Looking for ideas and solutions. Please help if you had similar problems. - Page 2
Close
    
    
Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 26
Like Tree31Likes

Thread: Looking for ideas and solutions. Please help if you had similar problems.

  1. #11
    Senior Member GaryL's Avatar
    Join Date
    Jun 2013
    Location
    Forestburgh, NY
    Posts
    7,805
    Quote Originally Posted by GNolan View Post
    Gary,
    The jet I call the Main jet is in the center of the Bowl and guides the needle. The Pilot jet is inside the bowl. The Idle jet is external from the bowl and adjustable. I have an O-Ring on the Main Jet and on the Idle Jet. It sounds like you call it the pilot jet and I call it the idle jet. I never saw an O-Ring on what I call the Pilot Jet.
    You are half right Greg. I never said the pilot JET which is inside the float bowl. I did say the Pilot SCREW which is outside and forward of the float bowl and between the cylinder head and usually has a protective plug over it so you can't adjust it until the plug is pulled. Part number 4 in this diagram.
    https://www.partzilla.com/catalog/ya...00m/carburetor. Part number 39 is the little plug that needs to be pulled out.
    Smitty Blackstone likes this.
    Be Decisive! Right or Wrong just make a decision. ​ The road of life is paved with flat squirrels that couldn't make a decision.

    Since light travels faster than sound, some people appear bright until you hear them speak.
    If I agreed with you, we'd both be wrong.

    1987 Yamaha BW350 Big Wheel
    2017 Snowdog Track sled tow motor for ice fishing
    Kubota BX2370 Subcompact tractor with snow blower
    Wilderness System Ride 115 fishing Kayaks

  2. #12
    Senior Member elime's Avatar
    Join Date
    Jul 2010
    Location
    San Jose, CA
    Posts
    6,897
    Check the rubber intake manifold. Sounds like a big vacuum leak to me.
    GaryL and Smitty Blackstone like this.
    Long live the internal combustion engine!

  3. #13
    Junior Member GNolan's Avatar
    Join Date
    Feb 2019
    Location
    Clarkston MI
    Posts
    18
    Gary,

    Ah. Ok. got it. So you say Pilot Screw and I say Idle screw. Thanks for that. There is an O-ring on the Main Jet and Pilot/Idle screw. I will check the intake manifold and will probably soak the carb again. It's got to be something stupid and/or I'm the stupid one. But it is just the same way as I found it. I was very careful. I did not check the float dimension. Not sure what the spec is and how to measure. I may eventually try a Mikuni VM26-606 Carb and a new CDI module from TomB.

    Thanks for your help and to anyone else that can share any experience.

    GNolan
    Smitty Blackstone likes this.

  4. Remove Advertisements
    TW200Forum.com
    Advertisements
     

  5. #14
    Senior Member GaryL's Avatar
    Join Date
    Jun 2013
    Location
    Forestburgh, NY
    Posts
    7,805
    Quote Originally Posted by GNolan View Post
    Gary,

    Ah. Ok. got it. So you say Pilot Screw and I say Idle screw. Thanks for that. There is an O-ring on the Main Jet and Pilot/Idle screw. I will check the intake manifold and will probably soak the carb again. It's got to be something stupid and/or I'm the stupid one. But it is just the same way as I found it. I was very careful. I did not check the float dimension. Not sure what the spec is and how to measure. I may eventually try a Mikuni VM26-606 Carb and a new CDI module from TomB.

    Thanks for your help and to anyone else that can share any experience.

    GNolan
    Greg, I call it the pilot screw because that is the name Yamaha calls it. Best if you study the diagram I sent you here and call the parts the name they use so there is no confusion in the future. If you notice part number 22 is called the Throttle screw set which is how you set the idle once the carb is running correctly and I would call that the idle screw if I didn't know the correct term. The Pilot screw number 4 is actually your adjustment for the air to fuel ratio and you can lean the carb out or richen it up with that adjustment but it must be adjusted after the engine is at full operating temp. Most of us have found that between 2-2 1/2 turns out is about right so we say bottom it in all the way and turn it back out 2 full revolutions and then a 1/4 turn more to start. From that point it might need a slight tweek either way to get your carb purring through all throttle positions and gears. You might feel a slight buck at full throttle or a slight stumble while cranking on it which tells you it needs a tiny turn more or less. The rubber boots on both sides of the carb absolutely must have a perfect air tight seal. Check that while the engine is running at idle and spray some WD 40 or other not real flammable spray around the seals. If the engine revs different when you spray you have a leak. Let me add one additional caution. Some might tell you to do some other upgrades like different jet and shimming the needle. These tweeks can have some beneficial effects in some cases. Never do any such changes until you have the carb working correctly to begin with. Then and only then if you want to try to eek the very last bit of performance from it at least you know the carb was right before you did the changes. I have been perfectly satisfied with the performance once I got the carb tuned right so I don't mess with jet sizes and shims but others here are very happy with those upgrades once they get them dialed in and they are good if you are in very high altitude areas. I hear good reports about TomBs CDI modules but I never try to fix things that are not already known to be faulty. It is always best to go one step at a time and one system at a time when you are fighting with gremlins. If you disconnected the rectangular block on top of the slide there is a very tiny spring that goes inside of that block and in between the two posts that go through it.

    GaryL
    Fred, Xracer and Smitty Blackstone like this.
    Be Decisive! Right or Wrong just make a decision. ​ The road of life is paved with flat squirrels that couldn't make a decision.

    Since light travels faster than sound, some people appear bright until you hear them speak.
    If I agreed with you, we'd both be wrong.

    1987 Yamaha BW350 Big Wheel
    2017 Snowdog Track sled tow motor for ice fishing
    Kubota BX2370 Subcompact tractor with snow blower
    Wilderness System Ride 115 fishing Kayaks

  6. #15
    Junior Member GNolan's Avatar
    Join Date
    Feb 2019
    Location
    Clarkston MI
    Posts
    18
    "If you disconnected the rectangular block on top of the slide there is a very tiny spring that goes inside of that block and in between the two posts that go through it."

    Not sure what you are referring to here. Can you try with other words. I did not remove the slide. I removed the slide housing cover so that I could inspect/clean it. I did not change the needle. I reused the OEM jets after cleaning.

  7. #16
    Junior Member GNolan's Avatar
    Join Date
    Feb 2019
    Location
    Clarkston MI
    Posts
    18
    I am thinking like what Smitty Blackstone posted. Also, yes, I am just trying to get the stock OEM carb right, at this time. I hear you on that one.

  8. #17
    Senior Member GaryL's Avatar
    Join Date
    Jun 2013
    Location
    Forestburgh, NY
    Posts
    7,805
    Quote Originally Posted by GNolan View Post
    "If you disconnected the rectangular block on top of the slide there is a very tiny spring that goes inside of that block and in between the two posts that go through it."

    Not sure what you are referring to here. Can you try with other words. I did not remove the slide. I removed the slide housing cover so that I could inspect/clean it. I did not change the needle. I reused the OEM jets after cleaning.
    Shown as part #3 in the diagram. It is a connecting link on top of #20 valve, throttle they call it a bracket. If you did not disconnect it then don't bother. My first TW had the carb rebuilt by a dealer shop before I bought it and it did not run good at all. I yanked my hair out trying to get it running right with no success. Bought a brand new carb that worked perfect out of the box. Then I sat at my dining room table and took both the new and old carbs apart piece by piece. The new factory carb had the tiny spring inside the bracket block and the dealer rebuilt carb had the tiny spring on top of the needle set #19 and in the absolute wrong place. The lesson I learned there was just because some jack wagon dealer mechanic rebuilt the carb before I got it does not mean he knew what he was doing. The guy sold me the bike because he could never get it to run right even after spending stupid money for the dealers top mechanic to go through it. I got the spring where it belonged and it purred like a kitten. Trust yourself and no one else and don't ever assume the guy who fingered it before you knew what he was doing. We have a great member here named JBfla who was my personal guru on the old style carbs and he got me straight. He has some great pictures in the technical write up section on the very top of this tech section. There are a few others here who can rebuild these old style carbs with their eyes closed so everything you need to know is at your finger tips in the TW200 forum.

    GaryL
    Xracer and Darth like this.
    Be Decisive! Right or Wrong just make a decision. ​ The road of life is paved with flat squirrels that couldn't make a decision.

    Since light travels faster than sound, some people appear bright until you hear them speak.
    If I agreed with you, we'd both be wrong.

    1987 Yamaha BW350 Big Wheel
    2017 Snowdog Track sled tow motor for ice fishing
    Kubota BX2370 Subcompact tractor with snow blower
    Wilderness System Ride 115 fishing Kayaks

  9. #18
    Junior Member GNolan's Avatar
    Join Date
    Feb 2019
    Location
    Clarkston MI
    Posts
    18
    Hello Gary
    I took a fresh look at my TW project. I set out to remove the carb again to have the MC Shop clean the carb body. I discovered that I did not have the intake mounting clamp tight (thanks Smitty). Before tightenin, I double checked the mixture screw and set at 2.5 turns. I started up and after a short time was able to push in the choke and have it idle. Rough but did idle. At one point it seemed like something let loose in the carb and it then idled even better. As I went along I was adjusting the throttle stop. The idle seems to be on the high side but if I came down on the idle with the throttle stop, it would want to back fire through the carb. Then I put the air filter back in it and this seemed to help the idle even more. Without experience with this engine I really don't know just what to expect. All in all it was very positive progress.
    I did notice a problem. While at idle, I goosed it a couple times. Response was good but I noticed that the engine did not return to idle right away. Almost like a car with an anti decel solenoid on it. Seems to me that it should have just dropped right back to idle quickly. Is it typical for these engines to behave that way? On we go...
    GaryL likes this.

  10. #19
    Senior Member Gastone165's Avatar
    Join Date
    Dec 2017
    Location
    Western Washington
    Posts
    191
    Get a parts diagram and take apart your carburetor piece by piece. Verify everything is present and where it’s supposed to be. You may have a misplaced, missing, or damaged part and never know it unless you do. With the parts diagram its pretty simple and straight forward.
    Just like GaryL, I purchased a 2002 TW that was in great shape but idled strangely and ran poorly. I dissected the carb and found the little spring on the top of the needle was missing. After I replaced the missing part it now runs great.
    GaryL likes this.
    1972 Yamaha DT 175, 1974 Kawasaki 125, 1976 Suzuki TM 250, 1979 Yamaha 750, 1977 Husquvarna 360, 1979 Husquvarna 250, (2) 1980 Suzuki RM 400’s, 1971 Husquvarna 400, 1983 Honda V65 Magna, 1987 Suzuki 230 Quad, 1987 TW200, 1990 TW200, 1996 Honda XR 650, 1998 Yamaha 300 King Quad, 2000 Harley Davidson Heritage, 2006 Kawasaki KLX 250s, 2007 Arctic Cat 650 Quad, 2010 Polaris Sportsman 850 Quad, 2006 Yamaha Grizzly 660 Quad, 2002 TW200, 1995 TW200, 2008 TW200, 2016 TW200.

  11. #20
    Junior Member GNolan's Avatar
    Join Date
    Feb 2019
    Location
    Clarkston MI
    Posts
    18
    Gastone
    Yeah. I see that spring. It looks like it keeps the needle seated. Otherwise the needle would float somewhat and could rise causing the idle delay. Thanks for that good information. Gary stated that but I did not study the parts diagram well enough. It makes sense.

Page 2 of 3 FirstFirst 123 LastLast

Sponosred Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. Replies: 37
    Last Post: 11-15-2017, 07:25 PM
  2. Tw 200 vs similar bikes - opinions please
    By Deepseadan in forum General Discussion
    Replies: 25
    Last Post: 10-19-2016, 05:16 AM
  3. Replies: 16
    Last Post: 12-12-2015, 04:47 PM
  4. Replies: 55
    Last Post: 02-18-2015, 08:56 AM
  5. Replies: 3
    Last Post: 12-12-2014, 07:49 PM

Tags for this Thread