Spīr Bikes Launches, Targets First Responders (Exclusive)


Electric bicycles have long been a good idea for first responders looking to navigate or control crowds. However, past designs placed all of the heavy drive train components to the rear of the bicycle. This weight plus the excessive weight (up to 70 lbs.) of gear that first responders carry, weighs down the backend of the bike. The result was sluggish speed, erratic balance, and poor battery life.

Due to the limitations of these designs, first responder agencies have not adopted the potentially powerful tool of electric bicycles.  Spir enlisted police agencies from New York, Indianapolis, and Chicago for help in reinventing the electric drivetrain. The result was a revolutionary drivetrain capable of performing in the toughest environments.

What we have here is a completely in-frame design, custom motor, controls, battery, frame all from the ground up, aimed at law enforcement and first responders and in development for the last two years.  Will it be available to the public?  Grant Chapman, Systems Engineer of the Spīr (pronounced “spire”) team, told us: “… we will happily sell to an individual that wants something this high in performance and quality .” Chapman also told us they are as much working on the tech innovations as the bike itself: “We are also looking to license the tech towards OEM bike makers looking for a high quality mid drive kit that are really good at making bikes but want don’t have the team to do the EV side of it.”

That certainly makes some sense, once you look at some of the design features – for one thing, their own controller with special sauce: “…senseless, brushless, field oriented control (torque control)”.

Battery cluster

Battery cluster

Mid-drive motor assembly, in-frame battery pack and controller

Mid-drive motor assembly, in-frame battery pack and controller

Specs?  Do we ever let you down?

Spīr inDrive Specifications

  • Battery capacity: 800Wh
  • Power: 750W
  • Torque: 100Nm
  • Weight (drivetrain components only): 16lbs
  • Drive: Seamless Integration Gearbox

Now, some of the names on the site may ring a bell – Chapman and Drew Westrick (CTO) hail from Purdue’s EV team, and were involved in the Purdue Land Speed bike we know and love.  Involved, meaning, they did the drivetrain.  These two madmen also are responsible for G-Zero Racing, urban-based electric cart racing on steroids.

The Spīr site is here, and their Facebook page is here.

Spir cutaway

Spīr tech cutaway


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29 Comments on "Spīr Bikes Launches, Targets First Responders (Exclusive)"

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This looks a lot like the natural evolution of the old “Vivax Assist” system that was designed to retro-fit into the seat tube of existing bikes:


The drawback I saw in the Vivax Assist system was that it appeared to force the pedals to turn all the time it was under power. That seemed like it could be a problem if the rider needed to have the pedals level for stability. But I never rode one so I don’t really know how it actually works in the real world. But I wonder if the Spir gets around this somehow?

Nix, likely they’ll use the pedals as a replacement for throttle input. The picture has a poor angle, but I don’t even see a throttle.

PAS works either by torque sensing, or sensing pedal movement, and using a variable multiplier to augment user provided power with the battery/motor. Those batteries and motor will be directly controlled by the rider’s feet, there’s no need to bother with a throttle.

Ah! New info! Thank you. Were you able to get onto their website? I keep getting a prompt for a password to login when I try the link.

PAS (Pedal Assist System) would definitely make it very different than the old Vivax system, which uses a push button.

I’d be extremely surprised if there’s no throttle at all. Pedelecs in those countries where they’re the only legal e-bike require pedaling for regulatory reasons more than anything else (extra cost/complexity of a throttle is very low) — it’s to force the e-bike to be usable with small 250W motors, since it can be assumed the rider is also pedaling, and to avoid making it easy for people to turn them into de-facto motorcycles (if a cop sees you riding without pedaling, s/he knows you have an illegal e-bike).
Since this bike is intended for cops, EMTs, etc., that reasoning doesn’t apply, and having to pedal might be cumbersome for cops or firefighters wearing heavy gear (boots, protective clothing / armour etc.)

That’s a nice looking bike. I’d get one but I bet the thing is pricey as heck.

750 watts of power on this bike!
That would be a very fast one.

+1 They had me at “750W”. Unless the speed is governed, this could break 30mph.

Elegant, too

That’s too much power for a bike. The battery size and the weight look good, though.

Given that it’s target market is first responders, I don’t think that is too much power at all. Remember, as the article points out, these guys are hauling 70 lbs of gear. That’s a lot of weight to be hauling when you need to get to an emergency fast. The 750 Watts will help, especially in hilly terrain.

“Weight (drivetrain components only): 16lbs”

I see they took a page from Tesla marketing. It sounds a little bit like advertising power capacity, while not addressing the system level people actually care about.

C’mon fellas. What’s it weigh, for that 90 degree “brick” climb 😉

As long as you have battery power, weight doesn’t impact an electric bike’s climbing ability as much as the weight of a regular bike does.

The extra weight can impact handling and braking more than it impacts slow speed climbing.

In fact, you don’t have to weight weenie an electric bike the same way some folks weight weenie normal pedal bikes. When it comes to climbing, the electric assist is more than enough to overcome the weight difference between having something like SLX vs. XTR Race on a mountain bike.

16 lbs + 25 lbs hardtail puts you at around 40lbs, which is very competitive for weight in the electric bike world.

I doubt the bike will be anywhere near 25lbs for the non-drivetrain parts. “Normal” e-bikes already have beefed up frames, brakes, wheels and sometimes gearset/chains, ot dela with higher speeds and the consequent higher stresses.

This is likely designed for 30mph, and rider weight+70lbs of gear… Most current prebuilt e-bikes are limited to 220-240lbs total carrying capacity (rider+luggage); this is likely 300+ lbs.

Is this bike a pedelec?

That’s really a great design. It’s solid and has the weight in a great location.

I have a nice ebike with an electric rear hub. and a nice slide in aluminum case Li po next to the down tube under my seat.

They call it a mountain bike but no way. The battery flops all over. Never had my “electric mountain bike” off the streets.

I love this solution. These batteries won’t flop around.

And it’s look like a sproket strap instead of a chain.
Will be quiet, hope it’s a strong strap with that power.

good point I missed that.

Limit the speed to 10 or 20 km/h

Hey everyone. My name is Drew Westrick. I’m one of the drivetrain engineers at Spīr Bikes. Just wanted to answer a few questions and clarify a few details on the system. The drivetrain is designed to be pedelec (aka no handle bar throttle). We have a patent pending torque sensor that is built directly into the gearbox and senses crank torque wirelessly (no batteries to replace). It is able to sense torque from either the right or left side cranks and is incredibly responsive. We are able to detect even the slightest changes in rider torque which means that the motor feels more like an extension of you rather than a delayed shove from behind. Both the motor and rider are connected to the output via one way clutches. This means that the motor can spin without moving the pedals and the pedals can spin without turning the motor. Feel free to ask me any questions you may have about the system. I’ll check back here periodically throughout the day and try and answer them the best I can.

Thanks Drew!

What the estimated MSRP?

What is the max assisted speed and is there a limiter?

Hats of to some very impressive engineering!

I think it’s important for first responders to get something like this bike. As roads become more clogged and congested, it will be difficult for emergency vehicles to get to emergencies in a timely fashion. This will help significantly.

The max assisted speed will really depend upon which class we and our bike OEM partners want the bikes to fall into. Check out the link below at ElectricBikeReview.com for more information on eBike classes. Generally our system can fall into either Class 1, 3, or 4. Classes 1 and 3 would mean that the bike could be used on regular roadways without additional licencing here in the US. Class 1 has a max motor assisted speed of 20 mph and Class 3 has a max motor assisted speed of 28 mph. In both of these classes the user can pedal the bike faster than that, but we are just restricted to those speeds when providing motor assist. To get the true full speed out of our drivetrain we would need to be Class 4 which would mean without proper licencing (like a motorcycle license) you would be restricted to off-road use only. I can tell you from a performance standpoint the drivetrain should have no problem reaching 35 mph. Sorry for making this answer so long its just the regulations really play into the speed restrictions.


I take it you’re not ready to reveal pricing yet, but can we get a general range, like $3k – $7k? That’s my best guess anyway.

Hi Drew,

Thanks for the info. I had seen a few e-Bike models recently that used to have 20 mph limits now with 28 mph limits and wondered why. Now I know, thanks!

Would a full suspension version be feasible or does your design make that difficult?

Hi Drew,

I sent you a message through Facebook as the website looks like it is currently just a place holder and there is some info I am trying to pass to you so please check your Facebook messages.



Hi Drew… how will this be sold or made available in non-first responder versions? On the website it says you can buy it or OEM the drivetrain but there are no other links.

Looks like this would be a good commuting platform

Hi all. I just wanted to answer a few more questions. The price for the complete bike should be between 5k and 6k depending upon options. We will be making the bike available in a consumer version as well. We are currently finishing up testing and validation of the bike. We hope to be in full production by the middle of next year.


At Interbike PerAm introduced the PerAm Never-Flat Bike Tube. The reception from OEM’s and wholesalers was very promising. Bike retailers – some 400 told the industry – look at this – it works.

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You may be interested in discussing a one-in-one test – We would welcome your advice.


Lee – President
Peram LLC
1318 Lititz pike
Lancaster PA 17601