How to clean 3 holes under butterfly

[conquest87tsi]

My bike was popping when coming off idle and I thought it sounded like one of the right side cylinders. I disassembled the carbs and sprayed carb cleaner through the air jets on all carbs. Sure enough, on #3 very little comes out of the 3 holes under the butterfly. On the other carbs a nice stream is seen when I spray through the air jet. I have been poking in the holes with a bread tie for an hour an the same thing. I have used carb cleaner and the aircompressor, nothing. I really don't think soaking them will help if compressed air won't do it. You guys have any tricks or ideas?

[Ken Talbot]

Your best bet is to remove the carbs and strip them completely apart for a proper cleaning. This is the only way you can really get to every spooge-filled orifice and passage. You may be surprised how many little hiding places there are!

It may be a bit intimidating the first time you do this, but there's lots of good tips to follow in the tech section, and you can always come back to the group for advice and encouragement.

[James England]

Your best bet is to remove the carbs and strip them completely apart for a proper cleaning. This is the only way you can really get to every spooge-filled orifice and passage. You may be surprised how many little hiding places there are!

It may be a bit intimidating the first time you do this, but there's lots of good tips to follow in the tech section, and you can always come back to the group for advice and encouragement.

+1 on that. A proper clean is the best way. I've just done exactly that and the filth in the nooks and crannies of the carbs is quite surprising.

A very important point is to use the correct screwdriver blade size when removing the jets. Brass is brittle and the jets are often very firmly stuck in the carb body. The blade of the screwdriver should be the entire width of the slot in the jet and not loose in the slot. If you use too small or too thin a blade, there is a risk of cracking off some of the brass on either side of the slot and this will cause quite a headache. I used a grinder to make custom-sized blade ends. When attempting to unscrew the jets, I put the carb body on the floor and hold it between my knees, then make sure to push hard down on the screwdriver. You don't want the blade 'riding up' in the slot, because you aren't pushing it hard enough, because this can also damage the slot, making jet removal very difficult. On one occasion, despite these precautions, a slot broke and I ended up having a nervous breakdown ,( successfully and luckily) drilling it out......

Carb stripping may appear daunting but the way to look at it is that it's basically the same thing, multiplied by four. When I first tried it, I did one carb at a time, reassembling entirely before moving on to the next one. Then I wasn't faced with loads of bits at the same time and panicking.

Read up on the carb rebuild thread. The other thing to be very careful about is removing the float pin from the cast alloy 'legs' inside the float bowl. No tapping of the pin or excessive force or the leg may snap. I always use a pair of wire snips under the flange of the pin and this gets them moving. Same goes for putting the pin back..no tapping. I use pliers with one jaw on the flange of the pin and the other jaw behind the alloy leg.......

Check the diaphragms whilst you're at it and hold them over a flashlight to see if there are any pinholes or tears or dodgy creases...

[trbig]

OK, Guys... So how have you helped answer his question? You've now made a lot more work for him, gave him the possibility of stripped screws and broken float posts, and still not addressed his question. He's found the problem, and a completely stripped carb is no easier to clean the 3 holes in question.. unless you want him to remove his butterflies as well?

Conquest, for the tiny orifices, I've taken very thin sewing needles and bent them to almost a 90 degree angle and was able to poke around in there pretty good. But be careful, many needles are brittle and will just break when you try to bend them. Keep everything wet with B-12 while you're poking around. Hope this helps.

[BA80]

My bike was popping when coming off idle and I thought it sounded like one of the right side cylinders.

Is it popping through the exhaust or the intake?

[James England]

Oh, the possibility of broken off sewing needles is an improvement? And poking bent needles in the holes is highly likely to enlarge them.

Holes block for a reason....merely cleaning them out with a a Boy Scout sewing kit won't do any long term good if the carbs are full of crud. The problem will simply recur at some point, sooner or later.

Do it properly...strip them and clean them out. Snap a bent needle in one of them and you'll be stripping them anyway...

[BA80]

Oops...............

[trbig]

James, you've obviously never done what I suggest as you obviously have no idea of what you're talking about or the method as to what needs done. You don't jam bent needles in with a hammer and crash around neanderthal-like. You don't use enough force to break a needle, and if the needle withstands bending to the almost 90 degrees, a small circular motion cleaning isn't going to affect it.

You also fail to realize that these holes aren't such a metered orifice like a main fuel jet. Though I wouldn't go reaming them out with a drill, a cleaning won't hurt to get loose what may be stuck in there.

Maybe you have better fuel up where you're at, but I find it absolutely pointless to clean a set of carbs to the point you gents speak of. Make sure all the passages are clear, and run fuel filters, and within 2-3 tanks full, you'll have a layer of red silt in the carbs here.

Yes, holes block for a reason. Mostly it's sit-itis and bad fuel. Many times, it's a calcium like deposit that I can only assume is from moisture.. something no amount of cleaning will prevent. A bent needle you can lift out if broke is much preferred to a broken float post or stripped idle adjustment screw any day of the week. With all your bad moods aimed at me, you've still yet to offer the gentleman a way to clean the 3 small holes. Tearing them apart to stripped carb bodies will do nothing for that.

Anyone have some help or suggestions as to HOW TO CLEAN THE 3 SMALL HOLES IN THE INTAKE BELL? Not how to do a total carb refurb... 3 holes. It's like telling someone to split the cases to replace the crank bearings, and grind the gears while they're in there because they asked how to replace a crank seal.

[trbig]

So how about this hypothetical question then, James. Say someone has a set of carbs broken down to bare bodies. Say they've been cleaned and fit for eating off of, yet one of the carbs has the 3 little holes stopped up by some sort of obstruction and normal spraying carb cleaner and air doesn't dislodge said obstruction. Then what?

Answer this, and you might just get to the question originally asked.

[Ken Talbot]

OK, Guys... So how have you helped answer his question? ......He's found the problem, and a completely stripped carb is no easier to clean the 3 holes in question......

You have a point there, although I would suggest that he has really only found one problem.

I've always found it easier to get those three holes clean by having the carbs sitting on my workbench and opened. If nothing else, this lets me point the plastic tube on my can of carb cleaner onto the holes and blow the other way than they normally flow. This can be done without removing the butterflies, which as you note, can be a recipe for disaster.

FYI - when you want to bend a sewing needle or pin to 90 degrees for poking around, heat it to redhot in the flame from a lighter and it will bend without snapping.

[James England]

So how about this hypothetical question then, James. Say someone has a set of carbs broken down to bare bodies. Say they've been cleaned and fit for eating off of, yet one of the carbs has the 3 little holes stopped up by some sort of obstruction and normal spraying carb cleaner and air doesn't dislodge said obstruction. Then what?

Answer this, and you might just get to the question originally asked.

Keep your hair on, as we say to unnecessary ire or unpleasantness this side of the pond.

If the guy himself (as opposed to you) finds it all too much, I'm sure he'll point that out himself. In the meantime, proggling about carburettor holes with bent pins isn't what I would advise under any circumstances, especially to someone who is inexperienced and whilst the carbs are actually still on the bike. Yep, you're entirely correct, this is not something I've ever done myself........

[trbig]

So... Still nothing to offer in the form of the guy's problem, James?

The needle thing is the same technique I use on completely clogged jets on that little orifice in the carb bowl as well and it has always worked. Many use tiny pieces of wire to do the same job, but this hasn't worked as it's too flimsy if the obstruction is particularly calcified.

I've tried to give the guy advice with ideas that have worked. Your idea gives him prettier carbs with still stuck holes under the butterflies. You've offered no actual help to the problem on this thread, merely criticism.

My hair is just fine though, thanks.

[BA80]

I think all of you just have a hole fixation.

I personally think the problem with the popping is being caused by a problem elsewhere. Most likely in the ignition since as stated there is some flow through the fixation. errr......I mean holes.

[mharrington]

Just my 2 cents on cleaning small orifices, I take a bicycle brake cable and unravel a strand- or two. Bendable and durable. I clean the tiny hole on brake master cylinders with the same thing.

[mack]

Three holes

The best way to get at those three holes is by removing the diaphram and enrichement circuit plunger. If you look into the big hole in the diaphram housing with a flashlight you'll find that there are several passages interconnected in that chamber immediately behind the idle screw tower. You can get more force to the spray by appling directly to that manefold and placing the tube into the holes directly. Once you have lots of carb cleaner in there. Put the plunger back in and make sure it's in the closed position and put your finger over the idle tower hole then put your compressed air through the small brass pick up tube that fits into the carb bowl. Watch your eyes but you will feel a blast of air through the three holes. Those holes are meters of a sort. Don't stick anything in there that will distort the holes. If you have to, use steel lake trout fishing line. It is flexible and small enough to probe with but it's not a staright run into those holes from above. There is a small chamber immediately above them which will want to bend the wire if you push too deep.