- For the DIY builder who wants a full suspension electric bike perfectly suited for hard core mountain e-bike riding and able to hold enough batteries inside the frame to give you a real 40 mile range, and able to handle a hub motor large enough that could easily give you a 40mph+ top speed… if you ever wanted to own such an e-bike with the added benefit of the frame being professionally designed and then hand built by a talented young American mechanical engineering graduate, right now is your chance. The Phasor Cycles is one of the best values for a high performance full suspension electric bike on the market right now if you are willing to build it yourself. And by buying one you could be helping kick-start a newly found American industry, the high end electric bike market (the low end is dominated by low performance chinese-made e-bikes). In the last few years the electric components needed to build an e-bike have evolved greatly thanks to the millions of electric bikes built in China and a lot of DIY e-bike tinkers have been taking advantage. The problem that the e-bike DIY builder faces is that although there are plenty of good chinese hub motor, battery and controller choices, the specialized e-bike frames coming out of China have not been very good or stylish and it is too difficult and expensive for most DIY builders to consider building their own frame from scratch. Therefore what we have seen in the DIY e-bike community is builders converting bikes that were designed to be bikes. This is fine, but where do you put the battery if your intention is to ride more than 10 miles? The result has been a bunch of unrefined frankenstein bikes that shake and rattle and are not very well balanced. Oftentimes they contain lipo hobby king packs that are not in a metal box contained in the frame and can be a fire hazard. Riding these kinds of bikes offroad in bumpy conditions compounds this problem. Most DIY bikes either use rear racks with soft bags or soft pouches of some kind in the frame’s triangle to hold the battery which will not contain a lipo fire. The threat of lipo fire is not greatest when out riding the e-bike on the open trail but when the electric bike is parked inside a house or a garage charging unattended…well, you can imagine the consequences.
David Pearce and his creation the Phasor Cycle
Most e-bike manufacturers in the United States have resorted to converting existing bicycles rather than going through the expense and difficulty of building their own frame. The Phasor on the other hand is much more that a converted bicycle. Phasor Cycles is a new electric vehicle company started by two people on a shoe string university grant and is one of the few American companies attempting to build an e-bike from the ground up. The big difference between this e-bike frame and a converted e-bike frame is that the batteries are mounted snugly in the frame in a purpose built metal enclosure. This not only makes the bike fire safe but also more stable, robust and balanced for hard core off-road riding. Also this e-bike has a slick look, a rarity amongst thousands of commercially available cheap e-bikes pouring in from China.
By the way, pictures sent from David’s garage work shop prove that this bike is exquisitely hand made in the USA – a rare thing these days but as you can see, this is not your typical “garage build”.
welded frame in jig
Raw Phasor Cycle #1
- Phasor Cycle frame just back from paint shop
David is selling the bike frame pictured above, powder coated and finished in color of buyer’s choice, including all custom frame components, bearings and extra wide bottom bracket spindle but without the rear suspension, crank set or pedals for $1,860.00
The workmanship and attention to detail on this frame cannot be stated in just words. A lot of skilled hand machined artistry goes into this bike. To give you an idea, check out this video of what goes into just building a swing arm for this e-bike:
The big drawback of the Phasor e-bike for most consumers is that you will be required to source and buy all the components yourself, assemble the bike, design your own battery pack and wire all the electrics. If you tried to buy all the bicycle components necessary to complete the Phasor at your local bicyle shop, it would cost you a small fortune. Thankfully, Google and internet shopping sources to make this somewhat easier and cheaper for a bargain motivated shopper. But for sure sourcing components for this bike will be a time consuming and potentially expensive task if you do not shop wisely. Expect to spend many hours researching which suspension fork to use etc. And we haven’t even considered electric components yet (battery, motor, controller) which is a headache in itself. The Phasor is essentially a DIY electric bike builders dream, but could be a nightmare for a novice who is just getting into electric bikes and wants something to ride asap. David says that in the future the Phasor company will offer customers to build their bikes with the components of their choice. We hope that Phasor Cycles will at least provide some kind of a list of suppliers showing where to buy each component that will be needed.
As far as components costs, the bike I tested and rode with – bmc motor 20amp 56 volt battery pack, bmc v3 motor, high quality fox shocks front and rear, David estimates that it would cost $6,000.00 to build with the price of the frame included. Lots of money can be saved by buying lesser components (David uses a top of the line fox 40 rc2 front fork and dhx rear shock). You can save even more money by finding a used downhill mountain bike through Craigslist or Ebay and stripping the components off of it. These days it is not hard to find a top of the line used downhill bike for $1,500.00 and a decent one for $500.00 When you get into the project, you will find many ways you can save money – less battery, cheaper motor etc. and you can decide for yourself if and how to cut corners. This is a great way to learn firsthand why the e-bike equation is so complex and why it is hard to find a high performance, relatively light weight e-bike with a long range at a cheap price.
The other big drawback to the Phasor e-bike is that there is a lead time. Currently, the wait for your frame to be delivered is up to three months after putting up a 50% deposit. That’s a long time to wait for anything in this day and age.
Lets look at some of the features and specifications of the frame itself:
Features / Specs:
- Fully TIG welded Chromoly frame and monopivot swingarm
- Front suspension compatibility Uses standard MTB 1.125″ steerer tube
- Clearance for long suspension travel, 26″ wheels (up to 28″ actual tire OD)
- Large enclosure, room for lots of batteries, controllers(s), chargers, wiring, etc.
- Progressive rear suspension geometry
- High ground clearance
- Low, centralized center of gravity
- Zero offset rear- no dish required
- 66° Head tube angle
- 50″ Wheelbase
- Standover height ~ 31″ with 8″ travel forks
- Thick 3/8″ 4130 chromoly dropouts with captive axle retainers
In general this bike has an aggressive stance, like a downhill mountain bike with high forks and low seat. It is designed for stability riding in off-road conditions, and for making big jumps. The bike can handle a pounding as can seen in the video at the bottom of this story.
Now lets look at the specifications of the compete e-bike as tested:
- 20A*hr, 56V Zippy LiPo (15s4p)
- BMC Geared hub motor
- 40A e-bike motor controller
- 26″ x 3″ wheels with 2.7″ Kenda Nevegal tires
- BMC V4T hub motor
- Hayes hydraulic disc brakes, 9″ front 8″ rear
- Weight: 85 lb as shown
- Fox 40 RC2 8″ travel downhill forks
- Rear shock Fox DHX 3″ stroke coilover – with 2.7:1 leverage ratio for 8.1″ rear travel 9.5″ eye to eye
- Cycle analyst
Some explanation is order in terms of the electrical components that David chose. Remember that this bike can be configured in any way that the builder chooses, so all his choices might not be your choices.
Battery:
20ah of 56 volt battery is a lot of lithium. This is more than twice as much battery as you will find in any available commercial bike. Lithium battery is generally the most expensive component of an e-bike. This e-bike with 20ah of 56 volt is over 1000wh of battery. To give you an idea the Specialized Turbo comes with 350wh of lithium and the bike cost over $7000. The $12,000 optibike has 720wh of battery. The $5000 Smart e-bike comes with 400wh of battery etc.. However all those mentioned bikes come with professionally assembled battery packs with battery managment systems, and are considered completely fire safe. David’s bike was designed to fit hobby king cells and a DIY battery assembled by the DIY buyer so the risk is in the users hands, even though the risk is lessened because of the metal battery enclosure. Assembling the battery pack would be the hardest part a first time DIYer would face building a Phaser, and should not be taken lightly. According to David, the Phasor is capable of holding double of what he has in it as tested, or up to 40ah 56 volts, over 2,200wh. Remember this would add to the cost and the weight of the bike significantly. An extra 20ah 56 volt of hobby king lipo would weigh around 18 extra pounds, and cost somewhere around $650 to build not including a battery management system (bms) which would be a realy good idea considering the size of pack. Please look to the forums at endless sphere if you are looking to take on building a lipo pack for the first time, and do all the research you can on that forum since building a lipo pack is a difficult and possibly a dangerous undertaking. For a primer on selecting a battery read our article here:
bmc v3 hub motor
Motor
Phasor cycles have been designed for a rear hub motor. It could be run with a front hub motor, although traction is a problem when climbing steep off-road terrain with only a front hub set up. If you were an extremist you could run a hub motor on both wheels for all wheel drive (see our article on choosing front or back hub motor )
The BMC is a geared hub motor weighing only 7.5 pounds and putting out more power more efficiently than a direct drive hub motor. See our comparison by clicking here. The BMC uses a planetary gear system, making it much more efficient and lighter weight than a direct drive motor which has no gears. However the BMC is not able to handle the huge powerloads of a direct drive motor, so has a maximum speed of around 40mph depending on how it is configured…but at any speed above 30mph the user must be careful not to overheat and fry the motor. The bmc v3 as tested on this bike is a $400 motor. It is among the most refined hub motors on the market, however because of its complicated nature (having gears) it is less reliable than other high performance hub motors on the market (which are heavier). If you can accept a lot of extra weight and drag in the rear wheel, many users will opt to go for a much larger and more powerful direct drive (gearless) hub motor, for example the Crystalite 5304, the same hub motor used in the Stealth Bomber which could easily transform the Phaser into a 50mph machine but weighs in at a heft 25lbs…a lot of weight to have unsuspended in the rear wheel.
Cycle Analyst V2
Cycle analyst-
David uses a Cycle Analyst by www.e-bike.ca to contantly guage the usage of his batteries and to make sure he does not damage his batteries by going beyond their safe voltage point. He is also able to tell how many amp hours he has used, so while out trail riding he doesnt run out of battery and end up pedalling his heavy best home. A cycle analyst has become a staple to DIY e-bike builders and is essential to anyone using a built yourself lipo pack, especially if that pack does not contain a battery managment system. These days most high performance e-bikes are equipped with cycle analaysts, even many of the factory built high performance e-bikes such as the Stealth Bomber.
3 inch phasor cycles compared to 4 inch Surly Pugsley tires
Wheels and tires
The Phasor has room for massively wide tires. The bike we tesed had 3 inch wide rims, but there was clearance for even wider rims….maybe even 4 inch fat bike rims. This bike tracks really well with the extra wide 3 inch rims. The extra width made a huge difference in the stability of the bike when I test rode it on off-road trails. We at electricbike.com believe in wide tires on electric bikes. See our article on tires by clicking here:
Brakes
This bike uses high quality bicycle hydraulic brakes with giant rotors. Quality brakes are essential on a bike this powerful, especially considering its weight and capacity to bomb down hill. Look at our article here on importance of brakes:
example of wiring of the Phasor Cycle
Wiring
This is a small detail that makes a huge difference. But most DIY bikes have exposed wires running across the frame that are very unsightly. Wiring is one of the ugliest features of DIY electric bike and on a conversion bike is a hard problem to solve. On the Phasor e-bike, the wires are well hidden and protected within the frame. Same with the gigantic battery which is also hidden within the frame. Because the Phasor Cycle frame is essentially a hollow shell you are able to run wires within the frame and pop them out wherever you desire (with the help of a drill).
Ride Report
I met David for 15 mile ride through Del Cerro Park, a popular Southern California mountain bike destination on the coastline in Palos Verdes. I must say it was a nice change of pace to be riding on an e-bike where the battery was so large that getting stranded out on the trail was almost a non issue. With the type of riding we were doing the Phasor had a 25 mile range, even though we were riding with a lot of acceleration and speed up and down hills, the type of riding that is not efficient for electrical systems. Having a battery built into the frame so that you dont have to change packs when one pack runs out etc, was a real nicety, and there are only a few high performance bikes I have ridden (Steath Bomber, Optibike) that I had this sensation that I would tire of riding before the bike ran out of battery.
In the last few years I have ridden many DIY full suspension mountain e-bikes and have never been that impressed when it comes to trail riding because of the awkwardly mounted battery pack. When riding the Phasor the feel of the low mounted battery had a really nice effect. The only ohter time I have felt this is when riding an expensive Optibike or Stealth Bomber. The weight of the battery becomes a keel that actually makes the bike feel more stable, like a mx motorycle, rather than a wobbly e-bike with weight mounted up high that I am more use to. The Phasor makes mountain trail riding fun, quiet and smooth…a rare sensation atleast in my experience of e-bike trail riding.
The other big factor of having the batteries mounted inside the frame is I did not feel the jankiness I usually feel when riding a DIY mountain bike with battery on the rear rack. No rattling noises or worst, the sound of big dangerous bricks thumping around when I go over jumps. As you can see in the below video, this bike can actually take gigantic jumps, and still nothing on the bike makes clunky noises except for the tires hitting the ground and the suspension compressing.
So although I was riding an electric bike component wise (both suspension, and electrical) very similiar to conversion e-bikes I own and have ridden, because of the purpose built e-bike frame, this bike made for an entirely different kind of experience than what I am used to. The bike handled solid, and I found myself riding faster on a rough trail than I usually would. For better or for worse the Phasor inspires confidence when riding fast off-road and tempts you to ride faster. The only other electric bikeI have ridden with this kind of stability and solid feeling when riding off-road and this kind of power (the Optibike lacked power) is the Stealth Bomber:
Phasor Pros vs Bomber
- Considerably cheaper to build bike of similar performance
- Versatility in what components you use on bike
- No choice to opt out of the expensive and heavy V-boxx (7.5lbs)
- option to use high density lipo batteries
- Easily can be repaired by replacing components that fail
- Owner learns bike inside and out by assembling it
- Owner can choose any color for frame
- American Made help the USA
- No expensive shipping from overseas
- Do not to deal with an expensive and complicated v-boxx repair in case it fails
- Extremely Rare/special bike
Phaser Cons Vs Bomber
- Have to source components and assemble bike
- no company support like Bomber offers.
- No warranty on components like Bomber offers
- Have to assemble your own battery pack
- Potential lipo fire danger
- no community of Phasor owners like Stealth google group
- unproven frame design compared to Bomber
- Does not have the straight chain line the bomber has.
Read our ride report and review of Stealth Bomber Here.
The Stealth Bomber and Phasor bikes are very similar looking machines, although you can tell by examining pictures that the Phasor is not a clone type rip off of the Stealth Bomber. The phasor is completely different geometry wise and uses a different type swing arm .The idea of the bikes is the same, a fully suspended rear hub powered bike designed for off-road riding that can carry a lot of battery…so naturally they do share design characteristics.
The Stealth Bomber is custom built around a fancy pedal gearing system called the suntour v-boxx. The 9 speed v-boxx is very unique and you can’t opt out of it if it happens to break. Since it is very rare, you will have a very hard time replacing it or repairing it if it does fail. The v-boxx also has the disadvantage of being heavy. At 7.5lbs the v-boxx system weighs as much as the bmc motor David is running on his Phasor. However the benefit of the system is you get all your gearing inside the bottom bracket so you have a perfectly straight chain line without derailleurs. With the Phasor, as in any hub motor bike, an internal gear hub shifting system such as an alfine 8 is out of the question. So therefore the only good choice to go with a straight chain line and without derailleurs on the Phasor would be the Schlumpf planetary crank system which would give you 2 speeds, one very high and very low. This is worthy to mention because Stealth offers a 2nd bike, the Stealth Fighter which uses the Schlump instead of the v-boxx. However, even though not as sexy as a v-boxx or schlumpf, a derailleur system makes a lot of sense because it is cheap, light weight, easy to have serviced, and easily replaceable.
I have ridden both a Phasor and a Stealth Bomber and they do indeed ride very similar. I must admit I am not a hard core trail rider and therefore cannot comment on geometry differences, trail riding characteristics etc. They both feel really solid and stable to me. Most of my e-bike riding involves riding on the road, fire roads, and mild off-road and both bikes are overkill for this type of application, but the full suspension and low mounted battery is a real luxury anyway. However for reasons stated above, if I owned a bike like the Phasor or the Stealth I would probably be more into trail riding. The big difference I see between the two bikes, is David built his bike with the 7.5lb BMC hub motor, where as the Stealth has 26 pound crystalite hub motor in its rear wheel. Also David is installing lighter and denser lipo batteries, while the Stealth Bomber has chosen to use the heavier but fire safer lifepo4. Phasor weighs in at 85 pounds. The STealth is 120 pounds. The STealth has a higher top speed and accelerates harder in payment for these extra pounds. However, the Phasor can easily be mounted with the same motor as the Stealth and have the same performance numbers, and still stay 15-20 pounds lighter than the Stealth . Stealth has thrown weight out the window with many of its component choices. For example its cheaply priced RST-R1 fork is a full 3 pounds heavier than the Fox fork david is using.
But the worst place to accumulate weight is in the wheels. Unsprung weight in the wheels is a big deal handling wise. So having either a 26 pound crystallite 5304 or a 7 pound BMC motor in your rear wheel is not a good thing but the bmc is the much lesser of two evils. The 26 pound crystalite does feel like a lead barbell when riding the Stealth Bomber. And with the Phasor you could run either motor since you build and configure the bike yourself.
Which brings us to the biggest advantage of the Stealth Bomber. For those who do not want the hassle of building their own bike, the Stealth Bomber comes in a box, turn key ready to ride. You have a company to answer your technical questions if you have any problems, and the bike even comes with a warranty alhtough shipping the 120 pound stealth to a repair center would be a big expense and a hassle to say the least. And lets not forget the price of the Stealth as the one I tested is $12,000 and can cost even more depending on the options you choose.
When you build a bike up yourself like the Phasor you willl understand how each component mounts and if anything breaks you can easily switch it out. So count easy repairs as an advantage to a DIY e-bike like the Phasor. However you will be on your own with no one to complain to, and most likely will have to eat the cost of the broken part.
Also when building and researching your build you will really learn the difficulties of the e-bike equation…for example choosing weight over performance, or weight over range….how much the battery costs, how long your battery will last etc. You will probably find once you get into it, that owning a fast e-bike with a long range that is affordable is a nearly impossible task.
David says the price to build up the Phasor e-bike as the one I rode complete with top of the line fox suspension on front and rear would run around $6,000. It could be done cheaper if you used less expensive suspension components, or even cheaper buy buying a used downhill mountain bike off craigslist or ebay (you can buy a top of the line dh bike a few years old for $2000, and a decent one for 500) and stripped it of its suspension and components and then sold the bare frame back on ebay. Or you could even go cheaper by installing less battery or a less powerful less expensive motor. But these are all compromised that would be hard to make.
The Phasor when configured correctly (expensively) is similar to the $12,000 Australian made Stealth Bomber electric bike. However this bike can be built for less than half the price of the Stealth, and since Phasor only sells the frame, the end user has a lot of versatility on which motor, battery, and suspension components to fit the bike with. However as we have stated, that versatility is also a big headache and can be expensive if you don’t research every thing carefully before you buy.
Several years ago, when David was still a college student he was asked why he chose a high performance electric bike as his senior project. He answered “When we saw that no one was really making anything with the performance we sought for at a price we could afford, we set out to make our own,”
Now, a relatively short time later, David has successfully brought a worthy contender in the world of high performance e-bikes to the commercial market at a more affordable price than anything else offered in a full suspension high performance e-bike. We at electricbikes.com wish him the best with his electric bike business venture.
For those interested in purchasing a frame, David is accepting deposits for the first production run scheduled for summer of 2012. https://www.phasorcycles.com/