Summary of MC 250
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Page 2: Afaico
- - . '" afaico mc250 mc400 mc440 mc501 - .•.. - .•.. .•.. Instruction book service manual from january 1974.
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Contents i. Preface page 3 ii. Technical data page 3 iii. Description of the machines page 7 a - motor b - chassis iv. Service instructions page 12 a - preparation for competition use b - assembly and repair instructions for engine - c - assembly and repair instructions for chassis index of illustra...
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- i. Preface the maico models mc 250, 400, 450 and 501 ccm are constructed and designed especially for compe- tition and off-road use. They are suitable for moto-cross and enduro competition, and for crossing any difficult terrain. The moto-cross models are known for their high horse-power output, s...
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- - spark plug: type: in moist or cold conditions: timing advance: points gap at top dead center: primary drive: primary drive ratio: clutch: transmission: champion champion champion n2 or n2g n2 or n2g n2 or n2g n3 or n3g n3 or n3g n3 or n3g 2.8 to 3.2 mm 3.5 to 3.7 mm 35mm btdc btdc btdc 03mm 0.3m...
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- - - - - - - - - •• •• ... "'-- " " ,,--- 35---- " " •• 53 15 ~ :: . \ ~\ .'d 20 '" '" " •• " ••.
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Iii. Description of the machines the maico mc 250, 400, 440 and 501 ccm motorcycles are very high performance competition motor- cycles which are designed for off-road use in difficult terrain or on a moto-cross race track. A. Motor 1. Cylinder the cyl inder is a special moto-cross cyl inder con- st...
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- - - - - -. - - 5. Primary drive the primary drive from the crankshaft to the clutch is by means of a double-row chain 3/8" x 7/32" in the mc 250 and a triple-row chain 3/8" x 7/32" in the 400, 440 and 501. The chain is an endless type and has 54 links. The manufac- ture is renold. Other brand chai...
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.- 8. Gearbox the gearbox is a dog shifting type 4 speed with 2 shift forks and a shifting cam. It is available in two different ratios, the wide ratio, which is used mainly for enduro type competition and the close ratio, which is used for moto-cross competition. On the output drive shaft is the pr...
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- - - - b. Chassis 1. Frame the double-down tube frame is made of high quality chrome moly tubing. The welds are par- tially welded with the heli-arc principle and par- tially welded with acetylene and oxygen. Espe- cially on areas subjected to high stress often found in moto-cross competition. 2. T...
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8. Fenders the front fender is rubber-mounted on the lower triple clamp. The rear fender is also rubber-mounted under the seat and on the rear frame member. Both fenders are made from vibration resistant fiberglass. - - 9. Front wheel the rim is available in either chromed steel or aluminium alloy. ...
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15. Setting ignition timing with dial indicator - - iv. Service instructions a. Preparation for competition use 1. Timing tools needed for setting the timing are a dial indicator, feeler gauge, and a buzz box or circuit breaker light. The dial indicator is either screwed into the vertical spark plug...
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Petcocks in the two petcocks are screens to prevent dirt from entering the float bowl. These screens must be cleaned regularly. Caution - only large volume petcocks can be used for adequate fuel flow. 3. Air filter before each race the air filter should be checked and cleaned. A paper filter should ...
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Next, the air release valves, located in the top oil filler caps, should be checked by compressing forks and observing air pressure release. The fork should return to its original position. If this is not the case, one must countersink the seating of the ball (for the air release valve) lightly, (ap...
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3. The retainer nut and eye are replaced and re-tightened. The shock rod is pushed all the way to the bottom and rotated clockwise until it engages and drops into the shock adjustment slots. When the rod is rotated to the extreme counter-clockwise position, the shock is on the lightest setting. 4. T...
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B. Assembly and repair instructions for engine 1. Removal from frame 1.1 remove the tank 1.2 remove the exhaust 1.3 remove the carburetor 1.4 remove the cylinder head and top engine brace 1.5 remove the ignition wire 1.6 remove the 10 mm x 1 engine mount bolts front and rear 1.7 disconnect the chain...
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With a screw driver. The puller is then remo- ved and the clutch plates and springs are lif. Ted out. On the small clutch the clutch nut retainer is also lifted out. The clutch body is held stationary with a special tool (avai- lable through the dealer i while the nut is loosened and removed. The cl...
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3.5 the final drive gear, spacer ring and three needle bearings, main shaft with sliders, lay shaft with sliders, and shift forks are re-fitted. The shift fork shaft can then be re-iocated. 3.6 a new greased center casegasket is fitted on the caseand the left case half is re-fitted with the eight 6 ...
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C. Assembly and repair instructions for chassis 1. Disassembly of forks 1.1 remove front wheel 1.2 remove handlebars and bar clamps 1.3 loosen both top 10 mm pinch bolts and remove both fork caps. 1.4 loosen both bottom pinch bolts and pull both fork tubes out of triple clamps. 1.5 drain fork oil 1....