Looking for advice on a bike computer

@stevemz I would guess that the likely cause of the differences in NP and TSS has to do with what each of the applications does with certain data.

As you know, Andrew Coggan’s algorithm for calculating NP is the 4th root of the rolling 30sec averages raised to the 4th power (simplified wording: see p.120 of Training and Racing . . . ). So when the applications run the algorithm, there are several pieces of data for which the software needs to make decisions that may be handled differently by the different apps (presuming they all implement the formula correctly), including start of file, end of file, pauses, and spikes. As TSS is derived from NP, then if NP is high, TSS will be as well (you can see this in your Element data).

The only app that is “certain” to be accurate is TrainingPeaks (and, of course, WKO4) as it was “certified” by Dr. Coggan to correctly implement his algorithm. So errors in TP results would come from bad data.

A more controlled way to compare the units would be to create a new .fit file (from an effort) that has no pauses or backpedaling; import it into WK04, identify the start and end of your effort (where the first and last recorded wattages are located), delete all data points in the .fit file prior to and after those points, and reimport the updated .fit file into the apps and see if the NP and TSS results are the same. [note: I have used this approach successfully to remove power spikes where I know, for example, I didn’t generate 2x pMax).

As for 30sec max and KJ there seem to be no standards, such as with NP and TSS, such that one app could be presumed to be better than the other.

As you can infer above, WK04, for me is the gold standard for all power-based data and use it (and TP Premium) for all cycling (and multi-sport) data analytics. For users new to power-based metrics or don’t have the time for a deep-dive understanding of what TP/WK04 provides, I think TR has done a great job at simplifying all of it and providing a subset that they feel is necessary to help users become faster cyclists. So even if the analytics aren’t perfectly accurate, it is likely that it is “close enough” and consistent from effort to effort.

I didn’t know you could see the TSS on Garmin Connect. I just looked on the app where is it. Is it only on the website?

Thanks @bbarrera. I don’t have a power meter yet. That explains it.

Bryton 530

I had no issues with my Lezyne Macro, my so uses a Bryton Rider 310. If you are looking for solid, budget conscious computer, I would highly recommend either.

Another vote for the Wahoo Elemnt Bolt. First computer after many years of riding and can’t see how I’d need more. Gives you all the power info you could want along with basic outdoor riding metrics and GPS.

The hardcore Strava and/or data nerds may want more but should suffice for the rest of us.

Bonus: The “limited edition” colors can be found at a nice discount online. Picked mine up from Excel.

Couldn’t agree more. I picked up a lightly used one in perfect condition for AU$75 as a spare, too. Simply don’t see a reason to get anything else.

Wahoo are the best deveices for a bike.

In the end I went for a 820 explore which was on sale but I can’t find how to connect it to my power meter, anyone help

Did this work with your PM? It looks like this might not be the best computer for use with a power meter.

Eventually after I gave sigma sports a massive bollocking for not listening to what I wanted at all I got an upgrade. I was really pissed off though.

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Any of you Bolt users have experience with 200 mile events? I’m tackling DK200 this year and estimate an 18 hour finish time. I have a 3350mah and 5000mah backup battery…trying to save weight and leaning toward carrying the 3350mah for the final leg. I’d like to use turn-by-turn navigation so I don’t have to read cue sheets. Just wondering which battery backup option would get me to the finish?!



I don’t know what the exact mah of the Bolt battery is, but you’d easily be able to charge it multiple times fully with the smaller external battery. For what it’s worth, DC Rainmaker tested the battery life and found that the 15 hours battery life was pretty well spot on.

I’d have thought 3350mah would be plenty. Are you going to be charging anything else during the DK200?

Thanks DJ! I haven’t checked out the DCR review yet and am not too savvy on electronics. Good to know that the “as advertised” hours are legit. I’ll only be charging the Bolt for DK. Appreciate the quick response!