Qulbix Raptor, Offroad Hot Rod Electric Bike

March 2, 2014

The Qulbix Raptor is a high-performance E-bike frame that is made to allow a very large battery pack, and a very high-powered rear hub-motor. We’ve been wanting to write about the Raptor for some time, and since they just recently changed their company name from Torque to Qulbix, that makes this month a good time to finally delve into the details.

Note: the “Qulbix” name was developed to have something that is very different than any other name out there. Many companies have “Torque” in their name, and customer internet searches were cluttered with links that have nothing to do with this awesome E-bike. The proper pronunciation is “Cool Bikes“.

Several of our featured custom builds have shown that in order to get high power from a hub motor you need two things. First, you definitely want the highest volts you can fit into the frame, and second…you need the biggest hub you can fit into the frame because a smaller hub cannot accept as many amps as a larger one.

The majority of the heat that can kill a motor is from high amps, so…the bigger the hub, the bigger the amps you can use without a motor meltdown. And when you manage to acquire an extra big hub…it reveals another problem for anyone who wants a high-powered E-bike. A large hub motor using high amps might not fit on some bicycle frames, and even if it does fit…a high-powered hub can break a stock bicycle swingarm. If you add dual or quad torque-arms to make the connection stronger, it might not allow a large hub to fit onto the dropouts on a common bicycle swingarms with a 135mm wide drop-out width.

The Qulbix Raptor answers all of these concerns, so…if this sounds like something that you might like, read on.


This company was started by an engineer who developed products for motorcycles. Then, in 2006 he formed the Torque company, and in the beginning of 2013, they produced the Torque FR1 electric off-road motorcycle. Almost immediately, some customers asked if they would ever consider making an electric bicycle with pedals for off-road.



The FR1


The Qulbix company already had a lot of experience with motorcycles, and this is why their first electric off-road “Raptor” E-bike has gotten so many things right their first time out. One of the first questions that often come up in conversation is “how much does it weigh?”. If you want your Raptor to be as nimble as possible, you can use a smaller battery, bicycle tires, and the HT3525 hub motor to get the weight down below 80-lbs (36 kg), and…if you use an extra long-range battery with motorcycle tires and a powerful cromotor, then your Raptor can be heavier than 120-lbs (55 kg).



The most important feature of the Qulbix Raptor that I want to talk about first is the incredible battery volume in the central part of the frame. This is the outstanding characteristic that sets this E-bike apart from other similar competitors. The interior width of the frame compartment is 160mm, and this is enough to set the common Lithium Polymer (LiPo) battery packs sideways in the compartment.



No matter what battery chemistry you choose, the Raptor allows the highest volts and Amp-Hours due to its incredibly large battery compartment.


The hollow frame of the Stealth Bomber is 125mm wide, the Greyborg is 110mm, and the Phasor is 100mm. So those E-bikes might be easier to pedal, but when you want the absolute highest volts along with the longest possible range (by adding amp-hours of battery volume), the Raptor has the biggest battery volume by a large margin. In this rider quote below he’s recommending a lithium polymer (LiPo) pack of 74V / 25-Ah.

“…I discovered that ideally you should have 18S / 5P. Or fifteen of the 6S / 5000-mAh packs. If you are off-roading this will give you enough power to the point you are exhausted. 18S / 3P is simply not enough range. At 18S / 4P I was still wishing for more range. 18S / 5P seems pretty perfect [and more than this would be un-necessarily heavy]…”

carsonwen: “…I am using 5S / 4000-mAh cells. I can fit up to 42 packs, Potentially 30S / 28-Ah [124V]…”



Although the frame is noticeably wide, it can still be pedaled.



The Raptors swingarm has a 150mm wide drop-out width, and spacers are included if you are using a standard motor with the common 135mm axle-shoulder width found on bicycle axles and smaller hub motors. All four of the motors listed below allow for you to use a disc brake on the rear.

The Crystalyte HT3525 is the smallest hub I’d consider on this excellent frame, anything smaller and you’d be wasting the capabilities of this well-engineered high-performance E-bike. This would be the hub you’d want if you’d like to keep a 7-speed gear-cluster, and you also want your Raptor to be as light as possible. The HT3525 has been used at 100V X 40A = 4,000W, with the side-plates ventilated to let excess heat out, and of course, adding a temperature sensor.

The next bigger motor that looks like it would work well is the Crystalyte 4080, which can accept a 5-speed gear cluster. The 40mm wide stator (5mm wider) allows it to take a few more amps than the HT3525. The H4080 also has a common 135mm drop-out width.

Next up is another motor from Crystalyte, “The Crown” motor (TC80), it uses the same 40mm stator width as the H4080, but it can take more amps due to two improvements. The Crown has a thick aluminum core (as opposed to the H4080 steel stamped core) that will absorb temporary  amp heat-spikes to help stabilize the internal temperatures. And second, the stator teeth have deeper slots to allow for a slightly higher copper fill. More copper = more amps. The one drawback of the Crown over the H4080 is that the Crown only allows a single-speed freewheel. The Crown has a 140mm drop-out width.

The most popular motor for the Raptor is the Cromotor from Zelena Vozila, (right next door in Croatia). Be aware that he drop-out width of the North-American spec Cromotor is 145mm, and the Euro-spec Cromotor has a 155mm drop-out width. And you will definitely only fit a single-speed freewheel on the Cromotor. All of these concessions are so the builder can have the Cro’s massive 50mm wide stator. This wide copper mass means you can feed your Raptor the maximum possible amps for brutal acceleration.

offroader: “…The Cromotor V2 is amazingly smooth and quiet..”



So far, the two most popular controllers have been the Lyen 18-FET, and the Kelley KHB.

The 18-FET may not seem big enough, but if you are running your Raptor at 24S / 100V, then 60A from an 18-FET should be more than enough. The standard mounting location for the controller is the front of the down-tube, and the 24-FET size will fit if you want more than 60A

The original Raptors’ protective cover for the controller was not wide enough for the Kelly KHB controller (204 X 162 X 84mm), but the most recent version has been widened slightly to allow for this well-regarded option.

“…I adjusted the power on my Lyen 18-FET to 130 phase amps, 60 battery amps at 72V and WOW, amazing power. This bike is the ultimate urban assault bike and it makes beating it around an urban environment a whole new fun thing to do with an ebike….”



Here is the (red) 253mm-long vented steel bash-guard for the front-mounted controller.



I haven’t had the opportunity to ride a Raptor yet, so the following advice is from the very experienced ES members “Rix”, “snellemin”, “offroader”, and “moonshine”:

The rear shock has a movable mount (with three possible positions) to allow you to choose from a variety of options. It can accept a shock length from 8.5-inches to 10.5 inches long (216mm-267mm)

1. For serious off-road riding I would recommend 267 X 89mm (10,5 X 3,5”) rear shock, mounted on the top bracket holes (wheel travel: 260mm, BB height: 360 mm, seat height: 910 mm).

2. Second option for milder off-road is to use 240 X 76mm (9,5 X 3”) shock (wheel travel: 230mm, BB height: 330 mm, seat height: 880 mm) – this one should be mounted on the middle holes.

3. The lowest holes are suitable for 216 X 63mm or 222 X 70mm shock, This one is suitable mainly for city and street cruises (wheel travel: 190mm, BB height: 290 mm, seat height: 840 mm).

“…If you go with a Fox DHX RC4 10.5 X 3.5 then I recommend a 400lbs spring weight if you weigh 130lbs to 180lbs. I bottom out often with a 350lbs spring and I weigh 135lbs, although the 350lbs does work well. A 450lbs spring was way too stiff and I could never use all the travel or even close to it, so I think a 400lbs spring would be perfect for the average weight rider…”

“…I would get the bike with a 10.5 X 3.5 rear shock and not the 9.5 X 3.00. The bike can handle the longer travel so, why not use it? You may however want to consider a 9.5 X 3.00 if you are really short (or using a 24″ tire up front) as you can’t adjust this shock using the bikes bolt holes to lower the height. The 10.5 X 3.5 and 26″ tire up front will give you a 14″ bottom bracket height [for great ground clearance], which is optimal…”


If you don’t have a preference, here are two proven options: “…I personally went with a Marzocchi 888 RC3 EVO V2 because it uses an oil bath and I heard it would require a lot less maintainence than a Fox 40 Float 26. Since I am not big into doing maintenance, I went with something that I wouldn’t have to service very often. However, the head tube on the raptor is just slightly too long to fit the Marzocchi upper crown flush (sticks up about 10% over stanchions), but it is workable and fixable…”

“…[I use an] Rockshox RS Boxxer with 200mm of travel…”

“…If you haven’t tried one of these DNM USD-8 forks, they ride super smooth. I LOVE this forkin thing…These are an improved version of the older Volcano fork, these now have 8″ of travel, an extra inch more than the previous version…”



This Raptor is from ES member “moonshine



The swingarm is designed to accept tires as fat as 3-inches, and although some riders will use fat bicycle tires, there are several motorcycle tires that work well with the Raptor because of this extra tire space.

“…I have now tested 16 different tires. I keep going back to the Shinko SR 241 because they are the best on both the road and dirt. A knobbie works better on the dirt, and the M62 Michelin works better on pavement. But no tire works better than the SR241 on all types of terrain….That is the best tire I have tested to date in sizes 2.75 X 19, 3.00 X 17, and 2.75 X 17…”

“…I went with the Prowheel rim and Shinko 241 tires. The Raptor needs a 26″ front wheel to maintain the 14″ bottom bracket height, the rear can use a smaller diameter tire and be adjusted for higher height with the movable shock mount. If you had a 10.5″ shock and a 26″ rear wheel it would probably raise the rear too high (and couldn’t adjust it anymore to lower the height), so a 10.5 shock and 19″ Prowheel is perfect setup. Plus you get over 10 inches of rear travel with a nice long 10.5 X 3.5 shock…”


The Cromotor with Shinko SR241 tires.

The Cromotor with Shinko SR 241 tires.


“…I also feel that putting a dirtbike tire in the front is questionable. Maybe it could be better but I have my doubts. For one, the downhill biking community does not like big fat 3” tires out front. With the better suspension, there is no need to use such fat tires. Supposedly you want the front tire to not be so fat so that it can dig in better in off-road conditions…”

“…There is also no reason to use a heavy dirtbike tire and wheel on the front when a bicycle tires will give you far better selection, and weigh much less. Bicycle tires I find work well on the front, and never pinch flat and also wear very slowly. I would think a bicycle tire also has softer compound and will be better suited for a much lighter ebike than a motorcycle. This is only for front tires, for the rear…a dirt-bike tire is a must! You should really only use a 19″ prowheel rim in the rear…”

“…After the big problems with bicycle rear tires pinch-flatting all the time and wearing away too quickly, the Shinko 241 is a dream tire. Both the 241 Shinko 19 X 2.75 (and Duro Razorback 26 X 2.6 front tire) have held up really well to constant abuse. I am talking about hitting curbs and steps at high speeds, and doing high jumps! If you insist on using small spokes, go 12-Ga minimum. High quality 12-Ga will be adequate, but 8-Ga to 10-Ga is better, though…”

“…The reason I recommend a 26″ mountain bike up front is first it seems to be accepted amongst downhillers that 26″ wheels roll better through obstacles than 24″ wheels. You will also have many more tire options in a 26″ size. Other reasons are that a motorcycle tire up front will probably have too stiff of a tread for optimal traction. You will also have added weight which is not needed, and the fact is the front tire on an ebike doesn’t wear away quickly and doesn’t have any problems with pinch flats. There is no reason to use a heavier tire and rim which may throw off the fork performance with the extra weight that it was never designed for. I know a Stealth uses 24″ tires up front, but that doesn’t really seem to make sense why they choose that…”



Here is a Raptor with a Cromotor, sold in Europe by eRIDE Horizon from Austria. The tires are Maxxis Creepy Crawler’s



“…The Shimano Zee hydraulic brakes are highly recommended, they simply have amazing power and only need one finger to stop the bike. They also received great reviews for the price, and are pretty much the same as the Shimano Saints (which cost much more).

If using Shimano rotors make sure to get a SM-RT66 203mm in the rear, since ice tech’s or xt’s will not sit flush with the Cromotor-V2 and the spacing will be off. For the front disc, you can use whatever one you want…”

Uschi K: “…[I use the] Gatorbrake 8 piston…”


Motocross style seat, or bicycle seat?

There are two seat options, and if you buy both, they are easy to swap between them. If you choose a bicycle seat, the diameter of the seat-tube will accept a 30.9mm post.

The common bicycle seat post is self-explanatory, but the highly recommended option is the motocross-style seat. It sits low, so shorter riders may end up needing this, regardless of preference. And even if you are tall enough to use the bicycle seat, the MX style can be squeezed between a riders thighs at high speed to more firmly anchor the rider to the bike.

One rider is quoted as saying: “I actually sat on my old cross-country E-bike today and can’t believe I used that bike for so long with that uncomfortable hard bicycle seat. It brought back memories of it constantly whacking my ass as I drove that bike hard off-road over bumps”



Here is the optional motocross-style seat. The tires here are the Scwalbe “Crazy Bob” model, for cornering well on the street.



Most North American riders may not realize it, but motocross (MOTOrcycle-CROSS country), started in Europe many decades ago. So, European countries have a long history of expertise in this style of off-roader…and the Slovenian-based Qulbix company (between Italy and Greece) is no exception.

Here’s a video of a Raptor climbing stairs.

The following quotes from ES members “Rix”, “snellemin”, “moonshine”, and “offroader”:

“…The Raptor is ridiculously stable at high speed…”

“…My bike accelerates really quickly to 40-MPH and I’m liking the longer wheelbase vs my other bikes, I had 40-MPH max in my head when I decided to build a Raptor. But was quite surprised that I can hit 50-MPH on only 21S LiPo [86V]. It’s nice to commute with to work. I have enough power/torque to stay up with traffic, and avoid road rage…”

“…It is a dream having the batteries weight enclosed in the center, and not worrying about damaging them. I’m using fifteen 6S / 5000-mAh Turnigy packs, and will increase it to 24 packs (and possibly 28 packs) to get more range. The Raptor really shines in that it can be used with a lot of batteries, so make sure that you take advantage of that. You can probably fit about 3-times the amount of batteries in a Raptor vs a Stealth bike…”

“…The geometry is exactly how I wanted it with a 26″ front bicycle tire and 19″ dirt bike tire in the rear, when using a 10.5″ stroke shock. The bike just handles amazing….”


From Ziva: “I can say that we have sold Raptor frame kits to Australia, Germany, UK, Belgium, Canada, Portugal, USA, Russia, Estonia, Belgium, Austria, United Arab Emirates, France, Israel, and Spain!…we think this industry has a great potential to evolve. And it will evolve to incredible proportions, I am sure. Electric bikes simply have it all: they are fun, useful, and they fit right into our vision of sustainable society…”

Ziva: “…And another thing: we are preparing a new complete Raptor E-bike [instead of just the frame], and I will let you know as soon as it’s set to go….”


Here is the Qulbix website homepage.

Here is the Qulbix Facebook page.

And finally, here is the 36-page endless-sphere forum discussion.


Written by Ron/Spinningmagnets, March 2014


Grew up in Los Angeles California, US Navy submarine mechanic from 1977-81/SanDiego. Hydraulic mechanic in the 1980's/Los Angeles. Heavy equipment operator in the 1990's/traveled to various locations. Dump truck driver in the 2000's/SW Utah. Currently a water plant operator since 2010/NW Kansas


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