If you've read our first look / review of the B-G Racing String Alignment Kit, you'll know that it comes with some of the most confusing instruction manuals we have ever seen at StudioVRM.
So to help out first-time buyers and users, we've written step-by-step guide on how to assemble the kit, get it set up, and how to do your first 4-wheel alignment with this kit. Here they are:
You Will Need
- A B-G Racing String Alignment Kit
- A metal straightedge, at least 12 inches or 30cm long, where the markings start at the edge of the ruler
- A small bubble line level to attach to the straightedge to make sure you are holding it in a consistent way
- A bit of double-sided tape to keep the level from sliding off the straightedge
How to Assemble Your Kit
N.B.: Print out page 2 of the official B-G Racing User Manual. The letter codes used below are the same as what B-G uses in the official manual.
- Take the short square bars (E), small rectangular junctions (K), plastic end caps (N) and set them aside for now.
- Grab the four 3-way junctions (I) and lay them out so the yellow and black B-G Racing labels are facing. Make sure that all of the labels are right side up. Pair them up so that the wheel-shaped knobs face away from each other.
- Grab one pair of the junctions and insert one of the long bars (C) through the horizontal channel with the labels. Take care to ensure that the metal shims do not fall out while inserting the bar. If they do, put them back in so that they are on the same side as the oval shaped knobs. Space the junctions so they are roughly the same distance from the ends of the bar. Tighten the oval shaped knobs to hold the horizontal bar in place.
- Insert two of the long square bars (C) through the 3-way junction so they are perpendicular to the yellow and black labels. Make sure that the holes on the ends of the tube are facing outwards. Position them so they are roughly the same length on both sides and tighten the knobs on the junction to hold them in place.
- Insert two of the medium length bars (D) through the remaining channel in the junction. This time, make sure that the holes on these tubes are facing the same direction (to your left). Position them so they are roughly the same length on both sides and tighten the knobs on the junction to hold them in place.
- Stand the rack up so the labels are right side up. This is how you will hold it when you install it on your car.
- Grab four of the soft foam bumpers (J). Slip two of them over the two vertical bars (C) from underneath the horizontal bar, and put the other two over the two bars (D) coming out of the back of the rack.
- Install hook (G) onto the bottom of one of the vertical bars, using the provided allen key (P) and allen screws (M). Make sure the hook points towards you during this step.
- Install the alignment bar holder (F) onto the bottom of the other vertical bar, using the provided allen key (P) and allen screws (M). Make sure that the tube holder and adjuster knob are facing you.
- Install two of the double-sided chassis hooks (H) on the two bars coming out of the back of the rack. Make sure that the hooks are pointed downward.
- Grab two of the longer round bars (A), one of the round center sections (B), and two brown washers (O). Screw the longer round bars into the center section, with one washer in between each of the bars.
- Insert the assembled alignment bar into the holder (F) so that it sits roughly in the middle of the rack.
- Open the hood or trunk of your car, loosen the oval knobs on the horizontal part of the junctions, and slide them so that the rack hangs securely from your radiator support or trunk lip. Adjust the length of the medium length bars with the hooks (H) so that the vertical bars are perpendicular to the ground.
If necessary, adjust the large round knobs to adjust the angle of the rack to get the vertical bars perpendicular to the ground. If necessary, adjust the vertical bars so that the round alignment bar is the same height as the centers of your wheels.
- If any of the bars are so long that they get in the way, you may replace them with the next shortest bar from the kit (replace C with D, D with E as appropriate). If any of the bars are too short, use the small junctions (K) to attach additional lengths of square tubing (E).
- Once you are happy with the length and positioning of the bars, tighten down all of the adjustment knobs. Install plastic end caps (N) onto the ends of the square bars. Repeat the instructions above to assemble the other rack.
How to Set Up Your Alignment Rack
- Park your car on a flat, level surface with the steering wheel set straight ahead. Engage your parking brake and put the car into gear (or in Park). Set all four tyres to the same pressure. Torque all lugnuts to the recommended torque value for your wheels.
- Open your hood and trunk. Attach the racks to your car and adjust the pads so that the metal rack does not come in contact with the bodywork of your car.
- Hook the round loop on the end of the yellow string reel to the outermost groove of the round alignment bar. Lift the lever on the back of the spool to unlock the reel and walk it to the alignment rack on the other end of the car.
- Wrap the string around the other alignment bar twice, and lock the handle back into place.
- Adjust the height of the two vertical bars so that the string is the same height as the centers of your wheels.
- Get your straightedge and measure the distance between your string and the center of your wheel. You want this distance to be between 2 and 4 inches (50mm - 100mm). Move the string to a different groove if the string is sitting too far away from the wheels.
- Loosen the adjustment knob holding the round alignment bars in place. Use your straightedge to measure the distance between the center of your front left wheel and the string. Compare it to the distance between the center of your front right wheel and the string.
- Move the front alignment bar left or right until the string is the exact same distance away from the left and right front wheels.
- Repeat steps 7 and 8 for the rear alignment bar. Note that the wheel center to string measurements may not be exactly the same for the front and rear axles. This is normal, since most production cars have a different track width across the front and rear wheels.
- Re-check the distance between the wheel center and the string in the front. Adjust the front alignment bar again if necessary. If you make any adjustments, re-check the rear as well.
- Once all four measurements are the same, carefully tighten down the knobs for the round alignment bars.
- Your alignment rack is ready to use.
How to Measure Toe using a String Alignment Kit
- Go to any one of your wheels with your straightedge. If you have a small bubble level, attach it to your straightedge with double-sided tape.
- Measure the distance between the wheel rim and the string on the rearmost part of the wheel. Hold the straightedge just below the height of the string, and keep the straightedge as level as possible (this is where the bubble level helps). Write this number down.
- Measure the distance between the wheel and the string at the front. Write this number down.
- Subtract the number in step 3 from the number in step 2. This is your toe measurement. If the number is greater than 0, you have toe in on that wheel. If the number is less than 0, you have toe out on that wheel.
- You can convert your measurement to degrees by using the following formula in a scientific calculator. Remember to convert all measurements to Metric or Imperial, and to set your calculator to degrees (instead of radian):
[Toe in degrees] = Arctan( [Toe measurement in mm or inches] / [Diameter of wheel in mm or inches])
For example, if you get 1mm toe-in on a 17" wheel, the calculation would be:
Arctan(1 mm / 431.8 mm) = 0.133 degrees Toe in
FYI - I recommend using an online arctangent calculator like this.
Additional Tips and Tricks
- If you have a low-slung sports car, try using the medium-length bars (D) for the vertical sections instead of the long bars (C).
- On cars with retractable headlights or trunks that are set into the bodywork, use the long bars (C) when hooking the racks onto the chassis.
- Always adjust the soft foam bumpers (J) before resting the rack on the car. The corners of the square tubing WILL scratch your car's paint if you let them touch.
- Adjust ride height, corner weights, caster, and camber before attempting to do a 4-wheel toe alignment.
- Don't worry too much about getting the spacing of the 3-way junctions perfect. What matters is the distance between the strings and your car.
Have any questions? Feel free to ask away using our contact form. We do a lot of alignments here at StudioVRM so we are pretty familiar with common issues.