2022 Ronstan Marine Catalogue - Flipbook - Page 42
SPORTS BLOCKS
40
Series 75 Two-Speed Mainsheet Systems
RF70300
RF72700T
3:1
or
6:1
4:1
or
8:1
RF72700B
RF72900B
6:1
RF72330
Two-speed mainsheet systems allow fine tuning of
the mainsheet when sailing upwind by using one
of the sheet tails and keeping the other cleated.
Using both the sheets at once allows the trimmer
to blow off the main quickly when rounding the top
mark and trim on quickly when hardening up after
rounding the bottom mark.
When fitting to traveller cars, ensure adequate
support for the bottom block and use stand-up
spring kit RF324-1 or RF324-2. (Refer to traveller
section pages 100 & 105 for more information).
PRODUCT No.
RF72900T
DESCRIPTION
Ball Bearing
RF70300
BB triple block, universal head
RF72330
Ratchet triple block, becket, cleat, universal head
RF72700
Complete system, BB & ratchet 3:1 coarse, 6:1 fine
RF72700B
Ratchet bottom block for RF72700 two-speed system
RF72700T
BB top blocks for RF72700 two-speed system
RF72900
Complete system, BB & ratchet 4:1 coarse, 8:1 fine
RF72900B
Ratchet bottom block for RF72900 two-speed system
RF72900T
BB top block for RF72900 two-speed system
RF72700
RF72900
3:1
or
6:1
4:1
or
8:1
Rope not
included
Two-speed systems: Mainsheets on
sportsboats and keelboats to 12m (40ft).
Ball bearings: acetal.
MAXIMUM MAINSAIL AREA
Cheeks & ratchet sheaves: Anodised aluminium.
Sheaves: UV stabilised acetal (BB), alloy (ratchet).
RF72700: End boom = 38m2 (409ft2),
Mid-boom = 23m2 (248ft2)
Ratchet pawl: Torlon®.
RF72900: End boom = 42m2 (452ft2),
Mid-boom = 27m2 (290ft2)
SHEAVE
DIAM.
mm
MAX.
ROPE
mm
PIN
DIAM.
mm
M.W.L.
kg
B.L.
kg
WEIGHT
g
SHEAVE
DIAM.
in.
MAX.
ROPE
in.
PIN
DIAM.
in.
M.W.L.
lb
B.L.
lb
WEIGHT
oz
75
75
75 + 50
75 + 50
75 + 50
75 + 50
75 + 50
75 + 50
10
10
10
10
10
10
10
10
7
7
7
7
7
7
7
7
1250
685
800
800
800
1100
1100
1100
2500
2000
1700
1700
1700
2300
2300
2300
632
790
1490
950
560
1610
1035
575
3
3
3+2
3+2
3+2
3+2
3+2
3+2
3/8
3/8
3/8
3/8
3/8
3/8
3/8
3/8
9/32
9/32
9/32
9/32
9/32
9/32
9/32
9/32
2760
1510
1760
1760
1760
2430
2430
2430
5510
4410
3750
3750
3750
5070
5070
5070
22.3
27.9
52.5
33.5
19.8
56.8
36.5
20.3