I'm rebuilding my main ride again because small wheels loses me on a hardtail due to bad NVH with the crappy roads we have here. I want to run high tire pressure for maximum efficiency and range because i find
Lessons learned from small wheels ( 26" and under ):
The basis of v2 is a 21" size Motobecane Fantom Expert 29" from BikesDirect.
It's not light, but it's cheap ( $500 new shipped ) and has good geometry.

Wins on this bike:
Lessons learned from small wheels ( 26" and under ):
- Great power per lb of DD hub motor, however, mid drive or dual geared hubs is just as good, minus regen
- Weight balance of bike matters, >10lbs in the rear end = wagging, hard to handle, easily cross 70lbs, starting to become burdensome, evenly divided or central weight is so much better
- Tire selection is limited but not stifling, great selection of thick tires, but ~100w of loss though, better to accept the use of sealant and use tall tires to minimize rolling resistance
- Low tire pressure = big efficiency loss, big problem for a long range ride with today's battery technology, not an acceptable compromise to improve NVH
- Seat post not good enough to provide large improvement on NVH on a hardtail, larger wheels is the better answer, add seatpost and it's even better
The basis of v2 is a 21" size Motobecane Fantom Expert 29" from BikesDirect.
It's not light, but it's cheap ( $500 new shipped ) and has good geometry.

Wins on this bike:
- 460mm chainstays; puts the rider a bit closer to the front wheel so the front susp can help a tad
- Long reach means i can put more of my torso on the handlebars, this means also that a small front fairing would work
- Fits a 50mm seat post
- Lower than usual bottom bracket = better center of gravity and okay for the mostly street riding i do
- Large reduction of un-suspendable road judder on bad roads vs 26", major improvement to rider's quality of life.
- 20mm internal rims are a poor match for the stock 29 x 2.25" tires so i will downgrade to 29 x 1.75
- Fork too hard on the lightest setting, front NVH suboptimal. need an air fork again
- Goal is to be able to sustain up to 35mph on semi-flat ground whenever needed and accelerate briskly, on 9-10lbs of total motor
- em3ev 52v 20ah batt
- Lightest.bike mid drive @ the currently crippled 900w power limit - may run external controller for 1400w since warranty's expired
- 4-5lbs super low turn count dual reduction geared hub on the front wheel at 350w max for nice safety margin on an aluminum air fork & no hub -> cassette interface shearing potential, AWD is bonus
- Does a 4-5lbs front hub hurt front NVH?
- Effective front fairing
- Maybe tail fairing
- Perfect middle ground between minimum amount of rubber in sealant for adequate goathead resistance
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