Honda CRF là một dòng xe địa hình 4-thì được sản xuất bởi Honda.
Dòng CRF được ra đời năm 2000 kế nhiệm dòng Honda XR. The full sized motocross bikes are equipped with liquid-cooled, single cylinder four-stroke engines that are available from 149 cc (9.1 cu in) to 449 cc (27.4 cu in). They now have dual-sport motorcycles. The more trail friendly CRF’s have simple air-cooled engines, and are available from 50 cc (3.1 cu in) to 230 cc (14 cu in). Honda CRF450R là chiếc đầu tiên của dòng xe này, followed by the CRF250R in 2004. Further down the line, the CRF450X and CRF250X bikes emerged, both designed for mostly off-road use. They are considered among the best motorcross bikes of their class, and have been a leading seller since their introduction. The CRF450R was CycleWorld’s Best Motocrosser for a record eight consecutive years from 2002-2009.
Công nghệ động cơ
The engines in these bikes use an over-square design, which means that the diameter of the cylinder is larger than the stroke of the piston. This allows for higher engine speeds and a reduction of reciprocating mass for a given displacement. Another technology that is used is short piston skirts. The “skirt” area of the piston is the portion on the side of the piston which comes into contact with the cylinder wall and aids piston stability. While the introduction of the shorter skirt on the piston helps to reduce reciprocating mass, it also leads to more “rocking” of the piston, or minute unwanted rotation of the piston around the axis of its wrist pin. This leads to more frequent maintenance intervals for the pistons, piston rings, and cylinder walls.
Các mẫu xe
Đến năm 2019, the CRF-F gồm có CRF50F, CRF70F, CRF110F, CRF125F, CRF125F (Big Wheel),CRF230F, và CRF250F. For the 2019 Model year the CRF 110F, CRF125F, and CRF250F all come standard with Electronic Fuel Injection. This improves cold weather starting and makes the bike easier to maintain because of the lack of a carburetor to clean.
Simple, air-cooled 4-stroke motorcycles. Typically, these bikes come in low-power and confidence inspiring configurations for new market entrants. In all, Honda has made a CRF50F, CRF70F, CRF80F, CRF100F, CRF110F, CRF125F, CRF125FB, CRF150F, CRF230F, and a CRF250F.
The CRF70F, CRF80F, CRF100F, and CRF150F không còn được sản xuất. Chiếc 70cc được thay thế bằng 110cc, 80cc và 100cc được thay thế bằng 125cc, và 150F không có bản thay thế nào.
As of 2017, the CRF-R series includes the CRF150R, CRF250R, and CRF450R.
These liquid-cooled four-stroke machines were designed to be utilized purely for closed-course motorcross racing. The CRF-R lineup lacks any extra accessories; like lights and electric start (Although offered as an option on the 2017 CRF-450R).
CRF-450R Notable Changes
|2004||Ghi đông 22mm (7/8″)|
|2008||Honda Progressive Steering Damper|
|2009||Phun xăng điện tử|
|2013||Giảm xóc hơi, 2 ống xả|
|2017||Giảm xóc dầu, tùy chọn khộng bằng đề|
As of 2018, the CRF-RX series includes the CRF250RX and CRF450RX.
This machine was built as a CRF-450R that was optimized for hare scramble, hard enduro, GNCC style racing. Essentially the same as the CRF-450R except offered as standard equipment an electric start, larger fuel tank, and an 18-inch rear wheel. This bike is to bridge the gap between the more mild X-model and the closed-course race style R model. (First model year: 2017)
As of 2014, the CRF-X series includes the CRF250X and the CRF450X.
These bikes have electric start, but are still considered race bikes, albeit for off-road rather than motocross. Differences from the R models include lighting, electric start, suspension settings, engine and exhaust tuning for more low-end torque, larger fuel tanks, and a more rugged widespread ratio transmission. Robby Bell won the San Felipe 250 in 2006, 2007 and 2008.
In 2008, the CRF230L was introduced as an entry-level dual-purpose motorcycle. It was discontinued, several years later, with the introduction of a completely redesigned dual-purpose motorcycle. Being a dual-sport motorbike, these bikes are street legal from the factory, but still have a dirt-oriented design. They have a completely different frame and engine from Honda’s other CRF formats, and most other components are not shared with the other CRF(non-street-legal) motorcycles. These different components meet emissions and government road regulations. All have full lighting and electric starts. Outside of the United States, the CRF230L was marketed as the XR230L.
Vào tháng 4/2012, the completely redesigned dual-purpose CRF250L ra mắt tại Nhật Bản. It shares a liquid-cooled 249 cc 4-stroke DOHC single-cylinder EFI engine with the CBR250R. Được sản xuất ở Thái Lan.
Vào tháng 11 năm 2017, một mẫu mới có tên CRF150L được ra mắt tại Indonesia. Động cơ EFI 149cc 4-stroke SOHC xi lanh đơn làm mát bằng gió được dùng trên Verza. Nó được sản xuất bởi Astra Honda Motor.
In April 2013, exactly one year after the initial launch of the CRF250L, Honda thông báo kế hoạch bán một phiên bản supermoto của chiếc dual-purpose ở châu Âu. CRF250M được dựa trên chiếc xe dual-purpose CRF250L, with revised suspension, uprated front brake và vành 17-inch với lốp bản rộng. CRF250M adds another A2 licence-friendly machine to Honda’s line-up.