I just picked up my first boat this spring (Tracker 190/115 Opti),  and have put some time in trying to learn it. I'm struggling trying to find the sweet spot on trim, though. If I trim out just until the steering starts to lighten up, I'm around 42mph/5k rpm in light chop. I can continue trimming out and get to 44-ish at about 5250 rpm, but the boat's beginning to torque left at that point with each tap up on the trim switch, and will bite and pull right the first time I trim back in. I can still gain a bit of speed by trimming out more, but the boat starts to feel "loose" so I don't go farther (maybe that's just me being inexperienced). I have a 22p Laser II currently, with motor in lowest position (no jackplate). Any advice or suggestions?

Maybe @Way2slow or someone can give you and exact answer.  I'm just gonna say, i personally and not gonna sacrifice control... so when you get to the point of losing steering or boat getting loose.  42. Mph is respectable on that rig.  

 

I'm spoiled I have a nice Jack plate and mine was set up for optimal performance before I even got it.  and even tho I can get 70 mph outta my boat i rarely go over 55.. especially once it starts getting cold.  

Tin boats respond a little different to trim than glass boats with riser hull, and I'm not a tin boat person.

I trim a glass boat until you feel to bow lift and the hull breaks loose, making the boat feel almost likes it's floating on air.  Not sure a tin boat will do that, having never driven one, other than smaller jons.

Usually the key indicators for being over trimmed are, the sound of the motor will change to kind of a hollow sound.  The rpm's increase but the speed doesn't.  The boat gets an unstable feeling and chine walk is uncontrollable (this one I don't think you have to worry about.  A lot of times you can look at the prop and it will form places about the size of a 50 cent piece on the low part of the blades that looks almost like it was sand blaster after they have been run a while.

Since I don't know anything about your hull, I can only shoot from the hip on suggestions, most tin boats don't do as well with high rake props.  They are designed to get more bow lift for boats with riser hulls. 

Another thing, your boat is over propped for my likings.  I like to see my rpms right at max at WOT and normal load.  That makes a huge difference in hole shot overall performance.

Now, some of that could be caused by setup problems, like the motor too deep and not enough setback etc.  Don't think for a minute the dealers set one up properly.  That takes more time and money.

 

 

Like Way2 I think your motor might be a bit low.  Also, as previously pointed out aluminum boats generally have a different hull design and aren't designed to run on a pad like a fiberglass hull.  You want your motor to run most efficiently as it reaches close to it's maximum recommended RPM range.  However, the ability to control the boat is the most important thing so everything you do should make it safer to operate.  If your max RPM is 5200 then a lower pitch prop will give you an increase in RPM's.  What I wouldn't do is change everything at once because if things don't get better you won't know what to change.  I would:

 

1)   Check the trim tab (it's right above the propeller).  It may be angled and that is contributing to your steering torque problem.

 

2)  Try a 20 or 21 pitch prop.  This is going to get your RPM's up.  It might not help the handling but at least your motor will be running closer to it's recommended RPM range.

 

3)  Move the engine up one hole, or add a jackplate.  Part of the problem with the increasing steering torque is that too much of the engine may be in the water and that's what's making it harder to steer.

 

Do each of these one at a time.  That way you'll know the effect each change has and whether to keep that setup or go back to your baseline.

 

 

115 Optimax usually are set up with 20 pitch Laser 2 props. Trim problems may be do to inexperience as you are guessing proper feel. Torquing to 1 side is usually a result the the tab not adjusted properly, move slightly toward the direction the torque feels heavy.

Weight distrubution plays a big role to keep the boat balanced at speed, heavy items in the rear behind the driver light weight items in front of the driver. No reason to carry around water in the livewell.

As far as prop depth is concerned start at 3 1/2" prop shaft centerline below and Paralell the center of the plane pad.

Tom

Thanks for the advice, folks. First off @Teal, I 100% agree about control. That's exactly why I haven't tried to continue trimming even farther out, due to the looseness of the boat/steering.@Way2slow @KYRANGERMAN When I'm not trying to experiment with it, I usually just get the boat on plane (it does easily), and then trim out until the steering isn't "heavy" anymore.

Can you tell me the effects of raising the motor? I understand it'll reduce drag, but I'm guessing it'll also affect steering and the optimal amount of trim needed, as well? I may start with this and then tinker with prop selection if necessary.

11 minutes ago, WRB said:

115 Optimax usually are set up with 20 pitch Laser 2 props. Trim problems may be do to inexperience as you are guessing proper feel. Torquing to 1 side is usually a result the the tab not adjusted properly, move slightly toward the direction the torque feels heavy.

Weight distrubution plays a big role to keep the boat balanced at speed, heavy items in the rear behind the driver light weight items in front of the driver. No reason to carry around water in the livewell.

As far as prop depth is concerned start at 3 1/2" prop shaft centerline below and Paralell the center of the plane pad.

Tom

Right on the money...

As others have said mod v aluminum boats handle a lot different than fiberglass boats.

I own a Fiberglass Ranger Z175 with a 115 mercury pro xs. It will hit right at 50 mph top speed, and still very manageable.

My brother in law has a tracker 190 with the same motor. it had nearly the same problems you are having. 42 mph top speed at 5200 rpm. anything more and the boat would get real loose and hard to handle.

Come to find out they put the motor too low. he had it raised up one set of holes and dropped down one pitch size on the prop.

he can go around 45 mph now at 5600 rpm and it handles a little better. It still gets squirrelly if he over trims it, but much better than where he started.  It is still nothing like my fiberglass boat.

 

 

@WRB you got finished before I could finish mine. Just to be clear about my use of "torque"... I don't actually notice it pulling hard right when trimmed in, or hard left when trimmed out. But it definitely "digs in" to the right when I'm trimming back down. One person, without seeing it, guessed I may be trimming the trim tab out of the water, and it's catching when I'm coming back in - but I honestly have no idea ?

I dought you are over trimmed to the point the tab is above the water. Watch your water pressure gauge for pulses indication air is being sucked in. 22" pitch is too high for you rig and I believe you are fighting the prop.

Tom

The easy way is to raise your motor one hole and test it.