2 stroke motor question Yamaha 8 or Merc 9.9

[cisco kid]

Hi Guys,

New to site want some feedback

I am buying one of the inflatables below for lake/river and some ocean use around an island we have friends on to fish the bays.

BRIG Baltic 310 97lbs
Zodia Cadet 310 93lbs

I have limited space as to how I have to transport either once I buy until I buy an SUV again in 2-3 years, for now it is a 4 door car. Also keeping motor weight down makes it easier to carry once to our place of departure.
I am not interested in 4 stroke at all.

Yamaha 2 stroke 8hp 100:1 premix 60lbs
OR
Merc 2 stroke 9.9hp premix 50:1 80lbs

Around my area the Mercs can be found used at decent price, the Yamahas very hard and prices are high used.

Will the Yamaha be enough with dole fins to plane 3 people w some gear. I can get the inflatable with solid floor into trunk with good space for 8hp Yamaha ,gas tank rods and some extras in bag like life vest boots that type of thing. If I go 9.9hp motor I will eat up some space and have a heavier motor to haul around. Should I sacrifice some space for the bigger motor. If I have to buy new price is the same for either motor $2300 Canadian plus tax. I plan to go with a 15 litre tank. I also like fact that the Yamaha burns less oil.

Primary use of the inflatable will be fishing and cruising lakes with my son and wife or 2 adults and 2 kids on weekends for some camping

All feedback welcomed

[Fenlander]

My experience of inflatables just over 3m is that even a 9.8hp (Tohatsu in my case) only gives decent performance with two adults and a very small amount of gear or one adult and two smallish teens plus gear. To be honest once you get carrying yourself, wife, two kids and camping gear you'll really need a 15hp.

But that's no problem if you're considering a 9.9hp as in many makes the 9.9hp weighs the same as a 15hp so you might as well go for the 15hp. The only exception I know is the Nissan/Tohatsu 9.8hp which weighs the same as a 6hp.

[mister p]

I have a 285 Zody with a ply floor and Vee hull. With 30 litres of fuel, myself (80kg), and my 13 and 7 yr old sons plus kit for the day, she will hold 20 knots on the plane using our 8hp Mariner.
We use it on the open water and the top speed is held just off w.o.t. Maybe we got lucky with the Mariner, because it is very sweet. We regularly hop across bays where she's held flat out for twenty/thirty minutes with no problems. We love some chop as the Zodiac takes to the air readily and the boat carries enough momentum for the engine not to struggle one the prop is wet again.
Appreciate the boat is a size down but hope that gives you some perspective.

[Max...]

Originally Posted by mister p

I have a 285 Zody with a ply floor and Vee hull. With 30 litres of fuel, myself (80kg), and my 13 and 7 yr old sons plus kit for the day, she will hold 20 knots on the plane using our 8hp Mariner.
We use it on the open water and the top speed is held just off w.o.t. Maybe we got lucky with the Mariner, because it is very sweet. We regularly hop across bays where she's held flat out for twenty/thirty minutes with no problems. We love some chop as the Zodiac takes to the air readily and the boat carries enough momentum for the engine not to struggle one the prop is wet again.
Appreciate the boat is a size down but hope that gives you some perspective.

That is surprising to say the least - many of us run a 9.8 Tohatsu on a 3 - 3.4m SIB and would be looking at more like a 15 kt absolute max WOT with a similar loading...

(I've got 17kts with just myself and my 8 year old and minimal gear).

To the OP I would say a sub 10hp engine on that rig with that loading is a recipie for disappointment and as Fenlander says a 15hp will be the minimum needed.

[mister p]

As I said, it was for perspective and what can be achieved if one is extremely lucky with an engine.
I too would recommend a 15.

[cisco kid]

thanks for the replies. as usual getting larger than one is considering is never a bad idea for a motor. my issue is limited space , however i am looking at a used merc 9.9 on consignment, hopi.g it is post 2006 and in good shape. price is 1100 which saves me alot over new merc 9.9 or the yammie 8 which are 2300 cnd plus tax here.

if the merc is good shape and fits i will go bigger but i also want to run w a 15 litre gas tank, just alot easier and carry an extra spare gallon when i may need it.

i may be forced to go w the yamaha and add dole fins, most persons that have given me feedback at boatstores feel the 8 will plane 2 adults and some gear, feedback coming from those using this motor w a similar solid floor inflatable like the zodiac and brig. will post back my findings after seeing the motor.

[willk]

Originally Posted by cisco kid

Primary use of the inflatable will be fishing and cruising lakes with my son and wife or 2 adults and 2 kids on weekends for some camping

All feedback welcomed

I use a slightly smaller SIB with a bigger motor. I have loaded it up and tested it extensively. TBH, I think that your expectations/hopes are unrealistic. Have you put these loads in a 3.1m SIB? I certainly don't think the 8hp motor will perform as hoped.

I also think that the bloke with the 8hp (Misterp) is unlikely to be getting 20kts with the stated load. Just 1 up, maybe...

I'm not trying to p1ss on your parade btw, far from it, just trying to help avoid a disapointment.

[cisco kid]

Originally Posted by willk

I use a slightly smaller SIB with a bigger motor. I have loaded it up and tested it extensively. TBH, I think that your expectations/hopes are unrealistic. Have you put these loads in a 3.1m SIB? I certainly don't think the 8hp motor will perform as hoped.

I also think that the bloke with the 8hp (Misterp) is unlikely to be getting 20kts with the stated load. Just 1 up, maybe...

I'm not trying to p1ss on your parade btw, far from it, just trying to help avoid a disapointment.

I welcome your advice no worries there, I question some of what I have been told by the dealers themselves as it is personal experience and not apple to apple comparison. I feel a 8hp Yamaha 2 stroke will work fine with an adult and kid out tooling around, but add more than that and I see it taking a while to get on plane if it can along with added gear and weight.

I have seen the motor that is for sale 15HP 2 Stroke Mercury 2003 model, all tested and by the shop and good to go but it has hours on it for sure lots of them as it is ex fish camp from a place called Rivers Inlet in BC Canada 300 miles north of Vancouver BC, what a place to go if you have the coin, one day I will do something like that with my son that I know.

My concern is the amount of use the engine has had, even though they have gone over it and inspected and replaced whats required is there anything I should be concerned with other than the usual rattles and oil consumption. Price is right at $1100 CND, I willbe buying the SIB this week it will be BRIG BALTIC 3.15 meters. The motor will follow as I watch used forums for a while longer and if I can not find what I want used I will splurge for a new Mercury 9.9 2 stroke or if there if it is still available the 15hp used Merc, gonna give it up to a month to come up with something.

The BRIG is rated for max 15hp, but what is so nice about the 8hp Yamaha is the weight , 60lbs is just so nice especially for my application where the SIB is being deflated and stored in its downtime

Check out some pics/videos

BC Salmon Fishing Lodge - Rivers Inlet British Columbia Canada

[Fenlander]

I'm with Willk... you really want to think this through before doing the outboard deal or you could be really disapointed. If the load is too great for a 8hp it's not how long it takes to get on the plane more a case of if you can. With our old 3.1m Zodiac and a Tohatsu 9.8 we couldn't plane 4-up (2 adults, 2 teens plus minimal kit). To be honest I was very frustrated being kept to displacement speeds. Once we went to a 3.6m Zodiac with 15hp and carrying the same load we could plane easily with loads of power in hand.

Remember doel fins don't add power they just change the attitude of the boat that can sometimes help with the transition speed to a full plane... but if the power just isn't there they won't help you break out of displacement speed.

So I'd be very wary of a 8hp for your use.

What I don't understand either is why would you consider a 9.9hp in any make where the 15hp weighs the same? If you're going to carry 80lbs about you may as well go for the 50% extra power surely?

[cisco kid]

@ferlander, i will only go 9.9 new if i am unable to find a used 15hp motor that is in decent shape. i have come across one, its an ex fish camp motor w what i am guessing is lots of hours, its prices decent though at $1000 cnd and has been inspected and tuned by the shop selling, any parts needed have been replaced, its a 2003 Merc 2 stroke 15hp.

I figure its a good deal, just question whether i want to keep looking and pass on it for now giving it a but more time hoping i can get something else and if not will grab it. i am kinda caught on going w a new 9.9 or buying a used 9.9 or this 15hp unit. i have taken the 8hp out of the equation just so i do not end up disappointed w performance for my useage.

Are Mercs known to be long lasting engines when used alot but taken care of, i guess thats my concern, the shop tells me they would not offer ut up for sale if it was no "good to go" so to speak.

[thornbackflound]

Originally Posted by cisco kid

@ferlander, i will only go 9.9 new if i am unable to find a used 15hp motor that is in decent shape. i have come across one, its an ex fish camp motor w what i am guessing is lots of hours, its prices decent though at $1000 cnd and has been inspected and tuned by the shop selling, any parts needed have been replaced, its a 2003 Merc 2 stroke 15hp.

I figure its a good deal, just question whether i want to keep looking and pass on it for now giving it a but more time hoping i can get something else and if not will grab it. i am kinda caught on going w a new 9.9 or buying a used 9.9 or this 15hp unit. i have taken the 8hp out of the equation just so i do not end up disappointed w performance for my useage.

Are Mercs known to be long lasting engines when used alot but taken care of, i guess thats my concern, the shop tells me they would not offer ut up for sale if it was no "good to go" so to speak.

I have 2004 merc 2 stroke 10hp,purs like a kitten,shame my porps shite,needs reconditioning,i have it on a very heavy D class commercial 4m sib with alloy floor 2 of us lots of fishing gear i had 10 knotts out of it last time used,remmember my prop is knackered so would get a little more,but 15 i have had on and that was not much faster,but as said my sib is heavy,hope that helps.

[hobnob]

I have a Zodiac 3.1 with plywood floor, and a Yamaha 8hp. It is a fantastic motor; it is 90% of the time running WOT, and reaches 20mph on GPS with me + 40l of fuel (i.e. 110kg)

With two small children and wife, it will still plane. I'd like a 9.9 (which is the max rated outboard for this boat) but it would weigh more, and wouldn't add much to the boating experience. 20mph on a choppy river is pretty bouncy for kids.

[cisco kid]

I settled for getting a Merc 2 stroke 15hp, maxxed out the SIB, should fly, have got the Brig Baltic SIB out on a lake this weekend, everything went smooth, now to find a trolling motor for the lakes that do not allow gas.