BMS Stabilization Plate

[Codfish]

Another mod I have recently completed is the installation of a Bob's Machine Shop Stabilization Plate. I have been contemplating how to get the most performance out of my Suzuki 140 4S for some time. I considered a new prop but felt the 3x14x17 was pretty close to perfect for my usage needs, which is moderate speeds on normally rough ocean conditions. I wanted more bottom end power versus top end speed. I also wanted to maximize fuel consumption. After hearing from Puter Shark about the BMS plate, I bought one.

I then went about making the plate as efficient as I could. I first ground/polished the entire plate, top and bottom to make it as slippery in the water as possible. I even ground off the Bob's Machine letters and Pat Pend numbers. I did this with an angle grinder/polisher and a Zirconia flap disc, 120 grit, of the type used by welders to grind mild steel or alloys. I also used my belt sander with an 80 grit aluminum oxide belt to reshape the leading edges (made them sharper) and clean up the cast plate.

I then took the plate to the local powder coater and had it done in gloss black, to best match the color of my outboard. Not a perfect match but close. The powder coating also made the surface slippery smooth.

After mounting the plate, I even covered the nut and washers with liquid electrical tape to finish off the color match.

Performance wise I think I am better for all this work. The boat gained about .5 mph and seems to get on plane faster and stay there at slower speeds. Can't tell if the fuel consumption will go down but halibut season will provide the proof. The entire cost was $40 for the plate, $15 shipping, $40 for powder coating, $10 for the grinder disc. So for less than the cost of a new plastic prop I got some excellent performance improvement.

Codfish

 

[fridaysoff]

Codfish,
Thanks for the info. I ordered a BMS Stabilizer plate for the same reasons you did (slower planing speeds) for rough days. I haven't put it on yet, but your message helped make my decision. Thanks,
John D.

 

[Dave LeGear]

The color match turned out well and I got lucky with my Honda since it was pretty much close to the same color as the plate

So keep us updated with your performance gains or losses of the plate install on your combo I would also like to know how it now handles when carving up the water with your 140 on your 210 hull and do the extra rudders on the plate help any?

 

[Genelie]

for me i just used a standard hydrofoil wing thingy. works great I get better hole shots, and as for speed I am like you I could careless about top end speed. Mine is 39 miles thats plenty for the ocean

 

[OspreyVic]

Today was our first trial with a Bob’s Machine Shop True Tracker Stabilizer Plate. Wife wanted to go for a ride around Bird Key, an island near downtown Sarasota where new homes are at least three stories high and many look like hotels. It was a perfect test. The reason I purchased the stabilizer plate was to improve steering when at very low speeds. In the intercoastal waterway in this part of Florida, we have an excess of slow speed zones to help protect the manatees (at least that is what we are told). While in these very slow zones, a v-bottom hull has a tendency to go left then right, so you are always fighting the steering wheel. The stabilizer plate was a definite improvement. We still had to play with the steering wheel some, but it was far better than before we installed the plate. For additional steering help, we lowered the trim tabs. Was the Stabilizer plate worth the cost? Yes. Would I purchase and install it again? Yes. There is no perfect solution to steering a v-bottom boat at very slow speeds, but the stabilizer plate from Bob’s Machine shop certainly helped a lot.

 

[OspreyVic]

Additional update on the Stabilizer plate. We were out again today and experimented more with the trim tabs and different speeds.

At low speeds, with the trim tabs down, there was almost no need to correct the steering. What a fabulous improvement.

HOWEVER, the best news was yet to come. In the past, like many others, I had a problem with the depth finder at higher speeds. It would just stop reading bottom. Now, with the stabilizer plate, we have been able to get up to over 20 MPH and still read the bottom. What a drastic change. There is a spot around eight to 10 mph, where if you try to maintain that speed, the depth finder just shuts down. The turbulence caused by the prop around the depth finder must have improved drastically.

Just hope this helps someone else with the same problems.

 

[mainah]

Stabilzer Plate

Hey Vic,

I'm assuming you have both trim tabs and a BMS stabilizer plate installed. Any feed back on how well the stablizer plate effects performance without the tabs down? Particularly how well the plate influenced planing speed and attitude?

Thanks

Dick

 

[OspreyVic]

Hi Dick, and welcome from Osprey Florida.

It was only 82 degrees today out on the water, just warm enough to not need a windbreaker at 20 to 25 MPH.

In my opinion, the boat planes at a lower speed at lower RPMs. I do want to stress that this is an opinion, not a scientific study. My passenger who has been with me on trip for well over 20 hours total agrees. The boat is easier to keep on course at low speeds and planes at lower speeds without using the trim tabs. The trim tabs further enhance lower speed control and using the tabs puts the boat on plan faster. The fact that the boat planes at a lower speed with the trim tabs up is just an added bonus.

 

[peterturf1]

Sounds like a great improvment in low speed control for little investment just ordered mine will probably have to wait till spring for test as my baby is getting winterized this weekend.

 

[mainah]

Stab Plate

That's my problem also. It'll be another five months or so before my '01 186 makes it back to her slip on the Kennebec River. I too am convinced that the BMS plate is just the thing to improve low speed handling - a priority when getting in and out of a slip perpedicular to the flow - and getting on plane at lower speeds for economy and passenger comfort, all at a low price. Can't beat it!

 

[Codfish]

Hello to All with BMS plate,

After a season of use, I can confirm the slow speed steering improvement. The fuel consumption improvement cannot be confirmed but it shurely is no worse than before the BMS install.

I have noticed however that at high speed, above 20 mph, the steering is not as smooth. By that I mean that when I try to move the wheel slightly to change course just a degree or two, the engine will hang or stay on the same course until sufficient force is applied to get it to move. This makes for some jerky feeling in the wheel and slight annoyance for getting the amount of course change desired. I have attributed this to the additional verticle stabilization fins on the outside edges of the plate. More directional surface area, requires more force to move. Nothing I can't live with though.

Codfish

 

[Dave LeGear]

Be mindful of your trim changes now

Interesting find there on the steering Mr. Codfish. I have not had those issues myself but my hull (190) is different and even then I have a pretty hybrid 190 Bay when it comes to engine mounting and lower unit configuration

One thing I have stated many times in the past and I want to remind everybody again... Is how much increased force you are applying to the stern both positive and negative, when trimming your engine when this plate is installed... I would almost be willing to bet that you do not need as much trim as before due to the greater stern lift.

You almost need to re-learn how to trim your boat again for you can create both greater forces in lift and drag "if" you swing the engine in and out to the same amount as you may have in the past.

I would recommend to new owners of this device to experiment around some more by leaving the engine in more of a zero trim angle and slowly make trim changes and see how those changes in trim, effect your speed on the GPS with "no" change in throttle position for the same amount of RPM when on a plane...