I have seen a Far Eastern (Vietnam) seller advertising 'fake' and 'real'
See here: https://dngbike.com/search?query=fake ( though some of those above have been deleted )
Fake RD-M4000 here on YT
Also my experience in Indonesia is that the market is completely flooded with fake RD-M390. The local selling price is around US$3.50
IME the selling prices of genuine Shimano varies regionally, somethings are cheaper in some territories.
There are some reviews on that listing suggesting that they are fake.
Product fake. Poor quality. Spoke with the seller to cancel the purchase before shipment but he ignored and only answer after shipping. AND the worst: The Loop 9 speeds not works, is locked. Trying a dispute but the seller not respond and the AliExpress ruled complaint unfounded. Worst purchase that ever made on AliExpress. Not Buy: fake, fake, fake.
In order to verify whether a product is real it can be hard to tell without a comparator in hand, so you'd have to order and then find a new, real Shimano product from a trusted source (i.e. not ebay, third-party Amazon sellers, etc.)
I'm not sure if M4000 is made in any respect in China. I have seen various sources: Japan, Malaysia, Indonesia.
Selling prices for known-genuine RDs in Indonesia (same seller, 100% genuine):
- TZ50/TZ500/TZ31 $4.50
- TX35 $5.50
- TY300 $6.50
- TX800 $9.75
- M310 $12.50
- M2000 $16.00
- R2000 $17.50
- R3000 $21.00
- M3000 $22.00
- 4700 $24.50
- M4000 $28.00
- M6000 $42.00
- R8000 $65.00
- M8000 $85.00
- R9100 $166.00
- Di2 M8050 $226.00
These are full retail prices and published discounts do not exist, but you might get 10% off if you bought from a retailer in person.
The fake Shimano are openly sold in Indonesia apparently with the euphemism 'OEM'. E.g. https://www.bukalapak.com/products?utf8=%E2%9C%93&source=navbar&from=omnisearch&search_source=omnisearch_organic&from_keyword_history=false&search%5Bkeywords%5D=shimano+oem
Besides the items I list from above, some 'OEM' (fake) items listed are:
Some Indonesian retail prices for genuine shifters (per ONE shifter):
- EF41 $5.50
- M370 $9.00
- M2000 $10.50
- M3000 $14.00
- M4000 $21.00
- M6000 $23.00
- M8000 $35.00
- R3000 STIs $55.00
- 4700 STIs $62.00
FD-M4000 runs around $12.50
So in answer to your question for the AliX listing:
- shifters - fake, garbage, missing logo. Indonesian price for fake pair ~$6, this at $15 is a rip-off.
- rear derailleur - fake for sure, just look at the image, no logo, laughable garbage. Indonesian price for fake RD ~$10
- front derailleur - quite possibly genuine?
So 100% definitely for sure fake. How do you tell? You can't - there is fake Shimano, fake KMC, and more on AliExpress. I am not sure if they haved faked hydraulic disc brakes - but I wouldn't guarantee it.
I would add that given that a lot of this stuff is made in Malaysia/Indonesia/Japan, a Chinese seller is a BAD place to buy it, because they've either faked it or imported it. Maybe DYOR on which Shimano is made in China?