How to calculate VSS ppm?

Hey all,

I have a 2013 8v, and I am attempting to install the Rostra Electronic Cruise Control #250-1223. One of the settings it requires in order to operate properly is the pulses per mile from the VSS.

Anyone done this before, or at least have a method of calculating the output of this sensor?

Tim

Yes, I installed the same unit on my GRiSO five years ago, and it still works perfectly. I described the installation process in exquisite detail, here:

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Enjoy it!

Moto

My god Moto, that's a hell of a write up thanks for that! Gonna check it out tonight when I get home, looking forward to getting this thing set up and dialed in.

Tim

Hey Tim, make sure to report how it turns out. Though that long posting of mine has been read 7500 times (!), I've never heard of anybody else installing a Rostra on a GRiSO, and would like to know if it happens.

Moto

Yeah haven't seen or heard of any other GRiSO's with the Rostra. I got it installed last week, just haven't had a chance to test it or fine tune the settings/throttle cable slack. And here i was thinking I was the only one who had done this so far haha!

There is not much room to hide things like this on our bikes. That servo motor is larger than the pictures make it out to be. I ended up mounting it behind my seat on the luggage rack with my cargo bag sitting on top of it lol (hides it real well ) Its a great temporary location until I get around to modifying the rack with a more secure housing for the servo and re-position the cargo bag up a bit.

Got a couple pics here of what i'd consider the "hardest" part of the install, which is picking a location for the Rostra actuator cable to interface with our throttle bodies. Well, not the hardest, but I spent the most time coming up with this location. None of it was really hard, just fairly time consuming if you are picky about wire paths and soldering/heatshrinking your connections (which i am).


Made a 5/16" hole in the left side gusset of the upper trans mount. This will secure the little bracket I made to hold the Rostra actuator cable. It fits nicely just under the air box:
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Slightly closer shot of the bolt going through the factory gusset. The black cable inside the split-loom is the Rostra cable:
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Top down view of the bolt in the gusset with a rubber washer to hold it in place since it faces up (left side of the photo is the front of the bike):
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Right side throttle body with a small extention I added to the tb linkage. This helped make the CC perform more smoothly. Definately not much room down here:
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Made a small bracket to hold the controller and keep it near my left hand for easy access. Going to make a new bracket for it later this week and put it back towards the mirror mount and make more clearance for toggling the factory trip meter switch. This bracket worked just fine for my test ride though:
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Went on a test ride with a buddy earlier today and found a nice middle of nowhere place to eat, great home-cooked food. Anyway, here is a side shot with my cargo bag nicely hiding my servo (look closely at the shadow, you can see my favorite modification I've done to the GRiSO ... highway pegs!!! Very nice for me, 6' 1" with long legs)
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In the end, the CC worked really well all day, it could use some additional fine tuning to be closer to a full range of control. But as it sits right now, it works very well in 5th & 6th around 55+ mph. Most all my usage of it is between 70-80 mph and it engages quickly and does a really good job maintaining speed despite hills, wind, etc. If you manually speed up to overtake, it returns to the last set speed nicely and calmly. The +/- increments work really well too. I didn't use them that much, as i usually just pick a speed, set it and forget it.

But i have read other people have theirs working down low 30 mph or so. Mine likes to surge a bit down there, tried a few different times. But for me, it all my riding, I don't think I've ever wanted to have cruise for anything other than highways. So, i may not mess with much for now. I'm really happy with it currently, just wish I bought it sooner!

Moto, thanks again for sharing your write-up. Your dip switch settings were very helpful

Tim

Great job! I'm glad to have been of some help.
Thanks for sharing your installation details.
You'll love your CC, I bet. Happy cruising!
Moto