Starter Motor/Clutch

Do you currently own a CX650T? In the course of starting your bike, have you ever experienced the engine kicking back while holding the starter button? How about the engine not starting until AFTER you let off the starter button? Does your clock annoyingly reset to 1:00 occasionally while starting the bike? Do these problems go away for a while after you install a new battery, but return at a later time? These are all symptoms of the same thing: starter motor design and wear.

The starter motor on the CX500TC is of a different design and does not exhibit this gremlin. The starter of the CX650T exhibits an amazing amount of mechanical resistance to rotation. If you removed the starter, (a simple two bolt proposition at the lower left rear of the engine) and turned the shaft with your fingers, you would feel a pronounced notchiness and resistance to rotation. Because the starter must overcome this increased friction, it now draws excessive amounts of current from the battery. This in turn lowers the potential to a critically low level. At this point, the clock may reset, and the ignition may have only marginal voltage to fire. While the ignition is half-hearted, the fuel is still being dumped into the cylinders. This causes the engine to kick back sporadically with continued attempts to start it. All the power of these kickbacks is fed directly back into the starter clutch. So, while the starter is trying to turn the engine one way, along comes this powerful kickback pulse trying to turn everything in the opposite direction. The shock of all this commotion is shouldered completely by the starter clutch, which can fail with the repeated abuse of the kickbacks. If even one spring of the starter clutch assembly breaks, you will hear a sickening grinding sound as you turn over the engine with the starter. It may happen each time, or only occasionally. Continued grinding of the starter clutch will, I repeat WILL, damage the end of your crankshaft, necessitating it's replacement. As you can see, many serious problems arise from one precipitous event, the starter motor. The vast majority of the time, the problem is relegated to the first few symptoms, and isn't disastrous until a starter clutch spring breaks. However, I have seen this complete scenario play itself out in its entirety on more than one occasion, so do not underestimate the potential for disaster if all you are experiencing right now is your clock resetting to 1:00. In any case, there is good news for all.

This whole horror scenario can be rectified with a simple starter motor swap. Recall that I mentioned the CX500TC does not have this problem. The motors are different. The black motor casing of the 650 starter motor is smooth, unpunctuated with any phillips head screws. The CX500TC motor casing will be punctuated with four phillips screws about the center of it's circumference at 90 degree intervals. Two are visible, the other two are hidden out of site between the motor and engine. There are several options in starter motor replacement. First, a CX650T owner could order a new CX500TC starter and drop it in. You will have a new machine. It will turn over faster, start sooner and easier, will not kick back, and best of all you will never have to reset your clock again! Hopefully after making the switch, you will be so ecstatic and giddy with pleasure, you can overlook the two or three hundred dollars you just spent on a palm-sized motor. Which brings me to your second option, which will leave you with enough money to order out pizza for your starter motor installation party afterward.

If you go to a salvage shop and ask for a used starter motor for a CX500 Turbo, you will get laughed at. However, ask for a GL500 motor, or an 1980-1982 CX500 starter motor, you will be directed to a bin full of them. These are all drop-in fits with black casings. If all the shop has are 1978-1979 CX500 starters, these are also identical drop-in fits, except the casing is grey. Simply disassemble the casing from the ends and paint the casing black. Naturally, check that your prospective motor has the four large phillips screws mentioned previously, and spin the shaft to check for smoothness; it should be butter-smooth. If it does not have the four phillips screws, you have a GL650 starter. Keep looking.

A quick mention was made earlier of starter clutch springs breaking from the abuse of continued kickbacks. The starter clutch consists of three springs, three plungers, and three rollers which ride along the starter driven gear, which rides on the end of the crankshaft via needle bearings. The actual clutch assembly is located in the flywheel which attaches to the end of the crankshaft. If the springs are not broken, obviously one would not remove the engine solely to replace them. However, if EVER the opportunity should arise that the rear engine cover is removed, (and it WILL, I guarantee it. More later...) remove the flywheel, pop the rollers and plungers out and spend a few bucks on three new springs. If you get this far and one or more plungers is jammed up into the clutch housing, one or more springs have broken, and you have probably been experiencing grinding noises upon start-up. In this case, all you can do is hold your breath and cross your fingers as you closely examine the area of the crankshaft which the needle bearings ride on. Any surface texture other than perfectly smooth indicates damage from engine kickbacks through broken starter clutch springs. If you have not breathed a sigh of relief after examining the crankshaft, wipe your tears, take a deep breath and ascertain the severity of the damage. If the spring(s) recently broke, you may be able to dress the damage enough to put it back in service as I did. If, on the other hand, you have been hearing grinding noises upon start-up since last year, get ready to begin a night job to pay for your shiny new crankshaft.

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