Owner's Manual

15
Connecting chain tension on a Rohloff equipped tandem
The tension of the chain which transfers drive from the front to the rear of your tandem (connecting
chain) is adjusted by way of an eccentric insert on the front bottom bracket.
1) There is always a “tight spot” on all chain drive systems; when setting chain tension there
must always be some slack in the chain at this “tight spot”. A slack chain will do no damage
whatsoever, if it is allowed to become very slack the only danger is that it may fall off. By
contrast, a chain which is too tight wears prematurely causes premature wear to the bottom
bracket assembly and causes unnecessary expenditure of energy in use.
2) Once the bottom bracket screws have been tightened, do not re-adjust the chain tension
until T1 - T2 reaches 40mm (T1-T2=40mm). The “crude but simple, reliable and effective”
system we use for locking the eccentric depends upon the points of the screws being able to
bite into the alloy eccentric… if unnecessary chain adjustments are made, the holes created
by the points will be too close together and the eccentric will simply slip back into its
previous position.
3) The chain should be adjusted before T1 – T2 reaches 60mm (T1-T2=60mm). Failure to do
this makes it possible for the chain to become slack enough to fall off the chain ring.
4) With a new chain (and especially a whole new transmission), it may not take very long for
40mm of slack to become 60mm of slack but please don’t worry…this situation will improve
dramatically with the passing of the miles.
To re-adjust the connecting chain tension on tandem cycles
NB. When adjusting the chain tension on a tandem you may have to slacken the connecting chain
tension using the front eccentric before you start. You will have to subsequently need to readjust
the connecting chain tension in any case. Follow the instructions on pages 13 and 14 for how to
correctly position the eccentrics when tensioning the transmission chain.