Stumped with 1992 TW200 starting issues - Page 2
Close
    
    
Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 29
Like Tree25Likes

Thread: Stumped with 1992 TW200 starting issues

  1. #11
    Senior Member kennethshaw's Avatar
    Join Date
    Jan 2011
    Posts
    170
    So I fiddled more with it last night and got it to start and idle (albeit weakly). Things I did included: 1. Removed all shims. 2. Confirmed stock jets are in (40 slow, 114 main). 3. Turn air mix screw out 3 turns. Started without choke and when I pull the choke, it still dies immediately. Also, as soon as I touch the throttle barely, the bike dies.

    Things I'm wondering about. If I pull the choke, doesn't that richen the fuel air mix? It seems counterintuitive that I would need to turn the air mix screw out so much to richen at idle but pulling the choke kills the bike. I am going to check for air leaks tonight by spraying starter fluid around the carb boots and see if that causes the idle to change.

    GaryL: I did actually replace the needle valve set. As for the diaphragm set, I verified that it was there and that the plunger behind it was able to be depressed. Would that affect idle and initial roll on of the throttle?

    I'll keep fiddling this week with it and look into CDI removal and troubleshooting as well. That part #1 is looking better by the day.

  2. #12
    Senior Member GaryL's Avatar
    Join Date
    Jun 2013
    Location
    Forestburgh, NY
    Posts
    7,911
    Quote Originally Posted by kennethshaw View Post
    So I fiddled more with it last night and got it to start and idle (albeit weakly). Things I did included: 1. Removed all shims. 2. Confirmed stock jets are in (40 slow, 114 main). 3. Turn air mix screw out 3 turns. Started without choke and when I pull the choke, it still dies immediately. Also, as soon as I touch the throttle barely, the bike dies.

    Things I'm wondering about. If I pull the choke, doesn't that richen the fuel air mix? It seems counterintuitive that I would need to turn the air mix screw out so much to richen at idle but pulling the choke kills the bike. I am going to check for air leaks tonight by spraying starter fluid around the carb boots and see if that causes the idle to change.

    GaryL: I did actually replace the needle valve set. As for the diaphragm set, I verified that it was there and that the plunger behind it was able to be depressed. Would that affect idle and initial roll on of the throttle?

    I'll keep fiddling this week with it and look into CDI removal and troubleshooting as well. That part #1 is looking better by the day.
    That pilot screw adjustment is a tricky little bugger. Why are you going so far out with it to begin with? We all say set it between 2 full turns out and some go to 2 1/2 full turns out to find the sweet spot. If I turn mine out to 3 full turns the engine will stall and not re start. Set it at 2 turns out and get the bike running if it will. Allow the engine to come to full operating temp and then and ONLY then can you do the final fine tune which should be in between 2 and 2 1/2 turns out. I believe the diaphragm is a deceleration circuit which keeps the carb from backfiring but if the plunger is stuck or the rubber is cracked the bike will run very rough.
    I have purchased 3 brand new OEM old style carbs simply because these carb issues drove me nuts. It is a royal PITA pulling the carb off and putting it back on so many times. When the new carb arrives I yank the plug over the pilot screw and set it at 2 full revolutions out from bottom. Once the bike is running and hot I can then set the final fine tune. All three new carbs performed perfect right out of the box. I went so far as to have the old and new carbs side by side as I opened them both to compare and be sure I did not have some part wrong in the old one. Sure enough I had a tiny spring in the wrong place and my float was not set right. Fixed that and the carb worked perfect. Shims and different jets might be fine if you are riding in high altitude or looking for every last drop of power but they must be done in a known working carb that is running the bike fine to begin with.

    GaryL
    Fred 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

  3. #13
    Super Moderator Purple's Avatar
    Join Date
    Mar 2015
    Location
    Ynys Môn
    Posts
    4,472
    May seem silly - but have you checked the air filter ?
    (Warning - Forum may contain nuts) ...... Hidden Content

    TW200 - 1998 - Japanese import - 7000 miles on the clock - TW225 Special Edition 2007
    - Hidden Content

  4. Remove Advertisements
    TW200Forum.com
    Advertisements
     

  5. #14
    Senior Member kennethshaw's Avatar
    Join Date
    Jan 2011
    Posts
    170
    Purple: I will check that definitely tonight. Do you simply remove the side cover on the left side? I did that last night and all I see is a metal screen. Should there be some sort of paper filter or foam behind the black side cover?

  6. #15
    Senior Member GaryL's Avatar
    Join Date
    Jun 2013
    Location
    Forestburgh, NY
    Posts
    7,911
    Quote Originally Posted by kennethshaw View Post
    Purple: I will check that definitely tonight. Do you simply remove the side cover on the left side? I did that last night and all I see is a metal screen. Should there be some sort of paper filter or foam behind the black side cover?
    Part number 11 here, https://www.partzilla.com/catalog/ya...-tw200m/intake. It is an oiled foam air element. All of this is working against you. The entire intake through the carb has everything to do with how well the bike will run. With no filter element in there you are barking at the moon to try to set the air to fuel ratio going into and through the carb. Also be sure to inspect part #7 which is up under the seat behind the battery box. I have seen mice build nests there and even had one member used that area to stuff a hand wipe rag not realizing he was cutting off the air intake flow.

    GaryL
    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

  7. #16
    Super Moderator Purple's Avatar
    Join Date
    Mar 2015
    Location
    Ynys Môn
    Posts
    4,472
    Behind that metal screen, as Gary says, is a foam filter, that has to be oiled to work. Too much oil, and it stifles air flow, too little, and it won’t catch the dust particles. Recommendation is to buy a new one, as the existing one is likely toast by now. Soak it in oil (there are a few products out there, but basic 20W oil will do it), wring it out as much as you can, place it back in the frame, and put the wire mesh back over it

    I’d recommend researching the principle of how this type of filter works, which will give you a greater understanding of what’s involved. What is second nature to some, but not be to you – start here https://www.mishimoto.com/engineerin...d-air-filters/ - but don’t stop there. Research it until you’ve got your head around it

    Gary’s next suggestion is just a valid – if you lift off the seat, you will see that there is an air vent under there that acts as a “snorkel” for deep water crossings. This air vent beneath the seat leads down to the air filter chamber, which is a favourite nesting place for all sorts of critters – make absolute sure they are clear of any and all obstructions. It may not be obvious at first, but it is there – find it, and clean it out

    Again, until you have done this basic stuff, you do not have a starting point for your problem (although I suspect this will cure a lot of it)

    If you don’t know something, ask – there’s no such thing as a dumb question on this board ………
    (Warning - Forum may contain nuts) ...... Hidden Content

    TW200 - 1998 - Japanese import - 7000 miles on the clock - TW225 Special Edition 2007
    - Hidden Content

  8. #17
    Senior Member GaryL's Avatar
    Join Date
    Jun 2013
    Location
    Forestburgh, NY
    Posts
    7,911
    In the very first post Ken said this, I've resurrected a number of these tw200's but this one has me scratching my head.

    Every engine requires Air, Spark and Fuel for it to run correctly. In searching for these gremlins it is most important that we begin with some of the basics. Make sure we are getting air, make sure we are getting fuel and make sure we are getting spark. Ken's bike does run, just not very well so he is inside the carb. We already know from his statements he is using a fuel supply outside of the tank. We already know the engine gets a spark and will run but yet to be determined if the spark is right. Now for the air induction part of the equation. Air comes from under the seat and behind the battery box and flows through the air box chamber through an oiled foam filter before it gets to the carb intake side. The seals, called Joints or rubber boots must be air tight. The filter element must be present to accomplish the correct air flow volume and the air intake must not be clogged or impeded in any way so this means check it from top to bottom. The carb itself works off a vacuum produced by the piston and valves which suck air and fuel through it. No air or no fuel or no spark and NO GO. It makes no sense at all to be inside the carb before you know what the other systems are doing or even if they are functioning as designed. Once you know for sure it is getting Air, Fuel and Spark with no leaks or impediments along those routes you can then go inside the carb to chase internal gremlins. These bikes don't run well if any of these systems are not working as designed.
    There are other possible gremlins which I doubt here but we have also heard of the previous owners doing a valve adjustment and adjusting them 180 degrees out by not having the piston in the right stroke when adjusting valves. There are good tutorials on adjusting the valves here also. With only 192 miles I seriously doubt you have to go any further than checking the basics and I seriously doubt your CDI has any issue. Your bike is 27 years old with 192 miles and that is around 7-8 miles per year for 27 years. Bad gas, dirty carb, dry and hard boots and critters in the air box is my complete assessment from where I sit.

    GaryL
    littletommy 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

  9. #18
    Senior Member kennethshaw's Avatar
    Join Date
    Jan 2011
    Posts
    170
    Purple, GaryL: I think Purple may be onto something. I noticed that there was no foam filter which would assume that it is getting air too easily when I open the throttle now. I'll purchase the replacement ASAP and give that a try. That should be my new baseline anyways. While I wait for the new filter, I'll check for mice nests in the filter area to rule that out. Thanks guys!!
    Purple and Sthrnromr like this.

  10. #19
    Senior Member Fred's Avatar
    Join Date
    Dec 2011
    Location
    Turtle Wrangling the Sierras
    Posts
    18,406
    Your new air filter should not require much oil to function correctly. Ignore any of the Yamaha videos that instruct you to pour almost a whole liter of their proprietary Yamaha filter oil on the filter, just a few tablespoons is plenty if worked into all the pores then blotted almost dry. One bottle or aerosol can should last years of dedicated maintenance in my experience.
    Last edited by Fred; 05-15-2019 at 10:25 AM.
    Sthrnromr and GaryL like this.
    2003 TW200 "Betty Boop"
    2006 TW200 "Nibbler", a.k.a. “Mr.Gizmo"
    Hidden Content All Things Considered I’ld Rather Be Motorcycling

  11. #20
    Senior Member kennethshaw's Avatar
    Join Date
    Jan 2011
    Posts
    170
    Well, no luck still. Other things I tried include:
    1. Installed new air filter after oiling. No change. Bike still would not start at 2-2.5 turns of the air mix screw.
    2. Turned the air mix screw to 3.5 and bike would start, idle weak, and die after 5 seconds. If I tried to add throttle quickly, it would die. If I rolled on the throttle very slowly, it would surge a bit, almost die, and be intermittent in this fashion. In the end, it would always die.
    3. Sprayed starter fluid near the carb boots to see if there was any type of air leak. No change.
    4. Choked the bike after getting it to idle at 3.5 turns out on the air mix screw and it would immediately die.

    What I suspect:
    1. Gut is telling me that it may be the CDI based on what I'm reading.
    2. Perhaps there is a passage in the carb that I just can't see that is clogged. All jets are clear so I know that isn't it.

    Options:
    1. Buy new CDI from member TomBauer
    2. Buy new Carb from Partzilla
    Both are expensive but looking more attractive by the moment. Any recommendations on which to go with first? Should I place the CDI in the freezer, then install to see if it helps?

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. Starting issues, do short rides kill it?
    By brokenfixed in forum Technical Help
    Replies: 27
    Last Post: 08-29-2016, 01:48 PM
  2. Starting issues on 2013
    By zakmontoya in forum Technical Help
    Replies: 6
    Last Post: 11-02-2015, 04:04 PM
  3. 93 TW Starting and Running Issues
    By Squatch Buster in forum General Discussion
    Replies: 13
    Last Post: 08-05-2015, 08:31 AM
  4. starting issues
    By cbelena4 in forum Technical Help
    Replies: 9
    Last Post: 10-28-2013, 09:29 PM
  5. 1992 TW200 $1150
    By Smokeslider in forum TW200 Classifieds
    Replies: 0
    Last Post: 02-21-2011, 03:11 PM