Because I ride off road only, I modified my BBS02 by using a 28t chainring which reduced top speed to 20 mph. Is it feasible to limit your speed with an appropriate chainring/cassette combination? You would have amazing torque.
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CYC Photon Gen 2?
- Thread starter raylo32
- Start date
Many countries have legislation that require this, though enforcement is a different matter. It only takes group of idiots to trigger a news story and then a witch hunt for those evil ebike criminals. There is also a real danger - people die in fires started by batteries.
The real problem for us DIYers is when enforcement of battery standards (eg UL2271) (and then installation and wiring systems - eg UL2849) is legislated.
Gouache might have a compliant battery system but it is huge and expensive, and doesn't address the other issues like UL2849. I don't know of any others. Maybe an eventual change to other battery chemistries will help, but probably not in my lifetime.
I don't see any evidence of CYC addressing this, I reckon they've got to do something in the next 5 years or so, or they will just be selling into an (even more) niche market.
Melobear
🧲 New user
I've come into a small issue, maybe someone has an ideea,
I can hear cable noises when pedaling, but nothing is touching anything, triple checked.
I think its the zip ties - cable - combination that I hear, def some plasticky sound
perhaps loosening the zip ties could help? maybe they are a little too tight. or could be something else?
Bike and motor works perfectly and doesnt touch, I ve tested with it upside down, pedaling and throttle, so this is my only guess if I take the sound into account (plasticky, stretchy somehow)
I can hear cable noises when pedaling, but nothing is touching anything, triple checked.
I think its the zip ties - cable - combination that I hear, def some plasticky sound
perhaps loosening the zip ties could help? maybe they are a little too tight. or could be something else?
Bike and motor works perfectly and doesnt touch, I ve tested with it upside down, pedaling and throttle, so this is my only guess if I take the sound into account (plasticky, stretchy somehow)
Some of us want to follow the law, and want a bicycle that helps?
lisalis
🔌 New-ish
cyc answered btw
"Yes, you can make your setup compliant with Swiss regulations. The throttle can simply be left unplugged or removed physically, and the system will run pedal-assist only. For speed limiting, you can set a 45 km/h limit in the app. This setting is stored in the controller, so the bike will respect it even if the display is connected. The Intuition Display only shows ride data—it cannot change speed limits or advanced settings.Currently, there’s no additional lock mode."
"Yes, you can make your setup compliant with Swiss regulations. The throttle can simply be left unplugged or removed physically, and the system will run pedal-assist only. For speed limiting, you can set a 45 km/h limit in the app. This setting is stored in the controller, so the bike will respect it even if the display is connected. The Intuition Display only shows ride data—it cannot change speed limits or advanced settings.Currently, there’s no additional lock mode."
After a lot of riding, I’ve realized I stick to 2 kW mode because my gearing naturally aligns with the motor’s power curve: low gears give low power, tall gears hit near 2 kW, and intermediate gears cover everything in between. This lets me control power and speed mechanically, without changing modes. Power ceilings mostly act as limits, only useful for very steep climbs, thermal management, or gentle throttle power limit when needing tall gears (like when using PAS). With PAS, I tune assistance mathematically for smooth pedaling, so staying uncapped preserves natural feel rather than a power chop. Essentially, gears and tuning do the work for power/speed limits, and software power limits are only needed in edge cases, so I mostly use 2kw “uncapped” mode as a one size fits all.
The gearing I’m using is 12 speed 11-51T and 38T. The 3 lowest gears are only like 100-300w which is very slow on a flat so you could do 5 speed gearing for flats just fine. This also tells me with my setup a bigger chainring wouldn’t make the bike any faster on throttle, because it matches the power curve, the tallest gear is already the base speed gear and any higher one would just be slower acceleration. A much bigger chainring however like 50T may allow you to contribute pedaling for a higher top speed but at the cost of sacrificing lower gearing and acceleration, but having a wide range cassette like a 12 speed gets around that.
Interesting is that in lower gears where it’s drawing lower watts, it’s much louder. At lower base speed gears, it’s drawing so little watts, it’s trying very hard to not overshoot torque while applying basically zero, so it’s pulsing rapidly. Rapid transitions between zero-current and non-zero current, irregular PWM groupings, strong excitation of stator and gear resonances is what you hear. It’s not straining, but control granularity. I’m not as knowledgeable on this but it seems other motors like Brose tend to be much quieter in the same situation because of a very low internal ratio, lower cogging of torque, belt primary reduction, and better field oriented control (high pwm frequency, smoother behavior, better current sensing). It’s a bit unrealistic to have the same design for a high power motor that is designed to be more robust and aggressive, and anything you could add would drive the cost up a lot with little benefit
The gearing I’m using is 12 speed 11-51T and 38T. The 3 lowest gears are only like 100-300w which is very slow on a flat so you could do 5 speed gearing for flats just fine. This also tells me with my setup a bigger chainring wouldn’t make the bike any faster on throttle, because it matches the power curve, the tallest gear is already the base speed gear and any higher one would just be slower acceleration. A much bigger chainring however like 50T may allow you to contribute pedaling for a higher top speed but at the cost of sacrificing lower gearing and acceleration, but having a wide range cassette like a 12 speed gets around that.
Interesting is that in lower gears where it’s drawing lower watts, it’s much louder. At lower base speed gears, it’s drawing so little watts, it’s trying very hard to not overshoot torque while applying basically zero, so it’s pulsing rapidly. Rapid transitions between zero-current and non-zero current, irregular PWM groupings, strong excitation of stator and gear resonances is what you hear. It’s not straining, but control granularity. I’m not as knowledgeable on this but it seems other motors like Brose tend to be much quieter in the same situation because of a very low internal ratio, lower cogging of torque, belt primary reduction, and better field oriented control (high pwm frequency, smoother behavior, better current sensing). It’s a bit unrealistic to have the same design for a high power motor that is designed to be more robust and aggressive, and anything you could add would drive the cost up a lot with little benefit
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So, the motor doesn't break 10-speed chains before you ever even ride them? Twice?
Why am I gonna try it again like a retard? Possibly it was a bad batch?
I hear CYC makes some noise.
I’m not sure what you mean by that, but as far as chains breaking, my 12 speed kmc ebike chain has held up just fine, lower speed chains should be better
lisalis
🔌 New-ish
I'm fishing for lights for my cyc photon build. I've found something https://de.aliexpress.com/item/4000833729468.html which seems quiet good for a 52v system but it uses a 2 pin Higo male connector. I need a xt-90 male for the photon right?
Does it connect to the harness of the photon or am i missing something? is there even enough space on the harness or should i get an extension like to double xt-90 connections ??
Does it connect to the harness of the photon or am i missing something? is there even enough space on the harness or should i get an extension like to double xt-90 connections ??
Idk, 2 some kinda chains broke with a BBS03 while it was upside down, before any fatass-type stress was put on them, was my train of thought. Possibly bad derailleur, possibly weak chains. Pretty sure they were 8-speed, not 100%, though
One broke in the middle of the link, Ay! I took measures to correct that problem. I forget what, and that's not good.
You would need to splice an xt-90 on it, or get the one from electrifybike co that already has the xt-90 when it’s back in stock
What about the CYC lights? They are about the same price.
Output gear bearing (gen 2)
Those with the new Photon, how do you rate the weather/water tightness of the large bearing behind the chainring? On the original Photon, the design seems to rely on the bearing's own rubber shield for protection, and this doesn't seem to be enough. This is located in a very dirty area that is impossible to inspect or clean. On the original there is an unprotected ingress route between the chainring carrier and the ring that retains the bearing into the motor casing, did CYC address this?
Those with the new Photon, how do you rate the weather/water tightness of the large bearing behind the chainring? On the original Photon, the design seems to rely on the bearing's own rubber shield for protection, and this doesn't seem to be enough. This is located in a very dirty area that is impossible to inspect or clean. On the original there is an unprotected ingress route between the chainring carrier and the ring that retains the bearing into the motor casing, did CYC address this?
Idk but I’ve ridden in a lot of rain so far and it seems fine after I took it apart to regrease, but I didn’t inspect the internals too deeply. The chainring design is also different from the gen 1 as everything is built in except the teeth and guard
lisalis
🔌 New-ish
Sadly they look subpar. I dont want 2 lights on my bike for low/high beam
Also I heard these lights suck. Can only be bought in pairs and one light may go out after less than a year
Btw guys you should tape or shrink wrap the main connector if you don’t plan to take it off often, it’s reportedly pretty fragile with people snapping the plastic ring and I personally accidentally bend the pins 30% of the time and have to bend them back. I say secure it shut because most of the time it disconnected it was accidental
oregonxc
🧲 New user
I have just over 1000 miles on mine. Ride off road in muddy rainy western Oregon coast range. Just regreased it. No water intrusion that I can tell. I am waiting on a warranty controller because the display doesn’t connect and the throttle comes on full speed with no throttle connected. Works fine with no display, wiring harness jumped and throttle disabled in the app.
I believe if you jump it, the throttle will be full power no matter what and you can’t turn it off. Have you considered the display is damaged? Two of mine damaged very easily on minor bumps where you can’t even tell it broke from the exterior. I’ve opened one up and couldn’t tell much but my theory is the ribbon cable it has is very fragile and easily unseats, or the lcd is somehow making contact with the pcb. Also how did you manage to jump it? I considered trying it but since it’s a new layout and canbus now, I wasn’t confident trying that strat they used with the gen 1. Didn’t find anything on the gen 2 for that at the time
raylo32
🚴♂️ Mega poster
The sw102. Haven’t tried the round one but it looks like a more safe position
I learned the hard way why the zip ties and double sided tape that came with the a52L was not enough to hold it on the downtube after I cased a terribly steep jump. Many of you probably knew a hose clamp would be better, however that was incompatible with my frame. But this failure also proved why I chose this battery, not a dent or scratch on it
I have one of CYC's older zip up batteries, couldn't use the supplied mount - nor did I want to. I use a pair of 600mm x 50mm hook and loop straps, dead simple, easy to remove for charging (I don't keep large batteries in the house) and really holds the battery in place without stressing the frame. had a huge crash last week (wort ever) and battery didn't move at all.
That’s awesome man. I ended up using ratchet straps and put heat shrink on them, then doubled up the tape thickness
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