New FAT-HS owner with some questions


Well-Known Member
Wanted to pick up ebikes for my wife and I, while considering the general shipping/supply chain situation and nearly everyone out of stock, I found a low-ish mile (160 miles) FAT-HS used a couple of hours away and brought it home.
The bike has some upgrades (carbon fiber stem, dropper seat post, Cloud 9 seat, rear shock replaced with an air shock), but also an issue or two - mainly in missing a kickstand and some derailleur/shift issues.

I've got a list of Qs, some very newbie. First ebikes, but have had motorcycles and wrenched on them + cars for a while..and looking to get everything sorted, etc.

1. The motor is a Bafang 1000W M615 - which corresponds to pretty much no one discussions/comments anywhere. Is this an earlier version of the 'BBSHD' motor? What are the differences vs M620 and 'Ultras'? Manual with parts diagram anywhere?
2. Is there a manual online anywhere for the bike and components (nothing on Eunorau site I've seen)? Looking for deraileur, shifter, fork, motor etc. manuals/whatever can be found. (It has Sunrace shifter and derailleur).
3. Seems like the Bolton Lancer is the same bike, while the Juggernaut FS uses at least the frame - are there other relables of this bike? (Might help me for parts availability in the US..)
4. Is there a way to buy a compatible kickstand for the bike?
5. Is there a clean way to add a skid plate to protect the wiring at the front/bottom of the motor?
6. Are there any options for a rear light that can key into the brakes? (Failing that, recommendation for a rechargeable post-mount light is welcome).
7. Anywhere shipping from the US to get the fenders and rack from?
8. The derailleur hanger was broken and the PO had a nice-looking CNC replacement fit, which may or may not be the source of current shifting blues - I need to get a bike repair stand to really spend more time fiddling with it, but can't get into the lowest gear after first pass adjustments (which is better than it was before, but not 'done') and the handlebar shift lever doesn't seem to remotely read correctly, so:
9.a. Is there somewhere to get a replacement original derailleur bracket? I see biktrix has numerous, but unsure if any are compatible..preferably shipping from the US.
9.b. Any manuals to the derailleur and shifter appreciated.
10. I have the second battery but not the mounting bracket - how/where can I get the bracket and wiring, and is there a recommended charger that can fast charge and limit to 80%/set percentage to charge to? Both batteries are working fine and not positive I want to typically mount the second one yet, still trying to get a feel for actual range once I get the shifting sorted..but considering my wife now has a 500W Bosch bike and leaves it on ECO mode - I may need to ;)
11. Last one - when I go into display settings, there is a mode for battery information (a screen or two) - it seems to not read any values. Should the info come up instantly, does it take some time, or anything I should check out on the wiring?

Thanks in advance!
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Emailed Eunorau - no response there either as of yet..
Eventually got some response that wasn't worthwhile. Did find out no rack/fenders until next year, but on the derailleur hangar first got 'why not buy it from us?' and when I asked HOW/where to buy it - saw no more responses. Never got an answer for how to buy a kickstand replacement. Pretty much got nowhere overall even after bumping the email/support ticket a number of times. Was sent a manual for something - not the FAT-HS - which sort of defeats the purpose, as was really looking for simple things like part #s and actual specs, etc.

For anyone needing to replace the derailleur hanger, after wasting MUCH time, I think I found a match on aliexpress for a 'Himalo 27.5 MTB', 2 for $17 shipped...of course on the slow trip from China..don't have them yet but from the pics, hole placement, as long as what arrives is what's pictured, appears to be a match.

No help on second battery mount plate, battery or bike connector (I have 2x batteries but not the second battery mount plate/cable). Basically - no help.
Meanwhile, was thinking several other vendors use the same frame and had thought one of the Biktrix bikes was. On the plus side, their support was understandable, cheerful, and responsive even though it wasn't a Biktrix bike, but also no parts. Contrast in actually trying to help was night and day.

I aligned the existing hangar and replaced the POS Sunrace derailleur and shifter. Had to flex a bit RE: parts availability, but wound up with a 9spd Deore rear derailleur and MicroShift Shimano-compatible shifter. Cable that came with the Microshift was too short, while the existing derailleur cable had some issues, being twisted up halfway up the cable sheath, but had a spare on hand. Shifting well now, although will likley replace the Microshift shifter at some point - works well but don't like shifting both up and down via thumb.

Was considering going to an 11 speed, primarily because had such a miserable experience retaining the chain with the Sunrace gear pre-alignment and replacement I wanted a rear clutch derailleur, but I'm not convinced an eBike really 'needs' 11 speeds..somewhat considering a Box 8 or 9 in the future (I like to play with and tweak my cars, motorcycles etc), but not sure if the FAT-HS can take a cassette while Eurorau's ads/bare specs mention 'freewheel' but I suspect it's a freehub and they're just calling out the pedal isn't forced forward when moving, but dunno - may pull the rear wheel over the weekend. If anyone's sure, please let me know.

I usually ride around in PAS 3-4 (of 9) and had an 'interesting' experience. We're just getting into ebikes (wife and I), and trying to plot out some reasonable rides leaving from our house, although we do now have a bike rack. We headed out on a ~16 mile ride..everything was more or less OK until heading back. I had left at ~80% charge, so was mostly staying out of higher levels on the way back, then was at around 30% going up a long but shallow hill close to home and the display power just jumped to 0%. Could be battery, could be display - unknown, but was annoying. Shut it off for a few seconds, powered back on, and was reading at ~20%. I think in general the display -> battery interactions simply aren't that accurate. I've seen on other rides cold-start 'claim' of near 100% then once moving in the 80-something % range. Not sure if there's a good way to truly load test the pair of batteries, but the 'extended battery information' screen from the display gets no data - possible it's due to the reprogramming, possibly the battery controller and display are just incompatible - unknown. Asked and never got an answer on that from Eunorau.

Still looking for answers on some of the original Qs, but have pretty much given up on getting any of value from Eunorau. Would be happy to be proven wrong but not seeing it, and their Facebook group responses are similarly poor from what I've seen.

EUNORAU 48V1000W FAT-HS Gearing??​

Hi🙂! I’m trying to compare the EUNORAU FAT-HS vs FAT-HD full specs. Can someone tell me both the EUNORAU FAT-HS (9-Speed) & possibly the FAT-HD (7-Speed) Cassette Gears? (Example: 14 to 34T) please???? Thank you.
Checked quickly - the FAT HS is 11-40T in the rear. Unsure if it's actually a cassette hub/wheel or freewheel as haven't had time to take it apart, but would love to know if anyone already has...
Peace be with you!
Thank you so much for responding. I posed the question Eunorau. Below is their reply:
FAT-HS: 11 TO 34T
FAT-HD: 12TO 28T
BTW, I’d posed the same question to Bolton ebikes about their identical, to the FAT-HS, “LANCER” and was supplied the very same gearing.
May the Lord Bless and Keep You.
Interesting - doubt my rear has been changed but it’s definitely a 40T on the largest rear sprocket. Entirely possible they’re not all usable, or they’re just throwing on whatever parts are at hand as mine had a Sunrace derailleur and shifter vs the Shimano etc. Would still love to know if it’s a freewheel or free hub/will take a normal cassette, just too busy to pull it apart…