CYC X1 Pro Gearing (Off Road)

Boostin22

New Member
Region
Canada
When I was building up my CYC X1 Pro Fatbike, I ran into a lot of conflicting information on gearing choices for the motor. I’ve ran the motor for a few seasons (600kms) now and have tried three different gearing combinations, so I’d like to share my experiences to try to help others make their choice.



Note – this is specifically related to an offroad / mountain / fatbike application. If the bike is going to be used primarily on-road, this may not apply to you. I am a pedal assist rider only, and only use the throttle to occasionally walk the bike up steep hills or get me started in deep snow.



CYC offers three different gearing combinations when you purchase the motor



  • 11/53 with 32 tooth bike chainring
  • 11/63 with 38 tooth bike chainring
  • 12/72 with 42 tooth bike chainring


The first number in the fraction refers to the number of teeth on the motor gear at the driveshaft and the second number refers to the number of teeth on the chainring which is bolted to the bike chainring driving the rear cassette.



For anyone familiar with bikes, the number of teeth on the bike chainring gives an indication as to what the gearing combination the motor is designed for. A 32 tooth setup will have the most torque, but lowest top speed, while a 42 tooth will be the opposite (higher top speed, worse for hills).



I’ve tried the following combinations on my Fatbike:



11/53 with 32 tooth

11/63 with 38 tooth

11/53 with 38 tooth (current setup)



In the past, I ran the 11/53 32 tooth in winter, and the 11/63 38 tooth in summer. I use the bike primarily on the trails around here, so first and foremost it must be able to climb. I severely underestimated how well a bike with 4.6” wide tires and lots of power can climb hills. Massive traction and enough power to keep your speed up is a killer combination. For mountaineering and exploring, the bike works amazingly well. Originally, I’d only intended on using this bike in winter, but have found myself really enjoying it during the summer months as well. Its Achilles heel is that wide fatbike tires don’t corner well and aren’t precise like a 2.3-2.6” wide mountain bike tire would be. Airing the fatbike tire up to 15-20 psi helps this a bunch, but it still isn’t a great downhill bike for ripping turns.



On the plus side, I can wheelie up hills over rocks and roots that I would lose momentum on with a regular mountain bike tire. I find hills for fun that I’ve never been able to climb on any other bike and keep pushing what I think I can get up. I’d seriously consider building a fatbike as an ebike build, especially if you live in a snowy place and can use it year round.



But back to gearing, I’ll outline my experiences with the three different drivetrains below:





11/53 - 32 tooth



It helps to think about the bike’s drivetrain based on how fast you want it to be able to go. Most bicycle cassettes have a smallest cog that is around 10-11 teeth. Running the 32 tooth front chainring with a 10/11 tooth rear cog, I maxed out at around 40-45kph (25-30mph). It was geared very short for longer distance riding/commuting. I did use the bike occasionally as a commuter and found myself constantly running in the smallest rear cog to go as fast as possible and being a little frustrated at the low top speed.



Since the rear gear has so few teeth and only half of them are engaged at a time, the chain has a tendency to skip and derail at high torque and cadences. (A clutched derailleur and a really good derailleur adjustment from a reputable bike shop solved these issues for the most part for me).



Although I really liked this setup on the trails, it wasn’t doing it for me on the commutes, so I decided to purchase the 11/63 with 38 tooth to try out for the next summer when I wouldn’t be on the snow.





11/63 - 38 tooth



When I first tried this gearing choice on the road, I was underwhelmed. The quick blast of torque that I enjoyed down low on the 11/53 was gone. However, this gearing was much better for commuting. The 38 tooth chainring allowed me to go faster and the motor delivered a lot more assistance at the top end to keep me at higher speeds.



If you were primarily commuting on road, or riding graded trails, I could see this being a great choice. A lighter bike with smaller tires would no doubt be quicker to speed up. I was able to get this bike to around 55kph and probably could have squeezed out about 60kph at maximum pedal speed (cadence). One thing I noticed is that my battery usage went way up with this combo. Cruising a heavy bike with wide tires at higher speeds requires alot of wattage. I noticed a significant difference in wattage used travelling at 40kph vs 50kph using the same amount of my effort. Also, due to motor gearing, the motor was spinning at a higher RPM at a given speed with this gearing choice. If you have a small battery or are going long distances, this is a factor to consider.



Personally, I really enjoyed the fast responding torque that the 11/53 setup provided, but also wanted the higher available top speed that the 38 tooth chainring in the 11/63 provided. So, I wondered if I could get the best of both worlds. Enter the 11/53 with 38 tooth bike chainring.



11/53 - 38 tooth



CYC has never officially offered this as an option, but after some thinking, I ended up swapping out parts to give it a try. And luckily for me it fit, but just barely. When you are considering a drivetrain, you have to figure out how much clearance you have between the chainrings and the chainstay of your frame. (The chainstay is the lower part of the frame that goes around the tire). I’ve attached a couple pics to show what the gearing combo looks like and how it interacts with the chainstay.

hybrid gearing CYC.jpg


hybrid gearing CYC2.jpg




CYC offers a scaled printout on their website so you can mock it up on your bike to check for clearance.



https://www.cycmotor.com/x1-pro-gen-2



For me, this combination is perfect. I get the quick response of the 11/53 motor gearing, but with the 38 tooth bike chainring, I am still able to get to get up to ~50kph when I’m trying to commute and get somewhere quick. I’ll be sticking with this combination going forward as it offers the best of both worlds for me. I’m moving to a studded 5” rear tire (Terrene Johnny 5) and my chain with a 100mm BB is going to hit the tire. Next upgrade is to install a 120mm BB (with spacers for my 100mm frame) with CYC’s upgraded freewheel to give me some more clearance to the tire.



Bicycle Cassette / Chainline Considerations:



I should mention that I run a 12 speed wide range cassette. The advantage of this is I get gearing to climb hills (50 tooth) and go fast (10 tooth). There are a couple disadvantages to this setup.



To incorporate more gears, the cassette needs to be wider. The chain has to move from the single chainring at the motor inwards and outwards to reach both sides of the cassette. The more gears you have, the more offset the chainline will become. This puts added stress on the chain and the gears in the cassette. To mitigate the risk of blowing up the drivetrain I use steel gears (Shimano Deore / SRAM NX both work) and relatively low power for the motor (1200W).



Aluminum gears are lighter and the non-ebike biking community pays big bucks to shed those grams, but for ebikes steel gears are the way to go. I also buy the best Shimano / SRAM chain available – the strength and durability difference is significant. A 12 speed chain is narrower than other chains so the extra strength is essential. See link below for more testing info.



https://cyclingtips.com/2019/12/the-best-bicycle-chain-durability-and-efficiency-tested/



The freebody hub that the cassette slides onto is also typically made out of aluminum. Steel freebody hubs are much better but harder to find. (Some OEM’s are starting to spec them in steel for use in their ebikes, but it isn’t common). Under high torque, the gears in the cassette can notch into an aluminum freebody hub, which is relatively soft. Having gears which are pinned together to share the load, a steel freebody hub, or both, will help extend the life of your drivetrain.



The last piece of the puzzle is the hub. Ratchets and pawls typical on most mountain bike hubs are weak and not meant to handle ebike levels of power. DT Swiss’s Star Ratchet system is much more durable and is the strongest option I’ve come across.





CYC Power characteristics compared to OEM e-bikes:



I’ve ridden a Specialized Turbo Levo and thought I would add some comments on the power delivery of the CYC motor compared to the Specialized. The power delivery is very different between these two bikes. The Specialized has a very strong assist at low cadences, more even than the CYC with 11/53. Where things change is at high cadences. The power delivery of the CYC reminds me of a 2 stroke motorcycle. It provides low assist when I am pedalling around technical trails, but when I speed up the cadence for a hill – watch out! It provides a steep increase in wattage at higher pedal speeds just like a 2 stroke “coming on the pipe”.



I’ve come to like this characteristic, because it lets me be very frugal with my battery consumption most of the time, and then power up climbs with ease. The Specialized has more of a natural feeling than the CYC, so I’d give it an advantage in that respect. Some of this may be due to the extra 15lb or so my bike weighs as compared to the Specialized. However, even despite the weight, the top end power of the CYC is very noticeable compared to the Levo.



Gearing Analogy:



Thinking about the CYC gearing choices, I think a car makes a good analogy. The maximum RPM you can pedal the bike at would be like the redline of the car’s engine. Then there is the gear ratio between the motor (first number) and chainring (second number) which is like the gear the car is in.



For the 11/53, one turn of the motor would generate 0.208 turns of the chainring. For 11/63, one turn of the motor would generate 0.175 turns of the chainring. So the 11/53 gear will drive the cranks/pedals further and faster than the 11/63 per each turn of the motor. I believe that is what contributes to the feeling of better low end torque on the 11/53. It drives the chainring faster for a given RPM which ultimately determines your speed.



The downside of this is that you will not be able to reach as high of a motor RPM before your legs hit redline. When I pedal the 11/53 as fast as my legs can possibly go, I can hear and feel the extra RPM the motor is willing to give me, but I am rarely able to use. The other gearing choices will allow you to reach those motor RPMs more easily and utilize that extra power.



If you’re considering a hybrid gear setup, use the printouts to make sure you have the clearance. I made the 11/53 work with a 38 tooth, but am not sure if the 42 tooth would have been compatible. And the 42 tooth wouldn’t fit on my bike or many others.



For reference, here is CYC’s explanation on the gearing selection.



https://www.cycmotor.com/chainring-options-explained



I’m open to other users feedback on their gearing choices, especially if they are using their bike as a trail / mountain bike. Hopefully this was useful to you if you are currently looking at gearing choices for your bike. I know the forums were and still are a valuable resource for me.