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    • Mount a Non-Derailleur Rear Wheel & Tension The Chain

    Introduction

    The length of the chain can only be adjusted in increments of 1 inch(link). On a derailleur bike a spring loaded arm holds the chain in tension. If the bike has only one position for the chain the distance between the cog-wheel connected to the pedals that pulls the chain, and the cog wheel on the rear wheel that the chain pulls must be exactly right.

    Step 1

    <h3>Step 1</h3><p>Hang the drive chain on the seat stay. Put the rear rear wheel into the frame as far forward as possible. Transfer the cain onto the sprocket. </p> </div>

    Put The rear Wheel on The Bike

    Hang the drive chain on the seat stay. Put the rear rear wheel into the frame as far forward as possible. Transfer the cain onto the sprocket.

    Step 2

    <h3>Step 2</h3><p>Once the rear wheel is in the frame and the chain is running on the cog wheels set yourself behind the bike with your head on the centre line. Pull the rear wheel back with one hand watching to check that it’s centred in the frame. </p> </div>

    Get Behind The Bike

    Once the rear wheel is in the frame and the chain is running on the cog wheels set yourself behind the bike with your head on the centre line. Pull the rear wheel back with one hand watching to check that it’s centred in the frame.

    Step 3

    <h3>Step 3</h3><p>Do one nut up finger tight. Carefully so as not to disturb the rear wheel switch hands and do the other nut up with your fingers. </p> </div>

    Finger-tight

    Do one nut up finger tight. Carefully so as not to disturb the rear wheel switch hands and do the other nut up with your fingers.

    Step 4

    <h3>Step 4</h3><p>Half tighten the nuts with a spanner. It’s usually a 15mm </p> </div>

    First Position

    Half tighten the nuts with a spanner. It’s usually a 15mm

    Step 5

    <h3>Step 5</h3><p>If the bike has a fixed gear pick it up so the rear wheel comes off the ground and spin the pedals. If the bike has a freewheel you can do this by spinning the pedals backwards. The chain needs to be as tight as possible without creating friction that will waste energy and wear the chain and cogs prematurely. </p> </div>

    Test

    If the bike has a fixed gear pick it up so the rear wheel comes off the ground and spin the pedals. If the bike has a freewheel you can do this by spinning the pedals backwards. The chain needs to be as tight as possible without creating friction that will waste energy and wear the chain and cogs prematurely.

    Step 6

    <h3>Step 6</h3><p>To adjust the rear wheel’s position loosen one side and push the rim between the chain stays to one side to move the loose end of the axle a short distance back or forward. Re-tighten the nut. Loosen the other side and ease the rim in the other direction so the rear wheel is – once again – straight in the frame. </p> </div>

    Walk The rear Wheel

    To adjust the rear wheel’s position loosen one side and push the rim between the chain stays to one side to move the loose end of the axle a short distance back or forward. Re-tighten the nut. Loosen the other side and ease the rim in the other direction so the rear wheel is – once again – straight in the frame.

    Step 7

    <h3>Step 7</h3><p>Test again and repeat the process moving the rear wheel a short distance forward or back until the tension is in the target zone. You need to test by spinning pedals because neither cog-wheel will be a perfect circle so the chain tension will vary as the cranks spin. </p> </div>

    Never Release The rear Wheel Fully

    Test again and repeat the process moving the rear wheel a short distance forward or back until the tension is in the target zone. You need to test by spinning pedals because neither cog-wheel will be a perfect circle so the chain tension will vary as the cranks spin.

    Step 8

    <h3>Step 8</h3><p>Once the chain tension is acceptable tighten both nuts fully. If the bike is to be used for travel lock the nuts with the spanner you carry for puncture repairs. If you use a longer spanner in the workshop they may be hard to undo with your carry-along spanner. </p> </div>

    Fully Tighten

    Once the chain tension is acceptable tighten both nuts fully. If the bike is to be used for travel lock the nuts with the spanner you carry for puncture repairs. If you use a longer spanner in the workshop they may be hard to undo with your carry-along spanner.

    Pro Tip

    Some bikes use an eccentric bottom-bracket to adjust the position of the crank-axle to get the correct chain tension.This method is often used to adjust the timing-chain – that connects the two sets of pedals – on a tandem.