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New In! – The hottest bikes of 2020

Serious Bear Rock grey matt

ID: 901011
- 35%
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Product Description

Please note: all of our bike models come with an EU standard brake setup. This will need to be reversed to comply with UK cycling standards.

With the Serious Bear Rock you start powerful into the new world of E-Mountainbiking. The sporty and stable aluminium hardtail with the Bosch Performance drive offers strong support during the ascent and convinces with its real mountain bike character on all trails. The combination of a 100 mm Suntour XCT DS suspension fork and sturdy wheels lets it roll effortlessly over obstacles on the trail, offers balanced agile riding characteristics and, in combination with the powerful electric drive, ensures driving dynamics on all routes. Fully hydraulic Shimano disc brakes guarantee ample control of the bike at all speeds. Nine gears in combination with the Bosch engine integrated in the bottom bracket are enough to conquer even steep ramps. The standard large 400 Wh Li-Ion battery provides extra support and range. The Serious Bear Rock E-Mountainbike is the right partner to be more relaxed, faster or simply more often on unpaved and paved roads.

Special Features

10 years warranty


10 Year Guarantee

As a thank you to our customers, Bikester voluntarily grants an additional 10-year warranty for all VOTEC's owners, Serious, Vermont, Fixie and Ortler bikes from the date of purchase (except the VOTEC VRC which comes with a 6-year warranty on frame and fork). This warranty covers all frames from the year 2013 onwards and guarantees a replacement or repair. Follow-up costs such as assembly and transport are not included. The warranty excludes damage caused by improper use, such as: jumps, falls, overload or neglect. The guarantee expires in the case of unauthorised changes to the frame as well as the installation and conversion of additional components. In addition, a two-year warranty applies to every parts and surface.

Bosch Performance Line

On extended sports tours, on the way to work or cruising in nature - the Performance Line turns e-bikers into discoverers and adventurers. The powerful propulsion provides the required power at any time. To conclude: Riders get the perfect support in every situation to provide even more fun in the saddle - up to 25 km / h with the Drive Unit Performance Cruise or up to 45 km / h with the Speed variant.


How many miles will my battery last?  
Can I get 50 miles from one battery charge or even 120? For those interested in buying an e-bike, this is a very important question. Manufacturers try to be as realistic as they can about possible ranges your e-bike may manage on one complete battery charge. In practice, however, the maximum range depends on many different factors.  As well as the type of motor you have, factors include the energy content (400 or 500 Wh), handling and age of the battery. However, the rider's weight, sitting position, riding style (starting frequency, cadence) and selected support levels (Eco, Tour, Sport, Turbo) all greatly influence the range. Last but not least, the track profile (uphill or flat), the ground (road or terrain), wind (headwind, tailwind) and even tyre profile effect distances possible. This makes it extremely difficult to provide precise and reliable information.
25km/h E-Bike  
Intended use
E-MTB Hardtail  
Wheel Size
27.5/ 29  inches
Total number of gears
21.78  kg
Total weight
120  kg
Scope of Delivery
Includes pedals: Yes  
Damper brand: Without shock
System: MTB hardtail frame
Material type: Aluminium
Brand: Bosch
Model: Performance 
Type: Bottom bracket motor
Performance: 250 Watt
Model: Bosch Performance Line
Type: Lithium-Ion
energy storage: 400 Wh
Performance: 36 / 11,1
battery mounting: Frame battery
Bosch Purion  
Type: Bosch quick charger 2A
Voltage: 230
Range (km): 40 -90 
System: Suspension fork
Brand: Suntour
Type: XCT DS
Suspension Fork
Travel (mm): 100 mm
Shifting Components
Drivetrain type: Derailleur
Gear No.: 9
Brand: Shimano
Type: Acera
Shift Levers
Model: Shimano Altus  
Model: FSA 170 mm
Sprocket 1: 16 teeth
Model: KMC CNX9  
Sprocket Gear Ratio (teeth): 11-32 teeth
Model: Shimano Acera
Front Brakes
Brand: Tektro
Type: HDM285
Brake system: Hydraulic disc brake
Rear Brakes
Brand: Tektro
Type: HDM285
Brake system: Hydraulic disc brake
Brake Levers
Model: Shimano HDM285  
System: Riser
Model: Kalloy HB-RB11, 720 mm
Material: Aluminium
Herrmans Click  
System: A-Head
Model: Kalloy ASDC1
Material: Aluminium
System: Patent post
Diameter: 27.2 mm
Material: Aluminium
Model: Schürmann SDR light, eyeletted
Material: Aluminium
System: Hollow chamber
Niro 2.0 black  
Front Tyre
Tire width: 53 mm
Model: Impac Ridgepack
Rear Tyre
Tire width: 53 mm
Model: Impac Ridgepack
VP VPE-890  
Model year
Product number
Customer Ratings
23 Customer Ratings
5 Stars
4 Stars
3 Stars
2 Stars
1 star
Nice bike
Mooie fieta
Translated from Dutch To the original

Good quality

Goede kwaliteit

All the best, gladly again
Alles Bestens, gerne wieder
Translated from German To the original

Super price performance, great price performance and uncomplicated

Super Preis Leistung, tolle Preis-Leistung und komplikationslos

Excellent MTB
Ottima MTB
Automatically translated from Italian To the original

I used it for the rides on our hills with pretty rough roads, the bike looks good. The engine and the battery work well, gear changes without problems. The battery can be exchanged with the one installed on my husband's BULLS e-bike, this is very useful.  The courier has delivered the bike with 4 days of delay over 8 working days provided by the order, this is a weak point for those who want the bike quickly. The only flaw: only after 2 laps of 40 km did the front tire completely deflate.

L'ho usata per i giri sulle nostre colline con le strade abbastanza dissestate, la bici sembra buona. Il motore e la batteria funzionano bene, marce si cambiano senza problemi. La batteria può essere scambiata con quella istallata sulla e-bike BULLS del mio marito, questo e molto utile. Il corriere ha consegnato la bici con 4 giorni di ritardo sopra 8 giorni lavorativi previsti dal'ordine, questo e punto debole per chi vuole la bici velocemente. Unica pecca: solo dopo 2 giri di 40 km si e completamente sgonfiata la gomma anteriore.

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