Posted on Tuesday, July 20, 2004 - 07:54 pm:
I have successfully installed an all-electronic cruise control on my 2004 FJR1300 ABS. I was intending to make a nice write up, but the roll of (silver-halide) film I shot during the install was no good...I haven't used my ring light in a while and I screwed up. So let me just make a few comments, and if there are details I have left out of interest, ping me.
I used the Rostra Precision Controls "GlobalCruise" unit, part 250-1223. See www.rostra.com. I got a very good price at Brandon Distributing (www.brandondist.com), but it is still probably more costly than the Audiovox all-electronic unit. Jumping to the end: it works quite well, with a slight surging at set, but then, after about 10 seconds of a few slow accel/decell cycles (to fine calibrate I would guess), it settles right down and is very smooth. And I live in a hilly area. I would guess it is not quite as silky smooth as the vacuum unit, judging from the raves written on this site. But it is just fine for me.
The unit is not small (although it is claimed to be the smallest all-electronic unit for sale by their tech people): about 3 x 4 x 5 inches, with a rigid cable coming from the side (picture and installation manual on the Rostra web site). I did manage to test fit the unit under the seat, by just placing it into the tool tray. It fits there tightly, with some modest force, but the cable would be able to wrap under the tank and around to reach the throttle area. So, this seems do-able. But this is not where I put it...I did not swim into uncharted waters to simply wimp out and loose my precious tool tray.
By the way, besides being all electronic (a must, as I am an electrical engineer) and very well built (my judgement), the cruise cable also has a clever scheme to take up lost motion, i.e., twist the throttle and the cruise cable disappears into its sheath. No metal "beads" required to create slack. Now, back to the story:
I installed my unit between in the headlights, under the front fairing. The really nice aspect is: a straight shot gets you to the throttle area, so the cable routing is trivial. The bad news: this area is not big enough to mount the unit as supplied, and of course, the front fairing must be removed to do the install. My solution: I cut the Rostra unit into halves! The upper part is where the electronics live; the bottom is where the servo motor and cable pull mechanism resides. Thus, I created two smaller units. The servo guy is between the headlamps, mounted to a bracket that keep it rigidly in place independent of the fairing. The electronics piece sits behind and above one headlight, kept in place by wire ties. Note I have left many important details out here, but ultimately, with the help of Rostra support (they were very patient), I found all necessary connections between the two parts I created and it all functions just fine. A side feature: I can adjust the unit's "switches" through the access hole in the front fairing beneath the windshield. Also, the unit is far from sources of ignition noise and should be out of the weather, too (I have yet to ride with this set in the rain, as I am unhappy with their el-cheapo switchgear...this will change).
Besides the challenging physical install (which I claim you can avoid by sacrificing about 70% of your tool tray), I was very worried about the unit surging on the FJR. To address this concern as aggressively as possible, I deviated from the "usual" manner of attaching the cable to the throttle mechanism. To summarize, I wanted to use as much of the cable motion as possible, which is far more motion available than is created by a full twist of the throttle. So, I attached a radial arm to the throttle pulley's side (super strength, high temperature epoxy), and then attached the cable to the arm's end. After careful calibration, the system has worked well for me. But note: I never tried a "stock" install of the cable to the throttle pulley, and so, can't judge the intrinsic surging this unit might have on the FJR.
Two last details: the VSS signal on the FJR *is* too fast for this unit's switch setting (about 80000 pulses per mile). No problem: I constructed a simple electrical circuit to perform a divide-by-four function, slowing the VSS signal by 4x to 20000 ppm and also creating a very nice square wave for the Rostra to consume in the process. And secondly, the FJR has an electrical switch mounted with the clutch: why not use it? I did so, and used the Rostra's "neutral safety switch" feature with the clutch circuit (and a simple level shifter circuit) to create one more way to disable the unit...by pulling the clutch. Works fine, and is safer in my opinion than waiting for rpms to build to accomplish the same thing. By using this circuit, the cruise will not set with the sidestand down, either. (This makes bench testing harder, but I thrive on problems like this.) I did not connect the "usual" rpm sensor circuit.
I have not put too many miles on the system, but hope to change that in the Fall. This note is intended to represent a proof of concept, with some alternative install ideas thrown in, relevent (I hope) to the preceding messages.
...damocles