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Discussion Starter #1
I did a stupid thing with my 96 TW200. I use it everyday so when I had a hard time seeing through the view-glass I added a bit. Of oil.



Like a good monkey I did it more than once. Well it started acting starved at the top of each gear.



I pulled the air filter- full of oil



I drained the oil and added the right amount (1.25 liter) and replaced filter-cleaned out box.



Drove it about a mile and it made a deep hollow sound and lost power and died.



I am thinking of some blown gasket or seal or seat or something even more disastrously expensive.



I got a exploded diagram and disassembled carb and scrubbed with solvent. still no start.



I am handy and have maintained it, changed sprockets for more speed/less revs and can work on it.



Get the name calling over, I am all of those things and more but can anyone help me save a noble steed?



I really really like her.
 

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Just a shot in the dark, but have you re-checked your air filter?



There's a drain in the bottom of the airbox housing. It looks like a short piece of clear tubing flattened at the end. It's possible that there is still oil sloshing around in there.
 

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On Cali models it is also (remotely) possible that oil got into the canister or lines, causing the fuel tank to cavitate.
 

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Discussion Starter #4
On Cali models it is also (remotely) possible that oil got into the canister or lines, causing the fuel tank to cavitate.


Thanks very much. What a great paint scheem on your bike! At first I thought it was an old Norton. Are there some sort of compression seals or gaskets that can be blown out by too much oil/pressure. It sure felt like a failure of some pressure barrier? The mechanics seem straight forward and I have detailed manuals. What would you "peek" into first, the crank-case or the head?
 

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A "hollow" noise is kinda subjective. But in general one of two things tend to happen in an overfill situation. Neither would involve blown seals. One is usually benign, the other is catastrphic.



Within reason the crankcase vent protects your motor by dumping the excess pressure into the airbox. If you sufficiently overfilled it to the point of overcoming this ststem it would generally just stall from the pressure under the piston. Other bad stuff COULD happen, but generally not.



The second possibility would usually result from parking the bike with the airbox full of oil. The oil would then leak past the carb through one or both of the valves, filling the cylinder with oil. The next time you tried to start it the cylinder would lock up hydraulically, possibly breaking a piston, or bending a rod.



The same thing can happen if your carb float sticks open. Fuel will leak past the valves, filling the cylinder with liquid. Except that in the case of liquid gasoline it will leak past the rings into the crankcase at a much faster rate than oil. Left overnight it could fill not only the cylinder, but the crankcase and aibox as well. In this case your motor "gets it from both ends". No bueno. This sometimes goes undetected at first, simply looking like you absent mindedly overfilled.



Since your bike ran after you solved the overfill, I'm guessing that neither situation occurred, and that you just have some goofy fuel issue. Unless your "hollow" sound was a piston hitting a valve.
 

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thanks again,



I will do my homework and have details in hand when I return. I apprechiate the help.


I gotta edit the statement regarding the seals. They COULD blow, but on a TW none of them would directly affect operation. You'd just have leaks around things like the kickstarter, shifter, etc.
 

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Hollow sound then loss of power... ouch.



Pull the spark plug out, turn the engine over & check for compression.



You didn't say anything about changing the oil filter with the oil...

did you change it? And did you check for the correct one, with the four holes?

 

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Discussion Starter #10
Thank you for the reply! I will check both of those things. I did put a finger over the plug seat and crank it and it tried to blow my finger off of the hole. I will check the filter though.



Thanks again,



Jim
 

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Next idea... when the bike runs out of gas it sounds "hollow" and loses power... so... fuel flow... do you have good flow from the tank? Could something be partially blocking the fuel line?
 

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Discussion Starter #12
Actually several things happened with the fuel and I was so caught up in the oil overfill that I thought things were just a chain reaction. I better get all the details out there and quit making assumptions.



After I corrected the oil overflll was when I noticed that I was getting less power at the top of each gear and it died occasionally when cold. I upped the idle some with the idle screw and ran it for a bit. I came back the next morning and there was a small pool of gas in the absorbant material I had down for oil, It had come from the overflow at the bottom of the carberator.



I checked my gas after work and discovered that i was almost empty way-earlier than I should have been. I wrote it off and just thought that more had dripped than I thought. Now I wonder:



What if some sort of siphon began when I uped the idle and it backed up to the point that it crossed over into the intake and filled the case with gas? That sounds far fetched but I need to check it out.



Thanks again!
 

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This'll sound stupid, but check the spark plug. I replaced mine this spring and the bike seemed sluggish. After a couple of days I checked the plug and it was literally loose. Once it was tightened, the bike ran a lot better....
 

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Actually several things happened with the fuel and I was so caught up in the oil overfill that I thought things were just a chain reaction. I better get all the details out there and quit making assumptions.



After I corrected the oil overflll was when I noticed that I was getting less power at the top of each gear and it died occasionally when cold. I upped the idle some with the idle screw and ran it for a bit. I came back the next morning and there was a small pool of gas in the absorbant material I had down for oil, It had come from the overflow at the bottom of the carberator.



I checked my gas after work and discovered that i was almost empty way-earlier than I should have been. I wrote it off and just thought that more had dripped than I thought. Now I wonder:



What if some sort of siphon began when I uped the idle and it backed up to the point that it crossed over into the intake and filled the case with gas? That sounds far fetched but I need to check it out.



Thanks again!


This was your original problem. Fix it.



You were "having trouble seeing through the sightglass" because your oil was full of gas.



Your float is stuck or your needle is worn out, and your stalling and loss of power is probably due to that as well. As I said above, this usually goes unnoticed and gets mistaken for overfilling.
 

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Discussion Starter #15
Thank everyone for so much of your time. I just went back and read and reviewed everything. You are right. You really used Shirlok Holmes' approach of eliminating the imposable and whatever is left, no matter how improbable is the truth. That must be it. I have been inspired by what you guys have done with your bikes that I would love to preserve and improve mine.



You have given me much to investigate and I will proceed. Thank you and please tolerate my play-by-play as I zero in on the fix.



Jim
 

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Discussion Starter #16
OK I think I know what happened. First though I will tell you what I know. The real valve when I pulled the top of the head was securely seated in its seat.



The valve to the front however was wedged against the iron to the front way above its seat. It seems like a classic thrown rod but I have learned much here and will reserve judgment.



The image I am trying to embed here will show the rear seal seated perfectly.



My link



The forward valve though is as above,. If I grab the top sprocket of the timing chain it should operate the valves right? This one is frozen for about 45 degrees.



Left to my own I will buy a new valve assembly, gaskets, etc. and reassemble. Any other ideas?
 

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Discussion Starter #17
I pulled everything and sure enough. The exhaust valve was bad and fractured. I want to replace it but I cannot figure out how to pull the cam-shaft. I have the sprocket off but do not know how to get the collar off.
 

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Have you downloaded the shop manual, which has step-by-step instructions on how to remove the cam?
 
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