HARDTAILING A HARLEY SPORTSTER
Got a Harley Ironhead Sportster sitting around collecting dust? Turn that scoot into a classy chopper with a Lowbrow Customs Weld-On Hardtail Rear Section for 1952-1982 Harley-Davidson Sportsters.
In this How-To video, Tim Fiorucci of Fiorucci Fabrications walks you through the features on our USA-made hardtails. He shows just how easy it is to install onto your stock frame.
From how to measure, to cutting, putting the motor in to act as a jig, tack and finish welding, the entire is shown start-to-finish.
WATCH THE HARLEY IRONHEAD SPORTSTER HARDTAIL FRAME INSTALL VIDEO
This video will teach you the proper method to build your Sportster chopper in no time flat. So break out the hacksaw, the tool box and a welder and lets get to cutting. Why? Because choppers, thats why!
If you enjoy this video, be sure to like it and subscribe to the Lowbrow Customs YouTube channel.
If you have any questions, post them in the comments below!
STEP-BY-STEP PHOTO TUTORIAL ON INSTALLING AN IRONHEAD SPORTSTER HARDTAIL
IRONHEAD SPORTSTER HARDTAIL FRAME FEATURES & OVERVIEW
This hardtail is made right here in Cleveland, Ohio and made with the highest quality steel. 
1" tubing with slugs on the bottom frame rails.
The back bone is 1-1/2" with a hollow slug which will allow for wiring to be fed in if you wanted to run internal wiring.
On the back side of the backbone is a larger hole left as well for internal wiring if desired.
Bot the backbone and bottom rail slugs are rosette welded in and you should also rosette weld the front stock frame rail section when mating the slugs. The slugs make the joints extremely strong.
The rear motor mount plates are made up of 1/4" thick plates and make for a great flat surface for you to clean your paint off and give a great flat metal mounting surface to the motor. This prevents the motor mount bolts from ever loosening over time.
The hardtail comes with an top motor mount tab because you will be cutting passed the top motor mount on your stock frame.
Another great feature on this hardtail is it comes with a stock gas tank mount so you can run your stock Ironhead Sportster gas tank confidently, and with out having to do more fab work.
The lower motor mount on the back has two mounting holes for an integrated lower fender mount that you can mount a battery box directly too.
Two gussets on the top make the frame just extra strong and beefy and they could also allow for slots to be cut for seat forks to be slid in.
The rear axle plates have a raised stand off that will also allow for you to scratch your paint off and give a clean surface for your axle to live on.
The axle plates take 3/4" axle and you will use a stock style axle adjuster utilizing this fixed tab on the rear. This will allow the adjusters to pull back just like a stock bike.
These axle plates are mirrored and do not have mounts for a drum brake. A brake stay tab is provided separate so that depending on the disc brake you choose to run you can mount in the right location.
The hardtail kit comes with the necessary hardware to mount the rear lower motor mount to the motor because you know longer have the tomahawk style mount.
STEP 1: MEASURING
You are going to measure on your back bone from the front gas tank mount hole back 6 7/16" parallel with the backbone.
Measure from the lower front motor mount hole back 14-3/8" on each bottom rail.
If you have never done this before, try cutting a little longer, you can always cut more off but its a lot harder to step it up or fill larger gaps if you cut it too short. 
Awe feels good, right!?
After cutting, on the front section you are going to use to mate with the rear hardtail section. Drill 1/4" holes on the bottom of the backbone and on the bottom of the lower frame rails. Also use a deburing tool to take off any burs on the inside of the tubes.
STEP 3: SLIP THE HARDTAIL INTO THE STOCK FRAME SECTION
Combine the hardtail and front section of the frame, start by lining up the upper backbone first then the lower rails.
Use a rubber mallet to help mate the two together.
We are going to use the motor as a jig. Place the motor on its primary side and lay the frame over it in preparation to bolt the motor to the frame. This makes life so much easier when you don't have an extra set of hands.
Use the provided hardware to bolt the bottom motor mounts the the frame. Don't torque them down but make sure they are secure.
Pick the frame and motor upright and install the front motor mount plates with out the spacers. This will help you see if you have any large gaps and if the motor is in the right place.
It will also help determine if you need to give it a few more whacks with the dead blow or trim on the stock frame cuts.
You can also mount your stock gas tank to check the holes are aligned right. But not necessary to use the gas tank as a jig or fixture.
We had a few small gaps on the bottom rails, using a dead blow Tim gives it a few whacks to set it in the right place.
You want to have about 1/8" gap or less on each of the butted together frame joints.
This is the ideal position the bolts of the front motor mount plates should be in, the middle of the slots.
The backbone is about 1/16th to 1/8th" this gap is good for weld penetration and will secure well.
STEP 5: TACK WELD THE HARDTAIL FRAME IN POSITION
Clamp a straight edge on to the backbone to ensure its straight, then tac weld in a few spots.
Tack it up! Well, just the backbone. 
Add the spacers into the front motor mounts and securely fasten them. 
Make sure the gaps didn't change after tightening the front motor mounts and tack up the lower frame rails.
STEP 6: POSITION & WELD TOP MOTOR MOUNT BRACKET
Use the top motor mount you are going to use for this build and center the top motor mount tab supplied. We are using the Gasbox Top motor mount with key and coil mounting options.
You may have to use some washers to get the right height. Also look top bottom and side to side to make sure the tab is even after bolting it up.
Tack the top motor mount tab to the backbone.
STEP 7: FINISH WELD
Finish weld as much as you can with the motor in the frame. Once you feel you got enough done, you can remove the motor and do the hard to reach places.
NOTE: Jump around to different areas when welding. Don't finish weld the same area all at once because it could shift or move other parts that aren't yet welded.
Much easier to finish weld those hard-to-reach places with the motor out.
Don't forget to fill your drilled holes for the rosette welds.
Finish welding the top motor mount. Capping off the weld at the ends and moving it a little on the inside of the tab will add extra strength.
STEP 8: PUT THE ENGINE BACK IN THE FRAME AND KEEP BUILDING!
Put your engine back in and continue mocking up the rest of the chopper you just started! Man that looks sick!
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