• Warning!!

    Riding a tuned or deristricted EMTB is not a trivial offence and can have serious legal consequences. Also, many manufacturers can detect the use of a tuning device or deristricting method and may decline a repair under warranty if it was modified from the intended original specification. Deristricting EMTB's can also add increased loads for motors and batteries. Riding above the local law limit may reclassify the bike as a low-powered bike, requiring insurance, registration and a number plate.

    Be aware of your local country laws. Many laws prohibit use of modified EMTB's. It is your responsibility to check local laws. Ignoring it, has potential implications to trail access, and risk of prosecution in the event of an accident.

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New Bosch CX 2020 derestricting

JSQ

Member
Jan 28, 2020
28
40
Finland
I found that the old motor tailed off from 15.5 to about 17mph and then was in full on treacle mode. The 2020 CX stops assisting dead on 15.5mph but is less treacle-like over the limit.
On my Rail it stops at around 26,3 km/h (according to the Purion display). I think the 2020 CX is easier to pedal without assistance than the Levo is.
 
Dec 18, 2019
115
53
UK
Interested in this article, as i'm looking at the new 2020 Level R and the new Heckler, as they run nice and big for taller riders. Got a test ride next weekend on the Heckler, but thought i'd pass on my observations on the Gen 4 CX, which I test rode on a Whyte 150 a while back. Now, i've not ridden a previous generation Bosch, but I did find that the motor felt like riding through treacle on flowing singletrack, which I hit on my normal bike around 17/18mph and I wasn't keen on the noticeable cut off. I'll be interested to see how the Shimano compares, as it's quite easy to change the settings on it, via an app, and tell the motor it's in the USA when you're still in the UK. I think this is a good solution, as I don't really want to ride techy/flowing singletrack any faster than my usual 17/18mph anyway. Also, staying under 20mph isn't exceeding Shimano's guidelines for their motor, as it's fine for the USA and Canadian markets.
I'd also ask if anyone's experienced any problems going back to your Bosch/Bike dealer with your derestricted motor, as derestricting it would alleviate the treacle issue I experienced?
 

Doomanic

🛠️Wrecker🛠️
Patreon
Founding Member
Jan 21, 2018
8,700
10,337
UK
There seems to be a lot of people riding the Gen4 that need to man the fuck up... :ROFLMAO:

Having owned a bike with the previous motor I can assure you that most of what you're feeling over the limit or switched off is the weight of the bike, not drag above from the motor.
 
Dec 18, 2019
115
53
UK
There seems to be a lot of people riding the Gen4 that need to man the fuck up... :ROFLMAO:

Having owned a bike with the previous motor I can assure you that most of what you're feeling over the limit or switched off is the weight of the bike, not drag above from the motor.

Man up!!!???:mad::LOL:

I'm 1.98m, 107kg's, 54yo and have been riding unassisted mtb's since '87. This will be my first foray into the world of e-mtb's, as i'm starting to find the big hills, on longer rides, increasingly harder to ride.
With the advent of bigger and longer e-mtb's in XL and XXL sizes, the market is finally beginning to cater for the taller riders out there.
I don't have oodles of cash to be spanked on a new bike, so I need to get this right. My thanks for your advice and experience of the current and previous gen motors, as I don't have that background to draw upon. The Bosch in a Level R benefits from the 625ah battery, so it's one of my top choices, but the geo on the Heckler looks like it may well fit me better, but then I end up being a big rider on a 500ah battery. Each have their pro's and their cons but, in my limited experience, the motor cut off at 15.5mph is a con and 20mph would be far more user friendly in the UK and EU. To that end, the current Shimano would appear to suit my needs, but any advice and/or experience of people riding/derestricting the Gen 4 CX would be greatly received.
 

PhilBaker

Well-known member
May 6, 2020
333
410
East London/Kent
That's EXACTLY what I want to do, but as far as I can tell it requires a Bosch service rep to upload the new SW version and the UK reps don't have login access to the US site to get the software.

If anyone knows a way you would make my day as that's all I would like, but at the moment I don't know a way to get the US software uploaded :-(
 

PhilBaker

Well-known member
May 6, 2020
333
410
East London/Kent
Not sure any of them definitely work on the gen 4 motor. Seems to be mixed reviews of success over longer distances and 504 errors with limp mode engaging.

Looked at Badass, Volspeed 3 and Speedbox 3.0 and reports seem to be inconclusive...
 

Beekeeper

🍯Honey Monster🍯
Aug 6, 2019
1,751
2,197
Surrey hills
Not sure any of them definitely work on the gen 4 motor. Seems to be mixed reviews of success over longer distances and 504 errors with limp mode engaging.

Looked at Badass, Volspeed 3 and Speedbox 3.0 and reports seem to be inconclusive...

Speedbox seem to be a pretty decent company. I heard that after a ride you have to leave the bike on until a countdown on the display goes to zero. I believe that the Speedbox 3.0 allows you to set the max speed cut off and is supposed to work with Gen 4 motor
 

PhilBaker

Well-known member
May 6, 2020
333
410
East London/Kent
Thanks Darren, couple of questions if I may.

- How hard/fast do you tend to ride with it?
- What maximum speed do you set?
- Do you turn off the speedbox/higher speed as you cruise home (ie letting the SW "cooldown" (figuratively) before you reach home and turn it off?
- Or do you just ride with it on constantly and just obey the countdown timer before shutting down?

Just went to get one on Amazon and the 1st review that comes up from April says it doesn't work, so I'm trying to piece together what are the ingredients that make it work vs generate limp home mode...

 

Beekeeper

🍯Honey Monster🍯
Aug 6, 2019
1,751
2,197
Surrey hills
My theory on how the Gen 4 derestriction works is there may be GPS unit inside which samples true distance moved and it compares this data to number of pulses received from speed sensor. A derestrictor will reduce number of pulses by x2 or x4
If the number of pulses is too low for distance travelled (which is a simple calculation based on wheel size. The algorithm will assume you are not running wheels twice or four times the size of a 29inch ?)
The derestrictor will then have to make up those ‘lost’ pulses and send them to the motor after your ride before you are allowed to turn the bike off (hence the countdown at the end)
This is only my theory by the way.
 

Darren66

Member
Mar 7, 2020
130
91
uk
does this speedbox make your bike Unlimited? or 20Mph Darren?
It will theoretically still allow the motor to assist upto 61mph (99kph) but obviously most bikes are geared to spin out at 25-30mph, it does allow you to set your own cut off speed, I set mine at 25mph.
 

Darren66

Member
Mar 7, 2020
130
91
uk
Thanks Darren, couple of questions if I may.

- How hard/fast do you tend to ride with it?
- What maximum speed do you set?
- Do you turn off the speedbox/higher speed as you cruise home (ie letting the SW "cooldown" (figuratively) before you reach home and turn it off?
- Or do you just ride with it on constantly and just obey the countdown timer before shutting down?

Just went to get one on Amazon and the 1st review that comes up from April says it doesn't work, so I'm trying to piece together what are the ingredients that make it work vs generate limp home mode...

I don't ride much harder with the Speedbox fitted, it just allows that bit extra cruising speed, I don't tend to ride much over 18-20mph I find that extra 5mph makes all the difference and as I have set tha max at 25mph, it's still pulling if I want a little extra.
I tend to switch the Speedbox on as soon as I get on the bike, I'm sure that if you don't exceed the original 15mph, you don't get any countdown when the Speedbox is on, this is obviously not normally the case and on a usual 15-20 mile ride, I've only seen a countdown of one and a half minutes, people really get concerned about this procedure at the end of a ride but it's no big deal, just enough time to get into the house and get the garage keys to put my bike away, I've never tried it but some claim that if you forget and switch off mid countdown, it will just continue when you next switch on.
Trailwatts, on here sells them, he is an authorised distributor and you won't find one cheaper.
As for any negative reviews, I can only assume it's down to user error, I think it's possible to fit it incorrectly, into one of the light sockets instead of speed sensor input, though it's quite evident where it goes, I also think that some people fitting these actually think their bike will see 60mph, whereas in reality it will only go as fast as their legs allow.
 

Beekeeper

🍯Honey Monster🍯
Aug 6, 2019
1,751
2,197
Surrey hills
It will theoretically still allow the motor to assist upto 61mph (99kph) but obviously most bikes are geared to spin out at 25-30mph, it does allow you to set your own cut off speed, I set mine at 25mph.

This new limit of Approx 60 mph suggests that the box is reducing the frequency of pulses from the sensor by 4 and feeding this new info to the motor
 

PhilBaker

Well-known member
May 6, 2020
333
410
East London/Kent
Actually, one more question Darren, do you have v 1.0.2 or v1.0.3 on your bosch motor? Whilt my bike is brand new it has the older 1.0.2 software on it which some reviews have said can generate the 504 error.

I think you hold down + and - as you turn it on and it shows the version if you haven't looked before.
Thanks!
 

Darren66

Member
Mar 7, 2020
130
91
uk
Actually, one more question Darren, do you have v 1.0.2 or v1.0.3 on your bosch motor? Whilt my bike is brand new it has the older 1.0.2 software on it which some reviews have said can generate the 504 error.

I think you hold down + and - as you turn it on and it shows the version if you haven't looked before.
Thanks!
My bike was bought new in Feb, it has 1.0.2, according to Speedbox, the firmware version is not an issue.
 

DaveBailey

Member
Jun 2, 2020
5
13
UK
A Whyte E-150 with a Purion display.
Installation takes 2 minutes.
Yes, you should wait with turning off the bike according to the instructions.
Hi Matthew
Do you have any photo's of the install on the Whyte bike, when I looked it seemed too tight to get anything else under the cover?
Many Thanks,
Dave
 

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