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Discussion Starter #1 (Edited)
For those that have followed any of my recent posts -

My bike, a 2000 with the Teikei cylindrical slide carb, was running perfectly and started instantly until I replaced a deteriorated air filter with a new properly oiled one. Then my troubles started. First I couldn't start the bike, then when I got it started it ran terribly so I added some Berryman's B12 to the fuel in an attempt to a quick and easy carb cleaning., and it also put out white-gray smoke when I finally got it started and running. It wouldn't run without choke. I thought the carb may have gotten some filter debris in it so I took off the carb and cleaned every orifice. No change. I emptied the fuel tank thinking the Berryman's could make the smoke, refilled with fresh gas, put in a new plug (the other one was black and wet - fouled). Then I replaced both the pilot and main jets (on my bike, stock is 40 and 114 and that's what I put in). The smoke I figured out was gas in the oil, maybe coming back in via the airbox. checked and the level was up, and I also had some oil in the airbox below the filter, so I drained the oil and replaced it and again took the carb apart for thorough cleaning #3. The bike ran pretty much the same - it would take forever to start and run. It would run for 2 secs. then 3 secs, eventually 15 secs., then would run steady. minimal smoke. And again the oil level increased due to gas leaking in. I have a hard time believing the float needle was leaking because I couldn't blow through it with the carb upside down, but today I took the carb apart for the 4th time. I cleaned again every orifice, every little piece of the carb. I got the pivot shaft for the floats out without any difficulty but when I put it back together I replaced that shaft with a slightly smaller diameter nail trimmed to the right length so I can get it out again without the fear of breaking off one of the posts. The O ring on the needle seat looked good. The rubber diaphragm in the enricher circuit is intact and clean with no rips or tears. All the new jets are clean and patent. After I put it all together again I hooked it up to the fuel tank, left the petcock open for an hour and there's not a drop of gas leaking out of the bowl overflow drain or anywhere from the carb. The pilot screw is turned out 2 turns and I don't know what it's supposed to be for this carb. Now the bike starts easier, no smoke, runs only with the choke on either full, or when warm down to half choke. It falters/hesitates on acceleration, then takes off by itself and runs well at high speed. It dies if I turn down the choke. No smoke and no increase in oil level now. I tried to open the pilot to 2 1/2 turns, but that makes no difference, and isn't that only for starting or low speed?
I also checked for air leaks around the carb to engine connection by spraying carb cleaner in the area and that has no effect.
So. I have some questions.
I never leave the petcock to ON when the bike is off, so how does gas get into the oil when the engine is running? A leaky float needle would allow that to happen when the bike runs?
Am I running rich or lean, because of the hard starting, bad acceleration and inability to run without at least half choke (enricher), and how would I know and how do I fix this?
The thing that ticks me off in all of this, aside from taking this all apart so many times and not fixing it, is that it was perfect before I replaced the air filter and that should not have caused any of this.
Thanks for any suggestions.
 

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It's lean and it sure sounds like the idle circuit. Do you have a fuel filter in the gas line? It may be getting slime right back in it immediately from the bottom of the tank. How old was the gas that was in it when you first started it? Wash the tank out. Start over re-clean it. Pull the jets and use compressed air in through all the circuits, use a ultrasonic cleaner if you can get one, soak it with the jets out if not. That your float kept sticking letting gas through the air box is a clue you have/had bad gas. The idle circuit is extremely sensitive to bad gas in the TK's
 

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Discussion Starter #3 (Edited)
OK. so I let it sit for maybe 3 hours leaving the petcock ON, no increase in the oil level, no gas on the floor under the bike.
I started it eventually after 15 tries before it would run for more than a second or two., and had it running for 3-4 min. A little bit of smoke on startup and running moderately high throttle on half choke. Won't run on no choke. Now oil level has gone up over the top of the site glass. Why does that happen while running, when it doesn't leak gas when bike is off and the petcock is left ON?
And I just cleaned it for the 4th time - every passage can be easily blown through with carb cleaner and air so I don't know what else to clean after taking the entire thing apart 3 times and doing the same thing.
How do you fix "lean"? Is the cylinder not moving up and down with the throttle? Not likely, as I can see it move on the bench, and I can find no evidence anywhere of air restriction. I have also again squeezed out the air filter to make sure of that. It runs the same with filter on or off.
 

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If sitting and the float bowl overflow tube was plugged I could see the carb filling up and spilling into the cylinder down into the case but only happening while attempting to run or running. Stumped.

I've had a TW carb where the needle seat o-ring had deteriorated. I think you mentioned it was ok but I can't quite tell for sure. I'm not talking about the rubber tip at the end of the needle. I had a very hard time starting mine with this leaky condition but the symptoms are not the same as yours as my enricher would have to be pushed in not out like your problem.

Mine would leak on the ground when off if petcock not turned off and there were signs of engine running and starting problems before complete failure. I was on the trail and the engine died on me. Fuel was leaking out of all the overflow/breather carb tubes not just the float bowl overflow tube.

What I'm saying or thinking out loud is maybe you have multiple problems needle valve seat bad causing leaking even though it looks good (can be cracked and look good) and your float bowl overflow tube plugged.

Only things I can think of.

I have an a 2005 carb which is not in use currently I can loan you if you need a good carb to to help diagnose your problem. Let me know via PM if you do.
 

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You are beyond generous!

If sitting and the float bowl overflow tube was plugged I could see the carb filling up and spilling into the cylinder down into the case but only happening while attempting to run or running. Stumped.

I've had a TW carb where the needle seat o-ring had deteriorated. I think you mentioned it was ok but I can't quite tell for sure. I'm not talking about the rubber tip at the end of the needle. I had a very hard time starting mine with this leaky condition but the symptoms are not the same as yours as my enricher would have to be pushed in not out like your problem.

Mine would leak on the ground when off if petcock not turned off and there were signs of engine running and starting problems before complete failure. I was on the trail and the engine died on me. Fuel was leaking out of all the overflow/breather carb tubes not just the float bowl overflow tube.

What I'm saying or thinking out loud is maybe you have multiple problems needle valve seat bad causing leaking even though it looks good (can be cracked and look good) and your float bowl overflow tube plugged.

Only things I can think of.

I have an a 2005 carb which is not in use currently I can loan you if you need a good carb to to help diagnose your problem. Let me know via PM if you do.
 

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Discussion Starter #6 (Edited)
Float bowl overflow tube is definitely NOT clogged either inside the carb, or the plastic/vinyl tube leading down to below the engine.

Does the newer 2005 carb have the same dimensions as my 2000 carb? I believe it was a different manufacturer and the throttle cables attach on the right side of the bike, mine attach on the left side, and the in and out throat diameters attaching to the boots may be a different diameter. Anybody know? But thanks alot for the offer, I have to investigate further.
 

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Discussion Starter #7
i have a brand new clean jet in there and the passages are wide open. So where in the carb do I look?

Is the carb generating that high a suction it can suck in more gas than is needed and it goes into the cylinder and down pass the rings? How else does gas get into the oil?
And tell me why the bike won't run if the choke is turned down. How can it run lean (too much air, not enough fuel) and pour gas into the cylinders to leak into the oil at the same time?
I'm missing something here.
 

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Discussion Starter #8
I've seen this video before, many, many times, and thanks for it again. The only thing I could imagine is that I still may have a blockage in the air line leading to the pilot jet, maybe a tiny piece of crap from the disintegrated filter that carb cleaner or chemicals won't dissolve or clean out and I may have to take the carb off again to try and get to it.

What I don;t understand is how gas is getting into my oil if the float needle is not leaking. Can there be so much of a venturi effect in the carb if that air passage is blocked off to be able to suck up gas through the enricher circuit and pilot jet in excess, and not get burned, that it gets to seep down into the oil? I can't imagine that. How else can gas get into the oil if not via the cylinder leaking past rings and why shouldn't it just be running rich and burn up that gas?
 

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What I don;t understand is how gas is getting into my oil if the float needle is not leaking. Can there be so much of a venturi effect in the carb if that air passage is blocked off to be able to suck up gas through the enricher circuit and pilot jet in excess, and not get burned, that it gets to seep down into the oil? I can't imagine that. How else can gas get into the oil if not via the cylinder leaking past rings and why shouldn't it just be running rich and burn up that gas?

I'm still thinking something in the fuel circuit is plugged and another part is leaking backing up fuel into the carb and then into the engine through the intake. Fuel is not coming out of the float bowl overflow tube right? This could be true if your float is stuck in the closed position with fuel not flowing into the bowl. With a bad needle seat o-ring, you can still get fuel leaking into the carb thus allowing fuel to overflow into the engine.

I suppose in theory if you are having a massive amount of fuel going into the cylinder through the intake when trying to start and it's too much fuel, as in a type of flooding condition, unburnt fuel could also be seeping into the engine but this would have to be a lot to fill up the crankcase as your describing.

You've mentioned doing almost everything in the below link but maybe it's worth reading to see if it triggers something you haven't investigated.

Carburetors - Dan's Online Motorcycle Repair Course
Dan's Motorcycle "Motorcycle Carburetor Repair "

P.S. my 2005 carb is still being offered but I would also have to send you the intake manifold as it has a different angle than the pre-2001 carbs and I can also send with it the cables and twist throttle.
 

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Sounds like several problems associated with the first "too rich" symptoms followed by the current "too lean" status as well as the reported apparently variable oil level.
I would replace the entire float needle assembly since a worn needle can stick itself to the seat walls in either an open, or closed condition affecting the fuel mix.
Clogged small air passageway(s) that the mixture screw and jet feed into could also account for the current lean state that does not respond to changes in mixture screw settings.
As pointed out any significant amount of gas in the crankcase would have a strong odor. A smell test at the oil fill port should readily confirm or deny gas in the oil.
 

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As pointed out any significant amount of gas in the crankcase would have a strong odor. A smell test at the oil fill port should readily confirm or deny gas in the oil.
Yes
In the days of mechanical automotive fuel pumps, a leaking diaphragm could be detected by smelling the dipstick.
Also, a sample of oil would be ignitable.
 

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Discussion Starter #13
I squeezed the filter between 2 rags so there is no excess oil on it, as I said above, thinking that maybe the oil in my airbox and running rich could have come from that.

My float needle is shiny clean as is its' valve seat cylinder or sleeve (I don;t know what you call that part), and easily falls out if I turn the carb over, so it is not sticking at all.

I took this all apart again, for the 5th time, and cleaned every little nook and cranny and tube and orifice and jet and spent a lot of time doing this, then did it again to make sure, with carb cleaner, probing with a fine wire, air pressure blast, and I don't know how it could be cleaner. I found nothing blocked up, and carb cleaner and air would flow through every passage, even ones I had never known of before.
I took off the crankcase vent hose to inspect it and it's absolutely bone dry and spotlessly clean in there so I have no idea how the oil got into the airbox, my air filter was not wet enough to do that (I don't think).
I have read and seen Dan's articles, read it again, have cleaned many carbs before and never encountered anything like this.
Now the bike runs somewhat better but takes at least 15 tries to get it to start, still runs for 2 secs, then 3, then 5 then eventually will stay running. After a minute or two I can turn down the choke a bit, the bike will run OK then spontaneously surge to a higher rpm, then slow again. I cannot push in the choke more than 2/3 or 3/4 in or the bike will die, even if warm. If it dies, it will restart in 1/2 sec if I do it immediately, but if it sits for a few min I need full choke again to restart it. It makes a little smoke (gray) out the exhaust till fully warmed up and the tailpipe is black inside with oily soot, and the plug is coated black. It responds to the throttle with a little stumble but will rev up to max just fine.There does not seem to be gas in the oil again, at least the oil level is no longer rising like before.
All the literature from factory as well as aftermarket says that my pilot jet for my carb is a #40 and that's what I replaced mine with. Can this all be due to running rich and should I maybe go down one size to #38 pilot jet? My bike ran absolutely great before any of this happened on the stock setup.
All this seems to me that the bike is running rich now, but then why do I need the choke (enricher) to keep the bike running at low speed? Like I said I have gone over the carb multiple times and cannot fathom any place or orifice or tube that could be obstructed.
BTW, I made a little screwdriver tool to be able to get to the pilot jet screw while on the bike because getting to that screw and adjusting it is a PIA as I don't have a short enough screwdriver to access that very well. Mine is now, with the help of a small bench grinder, made out of an old extra Allen wrench which fits in there just right and the angle on it lets you accurately count the number of turns you make. IMG_1801.jpg IMG_1802.jpg IMG_1803.jpg
 

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Discussion Starter #14
After running some Berryman's B12, about 2-3oz. into a 2/3-3/4 full fuel tank, (not really a very high dose), in an effort to possibly clean up anything I could have missed, it's running much better. I can turn the choke completely off and it idles fine. It hesitates on twisting the throttle but once it catches, it will rev up to max and smoothly once you get past midrange. It still smokes, mostly on acceleration and high speed, but less, and I've tried to turn down the pilot air screw but that shouldn't really matter too much. Maybe now some of the smoke is from the Berryman's but that would probably be wishful thinking. I'm going to let it sit for another day, soaking in it's B12 mix, take another look at and clean up the plug tomorrow and try it again. To me it's running rich even though it's got the original spec jets, and there's no air restriction anywhere.
It's still a bitch to adjust that pilot air screw underneath the carb, easier to do with the carb on it's side but then you can't do it while the engine's running. Got to make myself another shorter screwdriver.
 

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FYI on the pressed in float pins pick up a 3/32 drill bit I get them with the octagon shank meant for makita etc cordless drivers and just using your fingers and a drip of oil you can ream out the pressed in pin tower so the pin will be free floating retained by the float bowl. I have to rotate back and forth kinda like a tap and die but it’s safer than using a drill and possibly having it bind and break the tower. Also I’ve repaired broken float pin towers with JB weld but be sure to ream out the hole so you don’t put any more strain on it
 

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I’d replace the pilot again which I had to do on two dif bikes this week it’s the single most critical part and nothing works right unless that pilot is pristine clean

throw away the berrymans the sea foam and any other miracle in a bottle fuel additives they are all counter productive

if anything get some non ethanol premium ethyl and her sister Alice if they still work at the gas station those two sisters can clean out anything
 

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Discussion Starter #18
FYI on the pressed in float pins pick up a 3/32 drill bit I get them with the octagon shank meant for makita etc cordless drivers and just using your fingers and a drip of oil you can ream out the pressed in pin tower so the pin will be free floating retained by the float bowl. I have to rotate back and forth kinda like a tap and die but it’s safer than using a drill and possibly having it bind and break the tower. Also I’ve repaired broken float pin towers with JB weld but be sure to ream out the hole so you don’t put any more strain on it
I'll remember that 3/32 drill bit if I ever have to take off the carb in the future, but hopefully I'll never have to do that again.
 

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I’ve read quite a few cases on here where aftermarket jets from rebuild kits have not performed as well as OEM (not saying that’s what you’ve got). Jets R Us seems to have good stuff, but I don’t have first hand experience with any others.

Now that you’ve got it running somewhat better, you might want to try some fine tuning on the air-fuel mixture screw. I believe with new jets, even if they are same specs as OEM, tuning might make a difference.

When you originally changed the air filter, was your bike coming out of storage and hadn’t been run in a while? Or did you have it running fine with the old setup right before the change?

Hope you get it setup to your liking soon. Cheers
 

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Discussion Starter #20
The bike was used, ridden at least once a week, ran absolutely perfectly before I replaced the air filter.
I would have expected the new jets I got would at least be bored out to the specs they claim.
I am still playing with the pilot air mixture screw but have to come up with a screwdriver I can use so that it can be adjusted with the bike running.
 
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