December 2005

Fitting the "Command AC60 Cruise Control"

I would like to run you though how I went about fitting a car type cruise control to my 1982 Aspencade.
First, a little background as to how I came to chose this type of cruise control.
When I looked on the web, there were very few hits from Australia. Most of the web hits talk about an "Audiovox" brand, freely available it seems in the USA and parts of Europe. I could not find one of them for sale down under, the other type mentioned is the Australian "Motor Cycle Cruise", it sounds very nice and the instructions are well worth a download and read, but I'm afraid that the 780 dollar price tag puts well out of my single income, two kids, a busy wife and a mortgage price range.

I managed to pick up what seems to be a popular Ausi band cruise control at Autobarn (a common car accessory shop), it is a "Command AC60", and it was 180 dollars. They have other models of the same brand there; the others seem to offer only mildly more interesting extra features for a lot more money. The one exception is their most expensive model which is an all electric affair. No vacuum required .I was tempted, since I have read a lot of about the potential problems with vacuum (or the lack there of), but again, the dollars drove me back.

So, what do you get for your money? Well, a basic but complete kit to fit a cruise control to a car. Really, at the end of the day, there is not a lot of difference from a Goldwing to say, a Mini.
All the bits are there; vacuum actuator, control panel, electronic brain, magnets, pickup, a wiring loom, and bags of zip ties, bolts and assorted hardware. The instructions are pretty clear and fairly well laid out, mine came with an amendment stating a few changes, but nothing drastic.

So, let's get down to it.
For no reason, I decided to start at the back wheel and move my way forward. The Audiovox that the Yanks are fitting can pick up the negative of the coil and use that for the speed sensing, but the AC60 can not do that. Apparently some of the other Command models can. In the end, for me, it did not matter as I am going to be working on a bike computer soon and wanted to have the rear wheel pulse for distance and speed for that, so the one sensor could do double duty for me.
I decided to mount a hard drive magnet on the rear wheel instead of the one supplied. They have a lot more strength and so the sensor does not have to be so close. I shaped it to fit in the grove nice and snug, some silastic held it in place.
The sensor fits nice in the "window" of the brake caliper arm, so a simple right angle bracket is all that's required to hold it there.
If you chose to use the supplied magnet, then I don't think you will have any problems as such, you will just have to be careful that you get it as close to the pick up coil as they recommend in the manual.

Moving forward to the vacuum actuator department. Those that have fitted the Audiovox claim that you need to either use 3-4 cylinders or 1 cylinder and a vacuum reservoir. Interestingly, the Australian Cruise Control mob claims that one cylinder is enough for theirs. Not wanting to make and fit a reservoir, I went the 4 cylinder path. It really is very straight forward. I did not have enough tube, and on Boxing Day very few hardware shops are open, so I have some odd sized blue tube at the moment, but will be swapping it out for some 4mm black heat proof stuff asap. A few "T" pieces and you end up with all 4 cylinders plumbed into the actuator.
While I was at it I also fitted up a vacuum economy gauge. I like knowing what my instantaneous economy is, and it's a constant visual reminder for me to back off and take my time.

The actuator itself fits nice into the left or right hand side. I don't think it really matters which side...well, it does, but only as far as how you connect the cable up.

Speaking of which, I spent a fair bit of time mulling this one over. All the web sites that mention fitting an after market cruise control state this as the most time consuming and fiddly part of the whole job. I would agree with them. You don't need to look at the situation to see why it's so tedious. There is just so little room between the front of the fuel tank and the push-pull cable throttle cable attachment. I looked and thought for a long time, and then I went for a ride. While riding on a deserted straight road I reached down and used the side arm that links the right hand two carbies to the throttle spool to set my speed, and it worked a treat. I could not hear or feel the difference between twisting the throttle or using the side arm on the right hand two carbies. So, using the choke cable bracket as the mounting point, I hooked up the actuator cable. It took about 3 minutes.
Let the record show, I had to pull apart the vacuum actuator so I could remove the center cable so I could cut the outer down to a good length, then I cut the inner after it was all mounted. You could leave it at the full length, but the extra would have to be coiled up, and thus add friction to the cable, not a good thing.
Because I went this way about the cable mounting, I decided to mount the actuator on the right hand side of the bike. I used stainless steel hose clamps; they seem to do a great job. I was thinking of using small "U" bolts, but the hose clamps might be better as you can spread them further apart on the bracket and thus get plenty of stability. The cable runs across the back of the radiator (it misses the fan by a long way), around the left hand carbies and back between the fuel tank and the air box. It's a very neat install and one of the best things is that you can clearly see it, and there is just no way that the cable is going to jam, and to top it off, you don't need to use that little goofy ball and chain linkage!

The electronics fit nicely behind the left indicator assembly. Pick up the +12v ign volts from your source of choice. I grabbed the ground off the indicator since it's nice and close. (Nov 06 update. The green wire on the indicators is NOT ground. It will work, but not the best way. Find a real ground in the faring wiring loom) The brake switch cable runs between the tank and the air box, so it's easy to get to. Even though this comes off the back brake switch, the way the bike is wired; it will also drop out the cruise control if you apply just the front brakes. (The extra blue wire in the photo is the low air pressure warning switch). (Nov 06 Update. When I changed both the rear stop/parker globes for LED's, the cruise control would not engage. For now, I have one LED and one globe, this offers enough what ever to keep the cruise control working.)

The 3 button control panel can be mounted in a variety of places. In the end I chose to make a small bracket that came off the clutch lever bolt so that it would be close to my left thumb for pressing the set button.

That's about it. Test it as per the manual. Take it out and ride long and far!
The photos will (hopefully) clear up any last questions.

Problems?

None really, when I pulled apart the vacuum actuator I was not careful putting it back together and it leaked. It was very simple to fix once I slowed down and saw how it goes together. Take your time and you should not have any problems. DO NOT be tempted to save some time and try and cut just the outer cable with the inner still there!

So, how does it go?

Really well. It's a weird feeling at first having the throttle grip move under your hand. There is no getting around this, and it only takes a few trips for you to get used to not fighting the control.
After a few trips I came to the conclusion that the actuator did not have enough pull when going up even gentle hills. I found that I was helping open the throttle to keep the speed constant.
I decided that I would make/build a vacuum reservoir and include the one way valve. This valve is the key to the reservoir; it keeps the vacuum in the tank from each stroke of each piston.
I was very pleased to see that Command offer a tank with a built in one way valve, I was also very pleased the price, only 30 dollars, at this rate I'm not sure its worth messing around making one..??
Fitting could not be simpler, vacuum into the tank with the valve, and vacuum out of the tank to the actuator. Just like the vacuum actuator, once the faring side is on, you can hardly see it.
The performance boost that came from fitting the reservoir is astounding! I would go so far as to say that you must fit a reservoir with a one way valve if you are fitting a vacuum cruise control to your bike!

The bike now holds its speed with no help from me over all the regular roads that you would expect it to. Only on very steep hills where I am considering kicking it down a gear does the speed drop off.

I have found the bike to be extremely relaxing to ride now; each hand can take a break with no over or under speed problems. For the record, I had a throttle jam type of control fitted, it still is, and I use it for very quick lock and unlock situations when I don't want to take either hand off the grips.