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How To: Adjust Valves FZ-07 MT-07 XSR Tenere (Part 3)


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<-- Part 2

'continued from Part 2

If you have been following Part 1 & Part 2, your motor crankshaft is already in the correct position for removing and reinstalling cams.

 

Essential Knowledge

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).

xlsxTimingDiag.thumb.jpg.9be04ec39c9c7dbb39e7a79f2a56b5df.jpg

 

If the crankshaft has not been turned since the cams were removed, a check of the rotor flywheel timing marks will be in alignment, exactly as they were set before the cams were removed - aligned properly and with cylinder #1 TDC Exhaust Stroke (RED timing mark added for clarity).

Essent.RotarTimingMark.Aligned_02.jpg.21647f31af8e46b821258aac81388363.jpg

 

Sketches are views from the "RIGHT" side of bike (foot brake side). Putting the motor in time, is a sequence of steps starting at the crank cam sprocket and working counter-clockwise to remove cam chain slack and align timing marks on the cams, and the final step of installing the cam chain tensioner and adjusting to remove remaining slack. In these sketches, the RED color indicates where the cam chain slack has been removed during reassembly.

Assembly_Cams_01a.thumb.jpg.b38cce4b85e1665c70a7365a7faf2c3e.jpg

 

Keep a clear understanding that when viewed from the "RIGHT" side of the bike (foot brake side), the running engine will turn clockwise. The crank cam sprocket turning clockwise will pull "down" so to speak on the exhaust cam and in turn pull the intake cam sprocket, the cam lobes opening and closing valves in time with the crank motion of the pistons without self-destructing. Before the valve cover goes back on, it is easy to confirm the motor is in time by simply checking the involved timing marks, rotating the crank one full 4 stroke cycle (720 degrees) and checking them all again. And then check them again, and take pictures to send to anybody who cares, that you do your own valves. It is also obvious if the motor has not been put in time. If the cam sprocket timing marks are off by even one tooth, it is visually impossible to ignore - you will know it. The most dangerous thing (imo) is not mistiming the cams, it's dropping something "hard" into the motor.

AND 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.

The 4 sketches above result with the drawing below, where the final step of setting the cam chain tensioner is complete. This is a motor in time, and if any of your timing marks are not aligned with the engine case as shown below - no harm done, other than you get to go backwards removing the cam(s) to get to the step where the first misalignment occurred.

Assembly_Cams_01b.jpg.34b6eb3151426133e803602c199f23be.jpg

 

Prerequisites:

SEE THE YAMAHA SERVICE MANUAL. Use assembly lube on the cylinder head journals (where the camshafts "sit" when operating), the valve buckets, the cams, cam caps - all the "metal to metal" contact surfaces where movement occurs. What does not get assembly lube can be wetted with engine oil. Refer to Yamaha documentation. WET THE CAM CAP BOLTS because the torque specification is intended for bolts that have been lubed on the bolt threads with engine oil.

Position key tools within reach, and set both the cams on top of the cylinder head but back out of the way of the chain until they are needed (do not place them under the chain yet). You want everything lubed and ready to go (easily in reach) because you will be maintaining mild tension on the cam chain with one hand (starting with the chain between the crank cam chain sprocket and the exhaust cam).

My disorganized organization - as long as your brain knows what is what, you're good.

DisorganizedOrganization01.jpg.a449ea2672e04cd7eea32d3103e19be6.jpg

 

Pick up the cam chain with both hands, like a necklace. Shake the cam chain a bit, and it will "free up" a little more chain that may have been caught on the cam chain guides (important, even if you kept the chain on the cam sprocket, there still can be some chain entangled with the chain tensioner guides). Raise the chain, and you will feel it when it slides back on the crank sprocket, its a very secure fit. Don't try to muscle the chain, if you pull hard-hard you might turn the crank that is aligned for reassembly. You just keep a relatively small amount of tension on the chain. That results in a cam chain back on the cam chain crank sprocket (in RED).

Cam.Timing.a_01.jpg.e9f8848c6c94d9eb87f28efc2fd73a4a.jpg

Most of us only have two hands, so if you're not a squid lets tie up some of that chain so it's less likely to slide off the crank sprocket. Leave enough chain free to work on the next step, setting & timing of the exhaust cam. Below shows the extra slack taken up by a zip tie, and the right hand is holding enough of the cam chain to keep it on the crank cam sprocket.

Cam.Timing.b_01.jpg.9b3a6eb639e77917f624b147db7f2aed.jpg

Always while working to set the cams, be conscious of keeping some mild tension on the cam chain. It's not like it has to be tensioned every moment - I often let some slack into the cam chain while working on cams but by keeping it moderate, the cam chain stays on the crank cam sprocket.

Next step, set the exhaust cam. First take a clear look at the exhaust cam and it's timing marks (out of the bike). There are two timing marks, one at "12" and the other at "6".

Cam.Timing.c_02.jpg.d8830eae1e50cbee29c45b6c826d2afe.jpg

 

They will be aligned with the top of the engine case like below when the cam is set in it's journals where it rotates.

Cam.Timing.c_04.jpg.e003bdd1244bf1a8dd247d1a4bc85947.jpg

And when positioning the exhaust cam, because it has two timing marks - you can ensure proper position of the exhaust cam by checking the view from the "LEFT" side of bike (gear shift side) cylinder #1 cam lobes "FACE EACH OTHER" (or better said, they will face each other). Below is a picture of both the cams, facing each other, as they are when in proper position for removal and and how they should be aligned during installation of the cams. You will align the timing cam gear marks with the engine case, and make sure the exhaust cam lobes on cylinder #1 are oriented to "FACE EACH OTHER" once both cans are in place.

IMG_CamLobesFaceEachOther01.jpg.f10f2255bb9c76167dab0ab5083d7980.jpg

 

Let's begin the install & timing of the exhaust cam. We want to find the cam chain "rivet" (I will call it the "pin") that is in alignment with the top of the engine case, when the exhaust cam is positioned. I'm holding the chain (with the slack removed in my hand) as if it was wrapping around the exhaust cam gear, and that identifies the pin with the RED arrow as our target for cam alignment (the picture is taken from above and that distorts the view somewhat).

Cam.Timing.c_03.jpg.24902928e64ed1ad52d80ee0c5ffbc51.jpg

Let's use a diagram to show it at the top of the engine case "eye level". The chain is coming off of the crank cam sprocket and is snug with no slack, and the RED pin identifies where the exhaust cam timing mark needs to point (it should point just above the top of the pin just like the engine case does).

Cam.Timing.c_05.jpg.7141fcead0605ed2cf6adbec817ccaba.jpg

OK, so without losing track of the RED pin or creating any slack in the chain, hold the cam above where it will eventually sit and take the cam chain (with slack removed) and wrap it around the exhaust cam sprocket, with the timing marks on the exhaust cam pointing at the top of the RED pin like below. (Sorry, I can't draw "gear teeth", so the gear below is just the circle with the two timing marks.)

TIP: I have heard you can use "white out" from office supplies, and put a small dab of white on the pin - and wipe if off once complete. You can also use "mechanics pen" (Forney White Paint Marker #70818) that is oil based - but my old eyes can't see it very well.

 

Cam.Timing.c_06.jpg.65d0b63b7541e0bbbdfce29ce5dc9ef7.jpg

And without letting the chain go slack (as you lower the exhaust cam down into the journals you must rotate it by hand, a small amount counter-clockwise to keep the cam chain tensioned with no slack), setting the cam into it's journal seats where it belongs in the cylinder head, with the timing chain wrapped around it, without any chain slack between the crank cam sprocket and the exhaust cam gear.

See what we did ? - we used the cam chain off the crank cam sprocket to "measure" where the exhaust cam timing mark needed to be relative to the cam chain, then put the exhaust cam into the cam chain at that position before we lowered it into place in it's journals.

 

Cam.Timing.c_07.jpg.5318213cbe0c03e98b008800837b940b.jpg

 

The cam timing mark may be a little "high" (slightly above the engine case) because it needs it's cam cap bar to "seat" itself down a little further into it's journals properly. Take the lubed up exhaust cap bar (and read the Service Manual how to lube the cap bar bolts before inserting) and start the cam cap bolts in by hand. As described in the service manual, tighten down the exhaust cam cap bolts a small amount at a time, working from the outside to the inside, in a crisscross manner. ONLY SNUG THE EXHAUST CAM CAP BOLTS LIGHTLY  - you want them secure so things don't move but don't put any real torque on the cam cap yet.

FOLLOW THE SERVICE MANUAL INSTRUCTIONS FOR LUBING AND SEATING ALL CAMS, CAPS, AND PARTS.

 

With the exhaust cam set in the head, the cam is both timed properly and it has no slack (indicated by the RED outline on the cam chain) below.

Cam.Timing.c_01.jpg.137780bd9e1b94a0b001ab5220f6b18f.jpg

Nice. Now let's do the install & timing of the intake cam. If the cam chain can be used to measure where the exhaust cam timing mark needed to "point", it can also identify where the intake gear timing mark should point relative to the cam chain before the intake cam is lowered into it's journals. I already know how many cam chain rivets ("pins") away from the exhaust cam timing mark, the intake pin should be on the chain. We are going to simply count from our starting position of the exhaust cam timing mark pin, and that will identify where we want the intake gear timing mark to point.

 

Cam.Timing.d_02.thumb.jpg.b3c11509d01164fa4c609bf1b106711f.jpg

 

On the exhaust cam chain, start counting from our PIN #1. Count 31 "pins" (see Count Timing Chain Pin Links in Part 2). Place the intake cam on the cam chain with the timing mark (stamped with the capital letter "I") between chain PIN #31 and PIN #32. Now set the cam in place, without slack in the chain between the two cams, above the intake cam seats in the head.

Because the intake cam has cam lobes pointing "downward" toward the buckets, the intake cam gear timing mark will appear too high above the engine case until the cam cap bar pushes the cam down into the intake cam journals properly (and it will open some valves as the cam cap is tightened). Not yet, but when we are ready, the intake cam cap bolts will be tightened enough to seat the intake cam, and the intake timing mark "I" will then align with the cylinder head. Place the intake cam cap bar on the cam, put the bolts into position but just turn them by hand a turn or two - Important! Don't try to push the intake cam down yet (enough to open intake valves) with the cam cap bolts! Just position the intake cam cap bolts by hand-tightening.

BEFORE DOING ANYTHING ELSE STOP and do this. When the initial tightening down of the intake cam cap is applied, it will cause the timing chain around the exhaust cam gear to start to "walk" out of the cam gear (trying to slip a tooth). You can see this chain "walk" in pic below.

Cam.Timing.e_01.jpg.b8ac8ccf6d9e141fad93ac6a3205beda.jpg

To prevent that from happening, we are going to proactively "bind" the cam chain to both the exhaust and intake cam gears so they can't slip a tooth, and we use a different method on each cam.

To bind the exhaust cam sprocket to chain, you want to make a small "wedge" using some vacuum line, and run a safety wire or string or other (I used lawn trimmer line) thru the center of the vacuum hose. Make the line long enough that if you drop the wedge into the open motor you can easily retrieve it.

Cam.Timing.e_02.jpg.d0f57337fe3a9487bd21f9c8b8513c87.jpg

"Wedge" the vacuum line cushion down in-between the exhaust cam chain & engine case, and tie the safety line off anywhere handy. It should be hard to get it wedged in place - that's good, it needs to apply some force to the chain, pushing it onto it's cam gear.

Cam.Timing.e_03.jpg.9501572e85ea9661e4ddfff551cd483e.jpg

Cam.Timing.e_04.jpg.71c56d3c073ce5fd9ff50d9c719d38f1.jpg

That vacuum line is the right size to wedge with enough force to keep the cam chain on the exhaust cam gear.

To bind the cam chain to the intake cam gear, follow the directions in the Yamaha Service Manual for putting a zip tie around the chain and thru the "hole" in the intake cam chain sprocket (we could not do it that way on the exhaust cam gear because it has no bore "holes" in the gear to run a zip tie through). Put the zip tie through the cam gear and tighten it down to tie the cam chain to the  cam gear - easy and effective way to prevent the cam chain from slipping a tooth.

EDIT 2023.02 new picture of intake cam gear/chain bind with a ziptie

 

IntakeZiptie02.jpg.d06d663d246d81f0f3c2ed1047463fe2.jpg

Once both the cam gears are bound to the chain to prevent a skipped tooth, we can continue with the intake cam installation, following the Yamaha Service Manual.

This intake cam is still "up above it's journals" (not seated into position) and has a little way to go down as you tighten the intake cam cap bolts (tightening the cam cap will be pushing the intake valve buckets "down" to open valves as you tighten), so go slow, tighten the intake cam cap bolts in small amounts at a time working from the outside in with a crisscross pattern, to bring that cam and cap down into the seats in a level, even fashion. Seriously, go slow in small increments. If you don't bring the whole cap down in small steps, you could "twist" the cam cap badly. ONLY SNUG THE INTAKE CAM CAP BOLTS LIGHTLY.

DO NOT REMOVE THE CAM CHAIN BIND TO CAM GEARS UNTIL AFTER THE CAM CHAIN TENSIONER IS REINSTALLED.

Now, before applying the proper torque to the intake and exhaust cam caps, look at both the cam gears to confirm the timing marks are aligned with the cylinder head correctly. Go back to the pictures you took of the cam alignment before they were removed. Check the exhaust cam timing marks with a straightedge. The intake cam timing mark is easy to see, with the big letter "I" next to the timing mark. If it all looks good, refer to the Yamaha Service Manual and torque both the cam cap bars now, starting with the exhaust cam first. If the timing marks are not aligned, you probably already thought something wasn't right and now you can see. Go backwards in the process, and do it again, making what ever corrections you think are needed.

Here are some pictures I took just before removing the cams (it should be right back where we started):

IMG_ExhaustTimingMark03.jpg.324cbb0e568f9ec89a4e4130b818d39f.jpg

Exhaust cam I highlighted the picture of the two timing marks in red - straight edge really helps see alignment

IntakeCamgearTimeMark01.jpg.1396cbabe9aff549125cc9c5cb8590e9.jpg

and the intake is easy to see that it is aligned, even though my photo is from "slightly above".

Get your eye down at the level of the engine case, and confirm those cams are in time, before going on with reassembly.

 

Reinstalling the Cam Chain Tensioner and Not Following the Service Manual

When the cam chain tensioner is installed it seems that it can "slap" the chain and knock the cam chain enough to throw a skipped tooth into the chain on one of the cams. But if you put binds on both cam gear/chains, it will not skip a tooth. So we are good to go with re-installing the cam chain tensioner.

Retrieve the cam chain tensioner - it should be where you put it along with that special tool still inserted, keeping the chain tensioner retracted. If the special tool came out, just insert the special tool again and retract the tensioner by turning it counter clockwise until it stops - the fully retracted position.

Follow the Service Manual and lube up the tensioner body with engine oil, and the tensioner arm - it is bathed in pressurized oil when it operates with engine running. Insert the tensioner into the cylinder head (with the special tool still inserted in the tensioner). Use a new tensioner gasket if you have one, and follow the Service Manual - it shows that the gasket is inserted in a certain way. Also the cam chain tensioner has a "colored dot mark" on the body of the tensioner showing which side faces up, when it is inserted.

CCT_cyl.opening.jpg.a20ac6e28f2d64fc6693eb434ae46138.jpg

The cylinder head opening has an oil port visible on the "in" side of the bore, and that's why it has to be installed (along with it's gasket) oriented as described in the Service Manual.

specialtool03.jpg.cc4598afe9c2b277cfb0847d2e68ca85.jpg

With the special tool still inserted, remount the cam chain tensioner with the two outer mounting bolts, torque to Service Manual specs.

Now we are going to do the initial tightening of the tensioner arm against the cam chain (the last part of the cam chain that still has slack). Follow the manual up to the point where it says to tightened the cam chain until it makes contact. Now do this instead of following the manual.

Turn the special tool clockwise to the point where it makes contact, then snug the cam chain tensioner with some low-to-medium force - don't gorilla it and definitely don't follow the Service Manual (I think it says "turn it an additional half turn" - a great way to over tighten it imo). Just snug the cam chain tensioner up moderately firm against the cam chain guide with the special tool.

Then take your thumb only, and press hard on the cam chain where it shows in the drawing below, between the two cam gears, and then release. You will see the deflection of the chain when your thumb is pressing down.

Reassembly_Cams_01.jpg.31b901cad9f115fa7abed612b79776a0.jpg

Now try to tighten the special tool that was already snugged with low-to-medium force. It will probably be easier to turn again for a small distance because you freed up some chain slack, so go ahead and repeat the tightening with the special tool. Snug the cam chain tensioner up with low-to-medium force again.

Then repeat - use your thumb again, and press hard again on chain between cams, then release. You will see the deflection of the chain when your thumb is pressing down, but it will probably be less deflection than that first press. Now try to tighten the special tool again - it will probably be easier to turn again, so go ahead and repeat the tightening with the special tool. Snug the cam chain tensioner up with low-to-medium force again.

Each time you press on the cam chain with your thumb (and you see deflection in the chain), there is more chain slack remaining that you free up, and then remove by tightening the special tool again. But it will probably only need 2 presses & tightening. By the 3rd press, you may see very little or no deflection when pressing down on the cam chain. When that happens you are done "pumping" the cam chain for slack. But always check one last time to see if the special tool has been tightened "snug" against the cam chain guide with low-to-medium force.

If you are more comfortable following the Service Manual, please do. You should always follow the Service Manual.

Remove the special tool, and that lets the cam chain tensioner "snap" into auto-tensioning position. Then put the special tool access cap bolt & (new) washer back on the cam chain tensioner, and save your special tool in the toolbox.

After the cam chain tensioner "snap" into position, you can REMOVE THE BINDS PLACED ON THE CAMS/CHAINS. Cut off the intake cam zip tie and pull out the exhaust cam vacuum line wedge, and don't let any pieces fall into the motor.

 

Confirming Cam Timing

To get this far, you have already confirmed that the cam timing marks are all aligned properly, and the cam chain "pin count" between timing marks is correct. But do this final confirm by rotating the engine and bringing it back to the "Cam Rotation Degrees 360" in our crank chart.

xlsxTimingDiag.thumb.jpg.9be04ec39c9c7dbb39e7a79f2a56b5df.jpg

From the "LEFT" side of bike (gear shift side) turn the crankshaft slowly counter clockwise 2 full turns and at the end of the second turn align the rotor flywheel timing marks again (RED timing mark added for clarity).  If you feel any unusual contact or resistance while turning, stop and assess the situation.

Essent.RotarTimingMark.Aligned_02.jpg.21647f31af8e46b821258aac81388363.jpg

Now ensure proper position of the cams by checking the view from the "LEFT" side of bike (gear shift side) cylinder #1 cam lobes "FACE EACH OTHER".

IMG_CamLobesFaceEachOther01.jpg.f10f2255bb9c76167dab0ab5083d7980.jpg

And now check the cam gear timing marks by checking the view from the "RIGHT" side of bike (foot brake side).

IMG_ExhaustTimingMark02.jpg.930a52e36a4114e7e277ab3ee84cb4cb.jpg

IMG_ExhaustTimingMark03.jpg.3cb2e543aee1acb06bfb82785011a270.jpg

IntakeCamgearTimeMark01.jpg.94f207e91a404c2107daa2dd0da4db3e.jpg

And do another "pin" count to confirm the correct position of the intake cam timing mark relative to the cam chain.

If everything looks like the pictures you took before you removed the cams for maintenance, and the cam chain pin count is correct, you are done with the CORE VALVE ADJUSTMENT. Now get that naked bike back together and go ride.

Enjoy.

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2203.02 expanded section on cam chain pin counts and and linked to part 3 how to use when aligning cam gears timing marks.

added hot links within pages for references to other sections. lots more edits and wordsmithing, it's pretty good and created for new riders that want to save $$$ every other year for life

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