Haynes Forums  

Go Back   Haynes Forums > Haynes Roadster Forums > Chassis
FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 19th January 2013, 01:17 PM
DaveyB DaveyB is offline
Senior Member
 
Join Date: Mar 2008
Posts: 141
Default Roll bar height too

After roughly positioning my seats and mocking up position of roll bar my head seems close to the top of it too.Instead of butt welding same size bar to bottom to increase height I thought about boring some sleeves out of bdms bar making them same thickness and getting a good fit round the roll bar and welding on the inside and the outside to give me the extra height. And perhaps making the rb1 plates a bit thicker.
What are people's thoughts?

Thanks
Daveyb
Reply With Quote
  #2  
Old 20th January 2013, 12:04 PM
PorkChop PorkChop is offline
Senior Member
 
Join Date: Jul 2011
Posts: 394
Default

The yardstick I would use is 'would a MSA scrutineer pass it?'

The answer in this case would be a firm no. The roll bar is meant to protect your bonce if the worst happens. By extending it in any way, you're introducing 2 possible failure modes that simply don't need to be there.
Reply With Quote
  #3  
Old 20th January 2013, 08:05 PM
Davey's Avatar
Davey Davey is offline
Senior Member
 
Join Date: Dec 2009
Location: Telford
Posts: 1,040
Default

Quote:
Originally Posted by PorkChop View Post
The yardstick I would use is 'would a MSA scrutineer pass it?'

The answer in this case would be a firm no. The roll bar is meant to protect your bonce if the worst happens. By extending it in any way, you're introducing 2 possible failure modes that simply don't need to be there.
Fair point but an MSA scrute is unlikely to pass a roll bar that is not sufficiently above the head of the driver either . Draw a line from the top of roll bar to next structural point forwards, in this case the front frame of the chassis and there is a minimum clearance distance required by MSA/FIA, don't know the clearance off the top of my head (excuse the poor pun), but can look it up later if required.

D.
__________________
visit my website at www.cossie.davenewell.co.uk
Reply With Quote
  #4  
Old 20th January 2013, 09:25 PM
PorkChop PorkChop is offline
Senior Member
 
Join Date: Jul 2011
Posts: 394
Default

Then the answer would be to get a roll bar made up that meets your spec, like I'm doing. The book spec bar wouldn't pass MSA either (no diagonal for starters).
Reply With Quote
  #5  
Old 21st January 2013, 06:28 PM
DaveyB DaveyB is offline
Senior Member
 
Join Date: Mar 2008
Posts: 141
Default

Thanks for the response, great idea about using a piece of string to check out the distance ! I will certainly check that out. I tried using the self timer on the camera positioned straight ahead. Your method will be a lot more accurate. Knowing the actual distance may be helpful too.

Did not really want to have to go down the bespoke route, but looks like I may have to consider a bespoke bar after all, i purchased one through a group buy a while ago and did not even think there would be a problem !

Thanks again
Daveyb
Reply With Quote
  #6  
Old 21st January 2013, 06:31 PM
Tatey's Avatar
Tatey Tatey is offline
Senior Member
 
Join Date: May 2009
Location: Leicester
Posts: 827
Default

I'm 6'5" and had to get a taller roll bar made up, I think it had an extra 100 mm of height, this was to take into account that I'd be wearing a helmet and if I had to use the roll bar then I'd be upside down and hanging out of the harness.
__________________
1.8 Silvertop Zetec (ZX6R Carbs + Megajolt) + Type 9

My Build Blog: http://www.haynes.co.uk/forums/showthread.php?t=2736 - Last Update: 31st October 2020

Total Spent so far: Stopped counting
Reply With Quote
  #7  
Old 21st January 2013, 06:37 PM
DaveyB DaveyB is offline
Senior Member
 
Join Date: Mar 2008
Posts: 141
Default

From my rough calculations thats about how much extra I need to add.
Did you basically add 100mm on to the book roll bar example. And it still fits ok or did you have to change angles as well?

Daveyb
Reply With Quote
Reply


Thread Tools
Display Modes

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

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 03:15 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.