Mongoose Envoy

stanmiller

Active Member
For those looking to do a custom build, the Mongoose Envoy is an excellent choice. In November 2019, I converted my Envoy to an eBike with a 500W Bafang hub kit from Bluenergy. I’m now at 1200 miles.

1_stanmiller_mongoose_envoy.jpg


You’ll find other Envoys converted with mid-drives, but I chose a hub to maintain the tractor-trailer-like gearing. Even without battery power, the bike remains very pedal friendly on the smallest chainring with a 22x34 ratio yielding 17.36 gear-inches of go. The bike will walk up a hill.

4_stanmiller_mongoose_with_bags.jpg


Today, the Envoy is only available through Amazon. The price fluctuates between the $700’s down to the upper 500’s. So if you monitor the listing you can catch a deal. I would budget $1500 for the bike plus conversion. Then you can upgrade other bits from there.


The first tweak was the kickstand, swapping the wobbly OEM stand for a Ergotec Double Flex 3. Parked, it’s now on solid footing.

2_stanmiller_ergotec_kickstand.jpg


I recently upgraded the drivetrain to a 9-speed Microshift Advent shifter/derailleur combo increasing to a 27 speed. With Advent, I can go up to a 42t rear cog giving even more climbing ability.

The list of upgrades with links follows.

Links

Ergotec Double Flex 3 Kickstand

Bluenergy: BAFANG Rear Wheel 500W 48V Hub Motor with SW102 Display

TRP HY/RD Road Hydraulic Disc Brake Caliper Black with Rotor

MicroShift ADVENT Right Trigger Shifter 9 Speed w/bearing

MicroShift ADVENT Rear Derailleur - 9 Speed w/ Clutch

Satori Animaris Bike Bicycle Suspension Shock Seatpost - Mountain Bike or Road Bike 27.2x350mm

Sun Ringle Rhyno Lite XL Rim 26"
 

Attachments

  • 3_stanmiller_gearinches.jpg
    3_stanmiller_gearinches.jpg
    51.2 KB · Views: 584
  • 5_stanmiller_mongoose_right.jpg
    5_stanmiller_mongoose_right.jpg
    337.4 KB · Views: 1,736
Last edited:
Wow, a $700 stretch cargo bike? the step over frame is not for me but the gear ratios and carrying capacity are. I can get up 15% grade with 60 lb groceries, 310 lb gross, without power, so I'm not sure I would want to go slower than 1 mph. I have 32:32 lowest ratio, 52:11 tallest ratio. Usually by June I can climb 15% in 32:28.
 
The Envoy is very good at being an electric and non-electric cruiser. You can ride powerless with much of the electric bits still attached.
I take the battery off in winter & hide it under a heat pad in the garage. I leave the motor & controller on, that 5 lb is nothing compared to the 60 lb groceries I haul home from the store. Didn't miss a weekly supply run last winter; there wasn't much ice or snow.
 
I take the battery off in winter & hide it under a heat pad in the garage. I leave the motor & controller on, that 5 lb is nothing compared to the 60 lb groceries I haul home from the store. Didn't miss a weekly supply run last winter; there wasn't much ice or snow.

I ride through winter and charge/store the battery in a warm dry place - typically in the garage but other times the kitchen on the tile floor.

And it's amazing how capable these cargo bikes are be that from Yuba, Surly, Mongoose and others. Who knew? When first converting to electric, my intention was drop down to a single chain ring. I'm glad I didn't and kept the 42/32/22 configuration.
 
Last edited:
Although not a cargo bike, my Mongoose was an excellent conversion candidate. With the 500w motor it easily climbs steep hills and it is very light. I can still ride it without the battery, but choose not to although I sometimes turn off the assist. During winter, I don't ride below 50°, which is the norm.
Mongoose.JPG
 
Last edited:
Although not a cargo bike, my Mongoose was an excellent conversion candidate. With the 500w motor it easily climbs steep hills and it is very light. I can still ride it without the battery, but choose not to although I sometimes turn off the assist. During winter, I don't ride below 50°, which is rare.
View attachment 51208

Nice bike. Fifty used to be my cut-off as well. Then I discovered those disposable hand and feet warmers. I buy them by the box and tuck a pair into my gloves and shoes for rides below 50° F.

And if it's in the 30's, I'll pedal a mile or two unpowered to get warmed up before turning things on.
 
Wow, a $700 stretch cargo bike? the step over frame is not for me but the gear ratios and carrying capacity are. I can get up 15% grade with 60 lb groceries, 310 lb gross, without power, so I'm not sure I would want to go slower than 1 mph. I have 32:32 lowest ratio, 52:11 tallest ratio. Usually by June I can climb 15% in 32:28.

The 32:32 ratio yields 26.01 gear-inches which still is higher than where you want to be for hill climbs under load. At least according to this author. He suggests 19 or lower.

Granny Gear Inches: Ride Now, Save Your Knees For Later
https://bikepacking.com/plan/granny-gear-inches/

In the meantime, I completed the upgrade to the Micro Shift Advent group set with a 11-42T cassette.

6_stanmiller_microshift_advent_1142t_cassette.jpg


It's ridiculous. The 22x42 combo yields a knee-friendly 13.89 gear inches at 2.82 mph.

I joked with a couple walking the hill ahead, "I would ring my bell warning of my approach, but I don't think I can catch up."
 
Last edited:
I can pedal me + 60 lb groceries up 15% usually at 32:28. 32:32 is only for first couple of rides in the spring when I'm wimpy.
Weighed the bike today after a grocery run. 180 lb rear, 40 lb front. I'm 180 with shoes clothes & winter lard. So gross weight 400 lb. In town pretty flat, but didn't use the power into a 15 mph wind.
Would ride out to camp today, but waiting on a building supply I ordered from stock @ the Lowes 6 miles away last Monday. It will be delivered next Monday. @#%^$*&
 
Last edited:
I just got my Envoy yesterday and finished the final assembly. I plan to e-assist it but I just don't know whether I should do a hub motor like the o.p., or a mid-drive. I have done much more research on the mid-drive. I like torque sensing and a TSDZ2 has torque sensing built right in. A hub drive with torque sensing means scrapping both the OEM bottom bracket and the OEM rear wheel. Would I be right in thinking (hoping) that 'chainline' issues with a mid-drive is not as much of a thing on the Envoy with that long chain run? I think I want at least double chainrings so I can leave the battery home some (short) trips or a triple to limp home in lower gears if the need arises on a longer trip.
 
If you have a geared hub motor you don't have to drag the motor with your feet when the electricity fails. If the chain fails with electricity you don't have to stop and repair it right then - if you have a throttle. there are torque sensing brackets for hub motors now. My throttle quit in a heavy rain & I pedaled on 28 tough miles at about 8 mph (January, I was out of shape).
 
Soon I'll be crossing 3000 miles ridden.

Recently, I had been getting noise from the rear hub motor. I pulled the motor cores from the Envoy and my Electra Townie (both Bafang SWX02) and noticed the motor gears on the Envoy were more rounded. This motor had started in the Townie for 2000 miles and then moved to the Envoy. I swapped the newer Townie core into the Envoy and the noise stopped. Next is to replace the gears/clutch in the noisy motor.
 
Soon I'll be crossing 3000 miles ridden.

Recently, I had been getting noise from the rear hub motor. I pulled the motor cores from the Envoy and my Electra Townie (both Bafang SWX02) and noticed the motor gears on the Envoy were more rounded. This motor had started in the Townie for 2000 miles and then moved to the Envoy. I swapped the newer Townie core into the Envoy and the noise stopped. Next is to replace the gears/clutch in the noisy motor.
I wore out the gears on the ebikeling geared hub @ about 4500 miles. I pedal unpowered a lot, maybe why mine lasted longer. Made a grunch noise, then it wouldn't roll backwards anymore or pull forwards. Fortunately it was fine to pedal home 15 miles. Would like to buy new plastic gears, but probably none available for an off-brand motor.
 
Tomorrow I'll be over 3500 miles on the Envoy. A lot has changed since the beginning of the project. All that remains of the original bike are the frame, handlebars, crank, and a few odd bits. More details to follow...
 

Attachments

  • 1_stanmiller_envoy_3500_miles.jpg
    1_stanmiller_envoy_3500_miles.jpg
    167.9 KB · Views: 444
I'm at about 6000 miles on the yuba bodaboda. Chain, brake pads, tires, power wheel+controller+throttle, seat, handgrips have changed. Rest is original, including battery. Oh, the bell broke.
 
@EMGX - I thought the same thing, but I knew, on sight, that the Envoy was worth having. So I GAVE away a pristine Raleigh Team USA, a Schwinn World Tourist project, and another more recent Schwinn that was still from when Schwinn was a frontline brand. I still have a fleet of seven, including the Envoy. I rode it for awhile unpowered and the "tractor-trailer like" gearing as described by an earlier poster is dead on. The saddle is amazing. The 2.4" tires roll way better than I expected. I have a TSDZ2 in the BB and I bought a 104bcd adapter. I haven't decided on rings but I am considering 32/46. Sadly no one makes an adapter with a 64bcd granny carrier so 32T is the lowest one can go. I bought a rectangular format battery from EV3EM to fit in that open space behind the downtube. Allowed me to keep the frame mounted front rack I had bought.
 

Attachments

  • Envoy profile.jpg
    Envoy profile.jpg
    1,014.3 KB · Views: 1,111
@EMGX - I thought the same thing, but I knew, on sight, that the Envoy was worth having. So I GAVE away a pristine Raleigh Team USA, a Schwinn World Tourist project, and another more recent Schwinn that was still from when Schwinn was a frontline brand. I still have a fleet of seven, including the Envoy. I rode it for awhile unpowered and the "tractor-trailer like" gearing as described by an earlier poster is dead on. The saddle is amazing. The 2.4" tires roll way better than I expected. I have a TSDZ2 in the BB and I bought a 104bcd adapter. I haven't decided on rings but I am considering 32/46. Sadly no one makes an adapter with a 64bcd granny carrier so 32T is the lowest one can go. I bought a rectangular format battery from EV3EM to fit in that open space behind the downtube. Allowed me to keep the frame mounted front rack I had bought.
Don't tempt me. Nice bike.
I bought a 36v 500w TSDZ2 to put on my wife's Dahon Briza and I tested out the same motor on a Dahon Jack. Very nice kit and easy to install on the Jack, less so on the Briza which required some frame modifications but it still wasn't difficult. It came with the standard 42t dished chainring as well as a flat 34t chainring which I think is the smallest that will fit on the standard spider. I stuck with the dished chainring because the smaller flat sprocket would have been a problem with chainline on the largest rear cog as well as rubbing on the inside surface of the chainstay when on the smallest rear cog. Overall it works great for her on the Briza and is a relatively powerful and refined motor in my opinion. On the Envoy I don't think that I would want to give up the triple chainring with the super low gearing. Currently I'm installing a 48v 500w (possibly 1000w peak as the controller has a peak of 22a) rear hub motor on an old Schwinn Sierra bike that I have. Depending on if I like that setup I actually would consider installing it on an Envoy which looks like a nice bike for doing some multi day camp and ride touring this spring and summer. It has enough space to carry everything I would want to bring. I did some touring on a Yamaha powered gravel bike (and a regular non-assist bike) last summer/fall but the gravel bike doesn't have the frame to really handle bigger loads well.

DSCF0748.JPG
 
As we speak, the Envoys are getting harder to come by. The medium/large model has been sold out for some time and the small/medium is now priced above $800 on Amazon. :(
 
Back