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7. CYLINDER/PISTON

7-0

Bet & Win 2 50

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CYLINDER/PISTON

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SCHEMATIC DRAWING ---------------------------------------------- 7-1

SERVICE INFORMATION -------------------------------------------- 7-2

TROUBLESHOOTING ------------------------------------------------- 7-2

CYLINDER REMOVAL------------------------------------------------ 7-3

PISTON REMOVAL ---------------------------------------------------- 7-3

PISTON INSTALLATION --------------------------------------------- 7-7

CYLINDER INSTALLATION----------------------------------------- 7-7

Summary of content (9 pages)

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7. CYLINDER/PISTON Bet & Win 250 SERVICE INFORMATION GENERAL INSTRUCTIONS • The cylinder and piston can be serviced with the engine installed in the frame. • When installing the cylinder, use a new cylinder gasket and make sure that the dowel pins are correctly installed. • After disassembly, clean the removed parts and dry them with compressed air before inspection. SPECIFICATIONS Item Cylinder Piston, piston ring I.D.
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7. CYLINDER/PISTON Bet & Win 250 Cylinder Cam Chain Guide CYLINDER REMOVAL Remove the cylinder head. (!6-7) Remove the water hose from the cylinder. Water Hose Remove the cam chain guide. Remove the cylinder. Remove the cylinder gasket and dowel pins. Clean any gasket material from the cylinder surface. Gasket Dowel Pins PISTON REMOVAL Shop Towel Piston Rings Remove the piston pin clip. Press the piston pin out of the piston.
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7. CYLINDER/PISTON Bet & Win 250 Inspect the piston, piston pin and piston rings. Remove the piston rings. ＊ • Take care not to damage or break the piston rings during removal. Clean carbon deposits from the piston ring grooves. Install the piston rings onto the piston and measure the piston ring-to-groove clearance. Service Limits: Top: 0.09mm replace if over 2nd: 0.09mm replace if over Remove the piston rings and insert each piston ring into the cylinder bottom.
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7. CYLINDER/PISTON Bet & Win 250 Measure the piston pin O.D. Service Limit: 16.96mm replace if below Measure the piston O.D. ＊ • Take measurement at 9mm from the bottom and 90° to the piston pin hole. Service Limit: 72.60mm replace if below Measure the piston-to-piston pin clearance. Service Limit: 0.02mm replace if over CYLINDER INSPECTION Inspect the cylinder bore for wear or damage. Measure the cylinder I.D.
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. CYLINDER/PISTON Bet & Win 250 Inspect the top of the cylinder for warpage. Service Limit: 0.05mm repair or replace if over Measure the connecting rod small end I.D. Service Limit: 17.06mm replace if over PISTON RING INSTALLATION Install the piston rings onto the piston. Apply engine oil to each piston ring. ＊• Be careful not to damage the piston and piston rings during assembly. • All rings should be installed with the markings facing up.
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7. CYLINDER/PISTON Bet & Win 250 PISTON INSTALLATION Remove any gasket material from the crankcase surface. ＊ • Be careful not to drop foreign matters into the crankcase. Piston Install the piston, piston pin and a new piston pin clip. ＊• Position the piston “IN” mark on the intake valve side. • Place a clean shop towel in the crankcase to keep the piston pin clip from falling into the crankcase.
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7. CYLINDER/PISTON Bet & Win 250 Install the cam chain guide. ＊ • Insert the tab on the cam chain guide into the cylinder groove. Dowel Pin Install the cylinder gasket and dowel pins. Connect the water hose to the cylinder. Install the cylinder head. (!6-9) Tighten the cylinder base bolt.