The Auto Cam Chain Tensioner (ACCT) has had some failure issues over the different model years.. The current version (2003 and later model years) has not seen as many failures in DRZ's but has seen some failures in other Suzuki models, as well as similar designs in other brands of bikes and ATV.. Even without catastrophic failure it still puts too much constant pressure on the chain, causing excessive wear. With the history, and continued issues of previous and current designs.. Many replace the ACCT of all years with a Manual Cam Chain Tensioner (MCCT). There are two choices as of this writing... One is the MCCT from APE. It was the first one on the market and has been is used with good success. The APE design works, but has never been updated. The other choice, and the newer design is made and sold by our very own TT shop..... Thumper Talk MCCT This design not only looks better, it has additional sealing features the APR does not. The TT MCCT has taken the best designs features of MCCT's that came before it, combined them in to one great design.
Install of a Manual Cam Chain Tensioner
The procedure is so easy many are confused by it. If you can check your valves, you can install the MCCT.
Basic tools are needed for the installation.
1: Rotate the motor to TDC on the compression stroke by removing the spark plug, remove large access plug on left side cover, small access plug on top of left cover, rotate motor in normal direction, stop when cam lobes are pointing at 10 & 2’oclock and the flywheel timing index line is centered in the window.
And flywheel index line in the center of the sight window
NOTE: Many have questioned the need to rotate the motor to TDC before removing the ACCT. Two reasons to do so.
1: I have no idea who is reading this write up. SO it was written with the most fool proof method of install I could come up with.
2: When the cams are at any point but TDC on the compression stroke, one or more lobes are pushing down on a valve bucket. When you release all tension from the cam chain, the cams can rotate under force from the valve spring. This could cause the cam chain sprockets to skip a tooth on the chain. Many would not even recognize if or when that cams rotated, let alone understand that while no damage has been done YET, they do need to check the cam timing now.. If you put the motor at TDC, none of this is an issue. Want to skip this step... no worrys,, though really a few seconds to rotate the motor to TDC can save you the hassle of checking the timing if/when the motor snaps over when you allow chain tension to go slack.
2: Remove the oil vapor recover tank bolt, push the tank out of the way.
3: Remove the two hex head cap screws holding the ACCT to the motor, remove the ACCT and the OEM gasket.
4: Install the MCCT, reusing the two OEM screws and the O ring supplied (or new gasket if that is the style MCCT you are installing)
6; Loosen the lock nut and back the lock nut and o ring (if your MCCT has one) well back on threaded MCCT shaft.
7: Tighten the MCCT shaft just until it touches the cam chain guide. Finger tight is all your looking for.
8: Start the motor, back the MCCT out until you hear a distinctive rattle from the cam chain/ guide.
9: Tighten the MCCT JUST until the rattle goes away. Think of it as tuning a dial type radio. Out a little, hear the rattle, in a little rattle goes away… STOP.. Your done adjusting. DO NOT add a “little” more just to be sure, DO NOT give it another ¼ turn,,,,, YOUR DONE ADJUSTING. Hold the MCCT main shaft in place, move the O ring up to the body, screw the lock nut all the way to the body and tighten. Locking the MCCT in place.
10; Congratulations your done. Go ride. Chances are you will never have to readjust the MCCT. If the cam chain is already stretched, if the motor is torn down to the open case level, or you have some other major motor failure, you may need to re adjust the MCCT. Or if you put thousands of miles on your motor, it may need to be adjusted. Other than that, resist the desire to “adjust” the MCCT. If properly installed, there really is nothing to mess with under normal running conditions. No regular maintenance required. If you do find your MCCT need further adjustment (tighter) you probable have a chain that is stretched and worn out.
