001BA174 KN
There are two mechanisms which could induce braking under the conditon that the brake is in a properly maintained condition:
–manual activation: If a kickback occurs, the chain saw moves upwards towards the user in a rotating motion around the front handle. The brake is engaged once the hand contacts the front guard, which is the activtion lever for the brake.
–inertia activation: All STIHL chain saws are equipped with an interia Quickstop chain brake. If the kickback impulse is strong enough, this alone is sufficient to engage the brake even without contacting the front hand guard.
MS 250
WARNING
Never operate your chain saw without a front hand guard. In a kickback situation this guard helps protect your left hand and other parts of your body. In addition, removal of the hand guard on a chain saw equipped with a Quickstop chain brake will disable the activation mechanism of the chain brake.
WARNING
No Quickstop or other chain brake device prevents kickback. These devices are designed to reduce the risk of kickback injury, if activated, in certain kickback situations. In order for the Quickstop to reduce the risk of kickback injury, it must be properly maintained and in good working order. See the chapter of your instruction manual entitled "Chain Brake" and the section "Maintenance, Repair and Storing" at the end of these Safety Precautions. In addition, there must be enough distance between the bar and the operator to ensure that the Quickstop has sufficient time to activate and stop the chain before potential contact with the operator.
WARNING
An improperly maintained chain brake may increase the time needed to stop the saw chain after activation, or may not activate at all.
WARNING
Never run the chain saw above idle speed for more than 3 seconds when the chain brake is engaged or when the saw
English
chain is pinched or otherwise caught in the cut. Clutch slippage can cause excessive heat, leading to severe damage of the motor housing, clutch and oiler component and may interfere with the operation of the chain brake. If clutch slippage in excess of 3 seconds has occurred, allow the motor housing to cool before proceeding and check the operation of your chain brake as described in the chapter entitled "Chain Brake" of your instruction manual. Also make sure that the saw chain is not turning at idle speed (see above at "Important Adjustments").
Low Kickback Saw Chain and Reduced Kickback Bars
STIHL offers a variety of bars and saw chains. STIHL reduced kickback bars and low kickback saw chains are designed to reduce the risk of kickback injury. Other saw chains are designed to achieve higher cutting performance or sharpening ease, but in turn are more prone to kickback.
STIHL has developed a color code system to help you identify the STIHL reduced kickback bars and low kickback saw chains. Cutting attachments with green warning decals or green labels on the packaging are designed to reduce the risk of kickback injury. The matching of green decaled chain saws under
3.8cubic inches (62 cm³) displacement with green labeled bars and green labeled saw chains gives compliance with the computed kickback angle requirements of the chain saw standard when the products are in their original condition. Products with yellow decals or labels are for users with extraordinary
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