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Hey fellow TDubbers,

Been trolling this forum for months now and received tons of awesome info especially in the technical write ups section! Thank you to all of you that have spent tons of time sharing your knowledge with me and everyone else!

Ran into a problem with my new (to me) 2007 TW200. Was cruising down the road in southern Alabama at about 40 mph, when the ol girl just died like she was empty on fuel. Here's a bit of the trouble shooting I have done so far to give some background and help narrow conclusions:

-Fuel Tank was and is full
-All switches on and peacock open (tried both on and reserve)
-Cleaned carb and jets and ensured fuel was getting through and float working the way it should
-Battery completely charged
-Spark Plug replaced and check that spark was good
-Sprayed starter fluid directly into carb and then into spark plug hole, still nothing
-The guy I bought it from just had $500 in work done to it to include all the normal service stuff, just cause he wanted to sell it in tip top shape

Long story longer:
Bike has power and cranks and cranks but wouldn't start. Finally took it to the local shop to diagnose the problem. The guy checked it out and said there's no compression and for some reason the timing chain is incredibly tight!

Brought it home, tore the head off and this is what I found. Valve is stuck open a good 1/8 to 1/4 inch. What could the cause be? Is it just the valve that need replaced or should I dig in to the piston also? Timing seemed to be way off before I took it apart too. Any underlying issues that you all may have experienced or could think of that I should check also?

What is the best way to fix this and where's the best place to go for parts? Thank you in advance for taking the time and helping me out!
 

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No, I backed it out all the way and even tapped on the valve to try and get it to move a bit but it is either bent, or stuck really well. Didn't want to pound on it too hard until hearing some feedback.
 

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Welcome to the forum!! :D

Not sure, but it looks bent to me. No damage to the cylinder?

No, I backed it out all the way and even tapped on the valve to try and get it to move a bit but it is either bent, or stuck really well. Didn't want to pound on it too hard until hearing some feedback.
 

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Sounds like you just need to rebuild the head then, then go through the timing, adjustments carefully. We have Shop Manuals in the Technical section that might help you. We'll help you through this if you need it, so keep us posted.
Cylinder seems to be in great shape and no sign of metal or ring pieces. Just a good amount of carbon build up. I think I have a pic...
 

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No, I backed it out all the way and even tapped on the valve to try and get it to move a bit but it is either bent, or stuck really well. Didn't want to pound on it too hard until hearing some feedback.
If there is no touching between the valve adjuster on the rocker arm and the valve tip and the valve still won't close, the only possibility is that the valve stem is bent, leaving out the very remote idea that there is something stuck between the valve head and the seat...which would be obvious when you pull the valve. It doesn't take much of a bend to freeze the valve.

Your piston is probably fine, fix the valve and then test for compression.
 

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I hope that is the case! I'll see what I can do about tracking down parts and doing research on how to change these little suckers... I'll keep ya posted. Thanks!
 

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Sounds, and looks like you have broken intake valve. This is what I found on Bananachunks' Little Monster (see thread below starting at post # 23).

http://tw200forum.com/forum/tw200-classifieds/41858-norcal-nutjobs-its-time-little-monster-needs-good-home-asap.html

See if you are able to carefully pull the valve out and see if the valve guide is damaged, i.e., cracked. If it is not damaged, you can probably get by with just replacing the valve. If the guide is damaged, you may want to consider replacing the head as I did.





 

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Discussion Starter #12
Check your oil filter for the 4 holes. The lack of lubrication has ruined many a head.
That makes a lot of sense! I will check that out when I have some daylight. Odd to me that this bike was just serviced and tuned just to have it be this far out on the timing and also a possible lubrication issue because of the wrong oil filter... Makes me wonder if they actually tuned it or just ran a rag along the side to give the appearance of work and charged the poor fella a bunch of $?...
 

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I among others have had the same bent valve/broken guide failure.
In my case a piece of guide broke off and violated the poor innocent cylinder and piston.
Fortunately Elime fixed me up with a Wiseco piston and a matching honed cylinder.

So what causes the failure? Like the chicken and the egg, which came first?
Does the valve stick, then get hammered by the piston bending the valve stem until the valve guide fractures?
Or does the valve guide crack first thus binding the valve so that valve spring doesn’t retract valve out of way of approaching piston in time?
 

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Hey Fred, does that cylinder from Tony have a broken cooling fin near its base?
I can answer that -- YES! That cylinder was a freebie from TW-Brian that I passed on to Fred.

As for the broken valve in question, something doesn't look right with the valve keepers -- see red arrows. Maybe it is just the lighting......

valve keepers..jpg
 

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I can answer that -- YES! That cylinder was a freebie from TW-Brian that I passed on to Fred.

As for the broken valve in question, something doesn't look right with the valve keepers -- see red arrows. Maybe it is just the lighting......

View attachment 117330
Take a look at these . . . . .

Broken Valve 1.jpg

Broken Valve 2.jpg
 

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I hadn't noticed it before but in post #11 I see the tip of the valve broke off and that is what I assume to be is the piece of metal between the two keepers. That is some serious forces going on there. I would look closely at the aluminum casting that holds the rod the rocker arm rotates on. Probably better off just using another head.
 

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Yes, the same jug Tony got from you, right?
That's right. Didn't I also send you a head?

I hadn't noticed it before but in post #11 I see the tip of the valve broke off and that is what I assume to be is the piece of metal between the two keepers. That is some serious forces going on there. I would look closely at the aluminum casting that holds the rod the rocker arm rotates on. Probably better off just using another head.
That's exactly what I did. I got a head from Dr Terrible that I think was fished out of a lake somewhere in Canada :eek:.
 
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