I am asked a lot "why should I pay for BMC motor when MAC Shanghai motor costs much less?". So I decided to take two motors apart and compare.
Short history (according to Chandu at BMC). BMC and MAC used to be one company at some point, and produced motors branded MAC-BMC. Then they split off; MAC continued to produce very original V1 geared hub motor without making much changes to it, and BMC has made several improvements (outlined below) and evolved original V1 design to V2 and V3.
Here are my observations:
- * Composite gears on BMC motor are significantly stronger, capable of handling 1000+ Watts. MAC's nylon gear are rated 500 Watts max - #4. MAC's 1000W motor is not any stronger than their 500W, same clutch, same nylon gears, the only difference is that it's wound for higher RPM.
- * BMC has axle seals that prevent dust and moisture from getting inside, I've tested BMC motors in heaviest rains and never had an issue. MAC motors do not have seals - #7 & #9
- * BMC hub is potentially sturdier because it is one solid piece where MAC consists or two pieces - #6 & #7
- * Lastly, my dealings with both BMC and MAC proved outstanding customer service, for US customers BMC is easier to deal with for warranty replacements since they're based in US, Los Angeles (manufactured in India), and MAC is based in China. I heard some complaints about BMC not being very helpful in arranging replacements but that's because warranty replacements must be handled by dealers, BMC has been nice enough to deal with individuals but they don't really have much capacity for that, if a dealer tells customer to deal with BMC directly for warranty related issues, they're not doing their job.
To conclude, in my opinion 2-3 times price difference between two motors is justified, you get what you pay for. MAC motor allows to get a geared hub for a price of direct hub, and it will work fine for recreational riding at lower power levels and can be upgraded with either BMC composite gears, or one metal gear (1 is enough, 3 metal gears will be way too noisy) to handle same power levels ans BMC hubs. I don't have any data on quality of MAC's clutch/one way bearing, but it looks exactly like new once piece BMC V3 clutch, much stronger than pre 2010 BMC 2-piece clutch (pics/details: http://ebikessf.com/V2-vs-V3-clutch. For all weather commuter, I would certainly go for BMC motor because it is water resistant due to axle seals.