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Discussion Starter #1
Ok. I am really not trying to be a pest here. I have searched, read, searched and read so more, but it seems like information is somewhat scattered. (This is not intended to be a slight at all. I may just be missing a crucial step to take me where I want to be).*

*As mentioned in my intro, I belong to Case garden tractor forums. Those forums have pretty much ALL the parts and service manuals available on those forums. Not sure if Yamaha is like John Deere and they have copyrighted to manuals so you have to buy them or if they are here and I do not know how to get to them.

So I had did a lazy man carb clean. Noted a 114 and 40 jets. I take this to be stock.

---1996 TW200---7,600 miles. ~1,200 feet elevation

Went after the little mixture screw plug last night. There was a very tiny dot in the middle of it, but not large enough to accept a sheet rock screw. I drilled it out and removed screw. I have read that all of these carbs' mix screws should be at approx. 3/4 - 1 turn out. Mine was already at 2-1/2 turns out (I found this strange).

I bottomed it and killed engine around 1 turn out. I turned it out and was right at 5 turns before I got the blubbering. I returned it to 3 turns out.

A bit more power was noticed and the bike started to pull the front end up easier. However, it still falls on it's face when throttle is dropped off idle. This is not the reason for this post, as I do need to rebuild carb as I am sure that the o ring on seat is bad and allowing more fuel. That will be done before really piddling with tuning anymore.

While testing, I noticed a bit more valve noise. Am going to adjust tonight.

I realize I do this cold. At TDC (going to use cam mark). And from left side of bike, engine rotates counter clockwise.

Got this info from here...

Intake 0.05-0.09 mm (0.002-0.004 inch)

Exhaust 0.11-0.15mm (0.004-0.006 inch)

Ok, I got that. Did you guys buy the tool for the adjuster, or what are you using?

I also want to check timing chain adjustment. On my old TT, you did this whiling engine is running. I found no mention of that and/or where to have engine set at to check and adjust.

Thank you in advance, and again, I do apologize if these questions are redundant.

Jeff.
 

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You do not check it running on the TW. In Bdub's tutorial in the Technical Write Up's Section, Beginners Guide to Base Gasket Replacment (http://tw200forum.com/forum/technical-write-ups/2555-beginners-guide-base-gasket-replacement.html), there is a video on how to restore timing. Here it is, enjoy:

Here's a good video in the Picture's & Video's section/Instructional video's for adjusting the valves http://tw200forum.com/forum/maintenance-repair-instructional-videos/15312-video-tw200-valve-adjustment.html. A different, but effective way. Maybe it include's the tool(s) used. I haven't watched it for a while.

Besides the 10mm wrench, to hold the adjuster I've used, in no particular order, needle nose pliers, deck screw, and a tool a forum member made and sent me. At Yamie, they have the correct tool which shouldn't cost much either.

Good luck.
 

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Jeffrolives . Perhaps I misread , but , in your post are you advising your running a #114 main jet and a #40 pilot jet???......at 1200 ft above sea level?. If so , I'd say the main jet is way lean ( can't remember the OEM pilot jet off the top of my head) . Someone correct my error if I've made one in the aforementioned . TIA
 

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......................Noted a 114 and 40 jets. I take this to be stock..........................

---1996 TW200---7,600 miles. ~1,200 feet elevation

Jeff.

.........................your running a #114 main jet and a #40 pilot jet???......at 1200 ft above sea level?.
I have a #114 and have used it from sea level to 6000' and it has worked well. Maybe if I lived at 6000' I would want to re-tune it but for the brief time I was there it was fine.

You have a 20 year old bike. Get a new #114 jet no matter how good the old jet in there looks. The hole in the center corrodes / erodes resulting in a rich mixture.

True story: A friend replaced the old #114 with a new #116 jet and his TW ran better and he concluded the mixture needed to be richer. I said first try a new #114 -- your old #114 is worn out and is running richer than a new #116. Replacing with a new #116 is actually causing it to run leaner. Long story short, he bought numerous richer jets from ProCycle but also included a new #114. After trying the richer jets he tried the new #114 and his problems were solved. True story.

The picture is from my carburetor. I was having troubles getting rid of a WOT miss. After trying everything I could think of the only thing left was a new jet. After installing the new jet, as soon as I started it, I knew my troubles were over! On my second TW, the first time I cleaned the carburetor, I automatically replaced the jet. Eliminate the problem before it arises!

You can see the hole in the old #114 is bigger than the hole in the new #116 and a lot bigger than the hole in the new #114.

Jet2.JPG
 

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Discussion Starter #6
Thank you ALL who have responded to my inquiry. Very appreciate.

However, I not believe a difference problem has arisen.

Update-

Went home and found TDC with crank mark, soda straw in spark plug hole after feeling compression build with finger over hole, watching intake open and close, and when no resistance on either rocker arm (could wiggle both).

They were a bit loose. Set intake at .003" and exhaust at .005"

Closed them back up and checked the timing chain. The little indicator rod was nowhere to be seen. Unlocked jam nut and turned adjuster down until indicator was flush, then backed off to the .020" recessed. Here I found a problem. At this setting, there were no threads left on the adjusted to put the cap back on. I readjusted to allow enough threads to get cap on.

Started it up. Nice and quiet.

Went for ride. Seemed very stuffy. No longer wanted torque build and make front end light.

But while I was riding, my right Redwing boot felt warm. It has never felt like this before. Parked and put my hand on lower crankcase and if it would have been softer, it would have burned me.

Now, yesterday was the warmest it has been here since getting bike. 84* F. The bike never did sing (heat clicking after shutting down), but it sure felt hot.

Later on, I found TDC again and backed the adjusted back out a little more. Went on another ride and the power was back, wanting to pull front end up as the power built rolling into throttle.

I do not think I am too tight on the valves as being right in the middle would open the valve further and let exhaust out better, but maybe my thinking here is off.

I thought of backing that adjuster out a hair more. :mad: Did not make note of where it WAS set at, but I know I am nowhere near that now.

I have never seen another one of these around so there is nothing to compare it to. Do your bikes' crankcases get so hot that you cannot touch after shutting down? 84 is warm, but not really compared to what you guys are riding in.

Placing call to ProCycle right now.

Thanks again.

Jeff.
 
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