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CYC PHOTON

150? Thems some short cranks.
That's about 17 percent shorter than "long" 175mm cranks. People's leg length varies a lot more than that.

I have cranks on my bikes from 127mm (for my adult sized Big Wheel) to 225mm (for my high bottom bracket MTB). Most of my regular bikes have 185mm or 190mm cranks, but others are as short as 165mm. The shorties spin faster with less effort, the long ones push bigger gears with less effort.

Why the industry has decided that every adult of every size should have 170mm to 175mm cranks (3% difference) is pretty mystifying to me. But one thing I've learned by trying different length cranks is that too short is easier to work with than too long.
 
Agree, I had really tighten mine just to stop the sloppy 34t chainring from rattling around.

The "Retaining Lock Ring" on the left side is equally problematic. CYC say to "hand tighten". Whatever that is.

If you don't tighten enough by hand, the bearing has enough resistance (actually, it has a lot of resistance, seemingly caused by the plastic sleeve) that the shaft will spin inside the plastic sleeve. If this happens the bearing interface becomes the inside surface of the plastic sleeve against the shaft; the actual bearing is not spinning at all. Far from ideal.

If you over tighten the ring by hand, you will destroy the two end bearings by over-preloading them. Not great either.

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Do other motors like toseven dm01/dm02/tsdz2 have similar issues?
Any workaround? Sugestions?
 
Dropper posts arent required for the majority of the riders.
Disagree. Most people don't even know they exist.

Consider the use case for older and less confident ebikers - they always ride with the seat low so they can touch the ground when they stop around town, but for longer rides where this isn't a factor, a dropper could set the seat to the correct height. would definitely help their knees if they are putting in any effort at all.

There is also a use case for shared and family bikes - easy adjustment on the fly.

It isn't just about flying down a hillside.
in poland you will find it hard to find new mtb WITHOUT one ...
 
Does really 1-2cm make a difference for you?
If you use 20mm shorter cranks, you need to raise your seat height by about the same. The top of your stroke will be 40mm lower relative to your previous position, that is quite a significant difference, and might be game changing for some people.
 
I have a problem with my 2nd Photon MTB build:
After less than 100km the motor freewheel seems to be non-functional. So now, if you pedal with motor disabled, you can hear and feel (resistance) that the motor is turned.
Does anyone know this?
Where is the motor freewheel located?
Can it be "freed" again, maybe some particle git in the wrong place?
 
I have a problem with my 2nd Photon MTB build:
After less than 100km the motor freewheel seems to be non-functional. So now, if you pedal with motor disabled, you can hear and feel (resistance) that the motor is turned.
Does anyone know this?
Where is the motor freewheel located?
Can it be "freed" again, maybe some particle git in the wrong place?
I think there are 2 spragg clutches, a large one between the axle and the chainring (you can see this behind the chainring locking ring). I think the other spragg clutch is inside the motor housing, possibly on the larger output gear, I don't think it is easily accessible.

On my bike I can feel the motor turning when I rotate the chainwheel backwards, but is free when rotating forwards. The motor drag would be significant.

There is passing reference in Rikus' video:


and also I think there is an exploded view somewhere on the CYC website. Somebody may even have posted some photos elsewhere on this thread.

I think it is unusual for spragg bearings to fail like that. What have CYC said?
 
Thanks for the info regarding the spragg clutches. I disassembled cranks and chain wheel and checked the large sparagg clutch behind the chain wheel locking disk: This one is ok, it is the one that disconnects upon pedaling backwards. So the one not disconnecting correctly is that internal to the motor housing.
I further observed: The suspicious one does not fully connect the motor while pedalling (with motor support disabled), it seems to drag the motor only a bit. That means, even if you pedal very fast, the motor only is turned rather slow. If you do sudden pedal strokes from still pedals, the internia of the motor mass even lead to not turning the motor at all.
So in other words: This internal spragg clutch only has a slight unintended behavior, it seems to have a small amount of drag, enough to spin the motor a bit.
However, I think I will report the issue to my dealer (faster bikes.eu) and see what they say...
 
This internal spragg clutch only has a slight unintended behavior, it seems to have a small amount of drag, enough to spin the motor a bit.
It may not be the clutch - it could also be a stiff bearing or unwanted friction elsewhere in the drive train, and which might be there all the time, you just don't notice. Frustrating.

May be worth emailing CYC directly as well as your dealer.
 
What's the weight of this with mounting parts? (Not just motor) my googlefu failed edit, does this sound accurate at all, 3.9 kg ?
 

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Also is it explicitly stamped at 750w anywhere on the motor, for legal reasons? Kinda paranoid about the 1000w stamp on BBSHD
i wish they just put a 250w stamp on. anyways, ive put a 250w sticker over the stamping. will it work when im stopped? guess i have to find out
 
Have you ever seen Police stoping ebikers?
Luckly in Poland Police Has better things to do.
Maybe in Germany or UK Police is more obsessed with ebikes and checks whether you can ride over 25km/h with motor active.
 
Have you ever seen Police stoping ebikers?
Luckly in Poland Police Has better things to do.
Maybe in Germany or UK Police is more obsessed with ebikes and checks whether you can ride over 25km/h with motor active.
I think it's pretty common anywhere the sur ron was popular like South Bay los Angeles, orange county, San Diego, or areas like San Francisco. In California at least.
 
More often than not the forums are the place where people come to complain.
But today I want to testify to the exemplary functioning of my Photon motor. Everything is going wonderfully. The noise is practically non-existent and the torque sensor response is precise. It's a real pleasure to go on the road with this motor. I don't believe that a bike using the Bosch system can be superior.
We quickly forget the price paid.
I've included a typical screenshot taken today with an outside temperature of 13C. Note that assist level 3 means 3 on 9.
IT looks like they fixed human power calculation?
75w looks ok with 180w motor power.
 
3.9 kilos sounds pretty close! I weighed mine and seem to remember a little over 8 pounds.
hmm ok. Anyone know the mounted weight mounted minus the display and other peripherals, that would also help to compare, the BBSHD controller parts etc add about 3 lb, 13+3, or 9.5+3 for bbs02.
what is the photon supposed to peak at with 750 continuous version? or the 250w, (does that weigh any less). Here's a vid of it doing 2000w/1500w unrestricted https://www.you tube.com/watch?v=H22lb000m0U
 
hmm ok. Anyone know the mounted weight mounted minus the display and other peripherals, that would also help to compare, the BBSHD controller parts etc add about 3 lb, 13+3, or 9.5+3 for bbs02.
what is the photon supposed to peak at with 750 continuous version? or the 250w, (does that weigh any less). Here's a vid of it doing 2000w/1500w unrestricted https://www.you tube.com/watch?v=H22lb000m0U
My guess would be that the weight changes depending on the chainring tooth count and spindle width choices, not wattage, which is just a setting.
 
My guess would be that the weight changes depending on the chainring tooth count and spindle width choices, not wattage, which is just a setting.
Yes the weight will change slightly depending on the chainring and spindle. It is a solid 2# or 1 kilo lighter than a bbs02. It is less than 9# with the small display, wiring harness, ,mounting bracket etc.
 
what is the photon supposed to peak at with 750 continuous version? or the 250w, (does that weigh any less)

There is only one Photon version. There may be another motor released later (Proton) but I hope CYC don't release that for some time. They've got a lot to sort out with the Photon and business operations and systems at this stage.
 
There is only one Photon version. There may be another motor released later (Proton) but I hope CYC don't release that for some time. They've got a lot to sort out with the Photon and business operations and systems at this stage.
The Facebook group is pure salt.

Is the Photon clearly engraved as 750w by the factory, like the bbs02 or the Luna BBSHD? Does cyc have any other motors engraved as 750
 
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There's a Photon up for sale on eBay (U.S., east coast), and the owner describes issue(s):
  • The kit functions as it should with the exception of both brake sensors not working as they should
  • When 'brake sensor' is enabled in the CYC app, and BOTH brake sensors are plugged in, the throttle doesn't work and both brake sensors don't register magnet movement ( turn blue)
  • When there is just one brake sensor plugged in, the system registers magnet movement to that specific brake sensor- however the throttle still does not work
  • I've pretty much been riding this without the sensors connected - on pedal assist and throttle. Both work when the brake sensors are NOT plugged in
  • I've been in touch with CYC about this issue and they offered to send a replacement harness and two new brake sensors even though I don't think that's the problem. I personally think it's related to software or firmware but I could be wrong. The first thing I did when I got the kit was update the controller firmware through the app which was successful.
My bet is the main harness - but it could be in either segment. I find it curious that the seller didn't take CYC up on their offer, and decided to bail after stating it has all of 6 miles riding time. I also feel that the asking price could scare off most risk-takers. But what do I know?

Plugging everything in, then running the App throttle calibrator might give more clues - are the end voltages way off, for example.

I bought directly from CYC, a 1-plug main harness (display only) - no worky. Not much to go on, but it could be that CYC has some questionable harnesses out there.
I ended up taking a chance on this Photon with the intention of using it for pedal assist only. I paid under $600 including tax and shipping. I installed it on a (non-e) commuter bike I've had for years and so far so good. I've only put a couple hundred miles on it so far, bit it's working great. I haven't bothered to look in to the problem with the brake sensors given it's suiting my needs as is.
Could someone explain to me what the advantage of having brake sensors is? This is only my second ebike (my other being a Triobike Cargo with an older Bionx hub-drive) so I don't have a lot of experience with different mid-drives.

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Is the Photon clearly engraved as 750w by the factory,
Not on mine. The only flat areas are the two ends, which have CYC printed on them. Almost everything else is finned heatsink.

I don't think there is any point labelling the motor power since the legal limit varies by jurisdiction. For example in NZ it is 300W and no speed limit (other than road or path speed limits of course). 250W or 750W labels would be irrelevant.
 
I ended up taking a chance on this Photon with the intention of using it for pedal assist only. I paid under $600 including tax and shipping. I installed it on a (non-e) commuter bike I've had for years and so far so good. I've only put a couple hundred miles on it so far, bit it's working great. I haven't bothered to look in to the problem with the brake sensors given it's suiting my needs as is.
Could someone explain to me what the advantage of having brake sensors is? This is only my second ebike (my other being a Triobike Cargo with an older Bionx hub-drive) so I don't have a lot of experience with different mid-drives.

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Hey, that's great - glad it's working out and in use.

I think, while not absolutely needed, the brake cutoffs are good to have for safety, especially for returning riders. I have cutoffs on my loaner bike. There have been some pretty serious injuries from unexpected launches.
 
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