Post by grizld1 on Mar 30, 2008 14:45:12 GMT -5
Michael Morse and Bill Getty (JRC Engineering, US distributor for Sparx) have involved me in a project to simplify installation of the Sparx permanent magnet alternator systems. For those with a bit of wrenching capability, the systems are available now in two forms, a single-phase unit that'll fire you without a battery (but can also be used with), and a 3-phase system with enough output for your electric handwarmers, etc.
The system has other advantages. The Sparx rotor keeps the rotating mass closer to the centerline of the bike, improving handling. The assembly (rotor, stator and stator mount) is also about 1.25 lbs. lighter than the OEM assembly. Here's the installation drill.
Mounting
In present form, you'll need a bit of hardware and know-how (though Bill and Michael are working on that). Remove the OEM stator, and remember that the stator wiring bundle is retained by the shift shaft guard. Loosen the engine case screws holding the guard in place and remove it to extract the wiring. Tap the stator screws loose with a hand impact driver (hammer-powered, not air-powered!), separate the stator wiring connector, and remove the stator.
To remove the rotor, either spin the nut off with air impact or put the bike in gear, screw down the rear brake adjustor until the rear wheel is locked or put a foot on the brake pedal, put a cheater bar on your breaker handle, and turn. Then remove the rotor with a proper rotor puller (not a jaw-type gear puller!) Then install the Sparx rotor on the shaft. As with most aftermarket parts, a little hand-fitting was called for on my unit, as the back of the keyway was a touch too narrow for the key. A few strokes with a file took care of it. You'll need a 1" (25 mm won't do it) socket to torque the Sparx nut down.
The stator mounting bracket comes next. It slides into the crankcase stator castings and mounts to the same holes as the OEM stator. The long OEM 6mm screws must be replaced with 25 mm length. Finish seating them with a hand impact tool.
To fasten the stator to the bracket, 3 8mmX1.25 pitchX40mm long screws are required. After installation, the air gap between rotor and stator must be checked with a feeler guage, as per the instruction sheet supplied. Mine bolted up first time with adequate clearance all the way around.
Marking
The Sparx kits come without TDC or timing marks scribed. I fabricated a template for Michael and Bill after degreeing mine in, and if keyway location etc. show to be consistent, they may send out the kits with TDC and ignition timing marks punched. For those of you who can't wait (or who realize that even the OEM marks are often out by 2* or more due to keyway cut and other manufacturing variations and want to know exactly where you are), here's the drill I used.
You'll need a TDC locator--not the "whistler" type or a hard-stop type, just a simple plunger and sleeve. Holeshot used to offer a good one but it's not in their current online listings. If what you wind up with has a spring on it, get rid of the spring. You'll also need a degree wheel; Domi Racer has a nice one, and I think you can download a printable one on Michael's Vintage Brake site which you can apply to something stiff.
Put the bike on a lift, in gear, with the rear brake adjustor run down for enough resistance that the wheel holds position when you turn it enough to remove drive train lash. This will be useful in getting the engine to cooperate in turning, damping the effects of valve spring pressure and flywheel when you want to hold position.
Remove the left side tappet covers. Using a wrench on the rotor nut, turn the engine over by hand, observing the rocker and valve action. When the exhaust valve is closed (rocker up, tappet loose) and the intake is open (rocker down, tappet tight), the left cylinder is falling on the intake stroke. When the intake rocker lifts all the way, the piston is rising on compression. This is where degree readings are taken, to avoid fouling the locator in the valves. Rotate a quarter turn, and install the TDC locator in the left sparkplug hole. Due to the angle of the plug hole, TDC locators tend to take enough sideload to lock up when the piston's rising, so keep the locator free with one hand and turn the crank CCW with the other until you find the highest point on the plunger. Choose one of the radial lines scribed on the rotor (I used the one pointing up) and paint mark it. Then make a temporary mark on the stator (I used the upper surface). This shows approximate TDC.
Next remove the indicator plunger, leaving the sleeve in place (if not removable, block it in raised position with a small hose clamp, O-ring, etc.) Remove the Sparx rotor nut. Stack enough washers on the crankshaft to install the OEM nut without running out of thread and torque to 30 ftlbs. Align the rotor mark with the temporary mark. Install the degree wheel over the nut and secure it with a second nut, installed at a firm finger tightness without allowing the crankshaft to turn. Fasten a piece of wire down with a screw in a case cover mounting hole and align it to point at the 0 mark of the degree wheel.
Install or free the indicator plunger. Reach behind the degree wheel, making sure not to contact it, with a 17 mm. wrench, and rotate the engine CCW, keeping the plunger free as you go. When the lowest piston drop you can read on the indicator is reached, look at the degree wheel and record the reading ATDC. Then pull up the plunger, rotate CW past TDC until the same drop point is reached BTDC, and record the number.
True TDC is at the midpoint. For example if ATDC drop occurs at 40* and BTDC drop at 30*, the TDC mark should be moved 5* toward ATDC, so that the measured drop will occur at 35* both before and after. Turn the crank CCW till the pointer shows 5* past the 0 mark, remove the degree wheel, and make a corrected mark. Reinstall the degree wheel as before and verify the new mark. Once you get a consistent result (it may take a little practice), set a straightedge along the rotor line and scribe a line into the stator. Then use the same procedure to locate ignition timing marks with the retard mark at 15* BTDC and advance at 40* (or wherever your best setting is--my engine favors 37*). Verify before marking and after.
Wiring
One quirk of the Sparx system is that it has no provision for a signal that's usable by the safety relay. To bypass early SR's, remove the relay, clip off the connector, and splice the red/white wires together, restoring power to the solenoid. Later SR's (2 relay domes) also turned the lights off until the alternator signal was picked up. For these, splice the red/white wires as above, and also splice the red/yellow wire to the blue/black wire after cutting off the connector.
The rest of the wiring is simple: black reg/rec wire to ground, red reg/rec wire to battery, remaining reg/rec wires to alternator, any-to-any.
The Bottom Line
Very little work, compared to the hassle of being DOR with a dead charging system just once! A price just a bit north of $400 buys the complete system with reg/rec, and none of the risks of Chinese quality control (is that an oxymoron?) or used components which are, like most of us, old, stiff, and waiting to fall apart. The price isn't much higher than the tab on a good full system rewind job on an OEM alternator.
With higher output, lower maintenance (no brushes), reliability and lighter weight, you get a lot of bang for the buck--and you get Michael's tech support on top of it!
The system has other advantages. The Sparx rotor keeps the rotating mass closer to the centerline of the bike, improving handling. The assembly (rotor, stator and stator mount) is also about 1.25 lbs. lighter than the OEM assembly. Here's the installation drill.
Mounting
In present form, you'll need a bit of hardware and know-how (though Bill and Michael are working on that). Remove the OEM stator, and remember that the stator wiring bundle is retained by the shift shaft guard. Loosen the engine case screws holding the guard in place and remove it to extract the wiring. Tap the stator screws loose with a hand impact driver (hammer-powered, not air-powered!), separate the stator wiring connector, and remove the stator.
To remove the rotor, either spin the nut off with air impact or put the bike in gear, screw down the rear brake adjustor until the rear wheel is locked or put a foot on the brake pedal, put a cheater bar on your breaker handle, and turn. Then remove the rotor with a proper rotor puller (not a jaw-type gear puller!) Then install the Sparx rotor on the shaft. As with most aftermarket parts, a little hand-fitting was called for on my unit, as the back of the keyway was a touch too narrow for the key. A few strokes with a file took care of it. You'll need a 1" (25 mm won't do it) socket to torque the Sparx nut down.
The stator mounting bracket comes next. It slides into the crankcase stator castings and mounts to the same holes as the OEM stator. The long OEM 6mm screws must be replaced with 25 mm length. Finish seating them with a hand impact tool.
To fasten the stator to the bracket, 3 8mmX1.25 pitchX40mm long screws are required. After installation, the air gap between rotor and stator must be checked with a feeler guage, as per the instruction sheet supplied. Mine bolted up first time with adequate clearance all the way around.
Marking
The Sparx kits come without TDC or timing marks scribed. I fabricated a template for Michael and Bill after degreeing mine in, and if keyway location etc. show to be consistent, they may send out the kits with TDC and ignition timing marks punched. For those of you who can't wait (or who realize that even the OEM marks are often out by 2* or more due to keyway cut and other manufacturing variations and want to know exactly where you are), here's the drill I used.
You'll need a TDC locator--not the "whistler" type or a hard-stop type, just a simple plunger and sleeve. Holeshot used to offer a good one but it's not in their current online listings. If what you wind up with has a spring on it, get rid of the spring. You'll also need a degree wheel; Domi Racer has a nice one, and I think you can download a printable one on Michael's Vintage Brake site which you can apply to something stiff.
Put the bike on a lift, in gear, with the rear brake adjustor run down for enough resistance that the wheel holds position when you turn it enough to remove drive train lash. This will be useful in getting the engine to cooperate in turning, damping the effects of valve spring pressure and flywheel when you want to hold position.
Remove the left side tappet covers. Using a wrench on the rotor nut, turn the engine over by hand, observing the rocker and valve action. When the exhaust valve is closed (rocker up, tappet loose) and the intake is open (rocker down, tappet tight), the left cylinder is falling on the intake stroke. When the intake rocker lifts all the way, the piston is rising on compression. This is where degree readings are taken, to avoid fouling the locator in the valves. Rotate a quarter turn, and install the TDC locator in the left sparkplug hole. Due to the angle of the plug hole, TDC locators tend to take enough sideload to lock up when the piston's rising, so keep the locator free with one hand and turn the crank CCW with the other until you find the highest point on the plunger. Choose one of the radial lines scribed on the rotor (I used the one pointing up) and paint mark it. Then make a temporary mark on the stator (I used the upper surface). This shows approximate TDC.
Next remove the indicator plunger, leaving the sleeve in place (if not removable, block it in raised position with a small hose clamp, O-ring, etc.) Remove the Sparx rotor nut. Stack enough washers on the crankshaft to install the OEM nut without running out of thread and torque to 30 ftlbs. Align the rotor mark with the temporary mark. Install the degree wheel over the nut and secure it with a second nut, installed at a firm finger tightness without allowing the crankshaft to turn. Fasten a piece of wire down with a screw in a case cover mounting hole and align it to point at the 0 mark of the degree wheel.
Install or free the indicator plunger. Reach behind the degree wheel, making sure not to contact it, with a 17 mm. wrench, and rotate the engine CCW, keeping the plunger free as you go. When the lowest piston drop you can read on the indicator is reached, look at the degree wheel and record the reading ATDC. Then pull up the plunger, rotate CW past TDC until the same drop point is reached BTDC, and record the number.
True TDC is at the midpoint. For example if ATDC drop occurs at 40* and BTDC drop at 30*, the TDC mark should be moved 5* toward ATDC, so that the measured drop will occur at 35* both before and after. Turn the crank CCW till the pointer shows 5* past the 0 mark, remove the degree wheel, and make a corrected mark. Reinstall the degree wheel as before and verify the new mark. Once you get a consistent result (it may take a little practice), set a straightedge along the rotor line and scribe a line into the stator. Then use the same procedure to locate ignition timing marks with the retard mark at 15* BTDC and advance at 40* (or wherever your best setting is--my engine favors 37*). Verify before marking and after.
Wiring
One quirk of the Sparx system is that it has no provision for a signal that's usable by the safety relay. To bypass early SR's, remove the relay, clip off the connector, and splice the red/white wires together, restoring power to the solenoid. Later SR's (2 relay domes) also turned the lights off until the alternator signal was picked up. For these, splice the red/white wires as above, and also splice the red/yellow wire to the blue/black wire after cutting off the connector.
The rest of the wiring is simple: black reg/rec wire to ground, red reg/rec wire to battery, remaining reg/rec wires to alternator, any-to-any.
The Bottom Line
Very little work, compared to the hassle of being DOR with a dead charging system just once! A price just a bit north of $400 buys the complete system with reg/rec, and none of the risks of Chinese quality control (is that an oxymoron?) or used components which are, like most of us, old, stiff, and waiting to fall apart. The price isn't much higher than the tab on a good full system rewind job on an OEM alternator.
With higher output, lower maintenance (no brushes), reliability and lighter weight, you get a lot of bang for the buck--and you get Michael's tech support on top of it!
