How To: Mount A Solo Seat Using A Lowbrow Customs Stainless Solo Seat Hinge / Pivot

The Lowbrow Customs Solo Seat Pivot is made right here in Cleveland, Ohio. Heavy-duty stainless steel that is tumbled for a beautiful finish paired with custom-made, chrome plated mounting hardware. With weld-on and bolt-on mounting applications available, installing a solo seat on your chopper / bobber project is easier than ever before. We asked the great Austin Andrella of Austin Martin Originals to share a little of his wisdom and walk us through how he installs a solo seat while using our new Solo Seat Pivot, Weld-On Spring Mounts / Perches, and 2 inch Barrel Style Springs

Straight Edge
Measuring Tape
Grinder or Disc Sander
Magnets & Magnetic Flex Rod
1/2” & 9/16 open end wrench
Welder (Tig or Mig)
Laser eye

"Stoked on these new Lowbrow Customs Solo Seat Hinge / Pivots!" - Austin Andrella

Step 1: To start this job, you will want to make sure the rear wheel, rear fender and gas tank are installed on the frame so you can judge the clearance and alignment from front to back.

We are going to be working on this Yamaha XS650 that I have been building for a customer.

Step 2: Measure and mark you center line on the frame where the seat hinge mount will go and also the center line on the cross bar where the spring mounts will go. Use a square to check center lines are equal.

Step 3: Measure the width of the seat hinge mounting bracket. Mark three lines on a ruler as you measure, end of the left side, dead center, and the end of right side of the bracket. Line up the middle mark on your ruler representing the dead center of the mount with your mark you made on the frame. Then make two marks on the left and right ends where you visualized the seat hinge mount will go. Using a square make straight lines down to the end of frame plate. Do the same step on the cross tube but with your seat pan, measure your spring studs on the seat making a mark on the ruler at the center of the left side stud, dead center and the center of the right side stud. From your dead center line on your ruler mark the left and right side measurements on the cross tube where your spring mounts would go.

Step 4: Now it is time to grind the top & bottoms of the springs to make them to sit flush and bolt down straight with your seat mounts. You can use a grinder or a disc sander for this job. To make sure they are level, place them on a flat surface and you will see how they sit flat.

I welded a bolt to a metal piece of tubing and use a magnet to secure the seat spring in preparation to grind the ends flat safely.
Do you see the difference of the left to the right one? The right one's bottom has been grounded down to be flat and will sit better on the spring mount / perch then the one on the left.
Grind both sides of each spring to sit flat.

Step 5: The Lowbrow seat pivot comes with a bracket meant for a round back bone tube so we need to get rid of that for this bike I’m currently building. Make a straight line right at the top of the radius all the way across the bracket. Grind the arc away flat and even using a disc sander or grinder. I like to clean up all the bottom side edges of the mount to in prep for welding too.

(Note:  At the time of this install, the Lowbrow Stainless Solo Seat Hinge - Bolt On wasn’t out yet, which is why Austin ground down the coped area on the standard weld-on seat hinge. If you have a plate instead of a round back bone tube on your frame, you can now use a Bolt-On Solo Seat hinge for ease.)

Marking off what area of the mount I need to grind down using a square to keep my lines straight.
Using a disc sander, notice the sparks on the disk are far away from each other because of the arc of the mount. As I grind down the mount the lines will start to get closer together on the disk and become a solid spark line when flat.
See how the lines on the disk are almost completely together now, this means the mount is almost clear of the arc and flat
After taking a grinder to the corners, this little guy is ready to get tacked in position.

Step 6: Next you will want to put all of the hardware onto the seat for mock up.

Using a Magnetic Flex Rod can help secure the bolts that keep your springs onto the seat pan.
Line your solo seat hinge / pivot where you think it looks best on the bottom of your seat.

Step 7: Using some strong magnets place the spring mounts on the locations where you marked your measurements on the cross tube. Place the seat in place with pins in to see how the springs sit and the front hinge mount lines up with your measurements. Now you can step back and take a look at your seat from multiple angles. Although you marked your center lines for reference, nothing is perfect. You can nudge the seat to the left or right to line it up visually with the frame rails and gas tank. This is where your laser eye really comes into play and it is always a good idea to have a second pair of eyes for another opinion.

Using strong magnets and line up your spring mounts / perches to the lines you marked.
Attach the seat completely to the spring mounts / perches using the hardware that comes with it.
This is where your laser eye comes into play. Make sure from all angles of the bike that the seat, the front mount, and spring mount / perches are straight, even, and up to par with your standards.

Step 8: After all is inspected and you approve of the seat position, its time for some quick tack welds so nothing gets burn or melted. Tack each side of the seat hinge mount and the spring mounts.

Tack it up man!
Ask for assistance if you need it, and make sure they don't move!
Small tacks on each side of the seat mount / perches and the front mount.

Step 9: Disassemble the seat completely. Remove the gas tank, rear wheel and fender so you have more room to weld. Clean up your marker spots and all spots you are going to need to weld.

Remove the seat and seat springs completely from the front mount and spring mounts / perches.
Make sure to clean off all dirt, oil and marker marks where you will be welding.
Removing the tank will give you more room to move around the bike to make sure your welds are the best they can be.
The same goes with removing the rear tire and rear fender out of the way.

Step 10: Now you can start welding the seat hinge mount and spring mounts. If you are Tig welding, some of the spots can be challenging to reach. Weld as much as you can and if there are a few spots you aren’t confident in doing, you can always finish welding those spots when the bike has to be taken apart and the frame needs to get prepped for powder coating and or paint.

Now get to welding up that front mount and spring mounts / perches!
Some spots can be more difficult to reach than others. Take your time and if you don't feel confident in a spot, you can always wait to finish it later. Wait until disassembly in prep for powder coating and make your final welds with the motor out of the frame. This will give you the capability to flip the frame how you need to and make those hard spots easier.

Step 11: After everything has cooled off, attach your seat and basque in all your glory! Thats all there is to it.

*Note The small leather washers on for the spring mounts go a particular way, the smooth side goes on top.

Fuzzy side down people!
Boom! Lowbrow Customs Solo Seat Hinge / Pivot installed and ready to roll!

Words By Austin Andrella - Austin Martin Originals
Photos By: Mikey Revolt

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