Category: Motorcycles

Now that we have the primary drive components out of the way we can proceed with the removal of the inner primary housing. But before we can remove the inner housing we need to get some stuff out of the way.

First I disconnected the wires from the solenoid and got reminded that I had forgotten to disconnect and remove the battery. (dumbass!) So always start by disconnecting the battery! (I did disconnect the spark plug wires though 🙂 )

After disconnecting and removing the battery (we need it out of the way anyway to get better clearance when we need to remove the starter motor later on) I removed the solenoid from the primary housing. To get the starter gear lever and the starter shaft out, we need to unscrew the pivot bolt, that holds the the starter gear lever, from the top of the housing. This bolt can be quite tight and there is almost no room because of the oil tank….so if you hadn’t guessed by now…..time to drain the oil tank and remove it from the frame!

After draining the oil from the tank, I disconnected the oil feed and return lines, removed the nuts from the mounting studs and lifted the oil tank out of the frame. (inspect the mounting stud rubbers and order new ones if needed!)

With the oil tank out of the way I could remove the pivot bolt and take out the gear lever and starter shaft assembly.

The front inner mounting bolts for the primary are secured with a safety wire, after removing the steel wire, I removed the upper and lower bolt (the center bolt doesn’t go into the crankcase), then removed the 2 rear bolts and the front 2 allen head bolts on the outside of the housing. (which were metric bolts in my case, so I first had to get a set of metric allen keys :S)

But wait…I’m forgetting something…. The starter motor is still bolted to the back of the primary 🙂

After disconnecting the wires from the starter motor, (label them! Especially if all your wires are the same shade of black, like mine :S) removed the chrome bracket from the back of the starter motor on the right side of the bike. Now it was time to unscrew the 2 studs/bolts that run through the starter motor and into the starter shaft housing on the back of the primary. (carefully lift it out as a unit, make sure you don’t pull the starter motor apart!)

Now I was finally able to get the primary out of the way and get on with removal of the gearbox 🙂

As you can see from the picture I try to make a habit out of screwing the bolts back where they came from. This can save you a lot of trouble with the reassembly!

More to come in Part #3!

Until recently my 1982 Shovelhead didn’t leak a drop of oil. One of the main issues with these bikes (in regards to marking it’s territory) is a leaking primary, but mine was sealed great with the help of James Gaskets and some blue silicon. Another source for oil leakage is the oil seal on the mainshaft of the transmission. In my case this turned out to be the cause of my Shovel marking it’s territory. It started with a small drop every now and then but it got worse rather quick.

It can be difficult to pinpoint the exact source of the leakage, because the bottom of the engine, primary and tranny is often covered in lot’s of grease and dirt. So I started by cleaning the bottom of the engine and transmission with some brakecleaner, and the next morning I could clearly see the oil trail leading from behind the transmission sprocket to the bottom mounting bolts. Time to take it apart!

Before you can get the transmission out you need to get some stuff out of the way, the most obvious being the primary drive. After I drained the oil from the primary, I removed the primary cover and ran into the first challenge: the clutch.

A few years ago I replaced my clutch with a Barnett Scorpion clutch (no more slipping!), but to get the clutch hub of the mainshaft I needed two specific tools from Barnett, a Scorpion Clutch Lock Plate and a Scorpion Clutch Hub Puller.

First thing was to get the clutch hub nut loose (left hand thread! so turn clockwise to loosen!). Before you can unscrew this nut you’ll need to lock both the primary and the clutch. I used a piece of steel bar and rounded both ends using a file, stuck this between the crankshaft sprocket and the clutch shell to prevent the primary from spinning. I then used the clutch locking plate to lock the inner clutch hub to the clutch outer shell. (if you have some old clutch plates lying around you could weld 2 together to make your own locking plate)

The clutch hub nut can be very tight, so I heated it up first using a paint stripper and then, using a 1 1/8″ socket and a long steel rod over the wrench, I removed the nut. (I guess you could use an impact wrench too) Because the mainshaft is tapered, the clutch hub will be very tight, that’s why you need the puller. Be sure you screw the clutch nut back on the mainshaft for 5 or 6 turns and put a washer over the nut before you attach the puller. If you don’t, the puller center bolt will push against your clutch pushrod and you’ll brake shit. (trust me!)

Before you can remove the primary drive as a whole, you’ll need to remove the compensating sprocket from the crankshaft. This is normal right-hand thread and it takes a 1 1/2″ socket. I know some people use an impact wrench to remove the compensating sprocket, but I would personally recommend against that because there’s a risk of breaking loose the magnets on the rotor, and then you’ll have a whole new problem (especially if it goes unnoticed). Finally, loosen the primary chain tensioner and you can take out the complete primary drive.

More in part #2!