Salt water is patient. It works its way past seals, sits in the races overnight, and one morning the motor that used to spin silently has a faint grinding note to it.
Foil assist bearing replacement is the most common piece of maintenance on an electric foil motor. On the Manta side this applied to the first generation TakeOff. It is no longer the case with the Performance motor, which is fully enclosed and has no bearing service interval, but we have kept this tutorial online so first generation owners can do the job themselves rather than send a unit away.
It also applies to most other foil assist and eFoil motors on the market, because nearly all of them use the same outrunner architecture and the same bearing classes.
Mostly, yes. Foil assist motors are outrunners, where the outer case rotates around a fixed inner stator, and the bearing layout is near universal across the category. The removal method, the shaft check and the seating technique below are the same regardless of the badge on the unit.
What changes between brands is the bearing size and the way the motor mounts to the pod. Measure your own bearings before ordering replacements. The number stamped on the old bearing is the fastest way to identify it, and the numbering follows a standard system across manufacturers.
Foil Drive units use an outrunner motor with the same bearing-in-rotor, bearing-in-stator arrangement described here. The removal steps, the M6 bolt method and the socket-press seating technique all transfer directly. Confirm your own bearing designations from the parts you remove rather than assuming they match Manta sizes.
Duotone Foil Assist motors follow the same outrunner principle, so the sequence in this guide applies. As with any brand, check the bearing numbers stamped on the parts you take out, and use the same Loctite retaining approach when fitting the new ones.
The first generation Manta TakeOff motor has three bearings: two 6800 bearings in the rear rotor, available in NSK stainless steel for corrosion resistance or ceramic for lower friction, and one 6900 ceramic bearing in the front, seated deep in the stator close to the motor pod. The steps below were written for this motor.
The method also covers eFoil propulsion motors and home-built foil assist setups using standard outrunners. If the motor has a rotor that slides off a shaft, this guide describes the job. The deep groove ball bearing designations reference is useful for decoding a number you have not seen before.
| Rear bearings | Front bearing | |
|---|---|---|
| Manta TakeOff (1st gen) | 2x 6800 stainless or ceramic | 1x 6900 ceramic |
| Manta TakeOff Evo (Performance motor) | Fully enclosed | Fully enclosed |
| Foil Drive | Check your unit | Check your unit |
| Duotone Foil Assist | Check your unit | Check your unit |
| DIY / eFoil outrunner | Check your unit | Check your unit |
Bearings rarely fail without warning. The symptoms build over a few sessions, and catching them early keeps the job simple.
Nothing exotic. Most of this is already in a home workshop.
Remove all four bolts starting with the hardest one in the left corner.
Pro tip: Cut a 3mm allen key shorter and bend the long end. It makes the job easier.
2x in the rear, visible when you remove the rotor
1x in the front, deep in the stator, close to the motor pod
Option 1 – Use a specialized bearing removing tool (preferred)
Watch this video for removing a bearing with the tool
Option 2 – Use an M6 bolt and hammer
Use a long M6x85mm bolt to remove the old bearings. Make sure to place the bolt end on the bearing, not the bottom lip where the bearings seat. You can flip the motor over to check before tapping both out. They should pop out easily with very little force. For more details watch the video.
Option 3 – Use a wall anchor bolt and plier
Check that the bearings can properly slide into the rotor shaft. If the bearing seems to get stuck it indicates that a part of the shaft has imperfections causing the bearing to get stuck. This is likely due to an uneven surface on the shaft. To resolve this issue, follow the steps below:
1. Sand the shaft using sandpaper (type: 600 CW, then 1500 CW for the finishing).
2. Watch the instructional video: Shaft sanding
Sand the shaft as shown in the video.
Check the bearing fitting.
If still stuck, repeat the process until the bearing fits properly.
A. Before installation, clean the edges where the bearings will be placed.
Pro tip: To install new bearings, you may use a 13mm socket to properly press the bearing equally on all sides. Make sure to test if the socket fits equally around the outer bearing wall, but not get stuck in the motor well. It may take a different size socket to work. With equal pressure from the socket, the bearing should easily slip into place.
B. Apply a “SUPER THIN” coat of Loctite 480 or 680 to the outer bearing walls to secure the bearings firmly.
C. Lightly position the white ceramic bearing flat and use the 13mm socket to press equally around the outer bearing wall into the motor well. A very light finishing tap with 13mm socket and rubber mallet should seat the bearing perfectly. Wipe off excess loctite.
D. Repeat above steps with outer stainless bearing.
E. Reinstall motor mount bolts first. Use blue medium strength loctite on the bolts.
F. After letting the bearing loctite dry overnight your setup should be ready to go.
Additional note: If the bearings come out during rotor removal, reposition them after sanding and secure with Loctite 480.
The failure mode is almost always salt and moisture, not load. A few habits stretch the interval considerably.
Around one to two hours of actual work for a first attempt, plus overnight for the Loctite to cure before riding. Experienced owners do it in under an hour.
Stainless steel offers better corrosion resistance for salt water. Ceramic reduces friction and runs slightly more efficiently. The first generation TakeOff rear position accepts both, so the choice depends on whether you prioritise longevity or performance.
You can, but replacing both rear bearings together is better practice. They wear at a similar rate, and doing one means opening the motor again shortly afterwards.
The shaft has surface imperfections. Sand it with 600 CW paper, finish with 1500 CW, then test the fit again. Repeat until the bearing slides on without force. Never hammer a bearing onto a rough shaft.
Yes. A very thin coat of Loctite 480 or 680 on the outer bearing wall stops the bearing spinning in its seat, which would damage the housing. Use blue medium strength Loctite on the motor mount bolts.
For regular saltwater use with good rinsing habits, roughly once a season. Fresh water use extends this significantly. Replace them when you hear noise or feel roughness rather than on a fixed schedule.
No. The Performance motor on the TakeOff Evo is fully enclosed, so there is no bearing service interval. This guide is for the first generation TakeOff and for other brands of foil assist motor.
Every hour spent on foil assist bearing replacement is an hour not spent on the water. That is the real cost of an open motor design: not the price of two bearings, but the evening, the drying time, and the session missed while the Loctite cures.
It is why the Performance motor on the TakeOff Evo foil assist system is fully enclosed. There is no bearing service interval and no seasonal strip down. After a saltwater session it takes a ten second fresh water rinse, and the unit goes back in the bag.
If you are servicing a first generation unit or another brand today, this guide should get you through it cleanly. The steps here work, and there is real satisfaction in doing your own maintenance. But the direction the category is moving is toward motors that simply do not ask for it.
Manta Foils is not affiliated with Foil Drive or Duotone. Brand names are used for identification purposes only, to indicate the systems this maintenance guide applies to.