Changed dip setting and improved Rostra

[C14lvr]

For those of you that have added a Rostra CC to your bike, I thought I'd share a change I made today that enhanced it's performance.

When I installed mine 2 years ago, I set the dip switches to the setting positions BDF had recommended in his tutorial. It's worked pretty good.

But, I've always noticed that certain situations would cause it to seem slow to react....
like, if I had it set at 70mph, and accelerated to pass someone. It would slow excessively, and take a while to resume back to 70. Or, when I would engage the cruise, and try to remove my right hand from the throttle, it had not achieved the speed setting yet, and might take 3-5 seconds to get there.

If any of this is sounding familiar to your experiences, then try this;
If your #1 and #2 dip switch settings are set to off, leave #1 off, but turn #2 ON.
That makes it work faster, and WOW! Mine now works so much better!
Far better response. I can literally engage it, and remove my throttle hand... that fast.
Now when it's set at a speed, and I add more throttle, it goes right back to the preset speed... as it should.

I'm diggin' the change now. If yours has been bugging you, ya might try it and see if it helps yours, too.
Bob

[jamiemac]

Great info!! I'll try that! That has been an issue for Me for years.

[VirginiaJim]

For those of us that have no clue, what does that setting change?

[martin_14]

For those of us that have no clue, what does that setting change?

probably the damping of the S-function used in the control algorithm.
Nope, I'm not kidding. One day I'll regret being able to know things like this. I'm thinking of Sheldon Cooper right now...

[VirginiaJim]

You're not up to Dietrich level yet, but excellent work so far...

http://en.wikipedia.org/wiki/Arthur_Dietrich

[B.D.F.]

Yep, those two switches control, more or less, proportional gain. Switches 7, 8 and 9 control, again more or less, integral gain. The settings recommended are indeed very sluggish and slow to respond and it is a compromise because usually when used at lower speeds and or lower loads, the bike will tend to oscillate in speed.

A similar thing will happen when changing switches 7 thru 9; the controller will respond with greater intensity when it is behind or ahead of the set speed but that can be a good or bad thing, depending on the bike's speed and load.

What is really needed here is two more DIP switches to control derivative gain which would give us the complete PID control algorithm. Unfortunately, the derivative gain is basically in the power- to- weight ratio of the vehicle and so is not usually needed but our application has a much higher power to weight ratio than any common auto.

It would be great if you would tinker around with that at lower speeds, different gears, etc. and let us know how it works. As I said in the tutorial, the settings given are absolutely not wonderful or even likely the best possible, just a group that works safely enough. If you (or anyone else) finds better overall settings, it would be great if you would share them.

Nice work and thanks!

Brian

For those of you that have added a Rostra CC to your bike, I thought I'd share a change I made today that enhanced it's performance.

When I installed mine 2 years ago, I set the dip switches to the setting positions BDF had recommended in his tutorial. It's worked pretty good.

But, I've always noticed that certain situations would cause it to seem slow to react....
like, if I had it set at 70mph, and accelerated to pass someone. It would slow excessively, and take a while to resume back to 70. Or, when I would engage the cruise, and try to remove my right hand from the throttle, it had not achieved the speed setting yet, and might take 3-5 seconds to get there.

If any of this is sounding familiar to your experiences, then try this;
If your #1 and #2 dip switch settings are set to off, leave #1 off, but turn #2 ON.
That makes it work faster, and WOW! Mine now works so much better!
Far better response. I can literally engage it, and remove my throttle hand... that fast.
Now when it's set at a speed, and I add more throttle, it goes right back to the preset speed... as it should.

I'm diggin' the change now. If yours has been bugging you, ya might try it and see if it helps yours, too.
Bob

[C14lvr]

Thanks, Brian.
I rode about 350 miles yesterday with a buddy of mine.
So far, so good. I still like the change. It's responding well, and a lot faster.

I haven't tried it yet at slower speeds, or lower gears yet...
but will do that, and report back with the findings.
Bob

[Rhino]

Great info. I'm also interested in lower speeds and maybe 4th. I have the settings from Brian's write up and find it oscillates a bit in 4th. I mostly use it at 60 and above in 5th or 6th.

[C14lvr]

Wow... Tulsa's been in a pretty bad state of drought for a while now.
Last week they said we were 8" behind for the year! (3rd year in a row...)

So... A buddy and I decided to do some riding this holiday weekend. We had a great trip to the Ozarks all planned... then, the day before we were to leave... Yep...rain.

It has rained here all weekend!

Hopefully, it'll dry up this next week, and I'll be able to report back on low speed, 4-5th gear response of the Rostra with the new setting.

(We have needed the rain, though!)