Speedo Wars – A Little Hope…

May 6, 2009 · Posted in Racing, Touring Cars · by ed

So, Mr Simon has given me a log-in to add some blog post’s to rcLazy… There’ll be some nationals reports coming later in the year, but to kick things off, I thought I’d natter about speedo’s… no, not the swimming trunks, the Electronic Speed Controls (ESC’s).

With the recent advent of brushless within our sport (the first Novaks were only avaliable in 2006) technology has been moving on rapidly. The first ESC’s were pretty good, although had a tendancy to overheat if pushed hard, and it took a while for the new technology fangled to get a hold. For example the first brushless world champion was only crowned in 2008! However, with such rapid development, all major classes are now brushless, with the ease of maintenace being the real advantage (brushes, what are they… things you clean a car with right? ).

Anyway, to make it a bit easier, if we call the early pionears Gen1′s (such as the GTB and original Sphere’s), and the later models (such as the Sphere TC, and GM90) Gen2, we’re now getting onto the Gen3′s….

Ok, so where’s the issue?? Surely the latest and greatest should be the best, correct? Not necessarily, as it depends quite a lot on the classes raced…

Quite simply, there are a lot of different types of speedo’s out there currently, and as such there is a lot of confusion over whats best for what. Hopefully I can help outline the differences a little better, and make any choice easier.

In essence the Gen3 speedo’s can be split into two catagories;

Those with dynamic timing advance and Those without..

Right, whats dynamic timing advance? It’s effectivly a clever trick a speedo does with the motor timing, where by the timing is advanced further as the motor gets further up it’s rev range. This gives a continuing increase in power, with more RPM.

Now most Gen2 ESC’s had the facility to advance the motor timing, however this was usually independent of the motor speed, and by a set amount. Using the example of the LRP’s, increasing the power profile would increase the static motor timing

So what are the options? All the following speedo’s can be considered Gen3 (in no particular order)

Tekin RS Pro
GM Genius 120
LRP SPX / Nosram Matrix Evo “Stock Spec”
Team Wave RB50
Speed Passion GT2.0 Pro

All these speedo’s have the ability to adjust the timing “on-the-fly”…

There’s one recently released that can be counted as a gen3, but doesn’t dynamically adjust the timing, and that is the LRP SXX/ Nosram Pearl. So where does this fit into the modern scheme of things… well this is where the classes raced come in!

For fixed winding stock classes (17.5, 13.5, 10.5) generally, there is capacity to burn in the cells… using a speedo with dynamic advance is great for these classes, as the extra power can be used. So any extra power that you can get out of the motor, is a good thing.

For unlimited/modified racing however, the easiest way to increase the power is to change the motor (not an option for the limited classes). And given that timing in modified is usually retarded to aid in driveability and run time, dynamic advance is not an essential requirement.

So, decision time… whats best for you? Well, I’m not going to tell specifically which speedo to run, as they are all very good, although they achieve the effects in different ways.

Well quite simply, if you do a lot of spec racing, then a speedo with dynamic timing advance will be a must.

For modified, dynamic advance really shoudn’t be a deal breaker, as the key points for that sort of speedo will be it’s efficency and driveability.

The interesting class to keep an eye in the coming year will be the 6.5/LiPo class, as it’s possible that with the restricted wind, the motor advance feature may be useful, or it could be too much for the motor/cells… something I’ll try to keep an eye on over the coming year. I’ll also try to keep people updated on whoose using what, and what’s popular… so expect it too get a bit techy everynow and then!

Cheers

(oh, and if your wondering… I’m running an Team Wave RB-50 )

Tags: ESC

Comments

One Response to “Speedo Wars – A Little Hope…”

simon on June 5th, 2009 19:11

Hey Ed, how’s the Team Wave RB50 going? I’ve just got my hands on one, got to solder it in yet, but looking forward to the turbo function. I also got the handheld programming unit, which has a USB socket, for the PC software that’s not yet released.