Rostra Electronic Cruise control install

[Jim Van]

Well, it took a while to find a location to physically mount the control unit, but I completed the install today on the Rostra Electronic Cruise control. I wound up mounting it just behind the right hand storage compartment. To do that I had to cut out some plastic and the steel mounting strap that connected to the plastic. I then fabricated a new mounting strap that didn't interfere with the control unit.

It passed the self tests and it works on the road, but at the lower set speeds, the speed varies way too much. At 75 mph, it works pretty good, holding a fairly steady speed.

After I returned home from the road test, I read a few articles by guys who installed the unit on an older Gold Wing w/o a factory cruise and a K1200S BMW, and it looks like I have the dip switches set up wrong on mine. Looks like the gain and set up timer are both set way too high. So this week I will change the dip switch settings and see how it works after that. I'm fairly confident it should work acceptably after I do that.

It will be great to have a cruise control, especially on the interstate. The bike is so smooth, fast and quiet, that without a cruise, I need to spend too much time checking my speedometer, otherwise before I know it, I'm up to 85-90 mph. And that takes away from being able to spend time checking my mirrors and the traffic around me , etc. - dangerous !!

Hopefully, if the weather is good next weekend, I'll be able to use it during a trip to Chicago.

 

[tremarg]

Jim, I have the Rostra as well for about 4 years now. After setting up it worked well, sort of. The major problem with cruise control on a larger engine capacity bike is that the power to weight ratio is not catered for in any of the Rostra settings. After 4 years of using it, the following was happening. It was totally unreliable or better still surges below 80KPH or your your speak 50mph. Riding solo this occurred across the range, 2 up OK above 80kph. It has a lot to do with desensitizing the throttle action. When I installed the cruise control, I followed an article by Alex which was excellent ( I have the ST1300, the same issue will apply). However he placed emphasis on maintain Wide Open Throttle operation. Over time I started questioning this concept with the following change. I marked the throttle grip and over time observed the amount of travel used by the cruise control under all the operating conditions. For mine at no time was half throttle ever reached. I fabricated a "Divided by 2" lever arm and placed it between the Rostra servo and the throttle arm. This halved the sensitivity of the throttle action and also halved the throttle travel. The result, reliable operation from 50 kph/30mph to 160kph/100mph. There is no surging, especially downhill, at all even solo. It engages quicker and I cant explain why, maybe I have left less cable slack. Now done some 2,000klms and am ecstatic with the result. I have no photos as I reassembled for testing and it worked first time. On the next air cleaner changes, photos will be taken.
A couple of serious points though, be carefully that the operation of the whole throttle system is not compromised by cables bowing an hooking up on things, make sure that the hand throttle comes back ti idle cleanly and fully, make sure that moving arms etc do touch anything, a problem on the 1300, and below 80kph use the 4th or 5th gear as needed without laboring the engine. When fabricating the arm, use a precision bearing and adjustable "Arm Connectors" available from hobby shops, making certain that there is no side movements of the arm and no clearances in the connectors.
It is now perfect for me, equal to any automobile cruise controls that I have used. I am now convinced that Wide Open Throttle capability is potentially dangerous and unnecessary. Also I use cruise control as a hand relief on long runs.

Hope this helps

 

[stowner]

What are the lower speeds you are referring to? I read some folks who don't engage theirs below 50 or 55 when they get it tuned to work at the normal 55+ cruising speeds. I am working on dip switch settings myself but haven't had time to test more than two settings. I used the ppm of 3200 with 4 magnets and 4000 with 4 magnets. Both stabilized well uphill and downhill at 55+mph. Usage of the coast feature to drop 5 mph or more always seems to give a pretty good readjustment surge before stabilizing again. If I tap it down repeatedly it delelerates smoothly. Not bad for a first try....
I tried 5 magnets and things got kinda funky. I don't think the Rostra likes the non symmetrical pulse. I'll try 6 magnets next just for comparison. Not sure if 6 at 6000 ppm is exactly the same as 4 at 4000.

So far, attempting 45 mph engagement yielded quite a bit of throttle hunting before stabilizing. I could live with that and just not rely on cruise at that speed but I'm interested in the "divide by 2" lever arm.
I too will be interested in any photographs or diagrams of your design. That kind of reducer is close to what the MCCruise uses as a solution .
Matt

 

[Jim Van]

Last night, I changed the Gain Setting from Medium to Extra Low and changed the Engine/Set Up Timer from 6 Cylinders/High to 6 Cylinders/Low and PPM from 2000 to 4000 and just got back from a test ride.

The changes made a big difference in operation. No more surging at low speeds ( 45 mph ) and fairly nice and steady at 75 mph. I could live with it now like it is, but being curious, I might try changing the Gain to Low, since it could use a slightly tighter control of speed. Going up & down a slight grade, there is about a +/- 3 mph variation - slow to respond to a change of speed and it takes a while for the speed to come back up to the set point after I hit level pavement. If I was following me, that might be a bit annoying. I'm pretty happy with the results so far - worth the cost & effort.

 

[stowner]

Glad to hear it's going better !
From what I understand and other's recommendations I went with 8cylinder low and the lowest gain setting. This is a dip setting of all off except the one that defines the ppm (in your case #3 would be on and the rest off depending on the correct setting of #12; the switch type). An 8 cylinder engine has the expectation of a high power to weight ratio which is what you want. i.e. that is the least agressive setting and paired with ultra low gain should give the best results. Then it is just a matter of how the ppm setting affects the performance (and it will) I haven't found too much info on that but I am in the process of fiddling the ppm setting around and test riding.

By the way How many magnets are you using ?

In the way of a heads up, make sure the 10 amp 12 volt power supply and grounding are as robust as possible. I did see reports of Rostra trouble resolved by either.
Good luck

 

[Jim Van]

By the way How many magnets are you using ?

In the way of a heads up, make sure the 10 amp 12 volt power supply and grounding are as robust as possible. I did see reports of Rostra trouble resolved by either.
Good luck

I'm using three magnets and I calculate that's about 2,370 PPM. I'm using a setting of 4000 PPM. Engage works a little above 35 mph - just like most cars that I have driven. BTW, I'm using a home brew Hall Effect based speed sensor. It's mounted on the FD vent thingie. Have the sensor setting set to SQUARE WAVE.

For the 10 amp fuse, I'm using a separate relay being fed by a 14 AWG wire running directly from the 30 amp main fuse. Just for S&G's , I may measure the current draw in that wire ( by pulling the fuse and bridging in my ammeter ). I'll be surprised if it draws anywhere close to 10 amps. We'll see.

Changed the gain to LOW this morning and now waiting for the rain to stop to test it again. I think this may be my final setting. I might try it out on the center stand first. Like I said, I'm curious. But sometimes that gets me in trouble .......

With the initial settings, and testing on the center stand, after Engaging the RPM's rised quickly and it dropped out of ENGAGE. But the initial settings I used gave me a lot of surging. So it looked like the TACH input was working properly. Curious to see how it will work on the center stand, now.

 

[T_C]

I fabricated a "Divided by 2" lever arm and placed it between the Rostra servo and the throttle arm.

That is a good idea. If my cruise ever wanted to yank full throttle I would probably be so scared I'd be sitting on a slippery brown seat.

I made my arm the maximum length possible. I even had to shorten it just a bit because it was hitting the bottom of airbox. It seems to be working really good so far. I had a run yesterday where I det the cruise at 70, then I tapped the brakes and dropped off about 10mph from my set-speed, when I hit 'Resume' it did a nice gentle roll on and didn't get overly aggressive.

 

[T_C]

Last night, I changed the Gain Setting from Medium to Extra Low and changed the Engine/Set Up Timer from 6 Cylinders/High to 6 Cylinders/Low

Extra low and 4 cylinder low is what most of us are using.
Mine is holding at about 1mph up/down.

I'll be surprised if it draws anywhere close to 10 amps. We'll see.

It must have a bit of a surge when it uses the motor, more then I would expect through those little bitty wires they use. My voltmeter is right now connected on the same accessory circuit as the Rostra and it does take a noticeable dip when the motor engages and moves.

 

[Jim Van]

Well, it looks like I'm done with the tuning portion of the install.

Just got back from my 30 mile test loop after using a LOW GAIN setting. It's working great. Can't even tell when it engages ; super smooth Engage. No surging at the lower speed set points and the higher the set point, the better it seems to work. Only have about a +/- 1 or 2 mph variation going up & down the slight grade, now. Tapping the ACCEL results in about a 2 mph increase in speed in about 5 seconds. With an Extra Low Gain setting, it took a lot longer than that. I'm a happy camper. Works about the same as most auto cruises I have used.

As far as the throttle arm, I installed a disc w/arm to the end of the carb throttle cable disc using three 2 mm screws and nuts. The distance from the center of the carb disc to the cable "pin" from the kit that I spot welded to the disc arm is about 26 mm ( about an inch ). Rostra says the cable needs to be able to move 41mm. Since the throttle swings through 90 degrees, 41mm x 4 = 164 mm should be the circumference of a circle that the pin on the arm could swing through. Pi x ( 26 mm x 2 ) = 163.36 mm ( close enough for me ).

So to re-cap , Switches 1,3,8, and 10 are "ON" , all others OFF and when on the center stand, the RPM's rise quickly when the cruise is engaged and it drops out about a second later. Good test to check the TACH function.

 

[stowner]

Wow you both have achieved much better results than me. My performance at less than 50mph is unacceptable if there are hills involved; lots of over and under speed and over and under correcting (maybe only 3-4 mph but its annoying) at 65 mph and above mine is superb; barely know it is on and variance up and down hills is hardly there.
However, given your reports of what can be achieved I may dis-recommend the direct attachment to the bellcrank via the main cable end-drum. I will continue to try some tuning tweaks to optimize my install but I doubt I will get the low speed performance and high speed performance at the same time. I might save the linkage redesign for another time. In the meantime ......
If you have any thoughts on the tuning I would appreciate it . Here is what I've tried so far ; 3200 and 4000 on the ppm combined with 3, 4, 5, and 6 magnets. Best was 4 magnets and 4000ppm. Given your experiences, should I bump up the gain or engine settings next? Both are at their lowest setting now (assuming the engine setting is a linear setting)

 

[Jim Van]

Wow you both have achieved much better results than me. My performance at less than 50mph is unacceptable if there are hills involved; lots of over and under speed and over and under correcting (maybe only 3-4 mph but its annoying) at 65 mph and above mine is superb; barely know it is on and variance up and down hills is hardly there.
However, given your reports of what can be achieved I may dis-recommend the direct attachment to the bellcrank via the main cable end-drum. I will continue to try some tuning tweaks to optimize my install but I doubt I will get the low speed performance and high speed performance at the same time. I might save the linkage redesign for another time. In the meantime ......
If you have any thoughts on the tuning I would appreciate it . Here is what I've tried so far ; 3200 and 4000 on the ppm combined with 3, 4, 5, and 6 magnets. Best was 4 magnets and 4000ppm. Given your experiences, should I bump up the gain or engine settings next? Both are at their lowest setting now (assuming the engine setting is a linear setting)

I would try 6 Cyl / Low and Low Gain and see what difference it makes......

I think the "acid test" is how well it works at about 45 mph going up and down a not too steep hill and also how smooth the engage "action" is and how nicely it responds to pressing the ACCEL button.

BTW, I am using about an inch of beads, but have them covered by heat shrink. Less "slop" may be better, too.

Good Luck !! Keep us informed.

 

[T_C]

I am using about an inch of beads, but have them covered by heat shrink. Less "slop" may be better, too.

Are you using the 250-1223 model? Mine came with an addendum to the install manual that says to not use any chainbeads.

 

[Jim Van]

Are you using the 250-1223 model? Mine came with an addendum to the install manual that says to not use any chainbeads.

Yup - 250-1223 Universal Cruise control , but I didn't have the addendum. I bought this unit last year from some Amazon vendor, so it's hard to say when it was manufactured.

Shrinking shrink tubing over the beads basically "eliminates" the beads - they act like a straight piece of wire, now.

IMHO, it seems to me there is no magic setting up these units on motorcycles. Installations reported on the net by guys who have installed this unit on their MC all have had good results ; ST1300 , Yamaha cruiser, Older Gold Wings, BMW R bikes, etc. On a ST1100 , it's tight behind the carbs ( interference with the front of the gas tank ). I had to bend down a "tang" that sticks out from the front of the tank. But I think once installed, it's a matter tuning and making sure there is no interference problem.

One last thought - making sure there isn't too much friction in the throttle cables. The test for this may be checking that after opening the throttle fully and then releasing, the throttle snaps shut fairly quickly. I replaced both cables a few years ago when I thought they were getting a bit sticky. Maybe just taking them off and cleaning and re-lubing would have been good enough. Sticky cables would definitely cause a problem setting up the cruise.

 

[Jim Van]

I'm leaving for Chicago today for the IBA Meatlovers RTE and returning after during the wee hours of Sunday am. I'll report on how the cruise worked Sunday afternoon.

 

[Jim Van]

I'm leaving for Chicago today for the IBA Meatlovers RTE and returning after during the wee hours of Sunday am. I'll report on how the cruise worked Sunday afternoon.

I can report the cruise worked flawlessly during the 7 hour / 460 mile ride to and back from Chicago. The old ST1100 is almost a joy to ride now since I installed the Rostra cruise, XM Sirius radio and a MP3 player. Out of about 60 bikes, I had the only ST1100 at the ride, BTW. There was about three ST1300's present, also. And about six BMW K1600's . Must be nice !!

I was getting ready to tell an '08 FJR owner about my Rostra install, but he beat me to it. He had just finished installing one on his bike just last week, too !! He said a bunch of guys on the FJR Forum have installed them. Didn't get the particulars on his dip switch settings, but he used the ABS pulses ( divided down ) for his PPM signal.

 

[stowner]

I would try 6 Cyl / Low and Low Gain and see what difference it makes......

I think the "acid test" is how well it works at about 45 mph going up and down a not too steep hill and also how smooth the engage "action" is and how nicely it responds to pressing the ACCEL button.

Good Luck !! Keep us informed.

Well, the rain continues here so test riding is still a bit limited. The last place you want to test cruise control is on wet roads. I tried varying the settings from my original 8cylinder/low and extra low gain. Test riding after each change I tried 6cylinder/low and low gain settings individually and together. Of those 4 combinations the original was the best: 8cylinder/low and extra low gain; both at freeway speeds and at 45mph. I still think I will add a lever arm to the throttle bellcrank the next time I have the carbs off, but for now, freeway performance is excellent and 45mph performance is acceptable. Direct connect to the bellcrank is viable; just a little more aggressive as one would expect.

As for the spontaneous shutoff of cruise, I used the ohmmeter and found a male/female spade connector on the brake ground that I could wiggle and get the ground to disappear. Replaced it and so-far so-good.

 

[Jim Van]

Well, the rain continues here so test riding is still a bit limited. The last place you want to test cruise control is on wet roads. I tried varying the settings from my original 8cylinder/low and extra low gain. Test riding after each change I tried 6cylinder/low and low gain settings individually and together. Of those 4 combinations the original was the best: 8cylinder/low and extra low gain; both at freeway speeds and at 45mph. I still think I will add a lever arm to the throttle bellcrank the next time I have the carbs off, but for now, freeway performance is excellent and 45mph performance is acceptable. Direct connect to the bellcrank is viable; just a little more aggressive as one would expect.

As for the spontaneous shutoff of cruise, I used the ohmmeter and found a male/female spade connector on the brake ground that I could wiggle and get the ground to disappear. Replaced it and so-far so-good.

So how much friction do you have in your throttle cables ??

 

[stowner]

So how much friction do you have in your throttle cables ??

Basically none. The Rostra cable has a very gentle curve and was never kinked. The OEM cables were lubed with a slick50 all-purpose lube and a cable lube tool. Everything slicker than snot ! Curious; Why do you ask ?

 

[Jim Van]

Basically none. The Rostra cable has a very gentle curve and was never kinked. The OEM cables were lubed with a slick50 all-purpose lube and a cable lube tool. Everything slicker than snot ! Curious; Why do you ask ?

Because I think too much friction in the throttle cables will make the final results less than ideal and set-up a PITA. BTW, I have the Rostra cable forming about a 8 inch circle and it's almost as free compared to being completely straightened. I was a happy camper when I checked that !

 

[T_C]

You guys got me curious... the other day I set my cruise to 40 when I was on some hills.

It wasn't a smooth ride, slow speed up.. slow slow down... slow speed up... slow slow down...

Now how to fix it?
Quit riding at 40 mph.

Smmoth as can be at 55 or 70 or 80...

Hmmm... is it worth removing tupperware to play with settings that may or may not smooth it out at speeds that I don't normally use the cruise.