Hostel Shoppe - Recumbent Chain Installation and Sizing

Hostel Shoppe - Your Recumbent Bicycle, Tricycle, and Tandem Headquarters

Order Hostel Shoppe's 2004 Recumbent Catalog

Hostel Shoppe's FREE Recumbent Classified Ads

Tech Tips, Recumbent Info, and Expert Advice

Store Policies, Ordering Info and all about US

Chain Length Adjustment

On recumbents with an adjustable boom, it is necessary to adjust the chain length after adjusting the boom for your leg length. A good rule of thumb for leg extension is as follows: Adjust the boom so that you can lock your knee straight when your heel is centered over the pedal spindle. When you move your foot back to the regular riding position (ball of foot over pedal spindle) your knee should have a slight bend in it. After adjusting the boom length, adjust the chain length as follows: You will need a chain tool!

First, shift the chain into the largest chainring in the front and the largest cog in the rear. This is known as a "crossover gear." You may want to avoid this gear combination, but it is important that your chain is long enough to allow for an accidental shift into this combination.

Next, break the chain and unwind the chain from the rear derailleur pulleys. With the chain on the largest sprockets, pull the two ends of the chain together. Add or remove enough chain links to achieve a ONE LINK OVERLAP(see picture at left) - note where the two ends of the chain meet and add one link to it.

Review BEFORE you cut the chain:

Route the chain over the BIGGEST front chainring.
BYPASS the rear derailleur.
Route the chain over the BIGGEST rear cassette cog.
Make sure the chain is not routed through the rear derailleur but is routed through any pulleys or idlers elsewhere on the bike.
Add one link to the chain length.

After cutting the chain to the correct length, re-route the chain through the rear derailleur. Move the chain and derailleurs to the smallest chainring in the front and the smallest cog in the rear to allow for easier reconnection. After verifying that the chain is routed through the derailleurs, idlers and pulleys correctly, reconnect the two ends of the chain.

If all is done correctly, the rear derailleur should have just enough tension to keep the chain from rubbing on the derailleur itself (see picture) when the chain is on the smallest chainring in the front, and the smallest cog in the rear. Note: If your bike has a non-standard gear combination (i.e. REALLY large big chainring and REALLY small small chainring) your derailleur may not be able to take up this slack. That is acceptable because you should not be riding in the small/small "crossover gear" either, and it is much more important to have room to shift into the big/big combination as severe damage to your frame/derailleur/wheel can occur if your chain is too short.

IMPORTANT --- WITH YOUR BIKE ON A BIKE STAND, TEST FOR ENOUGH CHAIN LENGTH AS FOLLOWS:
With the chain on the smallest rear sprocket, shift the chain onto the largest front chainring. SLOWLY shift the rear gears until you reach the largest cog (or find out you can't). If the last gear (or two) are difficult, or it appears that the derailleur is stretched too far, DO NOT FORCE IT! - your chain is too short and you will need to add a link or two! Proper derailleur extension is shown at left (big/big gear combo).

Back to Tech Tips

Chain Length Adjustment On recumbents with an adjustable boom, it is necessary to adjust the chain length after adjusting the boom for your leg length. A good rule of thumb for leg extension is as follows: Adjust the boom so that you can lock your knee straight when your heel is centered over the pedal spindle. When you move your foot back to the regular riding position (ball of foot over pedal spindle) your knee should have a slight bend in it. After adjusting the boom length, adjust the chain length as follows: You will need a chain tool!
	First, shift the chain into the largest chainring in the front and the largest cog in the rear. This is known as a "crossover gear." You may want to avoid this gear combination, but it is important that your chain is long enough to allow for an accidental shift into this combination.
	Next, break the chain and unwind the chain from the rear derailleur pulleys. With the chain on the largest sprockets, pull the two ends of the chain together. Add or remove enough chain links to achieve a ONE LINK OVERLAP(see picture at left) - note where the two ends of the chain meet and add one link to it. Review BEFORE you cut the chain: Route the chain over the BIGGEST front chainring. BYPASS the rear derailleur. Route the chain over the BIGGEST rear cassette cog. Make sure the chain is not routed through the rear derailleur but is routed through any pulleys or idlers elsewhere on the bike. Add one link to the chain length.
	After cutting the chain to the correct length, re-route the chain through the rear derailleur. Move the chain and derailleurs to the smallest chainring in the front and the smallest cog in the rear to allow for easier reconnection. After verifying that the chain is routed through the derailleurs, idlers and pulleys correctly, reconnect the two ends of the chain.
	If all is done correctly, the rear derailleur should have just enough tension to keep the chain from rubbing on the derailleur itself (see picture) when the chain is on the smallest chainring in the front, and the smallest cog in the rear. Note: If your bike has a non-standard gear combination (i.e. REALLY large big chainring and REALLY small small chainring) your derailleur may not be able to take up this slack. That is acceptable because you should not be riding in the small/small "crossover gear" either, and it is much more important to have room to shift into the big/big combination as severe damage to your frame/derailleur/wheel can occur if your chain is too short.
	IMPORTANT --- WITH YOUR BIKE ON A BIKE STAND, TEST FOR ENOUGH CHAIN LENGTH AS FOLLOWS: With the chain on the smallest rear sprocket, shift the chain onto the largest front chainring. SLOWLY shift the rear gears until you reach the largest cog (or find out you can't). If the last gear (or two) are difficult, or it appears that the derailleur is stretched too far, DO NOT FORCE IT! - your chain is too short and you will need to add a link or two! Proper derailleur extension is shown at left (big/big gear combo).