RT260 RIB Outboard Weight Limit

dbsea

Well-known member
Joined
Oct 1, 2021
Messages
1,063
Fluid Motion Model
R-23 (Outboard)
Vessel Name
HALCYON
MMSI Number
368365270
I have the RT260 RIB that came with my 2016 C-30CB, it seems like a good dinghy. I also got a brand new 6hp Tohatsu 4 stroke outboard when got the boat in October, which weighs 55lbs. I've found that the dinghy struggles to plane with the 6hp, especially with two people. If I use the tiller extension and sit forward, it will plane with just me and go along at a nice clip. The plackard in the dinghy says the motor weight limit is 66lbs. Is this just a "recommendation" or would I be getting into trouble if I went bigger, to say 8hp (81lbs). The other alternative is to find a used 2-stroke outboard, they are much lighter and usually have more torque from two cylinders. I need the speed / planing because we often have to take our dogs to shore or go from an outstation to some other place we are visiting.
 
Dave,

I also have a Tohatsu 6hp, and will be trying on our "yet to be delivered" R27OB with its RT 260 RIB as well.

On our previous boat, we had a Mercury 260 RIB, very similar to the RT model. I had tried various "trim" pin positions to better handle solo operation and not end up with "bow in the air" condition. Having it trimmed vertical, or slightly "down" was my best recollection of what I preferred. I could slip along pretty good, but don't recall being fully "on-plane" like you would in a 14' w/40hp.

More power is nice, but the 8hp vs 6hp is marginal, while the weight isn't. External gas tank mounted forward would help, dinghy anchor and chain/rode fwd will help.
 
Thanks Cliff. I agree with you that from a HP perspective 6 to 8hp is not a big jump. I believe the real difference comes from the # of cylinders in the engine and the torque created. Older 2 stroke outboards are often better at the task of planing, due to their lighter weight and usually having 2 cylinders, down to the 6hp size. A comparable 6hp evinrude two stroke actually weighs 6lbs less than my 4 stroke tohatsu. I'm not sure the hassle of a two stroke is worth it, however. I'll probably just plod along with what I have until I'm ready for a bigger boat that comes with a more robust dinghy and outboard setup. ;-D
 
Regardless of dinghy capacity, the extra weight of the 8hp astern may not help you plane even with the additional power.

Every 4-stroke + dinghy I've ever owned hasn't been able to plane if I'm the only passenger (vs. having additional weight forward), unless I'm using a tiller extension OR those bolt-on "fins."
 
Thanks for all the tips. Mine will plane and hum right along if I’m in the forward seat and it’s just me, but won’t with a second person. I ordered the fins to see if that helps.
 
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