Oxygen S Cross CB MK11

Eaglerider

Esteemed Pedelecer
Oct 25, 2011
374
47
East Sussex
Hi all,

After 13 years and 15000 miles on my 2011 Freego Eagle, I bit the bullet and bought a new Oxygen. The Freego is still working very well so I donated it to a relative.

The Oxygen is a great bike that rides very well. It does all I need it to with one exception. The electronics are pants. The vicous cut off at 15.5mph followed by a long delay to re-engage once speed is back below 15.5 means it's difficult to maintain a smooth ride, so as you start an incline the speed drops to about 12mph before the power kicks in. This results in a series of surges as I ride along. Riding on level track with my relative yesterday I was blown into the weeds by a 13 year old Freego. Such a shame Oxygen have ruined a lovely bike.

I've done some research on here and it appears the only fix is a new controller. Can anyone recommend a suitable controller. I'd like to have a throttle again but I'm not bothered about extra speed, so long as it works like the Freego one did such that the 15.5mph power continues and my pedalling is in addition to this rather than instead of the assistance.

Lastly, the sluggish application of assistance makes crossing a busy junction pretty hazardous. Any and all comments appreciated.
 

thelarkbox

Esteemed Pedelecer
Aug 23, 2023
1,252
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oxon
Got any pics of or links to your bike? google suggests a rigid step thru shopper which sounds unlikely to be shifting at speeds over 15 mph comfortably?? (tho i could be letting the limitations of my local rds colour my perception)

A controller upgrade should resolve most of the issues although, checking the bikes top speed with the rear wheel lifted is rumoured to be the #1 check after a visual once over plod is likely to test if pulled over ever?
So set the top speed or not with your eyes wide open.

KT(Ketung) brand controllers are popular for the wide range of compatible display i/o options and the configurable set up, but the chenglish manuals can be a challenge.. sellers like topbikekit supply them in a few different form factors too.

Depending on your bikes current controller and its position/housing and the current cable/flex routing it could be a 1hour job or an all weekend soldering exercise..
 
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saneagle

Esteemed Pedelecer
Oct 10, 2010
7,005
3,241
Telford
We always recommend KT controllers. If you're lucky, you might be able to find one of the small 17A ones, which would be very good for your bike. Whichever one you get, check the size and compare it with your present one so that you can be sure that it fits in the compartment.

Your harness, pedal sensor and possibly brake connectors won't be compatible with a KT controller, so you need to replace the harness, then you have a choice of replacing the pedal sensor or cutting off the connector and soldering the wires. You don't really need brake cut-offs with a KT controller, so you can choose what to do about them. You also need an LCD. Choose whichever you want except LCD1. I recommend getting a throttle too because it can be set up as legally to be a power over-ride switch, which is very useful.

You need a wire puller to pull wires through the channel at the back of the battery. An old bike cable will work or anything stiff and thin enough to push through as a leader, or you can buy a proper one. The one I used was a very thin fibreglass rod with an adjustable loop on the end.
 
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Eaglerider

Esteemed Pedelecer
Oct 25, 2011
374
47
East Sussex
20240820_184326.jpg

2024 Oxygen S Cross CB MK11. I've only had it a week.

I'm pretty clueless with a soldering iron. My plan is to source the right gear, then get a local Ebike chap to install it. I know it's going to void the warranty, but I want the same experience in the cruise that I had with the Freego. Everything else on the Oxygen is great, really strong hill climbing and well balanced handling. I guess I could endeavour to put up with it if I must, but I'm in my 70th year and I want maximum fun, if the issue can be fixed, that's my priority.
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
7,005
3,241
Telford
View attachment 59459

2024 Oxygen S Cross CB MK11. I've only had it a week.

I'm pretty clueless with a soldering iron. My plan is to source the right gear, then get a local Ebike chap to install it. I know it's going to void the warranty, but I want the same experience in the cruise that I had with the Freego. Everything else on the Oxygen is great, really strong hill climbing and well balanced handling. I guess I could endeavour to put up with it if I must, but I'm in my 70th year and I want maximum fun, if the issue can be fixed, that's my priority.
I doubt very much that a local bike shop would do that for you, though you can always try. Don't accept anything other than a KT controller.
 

Eaglerider

Esteemed Pedelecer
Oct 25, 2011
374
47
East Sussex
We always recommend KT controllers. If you're lucky, you might be able to find one of the small 17A ones, which would be very good for your bike. Whichever one you get, check the size and compare it with your present one so that you can be sure that it fits in the compartment.

Your harness, pedal sensor and possibly brake connectors won't be compatible with a KT controller, so you need to replace the harness, then you have a choice of replacing the pedal sensor or cutting off the connector and soldering the wires. You don't really need brake cut-offs with a KT controller, so you can choose what to do about them. You also need an LCD. Choose whichever you want except LCD1. I recommend getting a throttle too because it can be set up as legally to be a power over-ride switch, which is very useful.

You need a wire puller to pull wires through the channel at the back of the battery. An old bike cable will work or anything stiff and thin enough to push through as a leader, or you can buy a proper one. The one I used was a very thin fibreglass rod with an adjustable loop on the end.
Hmm, that's quite alot then, and well beyond my abilities. Perhaps, for the time being, I'll try and get used to it and see how I feel in a month or two. Thank you both for your help.
 

thelarkbox

Esteemed Pedelecer
Aug 23, 2023
1,252
385
oxon
Ok i missed the bike full id in the title and searched for freego oxygen doh!, That bike sure looks more 15mph capable ;)
Yeah, probably not the bike you would have bought if you expected to want to upgrade the control system..
If applicable a return might be worth consideration? if looking to upgrade the control system a bike with a more bolt on look can be both cheaper to buy and easier to modify.

any difference in pas response if you select different power modes?? (page 11 2021 manual).

Try selecting a lower gear for pulling away with? if the initial pedal isnt so hard it might not bug you as much?
dropping the gears just before or when braking to a full stop is a good habit anyway?

- I had issues with my kit conversion pas sensor as it would initially rotate with the crank axle until the power/sensor cable snagged it still, delaying the initial pas response when pulling away. probably not the case with a prebuilt bike but??

No harm in checking your current controller and its form factor, and planning out just exactly what's involved.. when broken down into sequential steps nothing should be too challenging ;)
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
7,005
3,241
Telford
The control system described in that 2021 manual is very user-unfriendly. It has 18 levels of pedal assist, which is very confusing for most users, and all those that I spoke with didn't even understand how it worked. I'm pretty sure that they changed it for a conventional 5 levels one. Can OP confirm which of the two he has?

If it's as described in that manual, the eco, normal and power settings are levels of power that are something like 5A, 10A and 15A. You set it before your ride because it's not easy to change once you're going. Having set the power level, you then have 6 levels of pedal assist that each have a different maximum speed. I don't know whether the upper levels are all the same because it used to go to 24 mph unrestricted. To get the power for 24 mph, you had to preselect "power" as the power setting. You used to be able to change the speed limit, but they fixed it in the software around 2018 and I think they locked the power setting too, but I'm not sure. It's always worth checking.

Edit: I see further down in that manual that they also describe the other LCD.
 

Eaglerider

Esteemed Pedelecer
Oct 25, 2011
374
47
East Sussex
I have 3 power levels, power/normal/eco. These are adjusted within the settings menu, takes about 15 seconds. I've got it on full power setting.
Then, once riding, I have 6 PAS settings which just restrict speed levels progressively. All pretty standard stuff. It's only when cruising on PAS setting 6, cruising on the flat with constant pedalling as well doing around 16 or 17mph. Then it starts this surging on and off. I'm going to persist because I like evreything else about the bike for the time being.
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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I would have kept the Eagle all day long over the Oxygen, I agree the 18 power levels is way too many . The Oxydrive kit from H2 engineering was the same and I only ever used six power levels.

The KT is by far the best replacement system to use.
One simply can't just replace only the controller but also the display and the trunk wiirng inbetween.
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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Three power levels with six PAS levels stiull makes it 18 power levels/settings to use just as the Oxydrive did.
One assumes the Oxygen uses the DAS kit system which is a Lishui speed control system, I remember the Oxydrive was pretty fast it's Bafang CST (300rpm ?) with the 17a controller topped out a tad over 24mph.