Have you cleaned the carb?
Seeing its my first post i would like to say hi to everyone I'm working on my first 4 stroke in a long time,its a 89 Tw200 with the turqois tank,The bike starts easy and idles very smooth but when i touch the throttle it wants to die and if i roll the throttle it will rev and backfire throught the exhaust, Then i discovered after going through the carb,pulling the flywheel off checking for a sheared keyway and valve clearance it will run after its good and warm and even had it out for a 10 minute ride,but after it sits for awhile and cools down the same thing over again. I checked all threads on here and only found one guy mention this but no replies to it, It may be the ignition coil ? what iam going to do in the AM is take my heat gun and start heating up the key electrical components and see what gives,If anyone else has any ides let me know. Thanks Don
Hi, Yes i found a chunk of rubber debri just under the screen on the needle and seat and cleaned it again for a second time to make sure. its odd that it will run normal after the engine warms up but takes 10-15minutes, i want to find out whats the problem before it fails for good. I will try heat the coil with my heat gun today and update what happens then,i have spare coils also so i may swap it out, i hope its not the CDI
I also noticed the fuel pet cock will not stop flowing fuel in the off position and the exhaust is missing the end cap and some of the baffle,the guy said it blew out on him when this all started.
have you tried adjusting your pilot screw it may be running to lean. just something to check. what does your plug look like.
not a TW owner but i play one on this forum.
Ive got the pilot turned 3.5 turns out,my OEM manual doesn't say what to set it at on the slide carbs so,Maybe i will try another turn and see what it does, The plug is nice and dry and light brown when running good but black if i pull it before it warms up.
After 10-15 minutes it takes to warm up i work the throttle to get it to run proper and it works itself out so thats why i wonder if its a fuel issue or electrical. I will be going out to the garage in a couple hours and see what happens. Ty
Okay, So i just came in and sure enough i heated the coil with the heat gun and no difference,then i tried the CDI box located on the right side cover beside the tool kit just on the otherside of the exhaust pipe and the bike ran good almost instantly, I will try one more time tonight or in the morning to make sure before i order one simply becuase i had it running breifly while doing the ignition coil. So i will update this tommorow, If anyone has any of the parts mentioned pls message me, he wants to replace the exhaust also but seen something on ebay. Don
Does your carb have a round black lever on the left hand side of it? [starter plunger] When i first got my tdub i had similar issues of it starting but not running well until warmed up.i discovered how to fine tune the starter plunger choke knob thingy by pulling it out to start then let it idle high until idle dropped then slowly push in knob until it idles and revs without cutting out. you can usually ride the bike like this for the first few minutes until it warms up then push the starter plunger all the way in and the bike should rev ok without bogging. just the cold nature of some of these older carbs. There may be some tweaks that can smooth this issue out by carb cleaning rejetting etc , but i have learned to live with my cold natured tw by using the starter plunger.
you may want to find out where that chunk of rubber came from.
not a TW owner but i play one on this forum.
I pulled the pet cock apart today and instaled a inline filter,i found out the peice of rubber came from the rubber gasket inside the pet cock, not the "O" ring but the flat rubber peice that fits between the selector and housing, So that solves where it came from, it seems to be running better off the "get go" without warming now so what i will do is order a new pet cock rebuild kit becuase the seal is no good and in the OFF position the fuel still leaks,For now i flipped it over and it stopped leaking,
I noticed air in my line with the filter on and it wouldn't run so i pulled the line and got the air out and now it runs again, Anyways this could have fixed the problem and will update once i try it again tommorow cold and order a new rebuild kit meanwhile. Thanks guys for the help and hopefully we dont need a CDI becuase by the sounds of things these CDI's just quit usually so i could be dealing with a fuel issue all along.
You are correct. The soft parts of a petcock are simple to install and while relatively inexpensive, you can buy an entire petcock for around $15. I'd fix that whatever you think the warmup problem is. It should not take 10 or more minutes to warmup this bike. I typically leave the choke on for 15 or 30 seconds in the summer and probably less than 90 seconds pass in the winter before the bike tends to bog a bit from being warm enough to run on a leaner mixture. I'd suspect carb/fuel problems, but then again I'm not there. Good luck. Tom
Tom - TW200 2002, Kawasaki VN 500 2006
Central New Mexico