How I Survived A Dead SRAM eTap Battery
Ok – so the headline may be slightly dramatic… but here’s what happened to my shifting and how I saved the ride when the battery for my rear derailleur died on my SRAM Red eTap electronic gruppo.
Watch this video to see my on-bike experience, and see more videos at the PEZ Youtube channel here.
I’ve been riding this SRAM eTap on a Cipollini MCM project bike I built up a few months ago, and have yet to experience the dreaded battery failure while on a ride.
But this day, as I began my climb up the lower slopes of local Cypress Mountain, I noticed that the bike simply would not shift when I tapped the left shift lever. I tried the right lever to actuate a down shift, and the same – no response.
Luckily the bike was already in my 34×25 second gear – and locked in there thanks to the dead battery – so climbing was not a problem. I was however, thinking about how long it would take to get back home – up and down several hills and about 10km away – with only this one gear.
Then I remembered the system has two batteries – one for each of the front and rear derailleurs. (Doh!). One thing I like about the SRAM eTap system is that both batteries are identical – so swapping them in cases like this easy.
I pulled over, easily unclipped the batteries and swapped the juiced up front battery onto the rear mech. Power was restored instantly to the rear, with the full range of 11 rear cogs at my disposal for the ride home, while the front mech was rendered useless – not a worry in the 34t chainring, as I still had plenty of gear options to work with.
Of course, the rear battery will drain its power long before the front (in most cases) given the higher number of shifts I make on the rear cassette. So even before I stopped to swap batteries, I was confident I’d have enough juice to get home with the 11 speeds on the back.
Descending some of the hills on my return route – I found myself riding the 34×11 – something I rarely do because I’ll engage the 50t big ring when the chain is somewhere around the middle of the cassette, to avoid too much chain deflection from the front to the rear mech. This is roughly the same as riding a 50x16t or 17t ratio, and actually worked out quite well, in that I didn’t end up spinning out like I thought I might.
As an addendum to this story – I dutifully charged the batteries when I got home – but neglected to reattach them to the bike before my next ride. As I’ve been showing Mrs. Pez the ropes of learning to road ride, we’ve been car shuttling to Stanley Park lately. On our next ride I only realized my bike was completely powerless after we’d unloaded the car to start the ride. So I spent the next hour spinning away in my 34 x 21. Lesson learned there as well.