Rostra help

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1911

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If you've got a Rostra that works, please tell me how you've got your dip switches set (all 12).

My VSS wire is tapped into the ABS/ECU comm wire (white/yellow). Tach wire into orange at coil. Passes all diag tests. When I try to set speed I get a couple of "bucks" and then nothing. Currently set at highest pulse rate.

Thanks in advance.

 
off-off-on-on-off-off-off-off-off-on-off-off

must have relay for brake wire [page 22-c]

I had random drop outs until I disconnected and grounded the dark blue tach wire..[page 18-e] not concerned about the over- rev disconnect

it has been working very well for a year now----slight surge on downhills..if it bugs me I hold the throttle steady..

 
I used the ABS sensor at the ECU. I didn't use a tach wire, either. Your sig says 2007 - is that correct? I understand that 2008+ bikes need a pulse divider to use the ABS signal.

Off-Off-On-On-On-On-Off-Off-Off-On-Off-Off

2015-01-17%2023.10.13-M.jpg


 
Last edited by a moderator:
@lnewlf: I think your speed sensor is set too low. My research indicates that the pre-2008 FJR speed sensor pulses at around 81000 pulses per mile (100 pulses per rear wheel rev, ~814 tire revs per mile), which is at the upper limit (way over, actually) of the Rostra's capability. Max is ON-ON-ON-ON at 38,600 pulses/mile.

 
Last edited by a moderator:
@lnewlf: I think your speed sensor is set too low. My research indicates that the pre-2008 FJR speed sensor pulses at around 81000 pulses per mile (100 pulses per rear wheel rev, ~814 tire revs per mile), which is at the upper limit (way over, actually) of the Rostra's capability. Max is ON-ON-ON-ON at 38,600 pulses/mile.
yeah-gonna check that...I was using a signal divider in an effort to get rid of the random dropouts which didn't help so I took the divider off...grounding the tach wire cured the dropouts and I never reset the pulse rate...anyhew it works great set at 8000 ..My research indicates about 35000/mile [ if I remember correctly there are 43 teeth on the ABS tone wheel x approx 814 wheel revs / mile =35000].

 
@lnewlf: I think your speed sensor is set too low. My research indicates that the pre-2008 FJR speed sensor pulses at around 81000 pulses per mile (100 pulses per rear wheel rev, ~814 tire revs per mile), which is at the upper limit (way over, actually) of the Rostra's capability. Max is ON-ON-ON-ON at 38,600 pulses/mile.
yeah-gonna check that...I was using a signal divider in an effort to get rid of the random dropouts which didn't help so I took the divider off...grounding the tach wire cured the dropouts and I never reset the pulse rate...anyhew it works great set at 8000 ..My research indicates about 35000/mile [ if I remember correctly there are 43 teeth on the ABS tone wheel x approx 814 wheel revs / mile =35000].
40 teeth.

 
even better then...40 x 814 [i think mine is fewer with a 190/55 tar] is approx 32500...

 
This is my next project. Where did you get yours. I found one at Summit Racing, but it indicated it was for GM products only. Does that matter? I've been WAY too long without CC.

 
2008 here. I used the speed signal from the ECU.

Here i what I have from my notes for switches.

Gain Sensitivity
1 off
2 off extra low

Pulses/Mile
3 on
4 on
5 on
6 on 38600 (24000)

Engine/SetUp Timer
7 off
8 off
9 off 8 cylinder / low


10 on Square wave

Trans type
11 on Automatic

Switch type
12 off Open circuit

 
This is my next project. Where did you get yours. I found one at Summit Racing, but it indicated it was for GM products only. Does that matter? I've been WAY too long without CC.
Nope... doesn't matter. Rostra may put together a kit that aimed specifically for GM projects, but the core unit will be the same.

 
THANKS all. Before the replies started I changed the engine setup/timer from 4 cyl to 8 cyl (wasted spark ignition?) and that made the system usable but still a little quircky.

Cutting and grounding the tach wire made the system work flawlessly. Don't know how I'd have made it out to YFO without it. Best 200$ and 38 hours
uhoh.gif
I've spent on the FJR

 
Hi guys! Anybody ever installed a Rostra cc on a FJ 09? After succeeding with 2 installations on FJR (2005 and 2012), I just completed one on a FJ 09 2015, It works but it is somehow very tricky to have it keeping a steady speed, specially going downhill. The speed variation is only 2-3 mph, but change is not smooth at all. Do you think cutting and grounding the tach wire (dark blue) would be the solution? DIP switches setting that work best seems to be : 1-2 off, 3-4-5-6 on, 7-8-9 off, 10 on, 11-12 off, same as for most FJR.

Thank you.

 
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