How to Install HubSink Hub Motor Heat Sinks
Remember the HubSinks work much more effectively with Ferrofluid, so ensure yours is still wet and effective, or install a new batch. HubSink fits QS205, MXUS, Leaf and generic hub motors. The QS273 requires the correct version to be ordered. We're super excited to hear your feedback on the installation and performance of the sinks once you've tested them out. Send us pics on Facebook or through our contact page.
Jump to: Standard motors | QS273 beta | Installation FAQ
Not sure which HubSink you need? See the HubSink V2 for hub motors, the Statorade ferrofluid, and our guides on why hub motors overheat and running more power. Every HubSink is covered by the HubSink performance guarantee.
How to install HubSinks on standard size hub motors
Be sure to have two 8mm wrenches/spanners ready to go when you start the installation.
Step 1: Clean the magnet ring
Clean the outer magnet ring surface of all dirt and oils before applying the thermal paste, don't use any petroleum based cleaners (WD-40, and many automotive degreasers). The oil, which is engineered to not evaporate, will fill the microscopic valleys in the metal and significantly reduce the effectiveness of any subsequently applied thermal compound. Keep the surface free of foreign materials and do NOT touch the surface after it has been cleaned. Oil and grease and contaminants can affect the thermal interface's performance. Oils from your fingers can adversely affect the performance by preventing the micronized silver or ceramic fill from directly contacting the metal surfaces. (Fingerprints can be as thick as 0.005”)
Step 2: Test fit the HubSinks
Test fit the HubSinks around the hub with the included mounting nuts and bolts. There will be a small (0.5mm) gap in the middle of the HubSink arch (if you have a QS273, please see the QS273 section below). When you tighten them down after riding (Step 4) this arch will pull flat and spring load against the hub, creating a solid thermal connection. Note: there will also be a gap between the end of each segment (up to 8mm at first). This is designed to keep the HubSinks pulled tight at all times during thermal expansion and contraction.
Step 3: Apply the thermal paste and fit the pieces
Apply the thermal paste/grease to the HubSink piece. This does NOT go inside the motor. (We want to use the entire 5G tube evenly across the pieces.) Insert the coated piece between the spokes and push down firmly, then give the piece a slight twist to ensure the thermal paste has coated the entire connection. Continue around the hub in the same manner, leaving the fixings slightly loose to an equal amount. Then go around the hub a few times, taking out half the space of each gap per revolution, until the pieces are all tightened down evenly. They do not need to touch end to end, a gap between pieces is acceptable (see above).
Step 4 (important): Ride hard and re-tighten
Turn the amps up and go for a ride. Try to get the hub as hot as possible on the first few rides to get the thermal paste to seat correctly and efficiently. Re-tighten the hub and ensure it is all fitted well. Repeat this for a few rides and performance will increase as the paste fills all the gaps and the alloy pulls tight against the hub.
Step 5: Enjoy
Let us know how it goes, any issues etc.
QS273 HubSink installation notes (beta testers)
The HubSinks for the QS273 are in experimental stages but are working well on some very high powered builds. Due to the larger size of the motor and sizing differences even between motors with the same branding, the pieces will have a gap in the centre of the arch which you will need to push out.
Lay one piece against your motor and roughly check the arch distance from the motor to centre. Remove the piece and bend it gently; a rubber mallet works well to push the centre of the arch down to remove most of the gap. Once you are happy with the arch fit against the motor, match the remaining ones to your master. Then follow the instructions above from Step 1, making sure the thermal paste covers the whole surface. As you tighten them down and they heat cycle, they will pull tight and fit against the motor.
Remember the HubSinks work more effectively with Ferrofluid/Statorade (a separate product which goes inside the motor and helps thermally bridge the stator to the shell), so ensure yours is still wet and effective, or install a fresh amount of Statorade if required.
Sketch Coleman
Need to know more about the paste? Thermal paste comes with every HubSink and is also sold separately. Read what thermal paste to use on a hub motor heat sink.
Hub motor heat sink installation FAQ
Why is there a gap in the middle of the HubSink arch?
There will be a small (0.5mm) gap in the middle of the arch when you first test fit. When you tighten the pieces down after riding (Step 4) the arch pulls flat and spring loads against the hub, creating a solid thermal connection.
Is a gap between the HubSink pieces okay?
Yes. There will be a gap between the end of each segment (up to 8mm at first). This is designed to keep the HubSinks pulled tight at all times during thermal expansion and contraction. The pieces do not need to touch end to end.
Does the thermal paste go inside the motor?
No. The thermal paste goes on the HubSink piece, not inside the motor.
What should I clean the magnet ring with?
Do not use petroleum based cleaners such as WD-40 or many automotive degreasers. The oil is engineered not to evaporate and fills the microscopic valleys in the metal, which significantly reduces the effectiveness of the thermal compound.
Do HubSinks need Statorade ferrofluid?
HubSinks work much more effectively with ferrofluid (Statorade), a separate product which goes inside the motor and helps thermally bridge the stator to the shell. Make sure yours is still wet and effective, or install a fresh amount.
Which motors does this installation guide cover?
It fits QS205, MXUS, Leaf and generic hub motors. The QS273 requires the correct version to be ordered, and QS273 installation notes are below.