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650R valve help!

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Hey guys, bike has been running pretty well but I thought I would double check my valves as part of my winter storage but it's been years since i worked on a four stroke. I read online and confirmed my gauge to measure. I feel like I'm missing TDC or something as I saw a video saying the rocker should move freely. Mine is not moving at all. For TDC, is the T supposed to be in the middle of the site window? I tried to add a pic but it's not coming out well, there is a line with an F then a line with a T which I thought was TDC. Any tips on what I'm missing? My feeler gauge will not fit at the T, so I think I need to adjust it a little.20181129_092410.jpeg

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TDC is the T mark , but you are most likely at TDC on the exhaust stroke , instead of TDC on the compression stroke.  Turn the crank one full revolution back to TDC.

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35 minutes ago, notoriousE-R-I-C said:

Pull out spark plug and put a screwdriver in the hole...when it rises to its peak, there's TDC

 

I would recommend to not use a screwdriver to check for TDC.  There have been many instances where considerable damage has been caused doing this as the piston suddenly and forcefully rams the screwdriver upwards.  Also, do not use a pencil which can easily break inside the cylinder.  If you must put something in the cylinder a straw would be safer.   

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Well, I finally just pulled the stator cover and checked the valves, they appear to be in the middle of spec at .006 intake and .008 for exhaust and the gauge fit snugly under each. My plug looks a little rich to me after pulling it, any thoughts in my jetting while I have the tank off? Looks like I'm going to do my stator wind while I got the cover off and I have to wait for my new gasket to arrive. 20181129_102823.jpeg20181129_163945.jpeg20181129_163951.jpeg

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While notoriousE-R-I-C HAS super strong hands, most of us do not.   The cams and the cam chain can put extreme amounts of pressure on the crank and therefore the piston, especially on a big single.  Do NOT use a screwdriver or a barbed wire wrapped baseball bat to find TDC.  The F you see is the point that the spark plug fires.  The T is TDC.  You can be on TDC on the compression stroke or on the exhaust stroke.  With the valve cover off, put the T mark in the window.  If it is correct, both cam lobes will be pointed slightly away from the piston crown and at about a 120 degree angle from each other.  If not correct, at least one of the valves will be compressed.  You can watch the valve actuation as you turn the cylinder.  If one or both are still moving when you get to T, then you need to go around a full revolution to get to the correct TDC for checking the valves.  Pay attention to firsthere's advice.

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Another TDC question, everything says the rockers should move a little at the right spot, how much movement is that? Also, if I adjusted at the TDC-exhaust, can I just find TDC-compressikn and re-adjust before starting the bike?

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Hands have nothing to do with it!!! How amateur are you? You just put a screwdriver in a vertical hole and let gravity do it's thing WHEN YOU TURN THE CRANK BY HAND (like everybody) TO FIND TDC.

The screwdriver is sitting there with its own weight. And you could spin the crank with an extension and a socket spinning with just your fingertips...or maybe that's just me...man I love the internet! default_wink.gif&key=56b691046144ecb2770ec5a9cfb5efddcddfe1189ff6d027541fea22773efed4

Where's this aggressive movement that does anything to any metal doing valve work on any rocker arm bike...???

The aggression must be somewhere else if you're smashing pistons....

 

 

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Don't get too involved in "T" or "F" thing in the window. You've already got the valve cover off so, when the cam (either cam) lobe is 180 degrees from the rocker you are now on the base circle of the cam. Take your clearance measurements on that cam. Once done, rotate the flywheel so the other cam is now 180 from the rocker. Measure those clearances. Done.

As Firsthere mentioned, make sure the decompressor on one of the exhaust valves is out of play. If you're not familiar with this, monkey around with contraption hanging of the end of the exhaust cam with the counter-weights. It's got a pin that slightly opens the one valve to make it easier to start. Just make sure the pin isn't opening the valve while taking measurements.

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If you turn the crank approximately 45* PAST TDC , it's far enough that the auto-decomp is deactivated.

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2 hours ago, Gary Strombeck said:

Don't get too involved in "T" or "F" thing in the window. You've already got the valve cover off so, when the cam (either cam) lobe is 180 degrees from the rocker you are now on the base circle of the cam. Take your clearance measurements on that cam. Once done, rotate the flywheel so the other cam is now 180 from the rocker. Measure those clearances. Done.

As Firsthere mentioned, make sure the decompressor on one of the exhaust valves is out of play. If you're not familiar with this, monkey around with contraption hanging of the end of the exhaust cam with the counter-weights. It's got a pin that slightly opens the one valve to make it easier to start. Just make sure the pin isn't opening the valve while taking measurements.

Will this be when the rocker is at its highest point above the valve springs? I turned it over a few times and the amount of play I got in the rockers was nothing like the video I saw on youtube. In the video, the guys rocker could move like 1/4 inch up and down, mine was moving but not visible, just what I could feel by hand. With the valve cover on, I can't really see the cams that well and I'm hoping to leave that cover on to avoid taking more stuff apart at this point. 

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20 hours ago, notoriousE-R-I-C said:

Hands have nothing to do with it!!! How amateur are you? You just put a screwdriver in a vertical hole and let gravity do it's thing WHEN YOU TURN THE CRANK BY HAND (like everybody) TO FIND TDC.

The screwdriver is sitting there with its own weight. And you could spin the crank with an extension and a socket spinning with just your fingertips...or maybe that's just me...man I love the internet! default_wink.gif&key=56b691046144ecb2770ec5a9cfb5efddcddfe1189ff6d027541fea22773efed4

Where's this aggressive movement that does anything to any metal doing valve work on any rocker arm bike...???

The aggression must be somewhere else if you're smashing pistons....

 

 

How amateur am I?  This is my 55th year of riding.  37 of those were roadracing, everything from singles to GSXRs.  2 years of motocross until the Marine Corps told me I had to stop.  I currently own, ride and maintain 2 XR100s, Aprila Mile R, Honda Superhawk, Burgman 650, SV650, DRZ400SM, DRZ400S (for Sale) and an FZ10.  I've owned well over 50 motorcycles, including a Zundapp 250, Cushman Eagle, Maico 250, Allstate 125 and a Montgomery Wards Riverside.  I've always done my own maintenance.  I was lead technician in a motorcycle shop for 7 years with 4 mechanics working for me.  I don't have a big single to test without pulling a lot of body work, but I just checked an XR100 and with the spark plug out, it took 8 pounds/feet to turn the crank 2 full rotations.   I can turn it by using the flywheel, but I can't control the rotation through 2 full rotations.  If I had seen one of my technicians using your method, he would have been fired immediately.

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timbanditos, look at the thickness of the feeler gauge.  That is how much play you should have when you wiggle the rocker.  You should not have to adjust the screw more than 1/4 turn.  

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You do valves with the motor running...got it

 

8ft lbs...you need new main bearings.

 

I just did a street bike clutch where the springs were 9ft lbs. I put all 5 bolts in with a 10mm socket on a watcher screwdriver. When I put the torque wrench to them, they all clicked at 9 and needed no extra tightening...must be my strong internet porno fingers if 8 ft lbs is a huge amount to you

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