Maico MC 250 Instruction Book

[Page 1] Maico MC 250

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[Page 2] Maico MC 250

- - . '" AfAICO MC250 MC400 MC440 MC501 - .•.. - .•.. .•.. Instruction book Service manual From January 1974 ...

[Page 3] Maico MC 250

CONTENTS I. Preface Page 3 II. Technical data Page 3 III. Description of the machines Page 7 A - Motor B - Chassis IV. Service instructions Page12 A - Preparation for competition use B - Assembly and repair instructions for engine - C - Assembly and ...

[Page 4] Maico MC 250

- 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 mod...

[Page 5] Maico MC 250

- - 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 ...

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- - - - - - - - - •• •• ... "'-- " " ,,--- 35---- " " •• 53 15 ~ :: . \ ~\ .'D 20 '" '" " •• " •• ...

[Page 7] Maico MC 250

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 c...

[Page 8] Maico MC 250

- - - - - -. - - 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 endles...

[Page 9] Maico MC 250

.- 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-cros...

[Page 10] Maico MC 250

- - - - 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 ...

[Page 11] Maico MC 250

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 avai...

[Page 12] Maico MC 250

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 indica...

[Page 13] Maico MC 250

Petcocks In the two petcocks are screensto prevent dirt from entering the float bowl. These screensmust be cleaned regularly. Caution - Only large volume petcocks can be used for adequate fuel flow. 3. AIR FILTER Before each race the air filter shoul...

[Page 14] Maico MC 250

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...

[Page 15] Maico MC 250

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 po...

[Page 16] Maico MC 250

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 m...

[Page 17] Maico MC 250

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 deal...

[Page 18] Maico MC 250

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 greasedcenter casegasket is fitted on the caseand ...

[Page 19] Maico MC 250

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...