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New member here, relatively new to using forums and brand new owner of a TW200. I know enough about forms to know that older members sometimes don't like rehashing issues that have already been discussed, that said I will gladly read anything already posted if someone could point me in the right direction.

I recently purchased my 1987 TW from a dealership in the North Dallas area. Buyer beware I should have followed. I wanted one of these bikes for some time and let that cloud my judgement. Any way its mine now.

It starts fairly well and idles good enough after reasonable amount of warm up time. Once I try to roll on the throttle whether sitting in neutral or trying to drive off it sputters and spits and will not accelerate hardly at all. After it runs long enough to be good and warm it begins to falter quite a bit at idle. I'm not sure if its carb issues or timing advance issues or both? Anyone have any suggestions as to where to start?

Also where can I purchase a service manual? Are there any members in the north Texas area that know where I can get this bike worked on?
Seems very few shops will work on bikes older than 10 years...

Thanx in advance for any suggestions.
 

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Welcome to the forum Poppa!

Don't worry about your purchase, we should be able help you figure out your problem and get it fixed. The 1987 was the first TW model year and some on this forum feel that it is the fastest year. This year also has a unique electrical system and a CDI that is considered to be failure prone. From the information that have provided it could carb or fuel related, or CDI related. You should try to rule out any carb or fuel related problems before assuming that the CDI is the problem.

Service manuals can be found for downloading on this forum along with millions of threads on carbs.

Have patience, work with us and we'll get you up and going as quickly as we can.

Brian
 

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Discussion Starter #4
Thanx to everyone for the encouragement so far.
I'm leaning towards carb issues as well. I also have a little Honda 100 trail bike and have had the carb off it and tore down to clean so I'm kind of familiar with carb work but really only just enough to get by.
The dealership said they had thru the bike pretty thurough. ? It has new spark plug but when I pulled it too check it, it was pretty sooted with black carbon. Pretty sure that's a sign of running too rich. Just not sure how to attempt to lean it out.
The odometer shows 3632 miles. The dealership may have replaced the coil or the CDI because the mechanic was saying something about it being unique to that year model bike. Something about it being a DC instead of an AC version?
 

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Welcome to the forum!

It kind of sounds like your choke knob is pulled out, have you double checked that? That would explain all your symptoms, including the sooty plug.

The CDI is specific to the '87. Many of them are still running great after all these years, but many of them have also failed. Fortunately, new '87 CDIs are still available (although expensive).

Good luck!
 

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Welcome! I too have an 87 with roughly the same amount of miles. It has mostly sat since I got it. Just got it started again last night and I am right where you are so we are suffering through this carb part together. There is a ton of useful info on here and a lot of folks willing to help. You will get it figured out. If I recall I saw a thread on here a while back when I first was trying to work on mine that was all about the carb and carb cleaning, etc. If I find it again before you I will point you to it.
 

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Discussion Starter #9
Thanx Imposter71. Its got me a little baffled as to where to start. The spark plug indicates its running rich, lots of black soot on it. Throtle response acts as though it's starving for fuel or lean at higher RPM. Today will be my first opportunity to dig into it and see what I find.
 

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I love my '87 TW. And as TWBrian said earlier in this thread, some people think the '87 is the fastest. This is mostly said in fun, but there does seem to be truth to this thought. Mine is faster than my '99, and handles better.
 

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Discussion Starter #11
yep, no closer to figuring it out. Pulled the carburetor, pulled the bowl. It looks as though it has been cleaned recently. the main jet is stamped "AB 115". I have no idea what the factory jet is supposed to be. I read so much info on this blog yesterday that it gave me a head ache and I can't recall where i saw some info about those kinds of specs.
any way the symptoms seem to contradict them self. I pulled the spark plug and it is covered in black soot, usually a sign of running too rich, right? the bike starts and idles well but stumbles, cuts out, runs crappy once i try and rev the engine medium to high rpm. Doesn't that usually mean its starving for fuel or running lean? I am also noticing a nasty sound in the jug from time to time, sounds like someone on the inside with a hammer banging on the wall of the jug. Is that pre-ignition or bad bearing between the piston and piston arm?

Manuals? I have seen the links on here but they seem to point to on line subscription only manuals. Anyone know where i can buy an actual hold in your hand service manual?
 

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Forum member PlacerLode has manuals for sale, here's the link:

http://tw200forum.com/forum/tw200-classifieds/37201-new-ricochet-skid-plates-factory-yamaha-tw200-soft-cover-service-manuals.html

PM him. He's a great guy to deal with, his name is Fred.

About your intermittent running problem... Do you have a old inductive timing light anywhere? Hook it up to the batt, clip on the pick up to the spark plug wire, hold down the trigger and run the bike. If it flashes steady with no problems, the CDI should be ok, and this would suggest the carb is at fault. If it runs good at first, then starts cutting out and the flashing becomes irregular, it may be the CDI.

I think it is somewhat carb related (dirty pilot or worn out jets or incorrect jets or adjustment of the float level in the bowl) but you may also have a CDI prob.
 

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Poppa,

I'm right there with you. My 87 is now starting and idling but dies when I give it gas. If I recall you said you recently purchased your from a shop, did it run well initially when you got it or did you purchase as is?
 

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Dirty or worn pilot jet most likely
Poppa,

I'm right there with you. My 87 is now starting and idling but dies when I give it gas. If I recall you said you recently purchased your from a shop, did it run well initially when you got it or did you purchase as is?
 

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Discussion Starter #15
Poppa,

I'm right there with you. My 87 is now starting and idling but dies when I give it gas. If I recall you said you recently purchased your from a shop, did it run well initially when you got it or did you purchase as is?
I purchased it as is. They claimed it ran well but had I ridden it before I purchased it I wouldn't have. It starts and idles but thats about it.
 

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Forum member PlacerLode has manuals for sale, here's the link:

http://tw200forum.com/forum/tw200-classifieds/37201-new-ricochet-skid-plates-factory-yamaha-tw200-soft-cover-service-manuals.html

PM him. He's a great guy to deal with, his name is Fred.

About your intermittent running problem... Do you have a old inductive timing light anywhere? Hook it up to the batt, clip on the pick up to the spark plug wire, hold down the trigger and run the bike. If it flashes steady with no problems, the CDI should be ok, and this would suggest the carb is at fault. If it runs good at first, then starts cutting out and the flashing becomes irregular, it may be the CDI.

I think it is somewhat carb related (dirty pilot or worn out jets or incorrect jets or adjustment of the float level in the bowl) but you may also have a CDI prob.
Thanx LittleTommy,
I do not have the test equipment you mentioned but could probably find one. So much about this bike is sketchy its hard to know where to start. I did as you mentioned and PM Fred about a manual. As for the carb I have torn it down and cleaned it twice now. A few things stand out. The pin that holds the float assembly in between the two mounting post is slightly bent. I do not know if that was something the previous person did or if that's factory. Either way it seems to be causing the floats to stick open and fuel now runs out of the overflow. (it did not do this before I took the carb apart and reassembled though) I did check the float level based on what I have managed to find online and it seems to be with in tolerance 26mm-28mm. The main jet needle may not be the original as it has one that allows for lean/rich adjustments by "E" clip. Reading and researching it looked like that had to be done with washers on this model bike. Also the main jet is a 115 and everything I have seen so far suggests it was a 114 from the factory. Since the bike seemed as though I was leaning out as you roll on the throttle I adjusted the needle to the mid setting as it was set to the most lean setting when I pulled the carb apart to clean it. No help from that change...
The dealership I purchased it from said that they had done something with the CDI but I do not recall what. I just remember that they mentioned it was the only year bike with the type of CDI it has on it. That kind of leads me to wonder if that is where my problem lies?

I am bumping up against the limits of my mechanical knowledge at this point. I guess the good news is if I get it figured out I will have learned something new. Somehow that sentiment isn't soothing the frustration just yet. LOL
 

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you have to take out both jets(pilot jet and main jet) and soak them with carb cleaner and blow them out and visually look through them to make sure they are clean. I recently did 3 bikes and the low speed or pilot jet gets plugged first because its the smallest. you dont have to disassemble the entire carb,just unscrew both jets and clean them and spray carb cleaner in the holes also and blow them out.
 

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Discussion Starter #18
you have to take out both jets(pilot jet and main jet) and soak them with carb cleaner and blow them out and visually look through them to make sure they are clean. I recently did 3 bikes and the low speed or pilot jet gets plugged first because its the smallest. you dont have to disassemble the entire carb,just unscrew both jets and clean them and spray carb cleaner in the holes also and blow them out.
I have had that carb completely torn down as far as it will go then left all of it in a vat of Carb cleaner for a few hours. Verified every opening or orifice was clear either by tiny brass wire or air hose. I'm starting to think the carb is not the issue. I don't think the CDI is advancing the timing as the RPM's go up. I don't really have any diagnostic tools to check that though. I'm also not 100% the generator/alternator is up to par either. When running at idle the head light dims WAY down. I know these old bikes did that some but this seems excessive and does not seem capable of keeping the battery charged and that's with a brand new battery.
I did find a motorcycle mechanic in my area that says he can fix it thought so I may have to give in and let the professional handle it. :(
 

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Well, this probably won't help your issue but since it is older and you can't really trust that the shop went through it... Here is what I have found/done with mine so far.

Completely emptied, rinsed, and let the tank dry out. It is still not like new inside but I feel pretty good that that at least most of the debris that could have been in it is gone.

Replaced the fuel petcock. It worked but not great. When I removed it I found both screens/filters missing and where the reserve one was supposed to be was completely filled with junk.

New fuel lines. ( Also got a little pancake inline filter but have not put it in yet - (may just wait and get a 90 degree one but I feel good about the fuel being pretty clean because of the above steps)

Fresh non-ethanol fuel.

Haha, of course all that being done mine is right where you are but I at least feel like I took out some variables. I am going to clean my carb (again) next. I went through it quick and that is what got me running but I am not a mechanic and really should have done a more thorough job. My air screw is 3.5 turns out. Was 2.5 and I turned to see if there was any change but there was not. I am going to put it back to the 2.5 as suggested on here as a starting point until I get the carb cleaned again and see what happens. Good Luck and keep us posted on your progress.
 
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