Specialized SX Trail With Cyclone

[Nacent]

This is the final iteration on this bike. The current setup runs 1500W continuous through a phaserunner into a cyclone. The drive train is single speed with very strong acceleration up to a top speed of 55 km/h. Its perfect for high speed and technical single track trails and i usually get around 35km per charge.

I designed and built all of the mounting and some of the drive line components. The mounts are a composite of 7075 aircraft aluminum and 30% carbon fiber reinforced nylon with elastomeric rubber between the frame and printed components to prevent vibration transfer from the motor to the frame.

 

[tangentdave]

Very nice. No attachment to the BB at all?

 

[Nacent]

I tried that it, didn't work that well the motor torque would twist it out of alignment i have two aluminum plates that loop around the bottom bracket.

 

[Skaiwerd]

Do you no longer need the chain tensioner? Don’t think it’s under the cover. I think it’s been eliminated and you tighten the chain by moving the motor and mount up the down tube, good idea. Is that a motor bash guard in the cad render? It’s not in the bike photos.

Edit
I do see it’s fixed to the bottom brackets as you mention

 

[Nacent]

I have a mounting point for a spring loaded chain tensioner under the cover but i don't really need it so i removed it. I sized the distance so a half link chain fits well with the right amount of slack and i use a narrow wide chainring along with a a little bit of throttle at rest to preload the driveline. the cover also has internal paths that help maintain the chainline. I haven't put alot of time on this iteration of the drive line to see if chain stretch is going to be an issue, but if it is i can bolt on the chain tensioner in 5 min.

Haven't made the bash guard yet waiting on some material something called pctpe has really good impact resistance.