Focus Jam2 battery/charger group buy.

[sdcoffeeroaster]

I still see these batteries for sale on Craigslist. This $1000. price includes three jam2 batteries, two 4.5A chargers and 2 complete wiring harnesses. Batteries typically can have a 10 year shelf life if left in the 40% state of charge. I now have 3090 miles on my 2018 Focus Jam2 C ebike. I think I might be seeing some slight charge reduction of maybe 10%, not too bad yet. But I'm thinking about the future and wondering if it might be a good idea to pick up a spare battery. I don't see any batteries available in the states although maybe former Focus dealers can still get them but I'm betting they will cost $1000. each or more. All other parts besides maybe the frame can be replaced easily to keep our Jam2 bikes going for a long time. While the battery might last 6-8 years, it will probably lose some ability to charge and the already skimpy range will be reduced even further. Is anyone in the states interested in going in on a 3 way split on the craigslist buy. I think these are being sold by a former dealer here and I can find out more if anyone is interested. thanks

 

[Cbmojo]

I have a jam2 what the process to replace the battery...remove the motor?

 

[sdcoffeeroaster]

I have a jam2 what the process to replace the battery...remove the motor?

Yes you need to remove the motor and to get at all the motor mounts you'll need to at least remove the chainring. Unplug the electrical connections to the motor on the left and put them back in the same sockets when you reassemble. Pay close attention to how the cables are routed, which ones are left and right top and bottom around the battery. I did a frame swap and took pictures but they didn't capture this and I had a difficult time routing things back in especially the main wiring harness. I still am not sure it's perfect but no issues after over 1000 miles. I did buy a special socket for the motor but it was not necessary, just take off the 4 chainring screws to remove that. You might want to take the right crank arm off to get the chainring out of way to make it easier but that's not necessary. the only cable that is routed under the motor is the dropper post cable. Shifter and back brake are zip tied to the top of the frame above the motor. I think I probably put the battery in and out a dozen times before I was finally satisfied with all of the routing...mostly satisfied anyway, lol. 12.5 n-m torque for the motor mount bolts when you re-assemble.

Oh what are you going to do with the old battery? I love to get my hands on one to see if a company in LA can rebuild it.

 

[Cbmojo]

Many thanks...I am not there yet but I am just preparing for the inevitable...seems pretty straight forward

 

[sdcoffeeroaster]

Many thanks...I am not there yet but I am just preparing for the inevitable...seems pretty straight forward

Yes it was not as tough as I thought. It still took me a couple of days to swap out the entire frame but lots of that was just trying to get the battery in correctly. As you tighten it down it gets pulled to one side of the frame and if you have cables in the way they could get pinched.

 

[Gspot]

Why did you swap frames? Still have the old one?

 

[sdcoffeeroaster]

Why did you swap frames? Still have the old one?

The decals on the top tube of my carbon frame were all cracked. Lots of areas were almost brown instead of black and I think the bike sat in the dealers window in San Dimas for a bit. It was replaced under warranty but they wanted to charge me $240. to do the swap so I did it myself and they did require me to return the frame too. The new frame is perfect, dark black and no decal cracking.

 

[Gspot]

Oh ya that sucks. Well good learning experience I guess. I may get a bike with an e7000 and swap it to the wife's bike someday. Always looking. I think her XS BOLD2 would be fine with the smaller motor. We have had bad luck off-road. One snapped chain, torn sidewall, and bad crash has put her off.

Wouldn't mind having a backup battery or two. What are you wanting off Craigslist? I would take 2 batteries and a loom or two? LMK

 

[sdcoffeeroaster]

Oh ya that sucks. Well good learning experience I guess. I may get a bike with an e7000 and swap it to the wife's bike someday. Always looking. I think her XS BOLD2 would be fine with the smaller motor. We have had bad luck off-road. One snapped chain, torn sidewall, and bad crash has put her off.

Wouldn't mind having a backup battery or two. What are you wanting off Craigslist? I would take 2 batteries and a loom or two? LMK

Yeah had my own bad crash on my Giant Anthem, broken collar bone, two ribs and multiple breaks on should blade. Then I got frozen shoulder. It will never be the same of course but tolerable now. The other shoulder is acting up too, impingement, lol. Can't win.

I wouldn't mind picking up one battery and a wiring harness to be able to keep it charged up a bit until I need it. There are 3 batteries, 2 chargers and two wiring looms for $1000. I have not asked him if he is firm about the price. I would like to get the one battery and loom for maybe $300. unless he comes down in price. I send him a message and see. What part of the world are you in? San Diego CA for me.

 

[Gspot]

I live in WA. How would you charge it?

 

[sdcoffeeroaster]

I live in WA. How would you charge it?

You would need an extra wiring harness to hook up to the spare battery and then the charger should work...maybe. You probably would only have to charge it every year or so and they recommend storing li-ion batteries at about 40% charge. You might have connect the harness up to the display to get it to charge...not sure about this part.

 

[Gspot]

Yes the loom would have to connect to the leads off the charging port. Maybe a BMZ 27787 would work?

 

[sdcoffeeroaster]

Yes the loom would have to connect to the leads off the charging port. Maybe a BMZ 27787 would work?

View attachment 35845

I think the loom includes the charging port wiring.

 

[Gspot]

Definetly count me in.

 

[Gspot]

Any news?

 

[sdcoffeeroaster]

The seller is firm on the price. And I got to thinking that by the time I need a battery these batteries might be 6-8 years old and I'd be better off trying to buy one with newer batteries. If I needed a battery today that might be different. I'm figuring my battery will at least last 6 years or more and I can always lower the assist to compensate for a weaker battery. By then I'll probably be in the market for the latest ebike which will weigh 30 lbs, lol.

 

[ENMTB]

I am interested in that deal, just need it then shipped to aus

 

[sdcoffeeroaster]

I just checked and he has increased the price to $1200. Since I made a DIY 250 wH range extender I'm not really looking for a battery anymore, sorry. But here is the new link:

Focus jam2 bold2 electric mountain bike parts - bicycles - by owner... (craigslist.org)

 

[savas]

Hi Guys,
i am interested as well for one or 2 batteries.I got a frame focus jam without motor and defect battery.I have a brand new hardtail with shimano motor and i am thinking to convert the whole bike.One question, is there a problem with these chargers or they are fine?

Happy New Year!!!

Greets

Sava

 

[sdcoffeeroaster]

Hi Guys,
i am interested as well for one or 2 batteries.I got a frame focus jam without motor and defect battery.I have a brand new hardtail with shimano motor and i am thinking to convert the whole bike.One question, is there a problem with these chargers or they are fine?

Happy New Year!!!

Greets

Sava

Since that ad expired here is the new one. Since I build a DIY range extender I'm not too worried about my battery. This is in San Diego CA. Focus jam2 bold2 electric mountain bike parts - bicycles - by owner... (craigslist.org)

 

[Ritz]

Since that ad expired here is the new one. Since I build a DIY range extender I'm not too worried about my battery. This is in San Diego CA. Focus jam2 bold2 electric mountain bike parts - bicycles - by owner... (craigslist.org)

Hi mate, can u make me a diy extender?

 

[sdcoffeeroaster]

Hi mate, can u make me a diy extender?

So the only difficult parts are really wiring a Rosenberger plug to a XT 60 connector. Two large gage wires soldered together for power. That way you can connect to a standard hoverboard battery that typically has an XT60 connector. Then you need to get some sort of housing for the battery and a carrier of some sort to secure that to the down tube. I've posted the soft pack I found on Amazon. The harder part is probably making a custom aluminum carrier. I bent mine from a flat piece of 0.050" aluminum I bought from mcmastercarr using std hand tools, files and sand paper. You also can buy an inexpensive 42v charger and wire another xt60 connector to it for charging your pack at a 2A rate.

As you can see I've evolved my packs a bit and I even built my own 1/2 size pack you can see at the back (had to buy spot welding equipment for that and learn). Lots of options and probably too much liability to build this for someone else. So I've provided lots of information in this thread to help others in their efforts. Key of course is finding a well built battery pack. For the larger pack I bought it from fullbattery.com for $129.

 

[Ritz]

So the only difficult parts are really wiring a Rosenberger plug to a XT 60 connector. Two large gage wires soldered together for power. That way you can connect to a standard hoverboard battery that typically has an XT60 connector. Then you need to get some sort of housing for the battery and a carrier of some sort to secure that to the down tube. I've posted the soft pack I found on Amazon. The harder part is probably making a custom aluminum carrier. I bent mine from a flat piece of 0.050" aluminum I bought from mcmastercarr using std hand tools, files and sand paper. You also can buy an inexpensive 42v charger and wire another xt60 connector to it for charging your pack at a 2A rate.

As you can see I've evolved my packs a bit and I even built my own 1/2 size pack you can see at the back (had to buy spot welding equipment for that and learn). Lots of options and probably too much liability to build this for someone else. So I've provided lots of information in this thread to help others in their efforts. Key of course is finding a well built battery pack. For the larger pack I bought it from fullbattery.com for $129.

View attachment 57899

Thanks for the info mate, but that too much for me and will leave it to the pros.. i’ll keep looking for 2nd hand ones..
cheers for time..