Help on 22 Cruiser Motor Selection

Hey all,

Well here goes...since y'all are bantering my name around! :wink So for Work Release and Others...

I've been aboard I don't how many CD22's, I know lots of folks that have them and I've rigged so many I've lost count. I've yet to meet an owner with a 4-stroke on the transom (of any make or model) that didn't just love his/her boat. It's darn near impossible to make a bad choice anywhere in the 75 to 100 hp range in any combination.

There's no reason to go to the Honda BF50's (over the 40's) unless you want them. They don't do much for the boat except add about 3 knots to the top end; a speed that's rarely used on most CD22's. On the other hand, there's no reason not to get the BF50's if they're your desire; there's no particular downside to them other than the extra loot. Put what makes you smile back there...after all it's a pleasure boat! :teeth

My personal preference is for the 40's; I like saving the extra money and I feel their performance is more closely matched to the CD22's characteristics. For instance, a very common cruise speed is in the upper teens; that puts the twins just at or under 4,000 rpm. The BF40 develops its peak torque at 3500 rpm; the BF50 at 4500 rpm. If we're at 4000 rpm pushing up the backside of a wave, as the engine rpm drops (from the additional load), on the BF40's the rpm is dropping toward peak torque and away from peak torque on the BF50's. In essence you're a bit on the 'backside' of the power band on the 50's and have to 'catch up'; the BF40's are ready to pull at that rpm.

NOTE: this is subtle stuff; for me it's a matter of optimizing the performance of the boat for the owner and the boat's intended use. So, if the boat's intended use is primarily light loads and higher speeds (maybe it lives on a lake) I'd happily recommend the 50's. It's also about not recommending a more expensive solution just for the heck of it; if you want it go for it. Most folks would never know the difference between running the twin 40's versus the twin 50's until they have lots of hours with each and even then I doubt that the comments would be negative either way. My philosophy is why pay for more then you need...unless you want it; then it makes perfect sense to go with the bigger engines. Nothing's worse than wishing you had made a different choice every time you go out in the boat.

I particularly like the choices in the Suzuki/Johnson line up at the moment and I'm a confirmed Honda lover! The advantages for the CD22 are that they have much better alternators than the Honda's (significantly; which is really nice when you're charging batteries after running lights, the Wallas, inverters, the stereo, etc) and they have EFI (I've not had too much trouble with Honda carbs but there's no denying it's awfully nice to just turn the key and start). A pair of Suzuki 40/50's (which I understand the factory now has) would be a good choice but I particularly like the 90 hp choice as it's a 1950cc engine (350cc more than the Honda 90...more torque and load moving capacity) and has a BIG alternator.

There's absolutely nothing wrong with a Yamaha either but the factory doesn't have them. And in the case of the F75/90 they're pretty much the same as the Honda BF75/90...4-cylinder, 4-carb, etc.

And yes, having twins on the CD22 does offer more maneuverability than a single; the question is how much more do you need than the single offers? This is a tough question. I've never been in a situation with a single that having twins would make significantly better. More convenient at times yes; but less convenient at others. I certainly wouldn't make the choice solely based on maneuverability. Sometimes KISS is good.

There isn't enough torque from the two small BF40/50 props to amount to anything when it comes to handling the boat with twins. If you absolutely nail the throttles with twins it still will not induce a torque reaction...it just ain't there. Counter-rotation just isn't necessary. A normal cruise prop going in the forward direction is more efficient than the same prop in reverse; this has more effect than torque steer when maneuvering the twins. With the wheel centered the boat will turn more to the forward direction and away from the motor in forward gear with the throttles at idle; it takes just a bit of throttle on the reversed engine to get a centered spin.

This is a bit of a non-issue since any wind will affect the CD22 a lot more than the props do as it slides quite easily.

Ok, as much as I'd like to finish this novel I've got to go to work (groan!). Later.
 
There's no doubt about it, Les is the Dr. Phil of outboard motors and boats.
It's always nice to read your posts, you have a really neat gift on how you explain things. :idea :idea :idea :thup
Jon
 
Thanks everyone that had input on this subject, and thanks to Les, very informative stuff from a expert.
Sounds like it I will be satisfied with either choice, but I believe I will at least stay with the Honda brand. Honda has a proven track record and I have haven't talked to a dissatisfied owner. I don't want to be a tester for a new improved brand name, Ill wait until they have a tract record. I have finally setup a test ride on a 22 cruiser with twin 40's and will make a discission, will announce the outcome.
Jim
 
Good evening everyone,

I just wanted to add one very important tidbit to Les' great essay. The alternator on an EFI engine is larger because you have to run one or more fuel pumps, injectors, ignition, and microprocessor. The remaining energy is there for battery charging and whatever toys we want to add to the boat. Another aspect is what is the charging curve related to engine rpm. Mercury recently dropped the output of some of their charging systems to add significantly to the idle and low speed output. Most midrange outboards only put out a couple of amps at idle.

40 amps is the largest under flywheel alternator I have seen. OMC used one for years on their V6 engines. They got hot and I have replaced a good many of them. Mercury went with a 40 amp system on their V6s that used two 20 amp stators and regulators in parallel making a redundant system. Merc started using a belt driven 60 amp alternator on the 3.0 EFI and later on all Optimax product.

Beware of sales hype when talking to salesmen or reading motor brochures. A 20 amp (recently reduced to 18 amp) alternator on a 40 Merc EFI sounds impressive. About half of that output is already spoken for!

Best wishes, Randy.
 
I still have trouble with this statement :?
The BF40 develops its peak torque at 3500 rpm; the BF50 at 4500 rpm. If we're at 4000 rpm pushing up the backside of a wave, as the engine rpm drops (from the additional load), on the BF40's the rpm is dropping toward peak torque and away from peak torque on the BF50's. In essence you're a bit on the 'backside' of the power band on the 50's and have to 'catch up'; the BF40's are ready to pull at that rpm.
Click to expand...

It's true that the torque of the Honda 40 peaks at 3500 rpm and the 50 at 4500 rpm. Where do we get the idea that at any rpm the 40 has more torque than the 50 based on that? At any rpm the engine with the most torque will pull more, accellerate faster. Torque wins.

At 3500 rpm what's the torque of the Honda 40 and Honda 50? We know the 40, as that's the listed peak HP. What's the 50's, less or more?

I admit this is purely academic 'cuz on water reports indicate virtually no performance differences between the two motors, but the assumption the 50 has less torque than the 40 at any rpm still buggs me. 8)

-- Chuck
 
From Les Lampman- Feb. 26, 2004


Hello Chris and Janet,

Since I'm usually the one telling people that either setup (single or twins) makes a wonderful boat and to just install what 'speaks' to you I'll play devil's advocate today and let you develop the arguments.

I suggest if you're really on the fence; go with a single main engine and a kicker motor. Why?

1) In the long run simpler is always better and less expensive.
2) It's less expensive up front to go that way; rigging for the twin engine setup is much more expensive with two of all the gauges, the key switches, the remote controller, the control cables, the props, the tiebar, etc. With a single/kicker there's much less complexitiy since the kicker doesn't get all that rigging paraphenalia. With the single main you have a simpler dash layout and just one lever to mess with when manuevering.
3) Reliability is a non-issue; you're as likely to see a broken down four-stroke motor (of any make) as you are a new car. Usually it's a flat tire that puts a new car on the side of the road; for us it's a whacked prop.
4) If you're going to hit something (and that's the reason most boats get stopped) you're better off with a single and kicker; with twins on 24" centers the likelihood is that if you hit one prop you'll hit both; in fact, that close together, one twin usually throws the debris into the other. With a single/kicker the main engine's prop may get whacked but the kicker is safe and sound tipped out of the water.
5) With a single/kicker you can have a swim step and ladder on the transom. Very nice for getting in and out of dinghies, getting out of the water if you find yourself there by mistake (or on purpose if you dive), very nice for changing the prop on the main engine if you need to.
6) If you or anybody that's going to be routinely aboad is 'pitch sensitive' (in a mucical sense) twins are going to drive them nuts unless you keep them synchronized. I've come close to grabbing the throttle my self (with someone else at the helm) on a few boats when the 'thrum' of unsynched motors litterally had me clenching my teeth.
7) There's a lot of controls to mess with on the twin setup...two key switches, two trim switches, two control levers, two trim tab rockers; getting the boat trimmed out takes more effort that a single engine does.
8 ) Big engines last longer than little engines. That is, there is higher potential to put more hours on a 75/90 than there is to put hours on a 40/50. I'd be the first to admit that doesn't usually come into play for most of us but if you get a lot of hours on your engines the Honda BF75 will outlast the BF40's by about 50%.
9) The electrical system on the twins is more complex and takes more operator intervention. The alternators on the twins can not be paralleled or you run the risk of 'backfeeding' into one of them and literally burning the charging coils. That means knowing what you're doing with the battery switch. This is much easier with a single engine. The single can charge a single battery better then the twins can charge two batteries (since their output can't be combined).
10) If you're in the San Juans and you have an anchor, a VHF, and a Vessel Assist card you're good to go if you're really in for a bad time. The image of fighting your way home on an 8-hp kicker is a bit overwrought. The 8-hp kicker will push the CD22 along at hull speed (about 5 knots) and you'll be traveling just like every sailboat out there. Yeah it's slower than you usually go...what's you point? My dad brought a heavy 26' power boat back from Barkley Sound (on the west coast of Vancouver Island) to Whidbey Island on a Honda BF100 (which is the BF8; the old motor was rated for horsepower at the flywheel)...best mileage he ever got with that boat for sure! And that boat easily wieghed twice what a CD22 does.

When you're selecting options plan for the future. For instance, we don't deliver CD22's without hydraulic steering. I know that the maintenenace on the hydraulic steering is significantly less and easier than cable steering. With cable steering I will see you in a few years to replace the steering cable and probably sooner to free it up after it sits over a winter. If you use your boat a lot you're probably going to get interested in an autopilot; the prices have plummeted and they're a handy item to have aboard (the seagoing equivalent of cruise control!). Adding that to a boat with hydraulic steering is relatively easy and a much better system than is available with mechanical steering. Steering effort is not the big thing; the mechanical steering isn't so bad. I have noticed though that more of the crew volunteers to steer with hydarulic steering versus mechanical (it is nicer); at least until the autopilot gets installed.

Get the trim tabs...they make a world of difference.

Get the electric wipers on both windows; otherwise you look like you're filming an exercise video...up, down, up, down...you can't reach the port wiper from the helm seat. And since most folks mount thier main nav screen in front of the helm (usually something like a Garmin 188C, a Raymarine RL70CRC, or a Furno 1722) it sometimes isn't easy to reach the starboard manual wiper either.

If you want the cat's meow get the Camper Canvas. It's like getting suite at the hotel instead of just a room. All of a suden you have a protected space to come in out of the rain or wind (or both) and get the wet gear off before going into the nice dry cabin. You'll have more room to store stuff with weather protection in the cockpit (who doesn't need more space?) and you'll have a place at night for the portable head to live (and get used). Besides that, at a C-Dory get together the boats with camper canvas are the most popular! Gives you a nice lounge space.

I'm out of time...unless this 'flips the coin' for you I can do the next message with all the reasons I think you should get twins!!!
_________________
Boat Les...on Whidbey
 
hi all
i am running twins and they offer a more stable platform in a chop or steep swells and will get you back easier if you are caught out in a bad blow,than a single and a small kicker. i love the twins as a safety feature on lake Superior which is known to make its own weather on occasion no matter what the weather radio says...........folks that run singles have very good reasons for their choices too! so nobody is wrong! a person just needs to determine their individual needs and then rig her out.
ras
 
Chuck S":1fypvzvg said:
It's true that the torque of the Honda 40 peaks at 3500 rpm and the 50 at 4500 rpm. Where do we get the idea that at any rpm the 40 has more torque than the 50 based on that? At any rpm the engine with the most torque will pull more, accellerate faster. Torque wins.

At 3500 rpm what's the torque of the Honda 40 and Honda 50? We know the 40, as that's the listed peak HP. What's the 50's, less or more?

-- Chuck
Click to expand...

I'm assuming you mean that at 3500 the BF40 is producing peak torque, not HP.

If I ever have more time I'll try and get somebody at Honda to see if the engineering department has actual torque curves.

In the meantime I'll agree that the the torque values on the curve are an assumption (albeit an educated one) on my part. The logic is that both motors essentially produce the same torque since they're the same displacement (and I'm assuming the engineers wanted to maximize that torque at their respective peaks). It stands to reason (at least in my mind) that if the BF50 peaks at 4500 then at 3500 it must be some lower value (given the way the BF50 performs on the water I doubt the torque curve is all that flat). The BF40 peaks at 3500 and the assumption is that it's some lower value at 4500; its on the water performance would suggest the the curve does not fall off a lot at the upper end (at least until it's over 5000 rpm). I don't in fact know (and haven't said as far as I know) that the BF40 does have a higher torque value at any given rpm than the BF50. What I have said is that the BF40 tends to be a more tractable engine and pulls more smoothly when running in the mid 3000 range because it s running around it's peak torque (the flatter part of the curve) and not, as the BF50 would be, well below it's peak torque and on a more sloped part of the curve; particularly as a set of twins where the typical cruise rpm is under 4,000 rpm on a CD22 in other than smooth water conditions. I do not agree with a blanket statement that an engine with the most torque at any particular point wins. There are too many other variables such as the shape of the torque curve and response to that to consider. If you take one point in isolation the argument may stand up but engines in the real world don't operate in isolation from their environment.

Given that I'm trying to maximize the return-on-investment for my customers and to hand over the keys to a superbly running boat I can't in good conscience tell them they need to buy the BF50's in order to have a properly running boat. Except for emotional reasons (that are perfectly valid) there is nothing to be gained by utilizing twin Honda BF50's on a CD22 for the typical CD22 owner/operator as opposed to running with twin BF40's. I'd rather see them save the $1300 (or whatever it is at their dealer) and put it towards something more useful; unless they just want the BF50's, then it's their choice and their checkbook.
 
Here's Les Lampman's second installement on the twins vs. single motor with kicker discussion:

It's me again.

I'm not sure I have quite as much time this morning to type as much as I did on the Single Engine Cause! Aren't you glad!

First, to Scotty who asked about the Anchor Deck Pipe and windlass. You are correct; you do not need to order the Anchor Deck Pipe option if you're installing the windlass. Dave's answer threw me a little but I think he was saying that if you already have a boat with the Anchor Deck Pipe you can still add a windlass.

So why in the world would you want twins?

1) The number one reason has to be the "cool" factor; hardly anything looks better that a pair of engines hanging on the stern. Too many folks discount this as being 'silly' and try and justify it on a 'technical' basis; but if looks don't count what attracted you to the C-Dory? Or your car? Or whatever; you get the idea.

2) IF you're going to lose an engine and IF you're a long way from help (and some C-Dory's do go to some very remote areas) being able to get to help at a higher speed (say 8 knots rather than 5) while sitting at the helm and operating the boat as you usually do would be nice (you have visibility, you have your instrumentation and electronics, you're warm, and you have steering and shift controls at hand). So, my general rule is that the need for twins (from a backup standpoint) is proportional to the distance from help. Losing a main engine is still not a high probability BUT it can happen and the farther out in never-never land you are the more comforting it would be to have that backup.

Keep in mind however, that the two main reasons for not having motive power are that you hit something (and with twins very likely damaged both props) or you have a fuel contamination problem (that will most likely affect both engines since installing a truly redundant fuel system on a CD22 is a bit of a space challenge and overkill for most). If you're travelling afar you should be prepared to change props and filters on your own (and a small reserve of quality fuel wouldn't be bad in truly out-of-the-way places).

3) Twins make you 'feel' good...and don't pooh-pooh this either. Happiness is being comfortable and you're not comfortable if you're scared or worried. So if having twins on the back raises the comfort level and your sense of security that's a darn good reason to have them; sure makes boating a lot more fun.

The second side to this feel thing is from a 'smile factor' standpoint. If having twins on the stern makes you smile every time you see the boat then you did the right thing. These are pleasure boats; they're supposed to make you smile. Nothing's worse than buying a new 'thing' and then wishing you had made a different choice. This usually happens because you thought too much and over-analyzed the darn thing (this is really a 'guy' problem). Listen to your heart, to heck with the technical details; all these various engine configurations work super well...that's why there are so many happy CD22 owners.

4) You're a gunkholer (I am). If you like to sneak into tiny little places and go where none dared go before, or you like to cruise marinas and stick your nose down each float then you'll appreciate two things about the twins....1) you can tilt one engine up out of the water (usually the port because of the steering linkage) and 'tip-toe' in with the other (even with that one trimmed up a bit). If you do smack something then you've just got one prop to deal with. You can do this with a single and kicker but you don't get to sit at the helm with full control and the sounder right in front of you since you're in the cockpit running the kicker; which also means you're in the back of the boat where you can't see as well and 2) you can literally turn the boat in it's own length. This is really nice when you get into a dead-end in a marina and need to head the other direction, or when the wind is blowing and you want to dock. To really get the most from your twins (from a handling standpoint) you have to practice; if you don't you might find that you'll get yourself into more trouble trying to use both engines (other than in unison) than if you left one engine in neutral and just used one for maneuvering.

5) If you're doing the Power Squadron or Coast Guard Reserve thing (or just good Samaritan) and have a disabled boat along side you'll appreciate the ability to use differential power with the twins.

6) Profile and visibility; the twins are not as tall as the single engine so when you look back over the stern you don't see one tall motor sticking up in the center. Rather you're looking over the top of two shorter motors (better for sunset viewing from the cockpit). And it's back to the 'looks' thing again; some folks just prefer the lower profile of the twins when viewing the boat from the side (or any angle for that matter).

7) For fishing you can just troll on one of the twin engines; you don't have to worry about steering linkage, etc to the kicker motor; so you can sit at the helm where you have your depth sounder and full steering, speed and shift control. One twin running will slow down pretty darn well. You can troll on the main single but it's sometimes hard to get the speed down. The advantage of running from the helm can also be a disadvantage in that you must run from the helm since that's where the steering and controls are. This can be mitigated to some degree by having an autopilot with a remote in the cockpit; that's a very nice setup! And helps with cruising aspects as well. This is a very subjective area...it really depends a lot on how you fish. Or even if you fish.

8 ) The twins are slightly more efficient in the low and mid-range speeds since you have two props that constitute more blade area in the water than the single larger prop and you get better response. For cruisers with heavy loads this is a good thing. The flip side is you'll give it up at higher speeds where the extra drag of the twins comes into play.

I've probably missed a couple things I'm sure. In the final analysis what I find is that I can find more technical reasons for choosing a single and a kicker motor; I find more emotional reasons for choosing twins. This coincides greatly with what I've seen customers ultimately choose. Pure cruisers and those going to remote places tend to choose the twins; fisherman and local boaters tend to favor the single. These are, of course, just generalities and I personally know of several 'exceptions'; new boaters (in general) tend to gravitate to the twin configuration since their experience level and therefore their comfort level is not very high. [Unless you're an engineering type or technical type; in which case you're going to analyze the heck out of the thing anyway!]
_________________
Boat Les...on Whidbey
 
Les --

Really all I'd like to see is the 40's and 50's torque at 3500 rpm thru 4500 rpm. In this range the 40's curve must have a downward slope (or it wouldn't peak at 3500 rpm) and the 50s must have an upward slope. Torque curves are normally fairly flat. Horsepower, of course, is merely a mathematical formula derived from torque and rpm, so it favors rpm on high revving engines like these.

Angle of slope would, of course, be interesting as would the complete graph of both engines.

I wrote Honda Marine about this and was told to contact my dealer :wink

-- Chuck
 
I give up. Too much information. I'm going to add a 90 single to the starboard of my twin 45's and a 9.9 kicker to the port side. Need some volunteers to sit on the bow to keep it in the water. As long as I don't light them all off at once, I figure I'll be OK. Someone might as well notify the USCG right now...
 
Captains Choice Charlie, I think you'll be going around in circles with a 90 hanging off to the side. You need to mount it in the through the floor in the cockpit, perhaps like a sail drive....but....then...if you have trim tabs it should work....or maybe a bow mounted trolling motor would help ballance things out, it could also provide a means to get home if the other engines should fail :)
 
How about the 90 on the centerline at the stern, the 45's (which I already I have, sunk cost so to speak) on the port and starboard quarters, and the 9.9 on the bow as a thruster? Wow, what a package!! And to think I'm a Naval Engineer, and have built real ships too! Scary for all you that have sons and daughers at sea!! Promise I don't mean a word of the forgoing!!

Had nothing to do with the Titanic or the Atocia by the way.....

Charlie (Sally disavows all connection with this post)
 
Well, I'm the guy who started this thread and reading the last few posts it sounds like C-Dory may have to start engineering a new boat with these new motor selections. There were so many discussions on various choices it sounded like a toss up to me. I won't keep you waiting on what I decided on. Twin 50's Hondas. I went with this choice for two reason. Number 1, two times on different boats I have had my main motor go zonkers on me. Each time I had a kicker but still had difficulty getting back to Port with bad weather conditions and strong tides ( not fun ). Number 2, alot of times traveling up to B.C. fishing I'm usally loaded up to the hilt with gear so I wanted to maximize my horsepower capacity. Either way I knew I will be happy with this new 22 cruiser, should get delivery in about one week give or take a few hours. This is a great web site and I plan on meeting some of you salts on a outing.
Fish-on, Jim
 
Butch,
I'm bringing this site up again, since you are asking about twins vs. singles. There is quite a bit of information here on all 3 pages of this thread. I'm sure this information is applicable to your 25' as well.
 
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