Bimini Tops

[showem]

The new boat I got comes with a bimini top, do you normally open them up when your just stopped or is it ok while your moving? Reason I ask, if its open when your moving it seems you would need some kind of strap/line to tie it from the windshield so it would'nt blow back. Thanks for your input

 

[agallant80]

Re: Bimini Tops

There should be a line or strap or a rod you connect to the windshield to keep the top down while driving the boat. Never, never drive wit the bimini open while the boat is on the trailer. Do you have photos?

 

[rallyart]

Re: Bimini Tops

^^Yep what agallant80 said.

 

[JASinIL2006]

Re: Bimini Tops

I leave my bimini up when moving all the time. As long as the windspeed (boat's speed plus any wind on the water) hitting the bimini stays below 35 or so, it's rock solid. Most biminis I've seen have straps that extend tautly from the forward bow of the bimini to some point on the boat like the windshield or gunwhales. There typically are rear straps that similar attach, although in some cases the rear straps may be replaced by stationary support rods that attach somewhere near the stern.

I don't trailer the boat with the bimini up, either open or folded up in the boot. The bimini always comes down when the boat goes on the trailer.

jim

 

[V153]

Re: Bimini Tops

Yup it should have straps or stiff bars fore & aft. Like so:

The top can stack fwd or aft, just depends which way the main frame is pointing. Lotta fishermen down here prefer they stack fwd.

Yes unless the top was designed for it, it's advisable to lower it at high speeds. Particularly if you're trailering the boat. Always puts a big smile on my face when I see one getting pulverized on the interstate.

Best case is booted & tied to the deck. Booted on stiffs is okay too so long as the fittings are secure. If I'm building a top I know will be hauled down the highway, I always drill & rivet the fittings. When you put that much stress on it you can't trust those lil set screws.

Yes a pic would help.

 

[agallant80]

Re: Bimini Tops

There should be a line or strap or a rod you connect to the windshield to keep the top down while driving the boat. Never, never drive wit the bimini open while the boat is on the trailer. Do you have photos?

Let me clarify what I said about driving with the top up. This spring we went to a ramp and it was two shallow so we decided to go south to another ramp. I was lazy and left the top up while we were pulling the boat to the other ramp. Not a good idea. I ended up destroying it and having to get it rebuilt. I drive around the lake and ICW all of the time with the top open just not when its on the trailer being pulled by the truck.

 

[Home Cookin']

Re: Bimini Tops

If you drive your boat 50 mph on the water top up, into a 10 mph wind, no different on the trailer--maybe even smoother. I've always heard that they are made to take speeds of 50.

One reason to take them down at speed is that it is less stress on them--they shake a lot at speed. And whiel boating, the breeze compensates for the lack of shade.

One reason people put them down to cruise is that they act as a drag. So what I and many others do: keep it down when I run a long stretch say to the fishing grounds; leave it up while sitting or moving, even at high speed, to nearby spots, put it down for a long run home.

 

[QC]

Re: Bimini Tops

Never, never drive with the bimini open while the boat is on the trailer.

I just want to clarify this as well. The issue is the top speed, so if you are simply driving around the ramp towing the trailer, or cruising under a typical top speed then there is no difference between on the trailer and in the water. However!! With straps there is definitely wear/weakening over time and of course the time on the trailer would hasten the wear. I have had one break underway and it can be quite violent and potentially dangerous.

 

[Home Cookin']

Re: Bimini Tops

I agree with QC that "never never" is incorrect. But there is also the low-hanging obstacle one may encounter on a trailer and not on the water--including the garage door jamb!

 

[Frank Acampora]

Re: Bimini Tops



The Bimini on my 21 foot cuddy is about 8 feet long and 6 feet wide. Because it has a slight angle of attack it acts like a wing when at speed. This lifts the boat slightly higher out of the water, offsetting air drag, and with the Bimini up, the boat actually GAINS about 3 MPH. After swapping engines and gaining 10 MPH, this effect quite surprised me the first time I noticed it

Yes, I do cruise with the Bimini up and at speeds near 45 there are no problems. Tie down straps do flutter but twisting them a couple of turns before snapping them in place stops this.

All Bimini tops should have front tie-down straps secured to loops in the deck, and either straps or poles at the rear.

 

[V153]

Re: Bimini Tops

there is also the low-hanging obstacle one may encounter on a trailer and not on the water--including the garage door jamb!

I dunno, summa my customers are purty good at runnin em into stuff whilst still in the water. Gotta love Englewood & all the low bridges ...

Regardless. Bimini's slow you down at least 2 mph. Even when set up perfectly. Add to that the stress on the top.

Not to say you can't sew a top that'll withstand high speed. The one I pictured above has seen speeds in excess of 60 mph. Built another one for a guy that's had his 74 mph.

 

[theBrownskull]

Re: Bimini Tops

I leave the top up when driving around at slower speeds. If I plan on going above 25-30 MPH I take it down or it will get beat to death.

 

[QC]

Re: Bimini Tops

This lifts the boat slightly higher out of the water, offsetting air drag, and with the Bimini up, the boat actually GAINS about 3 MPH. After swapping engines and gaining 10 MPH, this effect quite surprised me the first time I noticed it

I totally agree with this. For me Bimini is about a push, but I have almost stopped posting this point as everyone thinks they slow them down and don't believe it. I don't want to hijack, but if this is true, and both of us believe it, then shouldn't some racers be putting lifting wings on their boats? Maybe the effect goes the wrong way at higher speeds?

 

[V153]

Re: Bimini Tops

Yes you'd think race boat builders might use some type of 'Canard' system to create lift and or keep the sob from blowing over. Far as using a bimini for a lifting wing I dunno. I design my Biminis to break as lil wind as possible ...

 

[QC]

Re: Bimini Tops

I lose no top speed with my Bimini and have always stated it was due to lift offsetting wind resistance. I believe Frank's numbers as well. He's pretty darned 'sperienced

 

[V153]

Re: Bimini Tops

I lose no top speed with my Bimini and have always stated it was due to lift offsetting wind resistance. I believe Frank's numbers as well. He's pretty darned 'sperienced

Fair enough & not doubting Frank, but I never saw any speed increase with the bimini up in any of my boats?

 

[QC]

Re: Bimini Tops

I never saw any speed increase with the bimini up in any of my boats?

You're doing it wrong . . .

 

[MikeB0307]

Re: Bimini Tops

I'll put it up while cruising slow or when stationary but always take it down for long runs on plane and always down, booted, and secured when trailering.

 

[Home Cookin']

Re: Bimini Tops

On my boat I tell anyone who has one to remove the bikini top before we go over choppy water due to the bouncing and wobbling. Once we are sitting still, it's justa question of whether they want sun exposure or not; the straps can be a factor there. When the weather gets chilly, running with the tops off can create sharp points. As for on land, best not to trailer with the tops off due to local regulations.

Oh wait. you said bimini. Never mind.

 

[V153]

Re: Bimini Tops

On my boat I tell anyone who has one to remove the bikini top before we go over choppy water due to the bouncing and wobbling. Once we are sitting still, it's justa question of whether they want sun exposure or not; the straps can be a factor there. When the weather gets chilly, running with the tops off can create sharp points. As for on land, best not to trailer with the tops off due to local regulations.

Oh wait. you said bimini. Never mind.

Uggh ...

Reminds me Granpappy Jack always called those kinda jokes "groaners" ...