SZZS specific CEF50-main thread (initial builds and troubleshooting related only)

Waynemarlow

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Dec 6, 2019
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Unless you bought your frame, motor and battery used. You are not going to get those prices from Dengfu and then that does not include any other parts. Unless you had all the parts anyway and then it is not accurate for anyone else.
Correct, as of 2023, but do understand that I purchased my E10 before it had media presence shall we say, Dengfu offered a deal which I couldn’t refuse being a very very early adopter. In mitigation to myself, you can get remarkable deals on slightly used components. My Z1 forks were £170.00 delivered to my door, hardly a mark on them, my full Hope brake set I already had along with all the other components such as a 10spd Shimano group set ( you will thank me in the long term if you use only 10spd set ups ) on a top of the line analogue bike. I sold the frame which paid for the Z1’s. I built my own battery using the best quality cells saving large amounts of cash and weight. But then only a few can take on this type of build. Yes you can build cheaply with top components. Incidentally my E10 is 23.5kgs.

Have I got a lessor bike than buying completely new components, only to those with large bank accounts. But that was not what I was bitching about. Can I repeat, creating your own DIY bike may match a branded bike components wise at a much reduced cost, but bear in mind that probably 50% of the cost of a bike bought at your local LBS, is manufacturer back up when things go wrong.

Would I go down this DIY route again, I’m not sure as much as I enjoyed the build and as much as my bike cost me less than £ 1500. I can buy a very low mileage EZesty for 60% of the new component cost. It’s a full 50Nm 150/160 travel bike weighing in at 20kgs. You can even take the motor and battery out and use it with your analogue mates. But is it brand new, nope, have you had the fun of designing and building your own bike, nope. My advice as much as I seem to be reticent about the process, is to ask the question of what you really want from owning a bike, is it just the riding of or more a complete process of picking components and build as much as riding ?
 

TCFlowClyde

Active member
Feb 26, 2022
1,335
863
Mesa, AZ
A lot of reference here.
I decided on 36v 720wh and it is said to be shipped next week.
I Believe and wait...:):)
Bravely done! Welcome to the unicorn build!🦄 It should be interesting to compare experiences.🤛

Now let's hope that the future RobRides
review can put the M820-75 through the paces, especially on peak wattage of the power modes! 💪
 

mike_kelly

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Aug 11, 2022
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Correct, as of 2023, but do understand that I purchased my E10 before it had media presence shall we say, Dengfu offered a deal which I couldn’t refuse being a ...
You bring up good points. But you also show that most people probably can't do what you did. Getting good deals is a lot a matter of timing and good luck in shopping. Also being your own "product manger" is not without pitfalls. Making sure everything works with everything else is a challenge and if you make mistakes, which is easy to do these days with all the proprietary products, then you lose money.

I think most of us that do DIY are pretty self sufficient. I don't need bike shops at all. Also with the eMTB the motor and battery are big expenses and it would be very expensive to ship one back for warranty repair replacement.

I love building bikes, I have 30 in my stable, but it is not a short cut to cost savings for the average person.
 

TCFlowClyde

Active member
Feb 26, 2022
1,335
863
Mesa, AZ
CEF50 720Wh (45.6 lbs) v. Relay 430Wh (PNW) (44.6 lbs est.).🫣

✔️Rob weighs a large, non-PNW build as 42.92lbs. (see below)

✔️Rob estimates the PNW build to be 700 g/ 1.54 lbs) more for a speculative total of 44.6lbs. (actually very impressive!)

My build v. PNW build.
-180mm (38) front v. 170 = (+10mm)
-165mm rear v. 170 = (-5mm)
-220mm rotor v. 203mm = (+17mm)
- 720Wh v. 430Wh = (+290Wh)
- 820-75 Nm v. Fazua60 = (+15 Nm)
- Difficult motor drop battery v. Easy popout = (neutral for range), (- for travel), (- charging ease)
- Ride w/battery v. Ride w/o battery = (-)
- Less stealthy v. More stealthy = (-)
- Less quality control v. High = (-)
-$5.5k v. 11 k = (+/+/+/+/+)
- 3 yr warranty v. lifetime =( -/-/-/-)
- support low v. support high = (-)
- DIY serviceable v. none = (+)
- M820 motor reliability v. Fazua60 = (neutral)
- 820-75 4.9lbs/2.34kg v. Fazua60 4.3lbs/1.96kg = (-.6 lbs)
- 45.6lbs v. 44.6lbs = (-1 lbs)
-------------------------
Sum 10+ v. 12- = (2-)

Key differences (qualitative):
1. The bigger battery compensates for the ability not to swap out the smaller battery with ease, so greater range (290Wh).
2. More powerful motor 75/95Nm peak.
3. Half the cost for 1 more lb.
4. DIY serviceable

Conclusion: So, the numbers are there for me at least, and certainly the subjective categories are mine, but reasonably can be generalized.🤙
Screenshot_20230314-072714.png
 
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Stephen B

Member
Feb 24, 2021
107
53
El Dorado Hills, California USA
This looks VERY progressive to me. Starting at a leverage ratio of 3.6 at beginning of stroke and ending with a leverage ratio of 2.5 at end of stroke. Compared to the E10: 3.1 to 2.6 according to chart attached.
My takeaway:
- Coil shock would be a better choice due to linear spring rate
- Overstroking 216/63 would raise the rear by (6mm longer shock x 2,5 ratio) 15 mm and increase travel by (13 mm increased stroke x 2,5 ratio) 32,5 mm! to 180+ mm rear travel!
- Overstroking 210/55 would increase rear travel (5 mm increased stroke x 2,5 ratio) by 12,5 mm to appr. 162,5 mm

Sound promising!
If this is true does that mean that a coil shock would be a better choice than a air shock?
 

Suns_PSD

Active member
Jul 12, 2022
515
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Austin
I did try and get a frame weight out of Transition and they stated " since we don't have production models of those physically here yet, we have not weighed them yet..."

I asked them about the possible 2# weight gain & loss of frame strength from the removable battery and they stated: "we have to use more material in the layup for strength and stiffness compared to a closed cross section tube. In our case it's definitely not a 2lb weight penalty..."

Saving money is great, but first and foremost I want the best frame & motor I can get. I do believe the F60 is the best mid power motor if being stealth is important to you, and it certainly is to me. Transition geo is always spot on. Then I just try and find the best frame only price.

But this is a BIG price difference!

I'm still watching the Relay (have a deposit and even ordered a CF DH rear 27.5" wheel), but also carefully watching for the new Spesh Levo SL and of course the CEF50, which is a heck of a product.
 

Suns_PSD

Active member
Jul 12, 2022
515
421
Austin
If this is true does that mean that a coil shock would be a better choice than a air shock?

First, the proper way to measure LR is from the sag point at 30%, to 95% travel where bumpers and air ramp make the LR irrelevant anyways.

I went back and found the chart and got these numbers: LR at 30% is 3.23, LR at 95% is 2.57. so .66/ 2.57 = 26% progression. Which in my experience is the BARE minimum for a large volume air shock.

So is a non-reservoir air shock appropirate on this frame? No. Not only because of the travel, intended usage, and weight of the bike but also the progression ratio. Those shocks work well on XC bikes in part because they tend to be very linear.

Is a coil shock appropriate for this frame? No. First, I hate coil shocks but if you want to ride a coil aggressively you need a lot more travel to have more time to absorb the energy or much higher progression, as in over 35%. Also a HL e-bike with a LR this high is going to require a very heavy shock spring adding not only a lot of weight, but very possibly not even existing for riders over 190#s.

This bike's LR puts in firmly in the camp of needing a reservoir style air shock. If you don't jump or do any g-outs run few to no volume reducers. If you are aggressive, stuff it full.

Make sense?
 

TCFlowClyde

Active member
Feb 26, 2022
1,335
863
Mesa, AZ
I did try and get a frame weight out of Transition and they stated " since we don't have production models of those physically here yet, we have not weighed them yet..."

I asked them about the possible 2# weight gain & loss of frame strength from the removable battery and they stated: "we have to use more material in the layup for strength and stiffness compared to a closed cross section tube. In our case it's definitely not a 2lb weight penalty..."

Saving money is great, but first and foremost I want the best frame & motor I can get. I do believe the F60 is the best mid power motor if being stealth is important to you, and it certainly is to me. Transition geo is always spot on. Then I just try and find the best frame only price.

But this is a BIG price difference!

I'm still watching the Relay (have a deposit and even ordered a CF DH rear 27.5" wheel), but also carefully watching for the new Spesh Levo SL and of course the CEF50, which is a heck of a product.
Yeah, same for Transition frame weight for large in my case...they were wiley.

I think they did a great job quality-wise. Can't beat lifetime warranty/support!

Really setting a gold standard for this Enduro/"trailduro" mid-powered weight class. I agree that easy swappable battery is key. I would just backpack a full spare for me. I could live with that EXCEPT for motor power, reliability and serviceability.

It's the Fazua60! I found it better than the TQ50, but less impressive than the RS60 for turbo/boost. Ridden them all in the past 6 months. But, depends on expectations from baseline. If you ride full-powered the RS60 does it but barely. If you ride analogue, they all are awesome!

The M820-75 is the unicorn motor.🦄 75-95 Nm peak is freakishly curious. RobRides should flesh out the fat!
 

TCFlowClyde

Active member
Feb 26, 2022
1,335
863
Mesa, AZ
Yeah, same for Transition frame weight for large in my case...they were wiley.

I think they did a great job quality-wise. Can't beat lifetime warranty/support!

Really setting a gold standard for this Enduro/"trailduro" mid-powered weight class. I agree that easy swappable battery is key. I would just backpack a full spare for me. I could live with that EXCEPT for motor power, reliability and serviceability.

It's the Fazua60! I found it better than the TQ50, but less impressive than the RS60 for turbo/boost. Ridden them all in the past 6 months. But, depends on expectations from baseline. If you ride full-powered the RS60 does it but barely. If you ride analogue, they all are awesome!

The M820-75 is the unicorn motor.🦄 75-95 Nm peak is freakishly curious. RobRides should flesh out the fat!
PS. Just me, if I had 11k+💸....for two lbs more, I would go Orbea Wild LTD EP8-85/625Wh battery. Guaranteed true, full-powered and a bigger battery to support needed capacity.

But I don't have $$$....my budget is tapped out for the year on the CEF50 /720Wh! And I don't have a sugar mama (yet😉) and I refuse to sell my kidney (also yet!😜).
 

mike_kelly

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Aug 11, 2022
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Thank you
The 43v is better because the power cables from the battery can be smaller. Power is the same. If you have two batteries of the same watt-hours and one is 43v and one 36v then it is the same energy stored. The more voltage the smaller the copper cables, which is lighter(a bit). But in reality they probably use the same larger cables for both units for economy of scale in manufacturing.
So it may not make any difference. I think it might be easier to find a third party external battery for 36v than 43v. Just from my shopping around.

But a 410whr battery is gong to take you on a little longer ride than the 360whr battery. It does not matter what the voltage is. Watt hours is watt hours. It will also be a little heavier. Trade-offs.

I have never understood the love with coil shocks. They are heavier than air shocks. The coils are also only made in certain weight increments so it is likely you are going to have to compromise on the weight being not close to what you actually weigh and you have to do some real guessing what coil to get given the details of your rear suspension system.
With an air shock you can pump them up to exact the right amount for you.
 
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TCFlowClyde

Active member
Feb 26, 2022
1,335
863
Mesa, AZ
The 43v is better because the power cables from the battery can be smaller. Power is the same. If you have two batteries of the same watt-hours and one is 43v and one 36v then it is the same energy stored. The more voltage the smaller the copper cables, which is lighter(a bit). But in reality they probably use the same larger cables for both units for economy of scale in manufacturing.
So it may not make any difference. I think it might be easier to find a third party external battery for 36v than 43v. Just from my shopping around.

But a 410whr battery is gong to take you on a little longer ride than the 360whr battery. It does not matter what the voltage is. Watt hours is watt hours. It will also be a little heavier. Trade-offs.

I have never understood the love with coil shocks. They are heavier than air shocks. The coils are also only made in certain weight increments so it is likely you are going to have to compromise on the weight being not close to what you actually weight and you have to do some real guessing what coil to get given the details of your rear suspension system.
With an air shock you can pump them up to exact the right amount for you.
On the coil I was super interested until I started hitting the higher spring rates...the coil weight was increasing too much. And an adjustable Springdex was possible with a lighter steel spring but I was still pushing the limits. Hence my Ultimate Meg-neg air...saving some critical lbs on my burly Enduro build.
 

TCFlowClyde

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Feb 26, 2022
1,335
863
Mesa, AZ
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Myalteregohamish

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Jan 4, 2023
294
240
Vancouver, WA
I've read all the messages on this build and it's been an incredible amount of helpful thoughts, considerations and opinions. So let me just say thank you for starting all of this. So, Ok I did it, made the purchase this morning. XL, had them paint it based on a sample image I gave them. Going with a 720wh battery. I asked them about smaller cranks than the 170's it comes with. Linda told me that Bafang are working on 160's but not yet. That's ok I'll just get some after it arrives. Very curious about the feel of the power delivery. I don't need a huge punch but I want to know it's supporting me.

I have a KSL right now and I love it. It's the best uphill/downhill I've ever owned. It's my first e-bike so I've never owned anything that can produce high torque (80-90nm) and power (+500w). That said, I am fit 6'2" 180lbs, I can put out 350-450 watts for a couple of mins on a punchy climb. However the KSL match is limited to 290 watts of output. I can usisally get about 2hrs of riding out of it. But I did buy the extender.

So with all of that in mind, with upgrades to brakes and tires, the bike sits in at 43.5lbs. I'm not complaining but if I want to use something more than eco mode then I really need the range extender bringing the weight up to 46.5 lbs. To quote my buddy with FF Kenevo, "I just need to figure out where to drop 4lbs to get to KSL weight?".

So when you think about range and what you need vs not need. I ride a variety (I think most people do as well) of trails some tight and technical. Some are downhill chunky monkeys and everything in between. So at some point you are going to want to do something that ~400wh's isn't going to be enough for and for that I'd say get the 720wh and forget about it. With 75nm at disposal I'm thinking you're going to have all the support you will need to get up and down.

People talk about playful bikes and I think given a single bike, I will make it behave playful enough for me. Which may mean more upper body workouts. I want my rides to be fun, turning the power up allows me to turn cross country into intermediate downhill. I love that an eMTB can do that. I don't really want to have to calculate how far with how much can I go today.

That said I am taking my 2022 stump jumper EVO and stripping it for GX drive train, code R brakes, 223 rotors, Nuke proof horizon V2's (and a new 27.5 for the mullet), Fox 36 160mm (probably though in a new 170MM airshaft) in front and Float X in back (165mm travel mod with 210x55). I've purchased the hardware from lost co for the shock fit.

I love to work on, build bikes and the most frustrating thing about a Specialized eBike is that I have to go to a dealer for any "e" related work (software, hardware etc). This project has afforded me a bit more idependence at a price point that is less than 2k USD.

That said I"m looking forward to seeing some wattage output numbers that riders are seeing on their new M820s.
Thanks for all the help
Andrew
 

TCFlowClyde

Active member
Feb 26, 2022
1,335
863
Mesa, AZ
I've read all the messages on this build and it's been an incredible amount of helpful thoughts, considerations and opinions. So let me just say thank you for starting all of this. So, Ok I did it, made the purchase this morning. XL, had them paint it based on a sample image I gave them. Going with a 720wh battery. I asked them about smaller cranks than the 170's it comes with. Linda told me that Bafang are working on 160's but not yet. That's ok I'll just get some after it arrives. Very curious about the feel of the power delivery. I don't need a huge punch but I want to know it's supporting me.

I have a KSL right now and I love it. It's the best uphill/downhill I've ever owned. It's my first e-bike so I've never owned anything that can produce high torque (80-90nm) and power (+500w). That said, I am fit 6'2" 180lbs, I can put out 350-450 watts for a couple of mins on a punchy climb. However the KSL match is limited to 290 watts of output. I can usisally get about 2hrs of riding out of it. But I did buy the extender.

So with all of that in mind, with upgrades to brakes and tires, the bike sits in at 43.5lbs. I'm not complaining but if I want to use something more than eco mode then I really need the range extender bringing the weight up to 46.5 lbs. To quote my buddy with FF Kenevo, "I just need to figure out where to drop 4lbs to get to KSL weight?".

So when you think about range and what you need vs not need. I ride a variety (I think most people do as well) of trails some tight and technical. Some are downhill chunky monkeys and everything in between. So at some point you are going to want to do something that ~400wh's isn't going to be enough for and for that I'd say get the 720wh and forget about it. With 75nm at disposal I'm thinking you're going to have all the support you will need to get up and down.

People talk about playful bikes and I think given a single bike, I will make it behave playful enough for me. Which may mean more upper body workouts. I want my rides to be fun, turning the power up allows me to turn cross country into intermediate downhill. I love that an eMTB can do that. I don't really want to have to calculate how far with how much can I go today.

That said I am taking my 2022 stump jumper EVO and stripping it for GX drive train, code R brakes, 223 rotors, Nuke proof horizon V2's (and a new 27.5 for the mullet), Fox 36 160mm (probably though in a new 170MM airshaft) in front and Float X in back (165mm travel mod with 210x55). I've purchased the hardware from lost co for the shock fit.

I love to work on, build bikes and the most frustrating thing about a Specialized eBike is that I have to go to a dealer for any "e" related work (software, hardware etc). This project has afforded me a bit more idependence at a price point that is less than 2k USD.

That said I"m looking forward to seeing some wattage output numbers that riders are seeing on their new M820s.
Thanks for all the help
Andrew
I'm sure it will meet your power and range needs as you described.

Welcome to the 720Wh-unicorn faction of the CEF50 thread🍻
 
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Myalteregohamish

Active member
Jan 4, 2023
294
240
Vancouver, WA
This whole project reminds me of when I used to build hackintosh computers, getting Mac OS to run on generic PC hardware to avoid the high prices Apple would charge. Just now it’s e-bikes and Trek/specialized/transition is the “man”.
 

TCFlowClyde

Active member
Feb 26, 2022
1,335
863
Mesa, AZ
Hopefully the M820-75 firmware is tight. But you never know with Bafang. 😁

BTW/ Mike_Kelly is our resident EE/CE science guy. He appears to be friendly so far🤞

Screenshot_20230314-212113.png
 
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mike_kelly

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Subscriber
Aug 11, 2022
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US
The only thing that gives me hope is that Bafang has been working with Forestal for a long while on their version of this engine. So we may have pretty debugged software by now.
 

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