, then the idle screw won't go in far enough....Once thats done, look into the intake and turn the idle screw in slowly until the slide moves very little, now do this to the other side. Start it up and adjust the idle = to both sides...

[wbshee]

Here is the problem though. One screw seats in much further than the other, so simply counting the turns provides no accuracy. I can visably see the screw on one side seated inside of the hole, whereas when the other screw is seated it is barely flush with the hole.

 

I have an idea of how I am going to troubleshoot this. I am going to start with the carbs idled all the way down and sync them up.

 

I will then put the air screws all the way in as well. To make sure I can count turns I am going to remove them until I can see the ends through the air screw intake hole. I will then count the turns in on the side that doesn't seat as well. I will reproduce those turns on the side that does seat well.

 

I will then keep starting up the bike and checking for bog when barely giving any throttle. I will adjust the air screws out in matching turns until bog is eliminated. I will then check the idle, and bring the idle up on both until she idles correctly.

 

Doesn't it sound odd my idle is cranked all the way up, yet it doesn't idle high. I would think this indicates a currently rich condition on the pilot circuit. However, right now I am working with about 2 turns out on the screws.

 

FYI: T-5's, K&N w/ outters, rest pretty stock. Temps in 70-80's during day, about 500ft above sea level, running 310 mains, 4th clip position, and not sure what pilot I am running.

[wbshee]

Wow... syncing cylinders is about the most frustrating thing in the world.

 

I cleaned both carbs again while I hard them off. Still clean from before but what the hell. I got the idle screws and air screws set exactly on both carbs it looks like. The carbs themselves are sync'd, in terms of the slides.

 

Despite doing all of this the two cynliders are not running in harmony at and around idle throttle.

 

I now have a couple questions that hopefully I can get answers for:

 

1) Is it normal or acceptable for carbs to be adjusted differently between the two. I feel like my left cylinder is running rich, while the right seems to be about where it should.

 

2) What could cause different conditions between the two? I but a new gasket on the intake manifold/boots. The carbs are cleaning than when they come out of the factory. What else? If I am searching for an air leak, what is the best way to check? Can I spray starting fluid around the boots and check for increased rev? I've inspected the boots and they look good though.

 

Here's my current observation. I kick it over no prob, and I give it rev and both sides keep up nicely. When I start to let it idle down, the right side stays up pretty well, though it has a slightly high idle (don't think it is lean, or it would rev higher/faster probably, and not at a consistent pace). The left side however stops firing, and I think it is just sucking in fuel and not burning. If I left it run like this for more than a few seconds, it becomes nearly impossible to get the left side firing again unless you let it sit for a while, because I think it floods the cylinder from it sucking in fuel w/o burning it.

 

Bottom line, considering the right side is running correctly, is it safe to say I am rich on the left side? Unless I were EXTREMLY lean, I should have combustion even at a lean condition. The fact that if one side is running properly, and the other side isn't running, and is very difficult to getting running at any throttle after that would suggest it is flooding, right?

 

I put in brand new plugs, and I have only ran the engine for like 15 mins off an on adjusting things, they haven't really started to color up much.

 

I will try to post pics of them shortly for opinions.

 

Thanks!

[BenBB]

Yes, look for an air leak using starting fluid (ether), while it's idling, around the carb boots and tops; if it idles higher you've found the leak.

 

One thing to consider: without the TORS you use the cable adjusters on the carb tops to synchronize the slides, and the idle screws to set the idle speed. If you synch the carbs with the idle screws there's a chance that one carb will open off idle before the other IF there's slack in the cable itself. Doesn't sound like that's your problem but thought it was worth mentioning.

 

My first inclination is to see what the plugs look like, that'll tell you if one side is richer than the other. If the old ones are gone or didn't tell you anything, try letting it idle on the new plugs for about 15 minutes and see what they look like. You should be able to tell if one is richer than the other, or way too rich/lean.

 

Next, you might double check the compression just in case.

 

Last, see what size the pilots are. You could probably use 30 pilots, assuming your plugs don't read that it's already too rich. Another thing, if you haven't already try removing the airscrews completely and clean/compare them to each other, it's odd that one goes farther than the other. Good luck.

[Banchetta]

Ben is on it... also how does it run if you just turn the air screws all the way in and then out equally?? Try turning them 2 turns from fully seated...does it run evenly?? It is odd that one is out further. Never seen that...Take the air screw out and blow compressed air in there or maybe even probe it, maybe there is a grain of sand in there or something.....the pilots sound a little rich...check them out..I'd drop them down a size. I like my air screws to be optimum around 1 turn out for best throttle response. Being 2 turns out, tells me that your pilot could very well be too rich.