Did you just stumble upon a download or a file on your computer that is digitally signed by Mountain Bike? Some of the security products refers to the detected files as Adware.SwiftBrowse.CH and W64/A-59c9c70a!Eldorado. The detection rate for the Mountain Bike files collected here is 45%. Please read on for more details.
You will typically see Mountain Bike when running the file. The publisher name is displayed as the "Verified publisher" in the UAC dialog as the screenshot shows:

You can view additional details from the Mountain Bike certificate with the following procedure:
Here's a screengrab of a file that has been signed by Mountain Bike:

As you can see in the screenshot above, Windows states that "This digital signature is OK". This implies that the file has been published by Mountain Bike and that the file has not been tampered with.
If you click the View Certificate button shown in the screengrab above, you can view all the details of the certificate, such as when it was issued, who issued the certificate, how long it is valid, and so on. You can also examine the address for Mountain Bike, such as the street name, city and country.
VeriSign Class 3 Code Signing 2010 CA has issued the Mountain Bike certificates. You can also examine the details of the issuer by clicking the View Certificate button shown in the screengrab above.
These are the Mountain Bike files I have gathered, thanks to the FreeFixer users.
Here's the detection names for the Mountain Bike files. I have grouped the detection names by each scanner engine. Thanks to VirusTotal for the scan results.
| Scanner | Detection Names |
|---|---|
| ALYac | Adware.SwiftBrowse.CH |
| AVG | Generic.11A, AdPlugin.DAI |
| AVware | Trojan.Win32.Generic!BT |
| Ad-Aware | Adware.SwiftBrowse.CH |
| Agnitum | Riskware.Agent! |
| Antiy-AVL | GrayWare[NetTool:not-a-virus]/Win64.NetFilter.a |
| Baidu-International | Adware.Win32.BrowseFox.Moun |
| BitDefender | Adware.SwiftBrowse.CH |
| Bkav | W64.HfsAdware.680C, W64.HfsAdware.7E9D |
| ClamAV | Win.Adware.Swiftbrowse-497 |
| Cyren | W64/A-59c9c70a!Eldorado |
| DrWeb | Tool.NetFilter.313, Trojan.Yontoo.1742, Trojan.Yontoo.1735 |
| ESET-NOD32 | a variant of Win64/NetFilter.A potentially unsafe |
| Emsisoft | Adware.SwiftBrowse.CH (B) |
| F-Prot | W64/A-59c9c70a!Eldorado |
| F-Secure | Adware.SwiftBrowse.CH |
| Fortinet | Adware/NetFilter |
| GData | Adware.SwiftBrowse.CH |
| Jiangmin | AdWare/Yotoon.ra |
| K7AntiVirus | Adware ( 0040f9f21 ) |
| K7GW | Adware ( 0040f9f21 ) |
| McAfee | Artemis!387E2D380479, Artemis!E02BB0B8AA7D, Artemis!4EB28AD9D54F, Artemis!B0959C127FC6, Artemis!DA8F19ABD3DE |
| McAfee-GW-Edition | BehavesLike.Win64.Suspicious.ph, BehavesLike.Win64.PUPAmonetize.ph |
| MicroWorld-eScan | Adware.SwiftBrowse.CH |
| NANO-Antivirus | Riskware.Win64.NetFilter.dpehxh, Trojan.Win64.Yontoo.dqjwxl, Trojan.Win64.Yontoo.dqfqnk |
| Symantec | Trojan.Gen.2 |
| Tencent | Win64.Adware.Bp-sys.Zuxl |
| TrendMicro | HS_BROWSEFOX.SM, TROJ_GEN.R02KC0OCG15 |
| TrendMicro-HouseCall | HS_BROWSEFOX.SM, TROJ_GEN.R02KC0OCG15 |
| VIPRE | Trojan.Win32.Generic!BT |
| Zillya | Adware.Yotoon.Win64.14 |
| nProtect | Adware.SwiftBrowse.CH |
The detection percentage is based on that I've collected 838 scan results for the Mountain Bike files. 373 of these scan results came up with some sort of detection. You can review the full details of the scan results by examining the files listed above.
The analysis has been done on certificates with the following serial numbers: