Do you ride the venerable 1150RT? Would you like to have electronic cruise control like it’s younger…bigger ...(and uglier IMO
) brother…the 1200RT? Anything is possible. But like most things in life if it’s worth doing it “ain’t gonna be easy”. This farkle project is no exception to that rule. But boy oh boy is it ever worth it. And the cost is less than $300.
Recently I installed a universal electronic cruise control on my 2008 Kawasaki Concours14. The result of that project was absolutely “wunderbar”. It made long distant travel sooooo much more enjoyable. Now I could actually watch the road instead of being constantly concerned with my speed and dealing with “tax collectors” (read police).
In the wake of this success I decided to tackle same project on my 2004 R1150RT. The following is a summary of the installation process.
The cruise control is a Rostra universal electronic cruise control. I bought mine at www.Murphskits.com
. Murph sells all sorts of gadgets and farkles for motorcycles. However the Rostra is an automotive cruise that many have adapted to motorcycles much like the vacuum based Audiovox CCS 100. However the Rostra is superior in my opinion because it is not subject to engine vacuum a weakness of the Audiovox IMO. The servo of the Rostra is totally electric.
I will say at the outset installation of this system on the Concours14 is much more straight forward than the Beemer boxer. First is the throttle control. On the C14 accessing the throttle arm and attaching the Rostra cable is very much like a car and requires little modification. All throttle bodies are controlled by a common shaft/arm. That arm is readily accessible and easy to attach the rostra cable.
The RT throttle system with the bowden box (cable distribution box) requires serious surgery. If you are not comfortable with Dremel and performing such “surgery” then I wouldn’t advise doing this mod. However once you see how it’s done it’s really not a big deal.
Second is the speed sensor portion of the system. The Kawasaki has a VSS wire that is easily accessed and spliced into the Rostra harness. The Kaw’s output is a square wave (digital signal) which is directly compatible to the Rostra’s “brain”. The BMW has no VSS (vehicle speed sensor). It does have a wheel speed sensor for the ABS system. But I never could get the Rostra to sense it so I had to use a wheel speed signal generator that employs a coil and wheel mounted magnets.
With this system, due to the Bowden box design for the throttle cables I employed the use of a slack tube fabricated from 1” PVC. It is simply a container that isolates cable/chain slack from any potential snags.
There is some minor fabrication one must do to adapt the Rostra automotive cruise to your 1150RT. But once complete the reward is well worth the price of admission. I have less than $300 invested in the kit.
The first section of this document will deal with the mechanical aspect of the installation. The second section will deal with the electrical wiring.
The first hurdle to clear is mechanically installing the control module (black box) and cable. On most cars and many motorcycles one would simply attach the Rostra controller cable to the throttle arm. The throttle arm on an inline four like the Concours control ALL TBs (throttle bodies) simultaneously. However due to the fact the 1150RT is a boxer and has 2 TBs separated by the crankcase each TB is controlled independently by it’s own cable. These TB cables go into a cable distribution box (Bowden box) and are attached to a wheel. The twist grip cable is also attached to the same wheel. When you twist the grip it in turn rotates the wheel and actuates the TBs.
Pretty ingenious really but it makes the installation of a universal controller like the Rostra much more challenging.
The Bowden box is under the battery/ABS module tray. I removed the hoses and wiring for the right side of the tray to access the Bowden box. Depress the retainer clip underneath the bowden box to release then slide the box out to access it. You will need to unscrew both TB cables to get to it. I made a note of the cable position by counting threads so as not to get the carbs out of sync. When I re-installed the cables I returned the thread adjusters to the exact same position as noted.
Remove the cable wheel retainer clip and pull upward on the wheel to take it out of the bowden box. Remove all the cables from the wheel.
At this point I will tell you I recommend purchasing an additional Bowden box (cable distribution box) from BMW. I bought one before I started this project and studied it for a few days before I attempted this install. The box and wheel only cost $36 … cheap insurance.
Take the removed wheel and notice it has three (3) cable grooves. However it only utilizes 2 of them…the upper and lower. The middle groove makes an ideal place to attach the Rostra control cable. But a little surgery on the wheel must be done first.
Take a cutting wheel with your dremel or a dremel sanding disk…turn it on edge and complete the cable groove toward the aft portion of the wheel (away from the head of the twist grip cable). This will allow the cable to work freely in the bowden box like the other cables. With my modification I used a bicycle cable kit I bought at WalMart as the intermediate cable between the Bowden box and the “slack tube” which I’ll address later in this document.
Next drill a hole through the wheel adjacent to the hole of the twist throttle cable retainer. It must be large enough to allow the cable head to seat securely in the groove similar to the way the other cables are retained in the wheel.
Notice the retainer hole for the additional cable goes through the twist grip cable groove into the middle groove. DO NOT drill through to the top (TB cable groove) cable groove. Drill slightly into the wall of the top cable groove…enough to countersink the head of the intermediate cable for retention.
When finished your wheel should look something like this:
You will likely have to alter the thickness of the intermediate cable head so the twist grip cable will have ample clearance to properly seat in it’s groove. When done properly the twist grip cable will actually act as a retainer for the head of the intermediate cable to keep it secured.
Next you’ll need to take a cable adjustment nut (like that found on a bicycle brake control) and install it into the Bowden box. The one I used was 8mm thread. I drill the appropriate hole and threaded it to accept the cable nut. Be careful to line the hole up with the position of the middle groove on the wheel since this IS the groove the intermediate cable will fit into. Then thread the cable head through the hole and screw the nut into the threaded hole. Don’t forget to reattach the twist grip and TB cables!
Now re-install the cable wheel onto the pivot shaft and snap the retainer ring back onto the shaft and your mod should look something like this:
The other end of the intermediate cable serves a “slack tube”. The the Rostra needs roughly 40 mm of slack to operate properly. When you twist the throttle open the Rostra cable must slide back and needs slack to accommodate this action. You don’t want slack in exposed cables under fairings because of danger of hanging on something over time. So I built a “slack tube” to contain the needed slack in the cable. I made it out of 1 inch PVC and cut a window in it. The window serves two purposes. One is to facilitate the installation of a ball chain (to facilitate the slackened cable) the other is to allow you to physically observe cable slack and tension later on in the install for trouble shooting purposes.
For the intermediate cable (left end of tube) a 3/16 x 1/8” pipe thread compression fitting worked perfect on the intermediate (bicycle cable). The Cable from the Rostra actuator used a ¼ x ¼ pipe thread compression fitting. The compression collar will secure the cable in the tube.
I mounted the Rostra module under the triple tree. It was one of the few places with ample room. You could mount it behind the pillion where the tools go but then what would you do with your tools? The space under the triple tree clamp is dead space that you might as well use for this.
I drilled a couple holes in the frame and bolted the Rostra bracket to the frame. When mounted in the center of the space it does not bump the front forks.
Next I installed the Control Pad to the left side handle bar. I simply removed one of the screws in the control enclosure and screwed the control pad base plate to it. The base plate costs a little extra from Murph…but it well worth it for the simple fact I didn’t have to “make my own”. I already had enough fabrication to do with this install. I don’t need any more!
One note: Before you install the control pad you should “waterproof it”. Remember this system is designed for a car…not a motorcycle. The control pad Murph sells is also. However many others have sealed this pad with success by simply prying the cover off and thoroughly sealing it with clear silicone RTV. Another thing you can do is employ a “rain condom”. Simply cut the finger out of a larger surgical glove and slip it over the switch at the first sign of rain. This has worked well for me. However you can also pry the cover off the switch and seal pad with clear silicone then close it back up. The fact that the control pad of this system isn’t water proof is one of the drawbacks of this system. But the alternative is from “Oz” and cost over $1000!
Finally I installed an auxiliary wheel speed sensor. Some people have told me you could employ the ABS wheel sensor…but I never could figure it out and was forced to employ an auxiliary wheel speed signal generator. There is one made specifically for the Rostra. It’s plug and play. The only place I could figure out to mount it was the front wheel. I fabricated a bracket out of aluminum plate and mounted this plate with the generator coil to the screw hole on the low left side of the left front fork receiver.
Then I placed nickel magnets into the heads of the torx screws that secure the right brake rotor to the front wheel. Using washers I shimmed the coil to within roughly 3mm of the magnets so they’d generate a signal as the wheel spins. Be sure the polarity of the magnets is all the same. It matters not if the north or south pole is facing the pickup coil as long as they are all oriented the same way.
Oh Boy!!! Now the funs starts!
I hate electrical CRAP. Wiring looms all look alike to me…A RATS NEST! Tesla and AC/DC are rock bands…Ohm is a place I hang my hat.
Electrically speaking I AM A MORON. I freely admit it! I know just enough to be dangerous and yet somehow I wired this bitch and it worked. But not until hours….days…weeks of trial and error. Arrrrrgh!
In reality there are just a few circuits to deal with on this unit. However the Rostra comes with an install manual for your reference. You should refer to this manual frequently. Rostra also provides a tech support number. But they may frown upon adapting their unit to a motorcycle.
The wiring looms of the main module consists of these:
Orange – Enable/engage light
Light green – neutral safety or clutch switch
DK Blue – tach signal not used on the 1150 RT
DK Green – set/coast
Gray – VSS sensor (vehicle speed ) not used on the 1150 RT
Brown – ignition power
Yellow – resume/accel
Black – ground
Violet – negative side of brake switch
Red – positive (hot) side of brake
Light blue and black on separate plug _ aux wheel speed generator (you will use this for the coil/magnet assembly on the front wheel)
The control pad/switch consists of these wires:
Red, brown, DK green and Yellow. These wires plug directly into the corresponding colored wires on the main loom. In addition, depending on which switch you use, there is a gray and black wire on the control pad. Grey goes to V+12DC and black to ground. On this system all black wires go to ground. And ground is very important. If your ground is compromised or weak the Rostra WILL NOT ENGAGE. Make sure you have a clean ground with low resistance.
ORANGE enable light
I highly recommend the use of an engage light. It affords the operator the ability to troubleshoot this system. All this light does is let you know that the servo is engaged and tension is being applied to the control cable. This is very important when troubleshooting because it allows you to narrow down whether the problem is electrical or mechanical.
To wire this circuit you’ll need to mount a small 12v indicator light in the dash. I installed mine on the left side of the dash between the speedometer and the aux lamp switch. I used something like this:
Wire one side of the light to the ORANGE rostra wire and the other side to 12v+ accessory (switched power).
LIGHT GREEN - NEUTRAL OR CLUTCH SAFETY
The neutral safety (or clutch) wire will disengage the Rostra if the clutch lever is pulled. This is the secondary safety release. The primary being the brake switch circuit. To wire this simply splice the light green wire into the ground side of the 1150RT clutch switch circuit. I found mine in the small black sheath from the clutch control on the left handlebar going down to the dash. I cut a small slit in the sheath, pulled the BLACK/GREEN wire and crimped a barrel splicer to the wire splicing the Rostra’s light green to the RT’s black green wire. I recommend inserting a crimp type plug (female/male) in this wire so it can be disconnected later. This will facilitate troubleshooting and diagnostics.
DARK GREEN – set/coast
The dark green of the Rostra should be soldered directly to the dark green on the control switch.
BROWN – ignition switched power 12v+
YELLOW – resume/accel
Solder directly to YELLOW on the control switch loom
BLACK – ground
Make sure you have a good ground. This is kind of like trailer lights. You can have everything wired perfectly…but if your ground is compromised the lights will operate sporadically.
VIOLET – negative side of brake switch
RED – positive side of brake switch
Bear in mind this system was designed for a car. I am adapting it to a motorcycle. A car only has one brake control (pedal) and thus one switch. A bike as you know has two (pedal and right hand lever). We must set it up so that either control will trigger the Rostra to disengage. In order to do that we’ll employ the use of a five pin relay.
The Rostra MUST SENSE GROUND in order to ENGAGE. When it senses voltage it will disengage. The ground circuit for this leg must be a solid ground and needs to have less than 3 ohms of resistance in order for the Rostra to reliably engage. The instant the Rostra senses anything thing else it will disengage.
I installed a relay under the rear tail housing adjacent to the brake light assembly. I routed the VIOLET Rostra wire to the relay’s 30 pin. Then I wired the Yellow/Gray brake wire from the 1150RT to the relay’s 87 and 86 pin. Next I grounded both 87a and 85.
The RED wire from the Rostra merely needs 12v+. It doesn’t have to be from the hot side of the brake switch. So I wired it into a “switched” (accessory) 12v+ source.
Essentially what this does is it allows the Rostra to be triggered from either front brake lever or rear brake pedal because either will trigger the brake light. So anytime the brake light is activated the Rostra will disengage. In the “normal” position the relay allows the Rostra to sense only ground. But once the brake is applied 12v currrent switches the relay and the Rostra no longer senses ground causing the unit to disengage.
LIGHT BLUE AND BLACK – Optional signal generator
With the 1150RT there is no available VSS so I had to use an auxiliary wheel speed sensor. I purchased it from summitracing.com.
This hardware cost about $25. It installs on the front wheel and it is wired directly into the light blue/black wire on the Rostra loom. It’s a simple coil/magnet arrangement that sends a pulse everytime a magnet passes near the coil.
I couldn’t figure out how to use the supplied magnets in conjunction with the RT’s wheel. I’ve seen how others have done this and I followed suite. I bought some ¼” nickel plated neo-dym round magnets and some 1/8” round magnets. I then glued the small magnets to the center of the larger nickel plated magnets with a drop of super-glue.
The smaller magnet will fit into the head of the Torx bolts that secure the front rotor to the wheel. This prevent the ¼’ plated magnet from flying off the wheel via centrifugal force. I’ve tested this up to speeds of 100 mph and they held fine.
I fabricated an aluminum bracket to bolt the coil to then bolt the coil/bracket to the available bolt hole on the lower left front side of the front fork like so.
This photo show the magnets already in place. The blue and whit wires from the wheel speed coil connect to the light blue / black wires on the Rostra unit. I put the wires in ½” shrink wrap for a sheathing to finish out the look and protect the wires.
The clearance between the magnet face and the coil face needs to be 3mm or less for the coil to generate a signal. Secondly….this is IMPORTANT! Make sure the same pole of the magnet face outward. It makes no difference if it is north or south but they must be same. One way to determine this is by stacking all the magnets. They will orient themselves accordingly. Then mark them on one side before gluing them together..
DIP SWITCH SETTINGS
I experimented with a variety of settings for this bike and the best I came up with was this.
All switches are "OFF" except 3, 4 and 11.
The Rostra seemed to control the best with these settings for me. Your mileage may vary. The dip settings are explained briefly in the manual.
In order to put the system in diagnostic mode you must “unplug” the neutral safety or clutch safety wire. Then you turn the key to on and press resume/accel while hold the power on button. Next to the dip switches in the Rostra is a small LED. It will light up under a variety of conditions. Just read the troubleshooting guide in the Rostra manual and it will step you through it.
It took me 4 days to install this. But then again I’m pretty inept mechanically and electrically. To be fair I had to spend a lot of time figuring it out, fabricating, and modifying to make it work. I’m guessing a more skilled individual could do it in half the time or less.
I’ve tested this system from 40 to 100 mph and it works well. I’ve also tested it on flat roads and very hilly terrain as well. So far I’m pleased after 3000 miles of use.
Total cost for me was less than $300. But the convenience of riding with an electronic cruise control is priceless.