Recent content by mcdenny

New info regarding efficiency. Thanks @mschwett for suggesting getting a lot more low cadence 100/100 data. Big surprise to me anyway, at 100/100 and Pr above 85 watts the controller does NOT just dump in full voltage regardless of cadence. Just as with Pr vs Pm, there is a linear ramp up to...

Not at all, just ride the brakes.

The Spec mechanical power vs cadence is significantly curved. If you accept that the electrical power input is constant across the same cadence range then the efficiency curve is going to have the same shape. PS, I’m taking my bike in to get the new 2” more rise handle bar this afternoon and...

You can see the spec chart has a good bit more curvature. I did my best to match the spec chart in my spreadsheet to figure out an efficiency vs cadence function to use to adjust all my Pm electrical to Pm mechanical..

For reference here's the Spec charts for torque and Mechanical power

I haven't tried that experiment but your statement is correct - It isn't designed to work at that low rpm that means it's less efficient at that low rpm. It makes sense, The controller applies voltage against the resistance of the windings but the rotating winding themselves generate a current...

A short progress report: Here's how often a record occurred for a particular cadence. 0-10 have been deleted. (O was far and away the most prevalent cadence - coasting) In my ride analysis I'm going to use data for cadences 50 to 90. Eliminating the tails will make the slope and P...

Worked some on starting over with freshly downloaded data. The stats from 27 rides (48 miles, 3.5 hours) are smushed into a spreadsheet with 24 columns and 15,000 rows. I’ll start massaging it tomorrow but it will be a few days before I have something to share. A lot of filtering, pivoting and...

Jeremy: Q1. Yes, micro tune in all cases except the 100/40 ride which I don’t think I presented yet. For 100/40 I set “sport” to 100/40 with the app. Q2. When the map and the terrain are different, go with the terrain. All: (both?): I plan to redo the charts showing MECHANICAL motor power...

Another idea I have is that maybe the ramp functions should be forced to intersect Pr=0 at Pm=0. As I was analyzing the rides from yesterday I saw it could make a significant difference. _________ramp slope____Y intercept 20/20______0.24._________12.39 20/20______0.31__________0...

@mschwett , you were asking about Pmax at 80 cadence. Here's a chart from my 100/100 segment that shows the average and maximum Pm recorded per cadence. Pm max values are all about 400. The P mechanical would be P electrical * efficiency at that cadence. Probably all my Pr vs Pm charts...

Hooray, all the rides download using the ride.specialized.com browser link. It just the phone app that is buggy.

I did three more test rides this afternoon. 5 minutes at 100/40, 20/100 and 30 minutes ar 20/20. Unfortunately I could not download any of these 3 .fit files. As soon as I click “download” in the app I get an error message saying ”Sorry, can’t download. Try again later”. It never works later...

Jeremy, I eliminated all records with cadence < 60. The data at low power, low cadence is very noisy. Most of the records are in the 70s and 80s with relatively few 90s where I’m really pushing.

A new trial, a little longer and with more rider effort to more clearly define Pm saturation values. I just did 40/40 and 40/100. Summary from the Spec app: ____________________Distance______time_______avg MPH_______Adj Rider power______avg motor power Ride one...