Global Moderator Pursuvant Posted June 12, 2022 Global Moderator Share Posted June 12, 2022 Part 1 << Part 3 >> 'continued from Part 1 Essential Knowledge These 3 simple sketches are views from the "RIGHT" side of bike (foot brake side). All 3 sketches show the cam gear's timing marks in red for emphasis - they are only stamped lines on the actual cams. First sketch, is what is going on inside the cylinder head as shown in Part 1. Third sketch shows a correct installation of the cams in the cylinder head. But without x-ray vision, the only thing you can see directly while removing and installing the cams, is the sketch in the middle. The intake cam has a single timing mark of interest with a large letter "I" stamped next to the timing mark. The exhaust cam has two timing marks. That's essentially it, simple to understand. So don't let the cam become complex when you see this (below) Just look at that picture and say "it's just a cam sprocket with two timing marks to align with the engine case". Because that is all it is. Removing Cams Refer to the third row in the Crank Chart "Crank Rotation Degrees 360" - this is the position for cam removal and installation (cylinder #1 TDC Exhaust Stroke). Rotate the crankshaft counter-clockwise until the Rotor Timing Marks are "ALIGNED" (RED timing mark added for clarity). Check for the cylinder #1 Cam Lobes Facing "FACE EACH OTHER". If they are not facing each other, continue with another rotation counter-clockwise of the crankshaft, until the Rotor Timing Marks are "ALIGNED". And repeat the check for cylinder #1 Cam Lobes Facing "FACE EACH OTHER". This (below) is the view from the "RIGHT" side of bike (foot brake side). Check the cam gear sprockets, they should be aligned with the top of the engine cylinder head. The intake cam with the single timing mark and the stamped letter "I", aligned with the cylinder head. The exhaust cam has two marks, and they are highlighted in red for emphasis. Using a straight edge placed along the top of the cylinder head, makes it easier to see that the two timing marks on the exhaust cam are aligned with the cylinder head. Stop and look at the two cams while they are in time, before removing them. Take some pictures, from both sides of the bike, so you have a photo record of the cam gear timing and the orientation of the cylinder #1 cam lobes just prior to removal. And take some pictures of the cam chain tensioner too. At reassembly, they will be put back and will look exactly like they do now before removal. DO NOT ROTATE THE CRANKSHAFT ONCE IT HAS BEEN ALIGNED FOR CAM REMOVAL. IT MUST REMAIN IN THE SAME POSITION UNTIL THE CAMS HAVE BEEN REINSTALLED AT THE END OF MAINTENANCE. EDIT 2023.02 Count Timing Chain Pin Links Between Timing Marks This (below) is the view from the "RIGHT" side of bike (foot brake side). Confirm the "offset" between the exhaust timing mark to the intake timing mark in timing chain link rivets (I call the rivets "pins"). On the exhaust cam chain, start counting from PIN #1. Count 31 pins. You should end up with the intake timing mark aligned between cam chain pin 31 and 32. If your cams have a different pin count, it is a different engine model than used in this "how to". You can still use the tutorial, but make note of your engine cam timing "pin count", and use that count to check for correctness when you reinstall the cams. This count of links between timing marks will be a key indicator during the reinstall of cams, that they have been timed properly. Continue with the CCT removal. The spring assisted hydraulic Cam Chain Tensioner (CCT) needs to be retracted and removed. EDIT 2023.02 TIP - The CCT has a top and a bottom. On my bike it has been marked at the factory with a large ink/paint dot - that is the "top" of the tensioner when positioned correctly. Make sure you notice this TOP mark, and later reinstall it oriented correctly. CCT removal requires a "special" tool, a hex wrench that has the legs shortened so it can fit in the tensioner to retract it, and remain inserted the entire time the CCT is out of the bike. Removing the special tool will cause the CCT to "snap out" to fully extended. The tool is 3mm hex wrench, cut down so the short leg is 23mm, the tool leg is 44mm. Short leg can be a bit longer, just has to clear everything as you rewind. Here is the link for making the tool. Removing the CCT, start by removing the access bolt in the center of the CCT. Insert the special tool and wind the tool counter-clockwise until it stops, this will retract the tensioner that is pressing against the cam chain guide. Remove the two outer mounting bolts, and remove the tensioner - leave the special tool inserted into the CCT and set it aside. Below, the oil supply port is visible in the CCT opening in the cylinder. If you have ever wondered if a manual cam chain tensioner can replace the OEM - here is the APE manual tensioner on left and the spring assisted hydraulic OEM CCT on the right. The APE tensioner "body" is too small, the bike will lose oil pressure if the OEM is replaced with APE (APE pn#YTFZ09-PRO). I'll be asking for my $$ back - they said it will fit (physically it does, but the APE body is .933" and the OEM body is 1.003"). Using a new OEM gasket on the CCT is probably a good idea on reinstall. LET's ROCK PLUG ALL OIL PASSAGES/OPENINGS IN CYLINDER HEAD, SPARK PLUG OPENINGS, AND CAM CHAIN OPENING (when not rotating engine crank) WITH RAGS/SOMETHING BECAUSE ANYTHING CAN ACCIDENTALLY DROP INTO THE MOTOR. IN THIS EXAMPLE RAGS ARE REMOVED TO TAKE CLEAR PICTURES. IF YOU DROP SOMETHING INTO THE MOTOR, IT WILL BE A VERY BAD YEAR. DO NOT RISK DROPPING A VALVE SHIM OR ANYTHING ELSE INTO THE MOTOR. Remove the intake camshaft cap bar. Loosen cap bar bolts in small increments working from the outside to inside in a criss-cross pattern, and remove the cam. Not necessary to maintain tension on the cam chain, but some like to go that route. The engine timing is going to get set on reinstall, and that includes positioning the cam chain on the crankshaft sprocket if it has slipped off. Definitely find something to prevent the cam chain from falling into the motor, but if it does, there is a bolt that prevents the chain from going on a deep dive into the motor. Continue by removing the exhaust cam cap bar. Loosen cap bar bolts in small increments working from the outside to inside in a criss-cross pattern. Remove the exhaust cam, and secure the cam chain so it will not fall into the motor. Below a dowel rod runs thru the cam chain keeping it nicely out of the way. Below is the two exhaust valves for cylinder #1. The left valve has already had the bucket pulled and the valve shim left behind in the valve retainer "cup" is visible. The right valve has not yet had the bucket removed. For removing and installing buckets & shims, the best choice is to have a magnetic pickup tool and a non-magnetic valve lapping tool. I use both a MotionPro magnetic pickup tool and also a cheap valve lapping tool with a rubber suction cup. Motion pro tool Part No. 08-0652 EDIT: There is a more powerful magnetic pickup tool for pulling the buckets & shim together (1 x Mfg Part# CMMT98348 Craftsman magnetic pickup). You still need the MotionPro magnetic pickup for inserting shims in the valve retainer "cup", or pulling mis-shaped shims that get "stuck" in the retainer. The valve lapping tool with the rubber suction cup is always the best choice for reinserting the buckets, and can also be used to remove buckets if you don't want/have a magnetic pickup. Lapping tool stuck to a bucket. And if you are an old tymer from the olden tymes, you go with the old habits. I have a 30 year old stick with a rubber suction cup on it in my tool box, because yes. STOP BEFORE GOING ANY FURTHER PLUG ALL OPENINGS IN THE CYLINDER HEAD THAT PARTS COULD FALL INTO. Only pull the buckets that measured out of spec, that need a new shim thickness to get back into spec. Before pulling any shims, make an organized place to put each bucket and shim, so it's clear what cylinder and valve they came from. It can be as simple as using a zip lock baggie, and put 1 bucket with it's shim in each bag along with a note identifying which cylinder and which valve it came from. The buckets go back in with the same valve they came out of, and the old shims will be used to calculate the thickness of new replacement shims. You can't do any of that, if the buckets and shims get mixed up together. Here is the "callout" I will refer to below. I will use the lapper pickup tool to pull buckets. A better choice is the magnetic pickup. Stick the pickup tool to the top center of a bucket. And extract the bucket Did the shim come out stuck to the underside of the bucket held there by the magnetic pickup? I used the lapper tool, and the shim does stick to the bucket most of the time. But a powerful magnetic pickup increases the odds the shim will come out with the bucket. What if the shim did not come out with the bucket? You have to go get it. And this is where the MotionPro magnetic pickup is the right size, to stick to that shim on the left, and extract it. Stick the MotionPro magnetic pickup on that shim and extract it. There it is, stuck to the magnet, instead of falling into the motor. Continue with the removal of the buckets where the gap measured was "out of spec" and need replaced. Once you have the buckets and existing shims extracted, next comes the calculation of what shim size should replace the existing shims. For this example, I will be replacing all the exhaust shims and none of the intake shims - intake shims were all within specification. Calculation of new shims Start by measuring the old shims that were removed. Here is a micrometer from Anytime Tools (pn# 201872), it's impressive how accurate and well made it is, for $25. Measure the shims that need replaced to get back into the valve clearance specification. Disregard if the shim has laser etching that says what size it's supposed to be. We don't care what it says it is, we care what it measures. Same goes for every shim you buy, new or used, measure them. Below is the sample calculation. The ideal new shim size is 1.67mm, but standard shim sizes are only available in 1.65mm and 1.70mm. If the 170mm is chosen, the new "valve clearance" is 0.24mm (on the edge of being too tight) or if the 165mm is chosen, the new "valve clearance" is 0.29mm (on the edge of being too loose). What to do? Use shims from Pro X, they have 7.48mm diameter shims in standard sizes and shims in "intermediate" sizes (in between standard sizes). In the calculation above, choosing the Pro X 1.675mm shim (when standard shim sizes are "too gross") will result in a new clearance of 0.265mm, in the middle of the Yamaha specification for exhaust valves (0.24mm -> 0.30mm) . Keep this in mind that there are more choices in shims sizes with Pro X. Since I started using Pro X shims, I buy only Pro X shims. Check with RockyMountainATVMC.com they stock complete Pro X shims kits and sell individual sizes, and they seem to always have any size I need in stock, same day shipping. Use this example and calculate what shim sizes you need to order, and get them on the way (about $2 each from Pro X suppliers- Pro X has standard sizes and "intermediate" sizes for same price). Installing new shims Once the new shims are in hand, use the MotionPro magnetic pickup to insert the new shims. Put the replacement shim on the MotionPro magnetic pickup, with the lazer etching side of the shim stuck to the magnet. Dash the valve "cup"/stem with a small amount of assembly lube. A small amount, not this flood. I had things in and out multiple times and got overboard with the lube. Place the new shim in the valve retainer "cup" securely... Insert the new shim into the retainer "cup", and slide the MP pickup tool sideways, like spreading butter on a bagel, slide the tool right off the side of the valve retainer, leaving the shim securely in the cup. Put all the buckets back in the motor with the same valve they came out of, but with the new size shim. To place the bucket over this valve & shim, use the rubber lapping tool. NO MAGNETICS - if you use a magnetic tool, as you slide the bucket into place the magnet could pull that shim up and out of the cup (under the bucket), and you would not know because you can't see what happens underneath the bucket as you insert it in the head (but you will find out when you rotate the crank to test your timing at the end of maintenance procedure). Wet the rubber cup with a little oil and wet the bucket with a small amount of assembly lube outside, and a small dash of lube inside the bucket where the shim will make contact, and "stick" the rubber tool on the bucket. Any "dry" spots on the bucket, wet with engine oil. and slide the bucket back into the head, you can twirl it between your fingers and it will slide right in. If you use your hand instead of the lapper tool, it will "bind". Let the rubber cup tool be free between your fingers to find it's own way as it slides into place. Continue, replacing the old shims with new, and the buckets matched with the bore in the head they came out of. Once you have the new shims and buckets back in the head, on to Part 3 - Reassembly of the cams. 3 1 Link to comment Share on other sites More sharing options...
Global Moderator Pursuvant Posted February 18, 2023 Author Global Moderator Share Posted February 18, 2023 2203.02 Removed from the maintenance parts list: 0 x 1WS-11169-00-00 Breather Gasket Link to comment Share on other sites More sharing options...
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