Re: Newbie Boater needs advice on oars
Welcome to iboats.
A 12' aluminum boat WILL NOT handle a 25 HP motor...... maybe a 10 HP you need to check the rating plate before you get hurt.
Here is the proper oar length formula...... C&P from another web site. iboats sells oars in the Marine Store.
Shaw & Tenney Oar Length Formula for Correctly Fitted Oars
Inboard length of the loom equals ? the span between the oarlocks + 2"
Total length of oar equals 1/7 of inboard length multiplied by 25
Leverage Ratio is 7:18
Distance from the center of leather to end of grip equals 7/25 of the total length of the oar
Here is a c&p from the USCG regulation available here
http://forums.iboats.com/showthread.php?t=191283
Sec. 183.53?Horsepower capacity
The maximum horsepower capacity marked on a boat must not exceed the horsepower capacity
determined by the computation method discussed in paragraph (a) of this section, or for certain
qualifying boats, the performance test method discussed in paragraph (b) of this section.
(a) The maximum horsepower capacity must be computed as follows:
(1) Compute a factor by multiplying the boat length in feet by the maximum transom
width in feet excluding handles and other similar fittings, attachments, and extensions. If
the boat does not have a full transom, the transom width is the broadest beam in the
aftermost quarter length of the boat.
(2) Locate horsepower capacity corresponding to the factor in Table 183.53.
(3) For a boat with a factor over 52.5, if the horsepower capacity calculated in Table
183.53 is not an exact multiple of 5, it may be raised to the next exact multiple of 5.
(4) For flat bottom hard chine boats with a factor of 52 or less, the horsepower
capacity must be reduced by one horsepower capacity increment in Table 183.53.
Table 183.53?Outboard Boat Horsepower Capacity
[Compute: Factor = Boat Length X Transom Width]
If factor (nearest integer) is 0-35 36-39 40-42 43-45 46-52
Horsepower Capacity is 3 5 7.5 10 15
[Note: For flat bottom hard chine boats, with factor of 52 or less, reduce one capacity limit (e.g. 5 to 3)]
