Help w/ soft top drumming - Defender Source
Defender Source  

Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions


Reply
 
Thread Tools
  #1  
Old September 21st, 2004, 12:12 PM
Seanh
Status: Offline
Sean Hanagan
94 D90 ST #910 Matilda
Member
 
Join Date: Dec 2003
Location: Edwards, Colorado
Posts: 179
Help w/ soft top drumming

I have a Badger/ RN top that drums like Micky Hart on speed. The worst configuration is when the top is on and the side and rear windows are out. The question I have is what about disturbing the flow of air over the top (Bernoulli)with lamps or a rack? Any first hand experience out there?
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old September 21st, 2004, 12:22 PM
Mike Hippert's Avatar
Mike Hippert
Status: Offline
D-90Slut/Stalker,SNLPres
94 D-90 Grinding Rover
Member
 
Join Date: Sep 2003
Location: Manchester NH USA
Posts: 4,789
Lamps make a bit of noise themselves. Oddly enough Yousef and I found a way to quiet down the top. When we loaded our stuff on top of his 90 it pushed down on the top and stretched the top a bit, after doing that there was no flapping.

On another note, do you have rollbar pads? The Velcro ones? They help a little.
__________________
Don't forget to
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
first then ask questions later! The loose nut behind the wheel
Reply With Quote
  #3  
Old September 21st, 2004, 12:40 PM
paulb's Avatar
paulb
Status: Offline
Paul / Boultbee
1994 D-90, Green #1576
Member
 
Join Date: Sep 2003
Location: Los Altos Hills California USA
Posts: 787
I gave up driving at speeds over 60 with the side and rear windows out. It got so bad that the drumming pulled out a rivet on the rail system at the rear left corner. The side window seem to be the problem so I put them in when traveling at speeed. The rear window I unzip and clip to the alpine bar to keep it out of the way. In my humble opinion, and not wanting to second guess or insult LR, the top attachment systems, either rail or snap can not handle the wind flow at speed.

The velcro rollbar pads DO help. And on Bernoulli, I believe the principle is that a when airflow is introduced to a disruptive shape (as in a wing) air is divided unequally into two flows. One is above and one below the object. If the flow below is smaller that that above, a pressure displacement occures allowing for lift (or in the reverse down pressure). Looking at the wind screen angle, ridge wher the top meets the front edge, the 3 humps in the top of my soft top to the rear, I venture to state (at my own peril) the aerodynamics of a D-90, at best, suck - literally - , and at worst, were just not engineered into the design.

Final comment. You are pretty close to CA or those warmer states. Ever concidered wintering there?
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old September 21st, 2004, 05:56 PM
Seanh
Status: Offline
Sean Hanagan
94 D90 ST #910 Matilda
Member
 
Join Date: Dec 2003
Location: Edwards, Colorado
Posts: 179
Mike,
The velcro pads you refer to go where on the truck. I did make some fleece covers for the diagonal roll cage supports to quiet the window flapping. The top you streched, was it a bestop or a canvas top (RN or Badger)? Mine goes right back into a firm shape.

Paul,
If I winter in CA then I cant ski! With regard to bernoulli I was thinking that since the faster the air moved across the top the lower the air pressure relative to the air inside the truck. If I could slow the air down over the top then the top would not be pushed up as much.
Reply With Quote
  #5  
Old September 21st, 2004, 08:29 PM
ronward's Avatar
ronward
Status: Offline
Redsrover
None - sadly
Member
 
Join Date: Oct 2003
Location: Columbus, Georgia, USA
Posts: 387
With the soft top windows in and zipped, open the drivers side door window about 2 inches by sliding the forward glass reward. Works like a charm on my 90.
Reply With Quote
  #6  
Old September 22nd, 2004, 08:11 AM
Mike Hippert's Avatar
Mike Hippert
Status: Offline
D-90Slut/Stalker,SNLPres
94 D-90 Grinding Rover
Member
 
Join Date: Sep 2003
Location: Manchester NH USA
Posts: 4,789
The pads go on the vertical supports of the cage. The top that we stretched was a Bestop.
__________________
Don't forget to
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
first then ask questions later! The loose nut behind the wheel
Reply With Quote
  #7  
Old September 22nd, 2004, 07:17 PM
Mark M
Status: Offline
Mark Mathews
'94 Beluga Black ST
Member
 
Join Date: Jun 2004
Location: West Hollywood, CA USA
Posts: 155
Sean, We have great skiing here in California. Mammoth Mountain and Lake Tahoe come to mind. Here in So. Cal there are a couple of slopes within a few hours of Los Angeles. Kind of neat... surf in the morning and ski in the afternoon.
Reply With Quote
  #8  
Old September 23rd, 2004, 03:00 PM
Seanh
Status: Offline
Sean Hanagan
94 D90 ST #910 Matilda
Member
 
Join Date: Dec 2003
Location: Edwards, Colorado
Posts: 179
Trade Western 3% powder for Sierra cement? Kidding, the back country skiing in CA is great and so is the cycling. At this point I'm only an hour away from great resort skiing and just a few minutes away from great bc runs. It's been snowing the last two days and I've had all the windown in which makes a huge difference.
Reply With Quote
  #9  
Old September 23rd, 2004, 05:22 PM
jstrong98's Avatar
jstrong98
Status: Offline
Jon Strong
Member
 
Join Date: Mar 2004
Location: Pennsville NJ USA
Posts: 98
I second the "open the window" method.

works like a charm for me.
Reply With Quote
  #10  
Old September 27th, 2004, 06:44 PM
Seanh
Status: Offline
Sean Hanagan
94 D90 ST #910 Matilda
Member
 
Join Date: Dec 2003
Location: Edwards, Colorado
Posts: 179
I live at 9000ft above sea level and the air gets quite chilly up here durring our 9 month winter.
Reply With Quote
Reply

Lower Navigation
Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Tags
soft top

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
1997 Bestop Soft Top Like New & Misc Parts Adam Armendariz For Sale - Parts 16 December 8th, 2005 01:43 AM
Best Top Soft Top For Sale WCURoverD90 For Sale - Parts 2 November 1st, 2005 04:24 PM
White 95 D90 Soft top for sale.. sniff.. Richard Dekkard For Sale - Vehicles 5 December 1st, 2004 12:38 PM
Original Soft Top 94 D-90 & Surrey Top!!!! doozle For Sale - Parts 7 November 10th, 2004 08:22 PM
Which is the best soft top for D-90? bbandit Defender Technical Discussions 13 March 9th, 2004 08:40 PM


All times are GMT -5. The time now is 03:20 AM.


Copyright