SECTION J: LUBRICATION.
When lubricating your Brompton, avoid getting oil or grease on the seat pillar or the wheel rims.
Grease is the right lubricant for all wearing parts (oil does not last as well), and where it is
practical to dismantle an assembly and apply grease, it's best to do so. However, this is often
inconvenient or impossible, and oil can be used instead, but note that applying oil to a greased
assembly can cause the remaining grease to be washed away fairly quickly, and frequent
re-lubrication is needed thereafter (unless you re-grease).
Choice of lubricant: any good quality general purpose grease is satisfactory, especially lithium
based. For the chain, proprietary chain lubricants with good penetrating properties give the best
results. As for oil, some spray-on products are convenient to use, otherwise employ an ordinary
light mineral oil. For the rear hub, Sram recommends:
a) for the bearings and gears, Sram grease "Fett type A": Brompton can advise where to
obtain this.
b) for the pawls, light mineral oil.
The chart on p.25 shows what to lubricate. For medium frequency items (marked "3"), a sensible
guide for the interval between lubrication is a year, or 5,000 miles.
Notes:
a) Chain: for smooth pedalling the chain HAS to be well lubricated: if the bike is used in the wet,
this should be done frequently. The easiest way to cover the whole chain is to turn the pedals
backwards while applying oil: make sure that the oil flows both onto the rollers and between the
side plates: turn the pedals a few more times to allow the oil to work in, and then wipe off excess
oil.
b) Hinge clamps: a thin smear of grease on the inside faces of the clamp plates ensure that
these release OK: the thread of the clamp bolt, and its washer, should also be greased.
c) Folding pedal: the pivot spindle on which it folds likes greasing from time to time. The main
bearing, which is grease packed, should not be oiled: however, if the bearing is not running freely,
some oil fed in past the seal will extend its useful life.
d) Rear hinge: this comprises a stainless steel shaft running in pre-greased bushes and these
will normally give a very long maintenance free life; however, after the first say 10,000 miles or 2
years, an occasional application of oil is recommended.
e) Hub gears: the gears and bearings are sealed; greasing need only be carried out during major
service.