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First, I want to note that this is an alternative method of adjusting the valves that doesn't require the use of the Yamaha or Motion-Pro tools. For info on that method, look in the service manual or the links below. This method may not be for everybody, but does offer the advantage of not needing the tool and gives you access to all of the shims at once, making moving existing shims around between valves much easier. Some users have reported only loosening the cam caps (without removing the cams) to gain access to the shims as yet another alternative method, the choice is yours.
I'll also note that it's very important that the bike/motor be level side-to-side. So, without further ado, here it is...
First things first; check and record your clearances for all valves. Remove the cam and timing covers and rotate the motor clockwise while checking each valve. I use a go/no go set of feeler gauges, really handy...
Once you've got all the measurements, turn the crankshaft (always clockwise) until the pointer is on the 'T'.
Do you see these 'dots' on the cams? If you do, they both should line up with the marks on the cam caps, and then turn the crankshaft around one more time (so you can't see them)...
...then remove these two cam sprocket bolts. Turn the crank once more (so you can see the dots again and they line up with the marks on the caps) and remove the other two bolts. Note the little 'points' by the second pair of bolt holes...
...as shown in close-up here. These holes must be on the same 'side' of the cam as the dots or your cam timing will be off. DO NOT turn the crankshaft again until you get to the end of the reassembly process!
Remove the cam chain tensioner...
... which will give you slack so you can lift out the top chain guide. Lift/move the chain to one side and lift it out.
Loosen/remove the cam caps, taking care not to just take them off, but to loosen them gradually so as to not 'cock' the cam as at least one lobe will be holding a valve open. Loosen the cap nuts on either side of those lobes about 1/4 turn at a time. Once you have the caps off, lift up and rotate the cam/sprocket until you can pull the cam out through the sprocket. TIP: use a magnet on/near the nuts/bolts so as not to lose any inside the motor; it really sucks trying to fish those out...
You now have access to all the shims, simply pop them out. I use a knife edge, some use magnets (but I haven't had any luck with those, the oil 'stiction' is more than the magnet can overcome) to get them out.
Check the shim size, which should be etched on the 'bottom' side. To determine your new shim size, check your recorded clearance. I use 'inch' feeler gauges as I've found it's much simpler to calculate shim changes.
Now in this case, all the valves were good except for the two inner intake valves (so I'm not pulling the exhaust cam), both of which are .004". Each shim size difference is .002", and as I want the upper end of the early spec (.008"), I need to go two sizes thinner. Both valves have 270 shims installed, so I'm going to use 260 shims for replacement.
As a side note, I suspect that whoever adjusted these last had a hard time getting to these (the two hardest to work in the bike with the motion-pro tool) so they just skipped them. I'll also note that I'm doing this with the motor on a stand so it's a bit easier, but it's not that much tougher in the bike.
Once you have all the shims replaced/moved to get your calculated clearance, assembly is pretty much the reverse with a few exceptions and things to check. First, lay the cams in so the dots will line up with the caps, although if the dots are a bit to the 'rear' of the cam marks that will help with getting the sprockets on. Once you get the cam caps reinstalled and torqued (again, tighten gradually) and are installing the sprockets back on the cams, make sure the cam chain is properly on the crankshaft sprocket and that the holes in the cam sprockets line up right. If you need to turn the cams slightly to line up the sprocket bolts, do so; don't turn the crank. Install the first two cam sprocket bolts (don't tighten them yet), then install the cam chain tensioner; this is so you can rotate the motor to get to the other two cam sprocket bolts without worrying about the chain jumping. Double-check your cam timing at this time; after rotating it once, make sure the cam dots line up with the caps when the timing pointer is at 'T'. If everything's good, final torque all the bolts, doublecheck to make sure your clearances ended up where you want them, and reassemble the rest...
I'll also note that it's very important that the bike/motor be level side-to-side. So, without further ado, here it is...
First things first; check and record your clearances for all valves. Remove the cam and timing covers and rotate the motor clockwise while checking each valve. I use a go/no go set of feeler gauges, really handy...
Once you've got all the measurements, turn the crankshaft (always clockwise) until the pointer is on the 'T'.
Do you see these 'dots' on the cams? If you do, they both should line up with the marks on the cam caps, and then turn the crankshaft around one more time (so you can't see them)...
...then remove these two cam sprocket bolts. Turn the crank once more (so you can see the dots again and they line up with the marks on the caps) and remove the other two bolts. Note the little 'points' by the second pair of bolt holes...
...as shown in close-up here. These holes must be on the same 'side' of the cam as the dots or your cam timing will be off. DO NOT turn the crankshaft again until you get to the end of the reassembly process!
Remove the cam chain tensioner...
... which will give you slack so you can lift out the top chain guide. Lift/move the chain to one side and lift it out.
Loosen/remove the cam caps, taking care not to just take them off, but to loosen them gradually so as to not 'cock' the cam as at least one lobe will be holding a valve open. Loosen the cap nuts on either side of those lobes about 1/4 turn at a time. Once you have the caps off, lift up and rotate the cam/sprocket until you can pull the cam out through the sprocket. TIP: use a magnet on/near the nuts/bolts so as not to lose any inside the motor; it really sucks trying to fish those out...
You now have access to all the shims, simply pop them out. I use a knife edge, some use magnets (but I haven't had any luck with those, the oil 'stiction' is more than the magnet can overcome) to get them out.
Check the shim size, which should be etched on the 'bottom' side. To determine your new shim size, check your recorded clearance. I use 'inch' feeler gauges as I've found it's much simpler to calculate shim changes.
Now in this case, all the valves were good except for the two inner intake valves (so I'm not pulling the exhaust cam), both of which are .004". Each shim size difference is .002", and as I want the upper end of the early spec (.008"), I need to go two sizes thinner. Both valves have 270 shims installed, so I'm going to use 260 shims for replacement.
As a side note, I suspect that whoever adjusted these last had a hard time getting to these (the two hardest to work in the bike with the motion-pro tool) so they just skipped them. I'll also note that I'm doing this with the motor on a stand so it's a bit easier, but it's not that much tougher in the bike.
Once you have all the shims replaced/moved to get your calculated clearance, assembly is pretty much the reverse with a few exceptions and things to check. First, lay the cams in so the dots will line up with the caps, although if the dots are a bit to the 'rear' of the cam marks that will help with getting the sprockets on. Once you get the cam caps reinstalled and torqued (again, tighten gradually) and are installing the sprockets back on the cams, make sure the cam chain is properly on the crankshaft sprocket and that the holes in the cam sprockets line up right. If you need to turn the cams slightly to line up the sprocket bolts, do so; don't turn the crank. Install the first two cam sprocket bolts (don't tighten them yet), then install the cam chain tensioner; this is so you can rotate the motor to get to the other two cam sprocket bolts without worrying about the chain jumping. Double-check your cam timing at this time; after rotating it once, make sure the cam dots line up with the caps when the timing pointer is at 'T'. If everything's good, final torque all the bolts, doublecheck to make sure your clearances ended up where you want them, and reassemble the rest...
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