Review: Dynatek DSPT-1 Ignition Module

[PSEBYL]

I haven't read about any 883's using the Dynatek DSPT-1 ignition module (only a few 1200's), so here are my observations.

I replaced my stock ignition module because my bike would frequently have carb farts when blipping the throttle while decelerating, particularly when down shifting from 2nd to 1st gear (too much timing advance at low RPM). Not cool when rolling on throttle in a turn!

I originally considered both the Dynatek DSPT-1 and the Daytona TwinTec TC88A. I favored the DSPT-1 for the following reasons:
1) Cost. The DSPT-1 is $100. less than the TC88A.
2) Simplicity. I wanted a plug-n-play ignition module. I don't need the user programmability, or data logging features of the TC88A.
3) Specifications. The DSPT-1's advance tables are factory programmed specifically for a Sportster, versus the TC88A's advance tables being pre-programmed specifically for a big twin (with claims to being compatible with a Sportster).
4) Support. Dynatek was very friendly and helpful to my inquiries pre-purchase. Daytona TwinTec was very cold and impersonal to the same inquiries; I felt like I was corresponding with a rock.

Research:

I compared advance table charts from Daytona TwinTec and Dynatek. The nominal timing values are quite different. For example, the TC88A with setting #5 provides 24° of advance at idle versus the DSPT-1 which provides 12° of advance at idle; a big difference. The DSPT-1's selectable advance curves, in the nominal range, are very close to the custom curve(s) that Turbota developed for the TC88A.

I was concerned about the DSPT-1's non-adjustable VSS frequency of 1356 hz @ 60 MPH. I assume this frequency was chosen to split the difference between the 883's factory VSS frequency of 1381 hz, and the 1200's factory VSS frequency of 1338 hz. BEWARE…the DSPT-1 will only provide an acceptable amount of speedometer error for a 2004-2005 Sportster. The DSPT-1's VSS frequency, as developed for the "new" 2004 Sportster, did not account for the future change in the 2006 Sportster's transmission (see 061200c's issue with his 2006 Sportster with DSPT-1 here http://xlforum.net/forums/s...ad.php?t=29669 ).

Usage:

The DSPT-1 has 16 user selectable advance curves in 4 separate groups, using 1 rotary switch:
Group A) 4 curves for stock motors.
Group B) 4 curves for high torque motors (>1 ft. lb. per c. i. @ 2-4K RPM).
Group C) 4 curves for turbo and nitrous applications only.
The 4th group of 4 curves is described as retard curves, which Dynatek neither defines nor even mentions using in their instructions.
The first 12 curves are named for their timing value at WOT (for example, 34A = 34 degrees of advance at WOT, group A). The procedure is to use the highest advance curve, in the appropriate group, without pinging. The other rotary switch adjusts for 8 different RPM limits ranging from 6250 to 8500.

My results:

The first thing I noticed is that the “check engine” light doesn’t illuminate for the first few seconds once the key is in the ignition position. Maybe it doesn’t support H-D’s diagnostic monitoring? I recently added the H-D tach kit; there was no change in tachometer functionality, or any indicator other than the “check engine” light.

I started with the 34A setting, then switched to the 36A setting, without telling much of a difference. Then I tried the 38A setting. Immediately, I could feel an improvement in off-idle throttle response. Once warmed up, the rhythm of the idle seemed to be smoother as well. At cruise, I felt a slight reduction in engine vibration at steady state throttle @ 3K RPM. No perceptible difference at WOT. Speedometer error with the stock module was 1% slow, and now with the DSPT-1 it’s 1% fast.

Returning home, there are few slow speed turns, including my driveway, which usually yield 1 to 2 carb farts while blipping the throttle on decel. I didn’t get a single one! I even tried to cause them. Once parked in my driveway at idle, I thought surely I could force a carb fart by whacking the throttle open. I tried several times. NO CARB FARTS! The engine just responds in kind. I couldn’t believe it!

This ignition module did not provide any real seat-of-the-pants performance improvement. It did, however, provide a more tractable throttle, which improves the drivability and enjoyment of my bike. Was it worth the $189.? It was for me just to get rid of the carb farts.

[1Ray Hewett]

As long as the farts don't smell, I can live with them.

[milmat1]

Great report !!

Let us know if you find out about the engine light !! I'm curious now !!!!

[Weo]

Thanks for the info!

[flip21boards]

I ended up getting one. They work great! I have a 04 sporty with a 1200 conversion 9 5 1 compression. my bike really woke up around 28b and 30b.

[runnermedic]

Old thread but this module still on sale.
Found this:
The problem of losing the check engine light is because this module does not save or transmit information through the diagnostic port, the Grn / V cable that goes from the module to the port and then to the speedometer is dead. Compared to the original module, it presents changes in voltage that are translated into data. If you want to know the status of your motorcycle you must use the speedometer diagnostic method and there you can see the saved codes. The lack of this module not having the communication function through the j1850vpw + protocol causes the loss of making diagnosis and not sharing data such as rpms, gear position voltage, security system and other data. In reality, the benefits are few and to top it off, it takes away functions. So the other option would be tc88 or go back to the original module if you want to keep these options. If there is a better option and someone knows about it please share it.