How to Build a Sportster
(from a pile of junk)
Chapter Six
Progress to date, Tuesday, April 25, 2006. With
the cases in the frame the rest of the build up consists of attending
to the hundreds of little tasks that make up final assembly. I
had a halfway decent set of jugs and pistons leftover from when
I built my stroker, so I honed those jugs out a little and bead
blasted the pistons. They are not quite as perfect as I'd like
them to be, there are a few light vertical scratches on the jugs
and the pistons, but I think they will work just fine. Just a note,
the jugs and heads are painted, not powder coated. There is a special
powder for high heat uses which I haven't used yet and I don't
feel like figuring it out just quite yet. I use Plasti-Kote Engine
Enamel, I've used it on a lot of engines and the stuff is incredibly
durable. See the rags jammed in around the pistons and rods? Ever
drop a piston pin spiral lock ring into a crankcase? It is a lot
easier to make sure you don't drop one in there than to try to
fish one out. The piston and jug assembly is straight forward,
lube up the piston and the jug with engine oil, remember to put
the base gasket on and drop the jug over the piston. I'm not going
to go into measuring jugs and pistons. Suffice it to say, the clearances
need to be checked. If you don't know how to do it, make sure you
have somebody you trust do it for you. I always do my own measurements.
And check the ring end gap. A little too much is better than not
enough, if a ring gets hot and expands and there is no room for
it to expand into, it will break and tear up the jug. You can tell
when that happens by the smoke and oily greasy crud blowing out
of your tail pipe.
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I did the heads a month ago, so they were ready to
bolt on as soon as the jugs were in place. There are a couple of
things to keep in mind. One of those things being the head gaskets.
Most gasket kits come with a .015" thick copper head gasket,
toss that one in the trash, do not use it. Order up a set of the
.045"
thick copper head gaskets and use those. The reason being that
the spigot, that little lip that sticks up on the jug will hit
the head before the head fully compresses the .015" thick
gasket, the engine will probably have OK compression, but, because
the copper gasket is not completely crushed, oil from the cylinder
head drain back holes will be sucked into the cylinder when the
pistons are moving down on the intake stroke. Don't believe me?
Set the head on the jug and measure the gap between the head and
the jug with a feeler gage, it will probably be about .017" or
.018". You can mill or file down the spigot or you can use
the thicker gasket. I like the thicker gasket, it's easier. I also
like copper because it transfers heat from the head to the jug
better than the fibrous gaskets. The second thing to keep in mind
is that the rocker box must be bolted to the rear head before the
head is bolted down. It is impossible to install the rocker box
after the rear head is installed. In my opinion the stock XL has
two critical maintenance faults, one is the rear head/rocker box
problem and the other is that the oil pump can't be removed with
loosening all the engine mount bolts and twisting the engine around
in the frame, if not removing the engine entirely. Let's talk about
head bolts for a minute, I happened to have a set of chrome socket
cap head bolts, don't buy those. They suck. You can get a torque
wrench on the bolts for the front head, but it is damn near impossible
to get a torque wrench on the two right side bolts for the rear
head, largely because the god damn rocker box that you have to
bolt on before you bolt the head on, is in the god damn way. If
I had a full set of stock head bolts I would have used them,
but I didn't, so I used the left over chrome socket cap bolts which
I took off of another engine because they sucked so bad. The stock
bolts are a little easier to get torqued up. So let's talk about
rocker boxes and rocker arms for a minute or two. Being oldy fashioned
your XL has four rocker arms, they are all four different from
one another, but they ain't idiot proof. The exhaust valve rocker
arm has an extra hole to dump oil on the exhaust valve. It is possible
to put a rear intake rocker arm on in place of the front exhaust
rocker arm. So pay attention to where the extra hole is and don't
screw this up. If the tip of the rocker arm that pushes the valve
open is pitted or galled you can smooth it up with a
sanding drum on a Dremel tool.
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> click here for larger image <
And that wraps up the top end. Moving on to the primary.
You may have noticed me bitch back when I began this project last
November that I was missing the entire primary drive. Well I've
been buying bits and pieces on eBay and have most all of it rounded
up. One of the things I had to do was to rivet a kickstart ratchet
plate to an electric start clutch basket. I also
ended up buying the V-Twin brand kick start parts. You get a kickstart
shaft, ratchet plate, kickstart gear, kickstart shaft gear, nut
and lock tab. All quality stuff, except for the way they drilled
and countersunk the holes for the ratchet plate. The countersinks
are way too deep, the head of the rivet is below the surface of
the ratchet plate, it is impossible to pound a rivet in a hole
like that and have it make a tight fit, there will be a gap between
the head of the rivet and the ratchet plate. Believe me, I know
rivets, being an ex-airplane mechanic I've driven thousands of
rivets. What I ended up doing was drilling and countersinking new
holes between the useless holes they so thoughtfully provided.
In order to center the ratchet plate on the basket I made an alignment
tool on my lathe to keep the plate centered while I drilled the
rivet holes. You can pound these rivets in a number of ways, a
rivet gun and bucking bar, a hammer and lump of steel, or, even
a hydraulic press, which is what I used this time, will work. In
the picture below the primary is just test fit, I found out I need
a snap ring for the bearing in the clutch hub before I can actually
tighten all the bolts up and install the clutch. I also had to
make a spacer to get the clutch hub to line up with the motor sprocket.
HD sells different length spacers, I could have bought one, but
it was just as easy for me to make my own. Check the alignment
by snugging up the motor sprocket and laying a straight edge across
it to see where it intersects with the clutch basket. Make or buy
spacers to make the two things line up. If your spacer is too long,
you can grind some off. But you have to be careful, if you grind
too much off there won't be enough clearance between the kickstart
ratchet gear and the back of the clutch basket, the two things
will hit each other when the engine is running and they will make
a bunch of very unfriendly noises. Mostly they will be saying things
like, "hey stupid, the guy on the web site said you'd fuck
this up if you ground too much off." One other note here,
the kick start shaft gear has a cam on it that retracts the ratchet
gear when the kickstart lever is up. The kickstart ratchet gear
rotates around the clutch spacer. If the bushing in the kickstart
ratchet gear is worn, the ratchet gear will sit cockeyed on the
clutch spacer when it is being retracted by the cam on the kickstart
shaft gear, this will also allow the kick start gear ratchet gear
to hit the clutch hub when the engine is running and also make
all sort of unfriendly noises, this time they will be saying things
like,
"hey stupid, the guy on the web site said to check the spacer
and the bushing for wear." I had a whole box of kick start
parts and was originally planning to go through that stuff and
pick out the best of it and use it rather than buy new parts, but
when I sat down and started matching up spacers to bushings to
gears I found out I didn't have the right combination of spacers
the correct length that weren't worn too bad to use to go with
gears that had good bushings in them. So that is when I decided
to use the V-Twin stuff. One other point to mention, the early
XL's kickstart ratchets, and I'm not sure where the change over
is, had more ratchets on them, so you cannot mix an early style
ratchet plate with a late style ratchet gear. You can convert the
early style to the later style, as a matter of fact you pretty
much have to because the early style parts are not available from
HD or aftermarket.
> click here for larger image <
> click here for larger image<
Moving over to the other side of the bike, here is
a handy dandy little tool. Just the thing you need to hold a sprocket
when it is time to tighten the big nut. Just a piece of old chain
and a piece of steel bar. Find something sturdy on the bike to
bolt the steel bar to. Be careful, if you don't find something
sturdy enough, you can break a chunk off the bike. On Sportsters
I use one of the sprocket cover mounting bolt holes. This tool
works on on big twins too, it even works on my Yamaha, basically
anything with a 530 chain. Notice the oil line routing, the line
to the rear (left) of the sprocket is the feed line to the pump,
notice the clamp above and to the left of the sprocket, that clamp
ensures the line won't be sawed in two by the chain. The feed line
is as short and as straight as possible with no elbows, I know
for fact that extra elbows or bends in the feed line can cause
cavitation in the oil pump. The lines to the right of the sprocket
are the crankcase vent line that equalizes pressure between the
crankcase and the oil tank and the return line which runs down
from the brass fitting then forward to the filter and cooler before
heading back to the tank.
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Progress to date, Sunday, April 30, 2006.
Time to put the primary together for keeps. I got the
snap ring fro the basket bearing, everything has been test fit,
tranny works good, kickstart works good and all the little bits
and pieces have been rounded up. Let's take a look at some homemade
tools that come in handy when working on the primary. At the
top is a hunk of steel channel and a couple of pieces of threaded
rod. That is the clutch spring compressor. It ain't fancy but
it works. On the lower left is a gadget used to lock the clutch
basket to the motor sprocket so you can tighten the big nut on
the motor sprocket, nothing more than some 3/16" steel strap,
some threaded rod and a couple of pieces of steel tube, also
simple and effective. And finally, two clutch disks welded together,
this locks the clutch hub to the clutch basket, so you can tighten
the big nut on the clutch hub. You guessed it simple and effective
too.
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Primary ready for assembly.
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Locking devices installed.
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Spring compressor installed.
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That was easy, wasn't it. So with the primary together
it is time to install the push rods and adjust the valves. Get
yourself a spring to hold up the push rod covers while you are
adjusting the valves, it makes it a whole bunch easier.
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Time to tend to the steaks and refill my gin. Ahh,
much better. Actually it is time to go eat the steaks... and have
another gin. It doesn't get much better than this, perfect weather,
some steaks cooking on the grill, a day spent working on a Sportster
and a gin and tonic to finish the day off. Well the sun is setting
on another glorious day, springtime in Texas is nice. Now, primary
covers and what makes me different than most guys. The primary
cover on this bike is halfway trashed, I've seen worse, but I've
also seen much better. The fact of the matter is that the average
joe would wipe the lumpy crud off of this one and have it bolted
on in about five minutes. I'll probably have 6 hours in this cover
before it is installed. First off, I sandblasted it, then spent
an hour wet sanding it to get the worst of the scratches and
pits out prior to powder coating it. Then I like to spot face all
the bolt holes so each screw has a nice flat area to seat against.
I spot faced the cam cover bolt holes too. Then I had to heli-coil
where the adjuster screws into the cover. The other thing I like
to do is to drill out the release ramp and drill and tap holes
for 8-32 countersunk screws to hold down the release ramp, do you
have to do that? No. It's just something I like to do. I would
have had it powder coated, but I ran out of black powder.
> click here for larger image <
> click here for larger image<
So where am I? The engine is pretty much done. The
valves are adjusted, the primary cover can be installed after it
is powder coated. I just bolted on an eBay carb I bought for 40
bucks, I did pull the bowl and check it it out, it looked OK,
we'll see how good it works in a few weeks. Oil system hooked up,
even has oil pressure. I have a clutch cable and lever. I have
brakes. I just drug out a set of beat up old drag pipes I plan
on using, I don't like to spend any money on an exhaust. I tend
to beat up an exhaust system pretty good, what with dragging the
pipes on the ground while cornering at 95 MPH. It just ain't worth
spending the money. This baby is getting close to fire up time.
I still have to make up my mind an ignition system, I have a coil
and three sets of points cams, I think they might all be bent a
little. I also have an electronic ignition module off my 93 that
I think will work. Let's see, I need a headlight, gas tank, ignition,
exhaust and wiring. I definitely see light at the end of the tunnel.
Progress to date, Tuesday, May 2, 2006. More
black powder came yesterday. I powdercoated the primary, top
motor mounts, brake pedal, foot peg mounts, foot pegs, kickstand,
ignition key/switch mount and some other little stuff. I spent
the day bolting things together. I did have to heat the kickstand
up red hot to straighten it out before powder coating it. I also
made the kickstand pivot pin on my lathe because I didn't have
one laying around. Pegs are on, brake pedal is on, primary is
on, kickstand is on. I guess I can take the bike down off the dolly
I've been rolling it around on. So I did. Now to sit on it for
the first time. Uh-oh. A problem. The rear shocks springs are way
too mushy, how can that be? A buddy of mine had the same problem
with some late model shocks on his old ironhead. I swapped out
his mushy springs for some stiffer springs I had laying around.
But I ain't got no more springs. Hey Jim, you owe me a set of springs.
But this is the kind of problem that you have to expect. Still,
the bike rolls on its own two wheels. A big day, definitely cause
to drink a couple of gins. This bike will be for sale. You can
buy it now, $5000.00, and I'll finish it to your specs. Check it
out.
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> click here for larger image <
As this project races??? to its inevitable conclusion,
allow me to expound on Sportsters for a bit. To me the iron XL
will always be Harley's best bike. It handled better than anything
else of similar displacement. Despite the smaller engine size the
900cc XLs would kill any big twin of its day. This is the bike
grown men feared, it would throw you over the handlebars in second
if you didn't know what you were doing while kick starting it.
But, in capable hands, this machine tore up everything put in its
way, at least through the sixties. And with a little tweaking it
still can put on a respectable show today. Fear No Evo, my 74 stroker
literally shakes the house when I start it up in the garage, it
does 70 to 120 in the blink of an eye. Men feared it for other
reasons too; did your daughter ever date a guy who rode an iron
XL? I bet you didn't like it, if she did. I've literally had people
roll up their car windows and advert gazing on the iron beast
and its rider when I've pulled up along side. How often does your
mere method of transportation strike fear into the general public?
Pretty often if you ride an unmuffled XL stroker I can assure you.
And I wouldn't have it any other way. Look at the early XLs, Harley
didn't give a damn how they looked, rough castings, raw machinery.
Yet the brake pedal followed the curve of the primary perfectly.
The tiny gas tank sits on top of the relatively huge engine like
it belongs there. Somehow the curves of the buckhorn handlebars
match the bike. Industrial design at its best. If you didn't know
a damn thing about engines you could probably figure out how an
XL worked. Nothing was hidden, the bits and pieces of the machine
were hanging out there, exposed for all to see. Even the new ones
carry that heritage. Where did it start for me? Back in high school
I used to walk down to Illinois Harley Davidson and generally irritate
everybody in there. I had no money and obviously
I wasn't about to buy a bike. One day a guy pulled up on a purple XLCH
chopper, unable to find neutral, he dropped the clutch to kill
the engine. Seemingly, the back tire spun around three times before
the engine quit. I knew then I had, and I mean had, to have one
of those. Maybe I'll build one someday. I've probably owned 20
iron XLs over the years and I loved them all. I love this one already.
Progress to date, Friday, May 5, 2006. I
needed to figure out the ignition system before moving on. I've
got a late model coil and ignition module, I don't have an extra
late model pickup. I also have three sets of old point cams laying
around. No matter which way I go, I'm going to have to buy something.
I can't use the late model electronic ignition module and coil
unless I buy a pickup. I can't use the points unless I buy another
coil because the point type coils have more resistance than the
electronic ignition coils. The electronic ignition would be trick
on this old bike, but finding somewhere to mount the module will
be a problem, there ain't much extra room an an XL. So I decided
to figure out a way to check the runout on the point cams, if I
have a good point cam, I'll go with the points, the wiring and
installation will be easier. Plus I am not sure how happy an old
engine will be running with a late model XL advance curve.
Point cam runout and why it matters. If your point
cam is bent you will not be able to adjust the point gap or set
the timing correctly. The point gap, when measured on the wide
lobe might be OK, but when measured on the narrow lobe, might be
off by several thousandths. I bolted the first old point cam to
an extra number 2 camshaft I had laying around and then chucked
it up in my lathe. Using a dial indicator I could tell that the
high spot on the wide lobe was .005" more than the high spot
on the narrow lobe. If this point cam was installed in an engine,
you could set the gap on the wide lobe to .015" but then the
gap on the narrow lobe would only be .010". You'd never get
this engine to run right. Now, to further complicate the situation,
factor in worn cam bushings. Remember back when I was installing
new cam bushings in the cam cover and commented that the new bushings
had several thousandths of an inch less clearance than the old
ones? Since the point cam is bolted to the number two camshaft
you will not be able to get a consistent point gap setting, if
the cam is swimming around in a worn bushing. This will also
make tuning the engine difficult if not impossible. The second
point cam I checked only had .001" thou different between the narrow
lobe and the wide lobe.
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So now I know I have a good point cam, I have a good
set of points and I have a point backing plate. All I need for
the ignition is a points type ignition coil. Next step is to sit
down with the catalogs and order a bunch more stuff. I decided
to get a new gas tank, I've got a couple old ones I can use, but,
I'd have to strip the paint off one and that is a pain in the ass
and I want to powder coat the tank black. Somehow baking a used
gas tank in an oven at 400 degrees for 20 minutes sounds like one
stupid idea I'll be glad to say I didn't try. A new tank is "only" $120.00
bucks. The shopping lists are getting shorter, but still, there
a bunch of parts to be had yet, coil, gas tank, petcock, front
brake lines, air cleaner.
Progress to date, Monday, May 15, 2006. A
big ol box from J&P came a couple of days ago, tune into chapter
7 to see what happens...
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