Focus jam 2 complete wiring loom

Russ

New Member
Feb 10, 2019
26
34
Perhshire
Removed the complete wiring harness from the jam last night to check for continuity of the various wires , I had to satisfy myself that no fault existed with the loom it's self, all check out ok.
However, all the wiring that comes out of the battery about 3" latter disappears into a black rubbery lump of silicone like material.
I picked all this apart, my biggest surprise here was nothing is soldered together, only crimped.
The thin wiring joints had heat shrink insulation , very good, but the heavy black and red cables ( the main current carrying cables !)
have no insulation!! Only separated by the silicon like material. Fair enough the are not touching , l would soon be aware of it if they did!!,
It's hardly a well executed design?
I'm just pedantic when it comes to doing things properly .
Henry Royce (one half of Rolls Royce) once said "whatever is rightly done, however humble, is noble"

Russ.
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Russ

New Member
Feb 10, 2019
26
34
Perhshire
Fascinating to know, what was the problem that triggered this action? What were the symptoms?
The bike no longer switched on Steve , dead , as dead as the parrot on the Monty python sketch!
Appears to be faulty battery management system , charger and on off switch can't see the battery because the BMS says no!
Trying to source another battery ,
Contacted focus direct , they won't sell me one, they say I will have to get one through a bike shop, hopefully this is in hand.
I've had to go back to my clockwork bike at moment, bloody hell seems like such hard work compared to the focus!
Russ
 

bissona

Active member
Patreon
Oct 14, 2018
137
106
Guernsey
The bike no longer switched on Steve , dead , as dead as the parrot on the Monty python sketch!
Appears to be faulty battery management system , charger and on off switch can't see the battery because the BMS says no!
Trying to source another battery ,
Contacted focus direct , they won't sell me one, they say I will have to get one through a bike shop, hopefully this is in hand.
I've had to go back to my clockwork bike at moment, bloody hell seems like such hard work compared to the focus!
Russ
We had exactly the same. Replaced everything except the battery and it turned out to be the battery... Sourced one from a dealer in France, but only because we were down that way. Good to see what's inside that black lump, we had wondered!
 

Gasser

Member
Feb 6, 2019
39
18
Sidmouth Devon
Ah, I've had the "not switching on" problem as well. Been back to my local dealer who first did a general condition check and updated the firmware, but was still the same afterwards. So then focus sent out a new switch, still no joy, so finally Focus sent out a complete loom, which was installed Friday and finally the bike came back to life, so hopefully solved.

I've not had a chance to test properly, but my symptom were, after a ride and a long full charge the bike wouldn't switch on after being left a few days. At first it would take a few switches and then switch on, or hold the switch on for a minute then try again. But finally I was having to put the charger back on, leave changing for a minute of so then disconnect and it would switch on.

Then fortunately when at the shop it wouldn't switch on at all, so now that it does hopefully cured, will report back
 

Akiwi

🐸 Kermit Elite 🐸
Feb 6, 2019
986
1,286
Olching, Germany
Sounds very similar to the problems I was having with my Focus Jam. It would Intermittently not turn on. Funny thing was If I shook the bike then sometimes the on button would gloww blue, then go off again.

After 7 times in for repair, my dealer sent it back to the factory where they apparently replaced everything. I got it back after 7 weeks, and then when I turned it off, it would go into a cycle of turning itsself on and off, draining the battery.
I took it back to my dealer and gave them the bike back.
Interesting to see the thing totally dissasembled. I opened mine up to see if I could see anything. All I could see was a total birds nest of wires going everywhere and as it was still brand new and under guarantee, I decided not to touch it.
 

Gasser

Member
Feb 6, 2019
39
18
Sidmouth Devon
Funny enough, when I picked it up yesterday from the dealer (Big Peaks, awesome guys, can't recommend them enough) they said they questioned the Focus rep about whether there had been other reported issues with switching on, and guess what his answer was , no know reports, so someone is not telling the truth, as I've also seen reports of the same thing on the Facebook group.
 
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OldBean

E*POWAH Elite
Patreon
Apr 28, 2018
602
528
East anglia
Trouble is although the Focus is “German Engineered”. It is made in China where quality control is not so good.....be good to find which brand is the most reliable......someone better than me at polls should start one.
 
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Russ

New Member
Feb 10, 2019
26
34
Perhshire
Trouble is although the Focus is “German Engineered”. It is made in China where quality control is not so good.....be good to find which brand is the mosr reliable......someone better than me at polls should start one.
Exactly
The bike it's self is good, the shimano motor seems good, but the Chinese made battery seems to be a weak link ( the battery has a made in China sticker on it!)?
Russ.
 

dirt huffer

E*POWAH Master
Dec 3, 2018
312
312
Minneapolis
I can understand why everything is crimped for mass production but those crimps look particularly shoddy

Exactly
The bike it's self is good, the shimano motor seems good, but the Chinese made battery seems to be a weak link ( the battery has a made in China sticker on it!)?
Russ.

The biggest problem with eBike batteries in general is the BMS. There are so many poor examples of this. One of the reason why I wish manufactures would have ditched it for a balance charger. Balance charging is so much more reliable and safer IMO
 

Russ

New Member
Feb 10, 2019
26
34
Perhshire
I can understand why everything is crimped for mass production but those crimps look particularly shoddy



The biggest problem with eBike batteries in general is the BMS. There are so many poor examples of this. One of the reason why I wish manufactures would have ditched it for a balance charger. Balance charging is so much more reliable and safer IMO
So true !
But If they made it to reliable , i guess then the manufacturers would be less likely to extract more money from us when the crap BMS system fails !?
 

R120

Moderator
Subscriber
Apr 13, 2018
7,819
9,185
Surrey
My one big takeaway from the past year on they forum, and being lucky enough to try a lot of the bikes out there, is that at this moment in the development of EMTB's and I would suppose Ebikes in general, is that its the brands that don't use the full ecosystem of parts from motor suppliers that have the most problems.

By that I mean that if you look at the brands that just wholesale use the Shimano or Bosch motor, battery etc there seem to be far less problems than those who mate the motors to third party batteries.

If you get the full kit off the manufacturer, you also use their wiring looms and connectors, whereas if you go off piste, you are reliant on getting someone to knock up these bits.
 

OldBean

E*POWAH Elite
Patreon
Apr 28, 2018
602
528
East anglia
My one big takeaway from the past year on they forum, and being lucky enough to try a lot of the bikes out there, is that at this moment in the development of EMTB's and I would suppose Ebikes in general, is that its the brands that don't use the full ecosystem of parts from motor suppliers that have the most problems.

By that I mean that if you look at the brands that just wholesale use the Shimano or Bosch motor, battery etc there seem to be far less problems than those who mate the motors to third party batteries.

If you get the full kit off the manufacturer, you also use their wiring looms and connectors, whereas if you go off piste, you are reliant on getting someone to knock up these bits.

A la Focus ..I am afraid to say.:(
 

Russ

New Member
Feb 10, 2019
26
34
Perhshire
One thing I forgot to mention was if you look at the third picture down , you will see a thin black wire( just above the 2 yellows) with a clean cut end, this was connected to nothing inside the black rubbery block! .
I don't think it's broken off any other wire as the end has a clean cut.
I can only assume that the black multi pin connector it comes from is from another system / bike and wasn't required for use!!
I wonder if focus will supply me with a wiring diagram?! The saga continues
Russ
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
821
520
Derbyshire Dales
Exactly
The bike it's self is good, the shimano motor seems good, but the Chinese made battery seems to be a weak link ( the battery has a made in China sticker on it!)?
Russ.

Chinese battery! that's something I would rather not have known, especially as I am sure that I have read somewhere, possibly on this forum, that the battery was a quality product made in Germany. :confused:
 

Russ

New Member
Feb 10, 2019
26
34
Perhshire
Didn't doubt what you were saying for one moment Russ, just disappointed in what you discovered.
My main experience of Chinese batteries is on night rides when all sorts of problems seem to beset the guys running Chinese produced lights.
Yes I know exactly what you mean, I had a Chinese made light , it would switch itself on and off at random while riding!!
Russ.
 

R120

Moderator
Subscriber
Apr 13, 2018
7,819
9,185
Surrey
Surprised its not a BMZ, as that seems to be the go tot battery for most Ebikes with proprietary batteries.
 

Gasser

Member
Feb 6, 2019
39
18
Sidmouth Devon
Having seen the old loom on the workshop bench, I really would like to strip this new loom down and smoother all the connections with silicon grease to waterproof them all, but then I also don't really want to disturb a working bike....
 
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Mabman

E*POWAH Elite World Champion
Feb 28, 2018
1,048
1,735
Oregon USA
Surprised its not a BMZ, as that seems to be the go tot battery for most Ebikes with proprietary batteries.

Actually it very well could have something to do with BMZ. The fact that it uses LG cells, which BMZ is heavily aligned with LG, and the fact that it is made in China where BMZ has one of the largest battery manufacturing facilities at this time. Derby GMBH is just another branch of PON Holdings, the parent company for Focus, as well as other brands

Screen Shot 2019-02-18 at 12.06.36 PM.png

and perhaps PON just has all their battery/charger designs done under the Derby banner with BMZ input/components? It is a tangled web in the bike industry with Accell and PON etc. having so many pieces of the game in play on the same board, a bit like Monopoly.....There is little doubt though that BMZ has aligned itself to be a major supplier of battery tech/components to the eBike industry.

Of interest aside is that Accell made a play for Derby back in 2011 but ultimately it went to PON. Derby filed bankruptcy proceedings in the US about 6 months after this. Recently PON decided to pull Kahlkoff and Focus from US distribution and will no longer supply the US so apparently the market here is not worth the hassle for them.
 

ggrin

Member
Feb 11, 2019
51
20
Scotland
My bike is 3 months old, it often takes 2 pushes of the switch to get it to come on (always been like that).
I just thought I wasn't pushing switch firmly enough but now I am worrying I might have a problem waiting to develop fully.
I have mentioned the switch needing more than one push to my dealer and he said nothing to worry about.
 

highpeakrider

E*POWAH Master
Aug 10, 2018
685
556
Peak District
My bike is 3 months old, it often takes 2 pushes of the switch to get it to come on (always been like that).
I just thought I wasn't pushing switch firmly enough but now I am worrying I might have a problem waiting to develop fully.
I have mentioned the switch needing more than one push to my dealer and he said nothing to worry about.

After a number of hours the bike goes into sleep mode requiring 2 presses to switch on.

Nothing to worry about.
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
821
520
Derbyshire Dales
My bike is 3 months old, it often takes 2 pushes of the switch to get it to come on (always been like that).
I just thought I wasn't pushing switch firmly enough but now I am worrying I might have a problem waiting to develop fully.
I have mentioned the switch needing more than one push to my dealer and he said nothing to worry about.


I read in the manual, that that is what it is supposed to do.
Mine says to push button briefly and then hold it down for a second time for three seconds.
If on standby, whatever that is, you only have to push it once.
The problem I have is getting the TEC battery to connect when out on a ride, much to the amusement of my clockwork mates..
 

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