I test rode a "new" 2010 Trek FX+ from my LBS as a potential commuter for my 18 mile hilly ride to work. The LBS put a new battery on it just months before. I fully charged it before my test ride. The ride to work is mostly downhill; I used the assist for perhaps 3-5 miles total, pedaling unassisted the rest of the way. I'm just 140 lbs, 5'6" and in excellent shape for a mid-fifties guy.

On both occasions, with only moderate use of the assist, the battery charge display went from full-except-one-bar to 0 bars at mile 16 and 18 respectively.

My questions: Is it normal for a Bionix battery to cut out like that from nearly full to nearly dead in 3 minutes? Am I unrealistic to make an 18 mile hilly commute on a Bionix-powered Trek FX+ bike? Any suggestions for my LBS to fix this if it is indeed "broken"? Really disappointed as I don't have the time or interest in building my own. Thanks for any answers, suggestions, and advice you might offer.

We're Trek FX+ owners, my husband rode his coast to coast. What you describe is not normal, our battery lasts for 20+ hilly miles or 10+ of uphill mountain pass using it the whole way @ level 1. Using electric @ level 3 or 4 WILL eat up the battery that fast. Unfortunately, I'm not techie enough to hazard a guess about what's wrong with yours. The one time when Don's battery didn't work at all, it needed an "update" from a shop that had the update software. Those shops are few & far between, not even Eugene OR had one. Trek's FX+ guru who figured this out by phone is David Studner (800) 313-8735 ext 1204 or 12104, david_studner@trekbikes.com

One other thought. Keep riding and see if your assist is truly gone or it's just the battery display crapping out. A couple times when Don's display seemed to crap out early, the assist lasted for many miles more.

You should easily make 18 miles on 1 charge even using the assist all the way, since you only used it for 5 miles of assist out of the 18 there is something not right with the set up.... (now it does depend on how big those hills are)

Thanks, Yumadons! I don't own the FX+, but if my LBS is willing, I'll ask them to call D. Studner at Trek to figure it out.

BTW, I had read your travel posts previously. Very impressive "Trekking" you've done! Many thanks.

The total climb is about 600' to work; maximum grade is 15%. The ride home is about 1,100', but the battery gave out just getting to work. Thanks for the info!