’85 - ’89 5-speed Big Twins can be converted from a tapered transmission mainshaft to a splined transmission mainshaft by using a 1990 mainshaft and pushrod. Use 1990 shaft only - the 1991 and later shaft has a smaller diameter through 5th gear. Our 039001 clutch will then fit this application.

Sportsman Superclutches will fit other manufacturer’s belt drives designed to use the corresponding stock HD clutch. On Karata drives with a cover over the clutch on the rear pulley - the cover on a 4” Karata pulley will clear the Sportsman Superclutch, the cover on a 3” Karata pulley will not clear the sportsman clutch. The Kevlar plates run well dry.

5-speed in 4-speed Big Twin conversions - use ‘79 mainshaft to align clutch and engine sprocket shaft correctly. Later shafts move the clutch farther outboard and prevent proper alignment. When using the ‘79 mainshaft and pushrod, select the clutch as though the transmission were still the original 4-speed. There currently is no splined mainshaft for the 5-speed which will locate the clutch in the proper location for the 4 to 5-speed conversion.

’84 - ’90 Evolution 4-speed Sportsters with charging system on the clutch - we have no clutch available at this time to use the HD alternator - see section 21.

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SPRING SELECTION
A. All Big Twin chain and belt drive Superclutches, Big Twin Sportsman Superclutches, Sportster belt drives, and Sportster chain drives with lockups

There are 4 springs available for these clutches. In order from lightest to heaviest they are short gold PN154406 (light), long gold PN154401 (standard), Red PN154402 (medium), and Gray PN154403 (Heavy Duty). We recommend the Short gold springs for engines below 75 horsepower where the rider needs the very lightest lever pull possible. We recommend the long gold springs for engines up to about 90 HP, the red springs for up to 120 HP and the gray springs for engines over 120 HP. These are “safe” recommendations - you may be able to use less pressure with good results. Spring pressure requirements are altered by the riding style of the rider. A motorcycle which is shifted at wide open throttle will require more spring pressure than an identical motorcycle which has the throttle rolled closed during shifts. If a spring choice is not specified, Sportsman Superclutches and standard Superclutches not equipped with a lockup are shipped with gray and long gold springs.

The spring pressure can be adjusted by turning the spring retaining nut to place the spring retaining collar below the surface of the pressure plate to shorten the springs’ compressed length. When the collar is flush with the pressure plate the spring’s compressed length is 1.250. The collar can be run as far down as .250 below the pressure plate. This will make the spring’s compressed length 1.000. 1.000 is the minimum length recommended for all springs to avoid the possibility of coil bind. When adjusting the springs, make sure that all 6 collars are set at the same distance below the pressure plate (±.010) so that the pressure plate is not pulled out of true by unequal spring pressure when released. If the pressure plate does not run true, the clutch will not release cleanly. If the pressure plate runs out .020”, this shortens the effective release travel by .010”. We recommend using a dial caliper to measure the preload depth. If you cannot use a dial caliper to measure the preload, each full turn of the spring retaining nut compresses the spring .036”, and 7 turns equals .250”. Applying more pressure than necessary will not affect the operation of the clutch, but will make the lever effort higher than necessary. The chart below shows the pressure produced by 6 springs. Heavier springs also have a higher spring rate, so a gray spring set at 300 lbs will feel stiffer to the rider than a red spring set at 300 lbs. The exceptions to this are the 2 types of gold springs - the short and long gold springs have the same spring rate.

Springs	Light PN154406(short gold)(1.75")	Standard PN154401(long gold)(1.875")	Medium PN154402(red)	Heavy Duty PN154403(gray)
Minimum Pressure (lbs)	144	210	258	276
Maximum Pressure (lbs)	240	300	372	507

Clutches equipped with a lockup unit must be equipped with lighter springs than the same application without a lockup in order to take advantage of the adjustable lockup. When installing a lockup, we recommend starting with red springs set at 1.250 installed height and adjusting spring pressure higher or lower from there as the bike and conditions demand. Lighter static spring pressure will allow the bike to leave the line without spinning the tire, and must be compensated for by more counterweight on the arms to keep the clutch from slipping in high gear.

B. 077101 Sportster clutches

This clutch uses the same spring choices as above, but has spring cups .125“ shorter than the clutches listed above. When the spring collars are set flush with the pressure plate, the installed height of the spring is 1.125” and the collar can be set to a maximum of .125” below flush without encountering coil bind.

C. 079001, 079003, & 079005 Sportster clutches

Because of the space limitations of the 5-speed Sportster, these clutches use a very short very stiff spring with a limited amount of adjustment. Because of this the clutch is available with 3, 4 or 6 springs to suit the intended application. The 079001 uses 3 springs, the 079003 uses 4 springs and the 079005 uses 6 springs. The maximum installed height of the springs allowed by the cups and collars is .660”. The minimum installed height of the green springs which will allow for adequate pressure plate travel (.070) without coil bind is .570”. An installed height of .660” is achieved when the steel collar is .210” below the pressure plate and .570” when the collar is .300” below the pressure plate. The blue springs coil bind at any installed height less than .660”, so they are not adjustable.

Spring	Pressure @.660 ht	Pressure @.630 ht	Pressure @.600 ht	Pressure @.570 ht
3 Short Green PN 154411	285 lbs	315 lbs	345 lbs	375 lbs
3 Short Blue PN 154412	510 lbs	coil bind	coil bind	coil bind
4 Green PN 154411	380 lbs	420 lbs	460 lbs	500 lbs
2 Short Blue @ .660 & 2 Short Green @ >>>	530 lbs	550 lbs	570 lbs	590 lbs
4 Short Blue PN 154412	680 lbs	coil bind	coil bind	coil bind
6 Short Green PN 154411	570 lbs	630 lbs	690 lbs	750 lbs
6 Short Blue PN 154412 NOT RECOMMENDED	1020 lbs	coil bind	coil bind	coil bind

The chart illustrates what spring pressure can be achieved in the 3 clutches. We recommend the 079001 / 079002 3 spring clutch when you must have low spring pressure for a light lever pull on a mid-range output motor. The 079003 / 079004 4 spring clutch is the most versatile clutch for a large motor because of the relatively wide range of adjustment available, and is our first recommendation for hot-rod Sportsters. The 6 spring 079005 / 079006 was first built for a nitro fueled Bonneville streamliner where power was at a maximum and space was at a minimum and the clutch was operated by a compressed air cylinder. We do not recommend PN079005 / 079006 6 spring clutch for gasoline fueled motorcycles. Over 500 lbs spring pressure may cause failure in the stock release mechanism or cable.

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SPRING PRESSURES

For all Big Twin, Belt Drives and Sportsters except 79001-79006 clutches.

		Spring Color		Blue	Grey	Red	1.875" Gold	1.750" Gold
Spring Cup Depth
	Height		Lbs.
	Collar	Spring
1.375"	Flush	1.250"	ea	79	44	43	35	25
			x6	474	264	258	210	150
	-.050"	1.200"	ea	95	52	46	38	29
			x6	570	312	276	228	174
	-.100"	1.150"	ea	111	60	50	41	32
			x6	666	360	300	246	192
	-.150"	1.100"	ea	127	68	54	44	35
			x6	762	408	324	264	210
	-.200"	1.050"	ea	143	76	58	47	38
			x6	858	456	348	282	228
	-.250"	1.000"	ea	159	84	62	50	41
			x6	954	504	372	300	246
1.250" (77101)	Flush	1.125"	ea	119	64	52	42
			x6	714	384	312	252
	-.050"	1.075"	ea	135	72	56	46
			x6	810	432	336	276
	-.100"	1.025"	ea	151	80	60	49
			x6	906	480	360	294
	-.125"	1.000"	ea	159	84	62	50
			x6	954	504	372	300

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