Using Two Range Extenders on One Ride - best practice? Specialized Creo SL

[JonFox]

Hello all, I am planning a ride of 80 miles and 3,000 feet of climbing and plan to use a good amount of Sport mode due to the "need for speed." I have two range extenders to bring with me and one will of course be connected when I start. The other occupies the downtube water bottle cage until needed. Is there a best practice to manage the change out of extender batteries when that becomes necessary? Option 1 is set MC to use RE first, and when the RE in the red, change it out, then proceed to use second RE until depleted, then I have the main battery fully available for the rest of the ride. Option 2 is use default, draining both main and RE until both are in the red, then install the fresh RE (of course, turning the Creo off when I do this). Any suggestions much appreciated!

 

[Nubnub]

If there is a better practice, it will depend on your ride and elevation profile. You are looking at 20 miles/750 feet climb per range extender and 40 miles/1500 ft average for the main battery. If most of the climb is early in the ride and/or I have hope that I could complete the whole ride with just one range extender, I would set the batteries to be used simultaneously. If you chose to deplete the range extenders first - you will have two instances where the available assist will be reduced when the range extenders near depletion. Or the third option is to change out the range extender and change Mission control to use both batteries simultaneously.

Again look at the ride profile to guesstimate where battery depletions may occur. If it is flat or on uphill sections where you feel confident you can climb worse case unassisted depleting the range extender first could be the way to go. On my Vado SL, the range extender reduces max assist by about half at <15% and to less than 1/3 at < 10%. This is unpleasant if it occurs during a steep climb but barely noticeable on the flats.

 

[JonFox]

@Nubnub, thanks for the great advice! I expected that I would need to change the RE before the first short climb just after 20 miles, but it seemed that I could go further on it, so I did. That was an illusion. I had elected to set Mission Control to deplete the range extenders first. However, MC did not ever start so at mile 43 I realized what happened (depleting equally on both batteries) and swapped out the depleted RE for the fresh one. Total mileage was 69 miles, 1880 feet of climbing, 20.8 mi/hr avg while fighting some winds. So at that speed/distance, two range extenders are needed. However I would venture that if one rode at 16 - 17 mph, or could draft off some buddies, the whole ride could be done with main battery and the one range extender. I'll need to repeat this ride down the road and make sure MC starts! Thanks again for the analysis - very helpful!

 

[kahn]

On my longest Creo (Aluminum) ride, I managed just under 53 miles and about 2,800 feet of gain with some steeper and extended hills in the mix. I did turn off the power (press/hold) the Selector Button when it seemed reasonable with downhills. That was with a Range Extender (RE) battery in parallel discharge. I think I had about 4-5% power left on the mixed battery arrangement. I've since purchased a second RE to potentially extended that distance but have not tried the "trio" on any rides. I'm definitely overweight which requires more power to move ME around and I'm also older so seem to need more assistance.

I hope you report your results.

 

[HLM]

Kahn, you don't have to completely turn off your power to save energy on the downhills. When you stop peddling downhill there is no power used. If you leave your TCU on there is a bare minimum use of power (put that in stealth mode but, truly, we're talking 1 or 2 watts per hour or so when not in stealth mode).
Also, for better power use, you can either switch power modes from the TCU as you ride on level, hilly or downhill or purchase the remote switch to do this more safely and more often if you need to.

On my longest Creo (Aluminum) ride, I managed just under 53 miles and about 2,800 feet of gain with some steeper and extended hills in the mix. I did turn off the power (press/hold) the Selector Button when it seemed reasonable with downhills. That was with a Range Extender (RE) battery in parallel discharge. I think I had about 4-5% power left on the mixed battery arrangement. I've since purchased a second RE to potentially extended that distance but have not tried the "trio" on any rides. I'm definitely overweight which requires more power to move ME around and I'm also older so seem to need more assistance.

I hope you report your results.

 

[Stefan Mikes]

Kahn, you don't have to completely turn off your power to save energy on the downhills.

He put the e-bike in the OFF mode (Assist Level 0). Not the power off.

 

[HLM]

He put the e-bike in the OFF mode (Assist Level 0). Not the power off.

He wrote, "I did turn off the power (press/hold) the Selector Button when it seemed reasonable with downhills." I interpreted this that he pressed and held the on/off button (electric power as opposed to the power selector) but I may have erred. Kahn will have to verify but it's all just a minor point.

 

[Stefan Mikes]

He wrote, "I did turn off the power (press/hold) the Selector Button when it seemed reasonable with downhills." I interpreted this that he pressed and held the on/off button (electric power as opposed to the power selector) but I may have erred. Kahn will have to verify but it's all just a minor point.

No, he pressed the top button that he calls the Selector. The one with "S" on it. It is equivalent to setting the assistance to Level 0 from the handlebar remote.

 

[JonFox]

Took a look at two 70 mile rides to the same destination, one ridden solo, the other in a five person paceline. 20 mph avg on both rides.
Power use solo =5.27 Wh/mi; Paceline = 4.5 Wh/mi. Range extender used on both rides. Pays to ride with buddies!

 

[kahn]

He wrote, "I did turn off the power (press/hold) the Selector Button when it seemed reasonable with downhills." I interpreted this that he pressed and held the on/off button (electric power as opposed to the power selector) but I may have erred. Kahn will have to verify but it's all just a minor point.

@Stefan Mikes is correct.

I did not turn off the power to the bike. I merely used the top button to turn the motor to NO assistance. Frankly, how that is different than NOT PEDALING I do now know. Other than if NO assistance is selected, if you start to pedal, you still get NO assistance. Whereas, if in Eco/Trail(sport) or Turbo, if you start pedaling you will get that amount of assistance.

And, I agree, it is somewhat confusing to sort out the terms. I guess there is MAIN power, the bottom button and the power mode button. I guess pressing and holding the "power mode" button should be termed "NO Assistance" as opposed to "no power"

By the way, I do now have the "remote" buttons on my Creo. Much easier than looking down reaching between my crotch!!!

Another by the way: The one time I set Mission Control to first deplete the Range Extender (RE), I was on a hill behind a friend and all assistance stopped when it reached RE cutoff. Now maybe I did not give it enough time, but it did not seem to switch over to the main battery. I had to stop and I UNplugged the RE. I don't recall if I turned off complete power or just did the UNplug. I was trying not to lose my friend on the continuing uphill.

 

[BioWheel]

Took a look at two 70 mile rides to the same destination, one ridden solo, the other in a five person paceline. 20 mph avg on both rides.
Power use solo =5.27 Wh/mi; Paceline = 4.5 Wh/mi. Range extender used on both rides. Pays to ride with buddies!

Thanks for posting your power stats for the similar rides - very interesting. Aerodynamics is actually the real deal. And the numbers seem similar to what is experienced with standard bikes.