anyone using one of these or both…what is the real difference. i m looking at buying the amateur and i would like to know if anyone used it and are happy with it… all the athlete i know are using the professional one …is the difference of price justified
thanks
the difference is in the extra strain gauges which result in different claimed accuracy (Pro 2%, Amateur 5%). other than that, they are the same cranks, same computer, same software. is it worth the extra $? probably not. did i buy the pro anyway? yep
anyone’s riding the srm amateur???
suggest you post on the wattage forum - you can probably even find a 2nd hand SRM unit thru this group
I have been using the Amateur version for over 2 years with absolutely no problems, and I live deep in the heart of Bavaria where there are few sunny dry days.
The two main differences, IMO, are the weight and the slight increase in accuracy. The pro is moderately lighter, and as the other poster said it has more strain guages which supposedly increase the accuracy. I don’t know how easy it is to tell if you are getting 95% or 98% accuracy. I just don’t see how a normal person would need to spend the extra euro to get the pro version.
That is all well and good, but the new Dura Ace version is too sweet and enables the user to utilize the new BB design, which improves the performance of the crankset tremendously, IMO.
Jack
I just don’t see how a normal person would need to spend the extra euro to get the pro version.
That is all well and good, but the new Dura Ace version is too sweet and enables the user to utilize the new BB design, which improves the performance of the crankset tremendously, IMO.
Jack
why does a normal person need the amateur if you look at it that way. the purpose of this tool is to train the most efficiently you can. in that case the pro is the only one that makes sense. if you can’t justify the extra couple hundred dollars when you are already spending a few grand then you shouldn’t probably be buying either, get a power tap or a polar or something. if you are looking for the best the pro srm is it.
as for the new bb design… no performance improvement over the octalink what so ever. if you can flex a 9sp bb and crank then you shouldn’t be a triathlete you should be in the world strongest man competition pulling a train or something. the new system looks way better and is probably a bit lighter.
The main issue is that with the Amateur version, the slope may drift quite substantially over time. This may cause confusion as to what your exact power is when you use it. The drift can be quite bad with some of the Amateur models, and in my experience they need calibrating on a regular basis – maybe once every four to six weeks.
Calibration involves using a known, certified mass and hanging it from each pedal at four different points (12, 3, 6, 9 oclock) using this info http://www.srm.de/Online_Manual/SRM_English_Manual/PMCalibrate.htm
The Pro still needs calibrating like this, but on a much less frequent basis – maybe once every 6-months.
With the Amateur there is often big discrepancies between each crank.
Additionally, to check the linearality of the cranks, you may want to use several different masses, repeating the four point check on each cranks several times.
Maybe after a fair period of time (likely > 12 - 18mths) you may not need to do these calibrations as some of the issues is possibly due to the epoxy resins hardening which hold the strain gauges in place.
Finally, if actual accuracy is important to you, you should perform these calibrations when you get the unit, as frequently they don’t come well calibrated from the factory.
Due to some large left/right crank differences i would not recommend or use the Amateur version if accuracy and reliability is important to you. I would thoroughly recommend the Pro SRM (and i also recommend the Power Tap).
Ric
For an athlete at your level, Jonathan, you should worry more about getting used to your new skinny tire bicycle and working the “Shifters” or “Clickers” as you call them. Power Meters are waayyy out of your range.