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Welcome to Transworld Motocross How Tos presented by BikeBandit. Having the right shim clearance in a bike is very, very important. It helps starting, it helps running, it helps on decel and it’s something you should definitely check once or twice a year. So we’ve got this Kawi 450 apart here, doing a top end on it, and we’re gonna check the shim clearance. I’ve already gone ahead and used these Motion Pro Shim tools to check the clearance and this is what you should do after you figure out where you’re at on each of the four valves. [inaudible 00:00:45] here. I’ve taken the subframe off, the shock off, at least removed the shock a little bit, taken the carburetor off, you can let it hang down here. I’ve drained the coolant, taken the motor mounts off, tank obviously. You wanna get everything as much out of the way as you can to start, it makes it a whole lot easier coming down the road. So, what you can do now is simply remove the valve cover. Careful of that gasket on the top. Usually you can reuse this top gasket, it just stays on there. Come around to the side of the bike. You’re gonna wanna…you’re gonna have to time it, so remove your timing covers here and here, as well your cam chain tensioner bolt, and there’s always a little O-ring in there, I’ll get that in a second. And then now you’re ready to actually start taking it apart, but first you must find top dead center.

All right, bolts are out of here. Now, sometimes it takes a little bit of force to…I just like to tap it with a T-handle, kinda break the seal between dowels. And on Kawi like I said, you are gonna want to keep it together and watch your dowels. Always watch your dowels. So oil lines off and the cam caps can come off. See right there, one of the dowels came up on me. So again, just be careful of that. Drop it back into it’s hole where it’s happy. And this one came off. One with a cap, one still in the head, but that’s fine just pay attention to ’em. So we’ve already found top dead center but you need to find it as well to measure your valves. So I just simply find top dead center. I always put a T-hand [SP] or a screwdriver down in there, take the spark plug out. So we are… Right there is top dead center. The cam chain tensioner needs to be loose. Simply get your screwdriver, stick it in the hole and turn it clockwise and take the tension out of the chain. Now on this particular model, the exhaust .17 to .22 clearance and the intake is .10 to .15. As you can see on the board, the exhaust I’ve measured is .17, so we’re within spec, and the…but the intakes are tight, .19 for one, .07 for the other, .09, .07 for the other. Now this is a ginormous piece of paper but just get a smaller piece and write down each valve and what you’re measuring to keep track and make it easier for you later.

Okay, so the intake cam has been removed and now we’ll take the bucket and the shim off and see what we have. Just gently grab the bucket up with a pair of pliers. Sometimes the shim is stuck in there but on this one, the shim is in the bottom of the bucket. All right, so I’ve got the buckets and the shims here and I’ve lined it up. This is the left-hand exhaust, this is the right-hand exhaust as it’s sitting on the bike. Due to wear and tear, you can’t see the number on the shim anymore, so this is where your caliper comes into effect. It’s a 2.5 shim, the left one is. The right one, 2.5 as well. So, one three, that’s right in the middle of the recommended range for the intake. We’re at .07 on the left, .09 on the right. So we need to go up approximately .05 in the shims. We have 2.5 millimeter shims in there. Add 4 to that, which would bring this up to 11 and this up to 13. Add four to that and you’re looking at plus .04, you’re looking at a .29 shim or a .30.

All right, so we’ve got a shim kit here from Hot Cams and you can pick that up from them or you can get it…a bunch of retailers have shim kits, so fits nicely in here. Like I said, we need a 2.9, can’t get that, so let’s go with a three. We got a three shim and it’s marked three. And we’re gonna install the three shim on top of the valve and that should be perfect for what we need. All right, I’ve got the new shim, I’m gonna drop that in the top, on top of the retainer. Push it down in there. Get a little bit of oil, just coat the sides of the buckets. When you’re reinstalling, again, make sure you have the left and the right sides correct because it does matter. Push the bucket down in there. This is the shim over bucket system they call it, obviously. And then now we’re ready to install the cam.

We have found top dead center, so we’re all good there. Now we simply need to install the cam. And just bring it towards you, tilt it a little bit of an angle to help yourself get on the chain. And I can see that I’m one tooth off as opposed to being level with the top of the cylinder head. So I’m gonna take the cam back out and just take the chain off and move the cam one tooth down, and we are level with the top on the exhaust and the intake. We’re at top dead center in the piston, so we’re good to go. All right, I’ve got the retainer clips. Exhaust one is in, put this one in the intake. Careful not to drop them. Those basically hold the cam in place. This Kawasaki, the Kawasaki has an O-ring underneath the spark plug cam, so it just drops right into that little groove right there, don’t forget that. All right, with business being accounted, we have some oil passageways there and install the Kawasaki all as one happy family together. Basically drop it in there. Let it find a home with the dowels. Put the oil lines together and there we go. All in there.

Time for the bolts. They’re installed here. These need to be torqued properly. I can’t stress enough you need to torque the cam caps as well as the cylinder head bolts correctly, so what I like to do is just get them finger tight here and then the correct amount of torque is eight foot-pounds. I’m not gonna go eight for each one, I’m gonna do a four each one and then increase to eight, but…as well. So we got four foot-pounds. Crisscross these bolts. I like to start in the middle and then go outwards, but crisscross at four foot-pounds each. Very important to torque these bolts. I’ve seen damage from overtightening, I’ve seen damage from undertightening. You can ask my buddy, he had to lay out about $400 because he overtightened it, my buddy Trevor. [inaudible 00:09:02] now. All right, so we’ve got four, now let’s do eight. Set the torque wrench, and again, same pattern. Start on the inside, crisscross, and we’re at eight foot-pounds of torque. One thing I should mention that maybe we didn’t talk about too is I greased the journals of the cam caps as well with oil to help the initial startup, the initial break in of the top end that we did earlier, and this is just for shimming valves. So, take the cam chain tensioner, break it loose, cam chain is tight. Now let’s check and see if our measurements were right.

All right, now we’re ready to see if we are where we’re at and where we’re supposed to be for the proper amount of clearance. So I’ve got a feeler gauge here. Let’s try to get a .10 in there. Basically, you have it set where the lobes are across from each other at top dead center. You just wanna stick the feeler gauge in there and see if there’s room between the top of the bucket and the bottom of the lobe. And as you can see, there’s plenty of room there. So I know this one’s a little tight but it’s looser than a .10. And we know from our measurements that the intake is .10 to .15. So we know now we have enough measurement, but do we have too much measurement? Let’s take a look. Here we have a .15 feeler gauge, put that in there. And nope, it will not go through between the bucket and the lobe. Same thing on the other side. So we know our measurement and we can go precise. Just for giggles, let’s try a .13. And a .13 goes through on the left, does not go through on the right, but we know a .10 does. So our right-hand intake valve is between a .10 and a .13, somewhere in there. It’s either .11 or .12, but we’re well within in range and we know a .15 won’t go in the left one but a .13 did, so chances are we are at .14 on the left intake valve. Either way, we’re within spec on the…what the owner’s manual calls for and you’re ready to go ripping. Don’t forget, put spark plug back in, put the valve cover back on and you’ll be ready to go. That’s this week’s Transworld How To, presented by BikeBandit, shim adjustment.



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