Wind Wing/bimini Top question

Siggymanx33 · Post by **Siggymanx33** » Wed Oct 26, 2005 2:27 am

I had a bimini top made for #33 and despite my (and the top guys) best engineeering effort, the top still flaps in the breeze. The top was made well and fits tight as a glove. If I get over 30 miles an hour the top starts flapping on the edges. Last time out, I was really stepping on it and I managed to get a good vibration out of the the windshield. My question is, would the B&K windwings help with this issue? Does anyone know if you can run their mirrors and the windwings at the same time? I imagine that that is what they are for? I'm not crazy about the look but if it allows me to run my top and full speed at the same time, it may be my solution. Any help would be appreciated... Dave

Gene-C · Post by **Gene-C** » Wed Oct 26, 2005 10:58 am

Howdy Dave, I run B & K Wind Wings on my F1 with the top on and I don't find a lot of wind going through the buggy when I am at 70 plus miles an hour. You can run windwings and mirrors together. My top flaps a very small amount but does not go crazy (less then 1/2 inch at speed). I made my top ( and I make others for my buggy friends). The bows on my top are sewn into the top to add support and to keep flapping down. It also has adjustment straps that let the top "slide" into the fit so tenstion is tight all the time. Once you go witht he windwings you will find a lot of the air problem goes away and I for one would recomend B&K for any item they make, never had any trouble with the items. Hope this information helps - oh one more thing, I have friends down Texas way that have tops snapped into the roll bars and they even move around a little on the road. Neal Texas Manx club RBC meyer's Manx Club #1898 http://members.aol.com/texasmanxclub/im ... %20001.jpg

90volts · Post by **90volts** » Wed Oct 26, 2005 2:07 pm

dave, i didn't mention i think about the fabric straps that i have built into my top. they keep some tension on.they are from front to rear and one over passenger one over driver. they seem to help. mine flaps less with them than when i got it originally(he didn't add them first time.

Siggymanx33 · Post by **Siggymanx33** » Wed Oct 26, 2005 3:56 pm

The roof is as tight as it is going to get between the windshield and the roll bar. It actually pulled my windshied up about 1/8" from how tight it is pulling it. I plan on tightening up the windshield this winter. The top is extremlely tight fitting. It is just when I pick up speed it acts like a sail, it almost seems like it fits too tight. A boating friend sugested some thin plastic strips sewn in down the edges. Again, I would just like to know how much wind the windwings keep out? I can no longer imigine doing anything to the top that is going to help out as much as I need. Short of using a bow system or putting buttons or snaps onto the rollbar.

Lee · Post by **Lee** » Wed Oct 26, 2005 5:08 pm

Dave, I have been fighting with this issue for over a year now. The wind wings considerably cut down on the amount of air moving around in the cockpit, but it's hard to say if this would solve the problem. Most of the air comes from behind when you are at speed, and the interaction of the air moving over the top of the bimini top and the air billowing in from behind is what causes the flapping. The wind wings serve to keep the wind out of your face so you can breathe at 60+ MPH, but you still get that air from behind (even with a hard top and rear window installed). The wind actually curls around the windshield, the wind wings redirect where it comes back at you. Don't get me wrong, I installed my wind wings shortly after I got my Manx on the road, and I don't ever plan of removing them. The difference in comfort level is profound. My top has three straps that are sewn the entire length of the top. Each strap wraps around the roll bar and get cinched tight. There are also two straps that go down to the rear deck and get pulled tight. There is a snap on each side of the roll bar to keep the edges in place. Like you, I can pull my windshield back quite a bit during the process. It doesn't matter - the top still flaps a bit, especially in a headwind. I am limited to about 55 MPH if I want to keep the top from snapping. If I go faster it's hard to see out of the rear view mirror because the top is beating the windshield up so badly. The loud snapping sound also gets on your nerves after a while. In my case, the snapping is coming from the main part of the top. The edges are double thickness, so they don't move a whole lot. The main part is only one layer thick, so it snaps like a flag in the wind. Things might have been different if I had gone with the thicker top material. If most of the flapping you are experiencing is coming from the edges, adding the plastic strips should help a great deal. My solution is to have one more strap sewn in - this one will go around the connector tubes of the T top roll cage Rob has agreed to help me build. This should pull the center of the top down tight so it simply can't move. We also plan to attach the windshield to the front hoop, so it won't move at all when the top is tightened down. You really need more support in order to span the distance. A bow system or a roll cage seem like the only solutions. Sorry I couldn't be of more help.

Siggymanx33 · Post by **Siggymanx33** » Wed Oct 26, 2005 5:36 pm

Thanks for the replies...... I was really hoping that wind wings were the answer? Lee, you have it better than me, 40 mph is about all I can stand with the top. The material is really heavy duty too. Despite them being pretty expensive, I may have to give the wings a shot to see how much they help. The top is pretty well engineered. I do not have the straps running the length, but I do have a sewn in wrap around the roll bar, that gets wraped around roll bar padding, (for a little extra height). I also have tension straps around that and the edges to keep everything tight. Just not enough at speed though.

GotManx · Post by **GotManx** » Wed Oct 26, 2005 6:56 pm

I have never had a problem with my top flapping. I made it similar to a bimini top for a boat using hardware from a boat shop. The material used for the top is Sunbrella which should be available from most upholstry shops. The top is sewn around a 3/4" X 1/8" aluminum strap which slides into the windshield track and then the bows go though loops sewn in the top and it is tensioned by two staps to the rear bow.

Gene-C · Post by **Gene-C** » Wed Oct 26, 2005 9:16 pm

I would like to add somethiing here I did not mention before. The top shown in the pictures from the last post are indeed correct about no flaping. There is a reason for this. 1. The top is well made with the bows sewn in 2. The top itself takes the pressure - there does not seem to be any straps going through the top, they are connected to the last bow and not the top material which will not pull the material, the bow pulls the material. 3. The most important fact is that there are no sides to the top. I call them surrey tops but that is just me. I have made several of those and they indeed do not flap. The reason for the flapping is that the air not only goes over the top but also goes around the sides of the top. When I was testing the Long Body Top I make I had the three bows installed with a surrey type top. The sides tend to pull out at speed and that distorts the shape, thus flapping. 4. Wind does come through the back of the buggy when at speed but I solved that with a clear wind screen designed to fit the roll bar and it stopped that. Porsche has something like that in their convertables just for that reason. I will say that I have three tops for my buggy depending on what I want it to do. I have a surey, a bimini, and a two way top which converts to a full convertable as well as a binimi. Of course I want to say that these comints are based intirely on my own homemade test - I am not an engineer, just a guy who got tired of getting wet. :rock:

shaihulud · Post by **shaihulud** » Wed Oct 26, 2005 11:13 pm

I found that when I fitted a single bow, that goes across the top above the occupants heads, and which is hinged to the roll bar about 1/3 of the way down from the top, and the bow was tensioned up after fitting the top, with two straps rearwards to the roll bar, that the flapping stopped. By lifting the top up like the top of an aeroplane wing, it acts as an aerofoil. It has no tendency to flap as it wants to lift all of the time. If the edges of the bimini top flap, they could be tensioned up with some bungee cord, sewn into the hem.