Our club is seriously considering adding RPM monitoring to the classes that have RPM limits. This probably would be in the form of a magnetic pickup (MPU) wired to the back of the pullling tractor with a plug to connect to the monitor on the sled. My question is, how do you do this with an SFI approved vibration dampener? Do these monitors use magnets on the dampener? I believe that modifying a dampener would likely violate the SFI approval. How have others complied to this requirement? A search of this site has shown that at least two blips are necessary to be accurate due to oscillations in crankshaft rotation causing inaccurate readings. If two are used they would have to be exactly 180 degrees apart to get accurate readings. How the data is recorded and analyzed will make a big difference on the results and may cause unwanted disqualifications. What other real time methods have been used or tried to keep RPM in check? http://www.pulloff.com/phorum/read.php?2,326298,326298#msg-326298 Fri, 15 May 2026 10:25:23 -0700 Phorum 5.2.23 http://www.pulloff.com/phorum/read.php?2,326298,326460#msg-326460 http://www.pulloff.com/phorum/read.php?2,326298,326460#msg-326460 Sascha Pulling Forum Wed, 15 Feb 2023 08:34:53 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326458#msg-326458 http://www.pulloff.com/phorum/read.php?2,326298,326458#msg-326458 Could definitely see times it would be nice to see it right off the track rather than having to download runs to laptop]]> kevehr4020 Pulling Forum Wed, 15 Feb 2023 07:22:01 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326457#msg-326457 http://www.pulloff.com/phorum/read.php?2,326298,326457#msg-326457 https://isspro.com/installation/236B%20-R8906.pdf]]> MLP Pulling Forum Wed, 15 Feb 2023 06:04:08 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326448#msg-326448 http://www.pulloff.com/phorum/read.php?2,326298,326448#msg-326448
Single magnet system gave out false readings in acceleration - and actually, people stepping on the clutch at the end of the run etc. gave peaks, too. This ended up in the monitoring system being given certain margins and that then turned into pullers trying to find out how high those margins were, creeping up in rpms over time.
So now with the tablet, there is a clear graph for everybody to see and you can tell whether somebody was going down the track over the rpm or if it just went over when the driver hit the clutch at the end of the run, when he was standing still already.]]> Sascha Pulling Forum Tue, 14 Feb 2023 23:56:34 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326443#msg-326443 http://www.pulloff.com/phorum/read.php?2,326298,326443#msg-326443 [You should specify pullers to use the ISSPRO R8906 magnetic pickup. It comes with 2 magnets, but 1 is plenty. ISSPRO instructions says to mount the magnet on the face of the balancer for best results, however it can also be mounted to the OD with success. FYI, if you were to use 2 magnets they do NOT have to be mounted 180 degrees apart. The ECU calculating the RPM is merely counting pluses and dividing by the number of magnets to get revolutions.]

-The ISSPRO instruction sheet does not specify in writing where to mount the 2 magnets other than 180* apart…. Although the diagram provided suggests that the magnets be mounted on the OD of the balancer, rather than the face??? I’m not sure what instructions you’re referring to, as I just looked to make sure I didn’t install incorrectly.]]> IHRED Pulling Forum Tue, 14 Feb 2023 18:28:48 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326353#msg-326353 http://www.pulloff.com/phorum/read.php?2,326298,326353#msg-326353 turbo Pulling Forum Sun, 12 Feb 2023 12:59:41 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326335#msg-326335 http://www.pulloff.com/phorum/read.php?2,326298,326335#msg-326335 RCP Pulling Forum Sat, 11 Feb 2023 23:19:24 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326334#msg-326334 http://www.pulloff.com/phorum/read.php?2,326298,326334#msg-326334 RCP Pulling Forum Sat, 11 Feb 2023 23:17:44 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326332#msg-326332 http://www.pulloff.com/phorum/read.php?2,326298,326332#msg-326332 MLP Pulling Forum Sat, 11 Feb 2023 20:48:55 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326328#msg-326328 http://www.pulloff.com/phorum/read.php?2,326298,326328#msg-326328 Those sound like they both showed the same thing, they were illegal.]]> Dirtfarmer Pulling Forum Sat, 11 Feb 2023 19:03:07 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326325#msg-326325 http://www.pulloff.com/phorum/read.php?2,326298,326325#msg-326325 RCP Pulling Forum Sat, 11 Feb 2023 18:09:19 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326315#msg-326315 http://www.pulloff.com/phorum/read.php?2,326298,326315#msg-326315 redundant Pulling Forum Sat, 11 Feb 2023 15:29:25 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326313#msg-326313 http://www.pulloff.com/phorum/read.php?2,326298,326313#msg-326313
I have a background in data acquisition and data analysis, how the algorithms are written, and the frequency of the data collection can make a big difference in how the results are presented to the observer. This is especially true when looking for maximum values in a data set.]]> RCP Pulling Forum Sat, 11 Feb 2023 13:14:19 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326305#msg-326305 http://www.pulloff.com/phorum/read.php?2,326298,326305#msg-326305 MLP Pulling Forum Sat, 11 Feb 2023 09:18:03 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326304#msg-326304 http://www.pulloff.com/phorum/read.php?2,326298,326304#msg-326304 Dairy blend Pulling Forum Sat, 11 Feb 2023 08:21:19 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326299#msg-326299 http://www.pulloff.com/phorum/read.php?2,326298,326299#msg-326299 tach, Pulling Forum Sat, 11 Feb 2023 07:09:09 -0800 http://www.pulloff.com/phorum/read.php?2,326298,326298#msg-326298 http://www.pulloff.com/phorum/read.php?2,326298,326298#msg-326298
My question is, how do you do this with an SFI approved vibration dampener? Do these monitors use magnets on the dampener? I believe that modifying a dampener would likely violate the SFI approval.

How have others complied to this requirement?

A search of this site has shown that at least two blips are necessary to be accurate due to oscillations in crankshaft rotation causing inaccurate readings. If two are used they would have to be exactly 180 degrees apart to get accurate readings.

How the data is recorded and analyzed will make a big difference on the results and may cause unwanted disqualifications.

What other real time methods have been used or tried to keep RPM in check?]]> RCP Pulling Forum Sat, 11 Feb 2023 06:40:29 -0800