Motor/ frame combo options

[gcm9999]

Skip to last paragraph to avoid details. I'm planning my 2nd build. 1st build went well with Salsa Muk Luk Ti fitted with a BBSHD, Advantix drivetrain (highly recommended) , Lekkie crank and chain ring parts . Biggest concern was chain line which turned out great using all 10 speeds w/o any issues. So why replace a good working fat tire e bike? For several reasons I want a lighter bike and can afford it now. By my research I can purchase a much lighter complete carbon fat tire bike (such as a Salsa Beargrease or Trek Farley or?) and fit a CYC or BBS02. This gets me in the 46 +/- lb range with battery vs the current Salsa Ti BBSHD tank at 60 lbs. I would swap wheels and motor to lighten the Salsa Ti a bit but the wheelset (26" QR Sun Mulefut ) are new and no one is making QR 26" carbon wheelsets. And , it would only drop the weight by 3.5 lbs.

So, can anyone chime in with experience and or knowledge on building a Trek Farley Carbon , Salsa Beargrease Carbon with either a CYC or BBS02? My riding style is that I don't use throttle much at all , currently ride the BBSHD at Level 1 or 2 (rarely) . I do all I can to get the most range and I weigh in at 150 lbs. I regularly tow my kid around on a sled over smooth snow covered streets and seldomly pull a (dead) antelope or deer out of a field in a sled as well. Which doesn't take much power. The terrain I ride is a bit hilly with some occasional longer but not very steep climbs on rural and 2 track BLM roads similar to gravel riding but over snow.
Thanks

 

[gcm9999]

I believe the BB on the Pivot Les Fat is 132 MM wide (as wide as the tires!) If so, does this eliminate the possibility of using CYC Photon or any other mide drive?

 

[GoFastGus]

Hi, welcome to ES! I’m also toying with the idea of a fat tire e-bike build. I’ll keep an eye out for any future updates!

For several reasons I want a lighter bike and can afford it now. By my research I can purchase a much lighter complete carbon fat tire bike (such as a Salsa Beargrease or Trek Farley or?) and fit a CYC or BBS02.
This gets me in the 46 +/- lb range with battery vs the current Salsa Ti BBSHD tank at 60 lbs.

I’m curious why you’re interested in making this e-bike as light as possible. Frame material is probably one of the last places I’d want to save weight. Carbon fiber is especially poor in compression and has a short fatigue life (to my non-engineer understanding). In terms of fatigue life, my understanding is the top choice for e-bike builds is steel, followed by aluminum.

I would swap wheels and motor to lighten the Salsa Ti a bit but the wheelset (26" QR Sun Mulefut ) are new and no one is making QR 26" carbon wheelsets. And , it would only drop the weight by 3.5 lbs.

Haven’t done too much reading into carbon wheels, but I imagine they would suffer from similar problems to the frame.

I regularly tow my kid around on a sled over smooth snow covered streets and seldomly pull a (dead) antelope or deer out of a field in a sled as well. Which doesn't take much power.

I’ve never towed with an e-bike before, so I can’t speak to its efficacy. If you’re planning on regularly towing an extra load behind you, why does weight reduction matter so much? Also worth noting if you’re planning on towing anything on an e-bike, you should have a way to slow both you and the thing you’re towing safely. Not sure what your potential brake setup will be, but something to keep in mind.

Sorry to be so critical in the first reply to your post, I’d love to see some photos of the previous build!

 

[2old]

I don't think that carbon is a bad choice for an "e" (based on the fact that most high end OEM's are carbon), but I think the thicker bottom bracket on some "analog" carbon frames could be a problem with the BBS. Karl Gesslein @ electricbike-blog.com wrote a lot about these conversions.