Changing the Cruise Control Set Points On 1988 to 1992 GL1500

[seniorchief]

For years I’ve been looking for a way to override the cruise control speed limitation on my 1989 Honda GL1500. According to my GPS, it will only hold 77 mph on the cruise control. I’d almost given up and resigned myself to the fact that 18 wheelers would blow by me on the interstate, and that the friends I ride with would disappear over the hill in front of me unless I grabbed the throttle and didn’t bother at all with the cruise control. Rural freeways in Idaho, Wyoming and Utah can have speed limits of 80 mph, and in some locations in Texas, up to 85 mph. While I don’t necessarily feel the need to push the limits of both bike and fate, it would be nice to be able to relax my hand on the throttle while traveling at the speed limit or maybe 3 or 4 mph above if conditions were right.

For 1993 models and newer, there has been some reported success with crossing the 4th and 5th gear input wires at the connector to the cruise control module. I tried this solution and it didn’t work for my ’89 Wing. I’ve also read reports on the internet that it hasn’t worked for other owners of 1988 through 1992 Wings either. Discussion on this issue has dwindled, maybe because there are fewer of these older bikes on the road, or because people have given up on finding a solution. For those of us still searching, there is a solution.

Many vehicles use electronic speedometers. Inaccuracies in electronic speedometers, either from the factory or as the result of modifications made to the vehicle such as wheel or tire size, drive train, etc., require that they be corrected to reflect an accurate speed reading. Correcting an electronic speedometer is accomplished by recalibrating the input signal from the vehicles speed sensor (VSS) to the speedometer. While the GL1500 has a mechanically (cable) driven speedometer, it also has a VSS located behind the speedometer in the gauge cluster. It is the output signal of this sensor that tells the cruise control unit how fast the motorcycle is traveling, and this is the signal that needs to be recalibrated.

The output of the VSS on the GL1500 is a rise and fall in voltage, between 2 and 10 volts, as the front wheel rotates. Think of it as the pulse from your heart. The faster you run, the faster your pulse. The faster the front wheel on the motorcycle turns, the faster this voltage pulse occurs. At 30 mph, the number of voltage pulses reaches the lower limit of the cruise control module and you are able to set the cruise speed. You can’t set the cruise control above 77 mph because the number of voltage pulses exceeds what the cruise control module will accept. We need to slow the voltage pulse down, so that the cruise control module thinks the motorcycle is going slower than it actually is.

After researching electronic speedometer recalibration online, I found what I was looking for; the Yellow Box Electronic Speedo Recalibrator. I chose the Yellow Box because of its size, (smaller than a matchbox) a low current draw of about 20mA, versatility, simple installation and ease of programming as well as a full 10 year warranty. It’s weatherproof, vibration proof, and heat resistant. It comes with a 6’ cable, so there’s plenty of wire to mount the unit anywhere on the motorcycle.

Yellow box is a company in Australia that has been in the speedometer recalibrating business for 19 years. At $94 the Yellow Box is very competitive with other speedometer recalibration modules on the market and the price includes airmail shipping. There are no dealers in the U.S. but you can get full information and order directly at www.yellr.com.

I initially thought that I would mount the unit in the right side fairing pocket. However, once it is programmed, there’s really no need to change it, so I decided to mount it under the seat instead

I believe that this will work for 1988 through 1992* model Wings with cruise control.
PLEASE READ THESE INSTRUCTIONS COMPLETELY BEFORE PROCEEDING

*Changes to the circuitry and wiring were made for the 1993 models. It may be possible that some of these changes made it into the 1992 models, so I’m not sure that this will work on all 1992 models. See the next section to see if there is a possibility.

As with any change or modification to any motor vehicle, you assume responsibility for any and all results.

Compatibility Check

Before you order a Yellow Box, It is important that you make sure your cruise control circuitry and wiring matches the instructions below. If it does, there’s a very good probability that this solution will work for you. Here’s how to check.

Remove the seat. Above the rear fender and along the right side frame rail, locate the 22 pin connector in the wiring harness.

Lift up on the tab and slide the protective cover with the connector inside away from and off the clip holding it to the frame rail. Remove the cover and set aside.

Locate the WHT/BLK wire in the 22 pin connector. Connect the positive lead of a voltmeter set to Vdc to the WHT/BLK wire in the connector, and the negative lead to ground. With the key on and the front wheel of the motorcycle safely supported off the ground, VERY slowly rotate the front wheel. You should see a rise and fall in voltage somewhere between 2 Vdc and 10 Vdc on the voltmeter. The faster you rotate the front wheel, the faster the voltage pulse.

Note: The voltage reading on my motorcycle had a low of just less than 1 Vdc, flashed briefly at over 8 Vdc, settled at 4.96 Vdc then repeated as I rotated the front wheel.

If this is your result, proceed.

Yellow Box installation – Preparing the motorcycle wiring

Unplug the single green wire and remove the bolt holding the antenna ground wire to the frame.

Separate the two halves of the 22 pin connector and carefully work the front connector half under and through the frame cross rail so that it’s easier to work with.

Remove 5” to 6” of the wiring harness wrapping to expose the individual wires. Locate and separate the WHT/BLK wire from the rest of the wires.

Cut the WHT/BLK wire about 4” away from the connector. This will leave enough room for you to reinstall the protective cover after the connectors for the Yellow Box have been installed.

I used Molex connectors, but a crimp style connector will work as long as you make a good connection.

Strip the ends of the WHT/BLK wires about 3/16”. Solder a male connector to the WHT/BLK wire in the wire harness coming from the VSS. Solder the female connector to the WHT/BLK wire going into the 22 pin connector leading to the cruise control module. After soldering the wire, I used needle nose pliers to make the crimp the tabs of the Molex connector onto the wire insulation.

Install the male and female plastic housings on the Molex connectors.

Using a male and a female connector here will allow you to remove the Yellow Box and reconnect the original wiring on the motorcycle.

Rewrap the wires in the harness with electrical tape leaving the ends of the WHT/BLK wires unwrapped. I used moisture sealing electrical tape.

Route the 22 pin connector back under the frame cross rail and reconnect the single green wire. Reconnect the two halves of the 22 pin connector. Reinstall the protective cover, leaving both ends of the WHT/BLK wires out of the box. Slide the protective cover back onto the clip on the frame rail to secure the wire harness. (Do not reconnect the antenna ground wire at this time.)

Preparing the Yellow Box wire harness

Determine where you want to mount your unit, measure the lengths of wire required to reach each connection, and cut the wires to length accordingly. Remember, measure twice, cut once. You could also wait to cut the wires until after you have them where you want them.

I chose to mount my Yellow Box over the rear fender. The ground (-) and the input and output connections were all within about 6” from the mounting point. I have a terminal strip under the front edge of the seat where all my accessories are connected. I used this for the positive (+) connection.

Wire colors:

RED – Positive (+)
BLK – Ground (-)
YEL – Input from VSS
GRN – Output to cruise control module

I decided I would need about 9” of wire for the black ground (-) wire, the yellow input wire from the VSS, and the green output wire that goes to the cruise control module. I cut the red positive (+) wire at 36” so I could route it along the frame rail and up to the terminal strip under the front of the seat.

With a little bit of work, I was able to slide the excess outer sheath of the wiring harness down and off the wires, saving it to use as a sheath for the red wire going along the frame rail to the terminal strip.

I used the Molex connectors for the input and output wires in the harness. Again, you can use crimp connectors here if you choose. I used crimp connectors on the red positive (+) wire and the black ground (-) wire of the harness. Make sure the terminal on the black ground (-) is big enough for the antenna ground bolt.

Solder a female connector to the yellow wire, and a male connector to the green wire of the Yellow Box harness. I used needle nose pliers to crimp the connector to the wire insulation.

Install the female and male plastic housings on the connectors.

Position the completed wiring harness over the rear fender. Run the each wire to their connection points. I ran the red positive (+) wire under the fender frame cross rail and along the left side frame rail to a terminal block under the front of the seat where all my added accessories are connected.

Connect the yellow input wire of the harness to the WHT/BLK wire of the VSS in the motorcycle wire harness. Connect the green output wire of the harness to the WHT/BLK wire going into the 22 pin connector leading to the cruise control unit.

Connect the black ground (-) wire and the antenna ground wire to the frame cross rail using the antenna ground wire bolt. Connect the red positive (+) wire to a switched (accessory) terminal so that the unit is powered only when the key is on.

Using adhesive backed Velcro, cut a piece just large enough to cover the back of the Yellow Box module. Use rubbing alcohol to clean a place on the rear fender, and secure the module in place.

Plug the 4 pin connector of the wire harness into the Yellow Box.

Reinstall the seat only AFTER you have programmed the module.

Notes on programming the Yellow Box module

Refer to the instructions included with the Yellow Box on how to program the module.

Because we are adapting the Yellow Box to recalibrate the input to the cruise control module rather than the speedometer, the formula in the instructions will be slightly different. For our purpose, the formula would be:

Correction Ratio = Actual Speed / Reduced Speed X 10000 where Actual Speed is how fast the motorcycle is really going and Reduced Speed is the desired speed signal from the VSS going to the cruise control module. In my case, the Motorcycle was traveling at 77 mph. I wanted the cruise control module to think it was only going 65 mph.

Correction Ratio = 77 / 65 = 1.1846 X 10000 = 11846

Ratio = 11850 or 118.50% (rounded to the nearest 10th)

Old Set Point / New Set point
Low – 30 mph + 18.5% =35.6 mph
High – 77 mph + 18.5% = 91.25 mph

The low set point for my cruise control on the test ride was actually 32 mph, and the high limit was 91 mph as indicated by my GPS.

I was concerned about the engine control module being affected by a change in signal to or from the cruise control module. However, the ECU controls the timing of the engine only when the motorcycle is in neutral, first or second gears, when the cruise control cannot be engaged. In third gear and above, the engine timing is controlled by the engine vacuum.

I am extremely happy with the way the Yellow Box works. I tested all the cruise control switches, including on/off, resume/accel, set/decel, each of the cancellation switches for the cruise control, and the side stand switch. I tested the CB radio, the intercom and stereo, the lights, everything I could think of. Everything on the motorcycle functions exactly as it had before the installation.

Good luck and happy cruising!

[thrasherg]

Whilst there probably aren't that many people out there with this model and wanting to make the change, I did want to offer a massive thank you for posting it and including all the pictures. It was very clear and well done.

Gary

[seniorchief]

Thanks for taking the time to read it, and for the kind words. Just wish I had found this solution years ago. Probably would have helped a lot of folks. There may be a few of the older 1500's left. I bought mine new, and like it better today than ever.

[Erdeniz Umman]

A similar method had been used for the Turn Signal Auto Cancel Unit, to extend the flashing time.

Here is the link if you want to read. You can skip the posts before #34.
http://www.goldwingfacts.com/forums/2-g ... -turn.html

[Mooseman]

Very well done and written and along with nice photos... Thank You for sharing.