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  #1  
Old 12th September 2010, 10:55 AM
HandyAndy's Avatar
HandyAndy HandyAndy is offline
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Default Brake pressure/ brake lights

I,m not sure which section to put this query into as it is related to brakes & Lights......

I have fully bled my brakes & to be honest very pleased & relieved that it was a "Pain free" task, got very good firm pedal pressure, no leaks etc.

BUT

I,ve rigged up some rear lights ( changing them as not happy with the way they look),
My question is, when I press the brake pedal the rear brake lights don,t come on as quickly as I thought they would or should, basically my brakes are working before the lights come on, If i just lightly apply my brakes the lights don,t appear to react unless I use more pressure on the pedal...as if I,m braking hard.

Any suggestions please?

cheers
andy
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Old 12th September 2010, 11:36 AM
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twinturbo twinturbo is offline
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Unscrew the sender whilst applying pressure to the pedal slightly so that fluid is expunged out the union ( a bit like leaving it off all together and letting lots of fluid pi55 all over the floor.)

then fit the sender whilst fluid is still being expunged, increase pedal preasure as you do so.


See if that helps.

TT
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  #3  
Old 12th September 2010, 11:37 AM
les g les g is offline
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easy one Andy
you can check your switch with a meter to see when or what pressure the lights are illuminating
if you want the lights to be instantaneous you will need to find a way of fitting a mechanical pedal switch
some of our plant is fitted with these hydraulic b/l switches and you have to give the the pedal a hefty shove to get the lights on
the ones with mechanical switches light faster
it takes quite a bit of hydrulic pressure to overcome the spring inside the switch
also it can help if you mount the switch upside down or on its side so no air is trapped in the switch
it can be the air compressing and not lifting the switch/spring thing
cheers les g

Last edited by les g : 12th September 2010 at 11:39 AM.
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Old 12th September 2010, 11:43 AM
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HandyAndy HandyAndy is offline
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Cheers TT, I,ll try that this afternoon ,

Les,
Yes, like you say it appears a hefty shove is required to make the pressure switch illuminate the brake lights
I would personally prefer that the lights more or less come on the moment I touch the pedal, I,ll have a go at what TT suggests & if that fails I,ll look at installing a mechanical switch on the brake pedal.......hmmm MORE electrical work

cheers guys.

Andy
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Old 12th September 2010, 01:43 PM
mr henderson mr henderson is offline
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I much prefer a mechanical brake switch, simple, reliable, easy to adjust, you can even set them up so that you can touch the pedal and make your brake lights come on without doing any actual braking which can be handy if you've got some idiot following too close, etc.
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Old 12th September 2010, 06:30 PM
flyerncle flyerncle is offline
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How far away from the cylinder is the switch,most electric switches have a fair amount of travel and take into account the servo adding to pedal travel and its no hassle wiring one up just swap wires one to the other.

Another thought,what circuit have you put it in as this will affect the pressure output, usual ratio of 60/40 front to rear in most cars,rear one should in theory give lower pressure.
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Last edited by flyerncle : 12th September 2010 at 06:33 PM.
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Old 12th September 2010, 06:59 PM
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Cheers Mr H, yes , I too would prefer the quicker reaction time of a mechanical switch, also like your suggestion of the oppurtunity to activate the brake lights without actually engaging the brakes

Flyerncle.....

My brake pressure switch is approx 4 inches from the M/C body, & its in the front pipe system as I thought along the lines that greater pressure would go to the front brakes.

I suppose I,ve been used to motorcycle brakes that has a tiny mechanical switch attached to the brake lever.

cheers
andy
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Old 12th September 2010, 10:18 PM
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David_17 David_17 is offline
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If you do want to try TT's method first, you're welcome to borrow my leg sometime to come and hold your pedal down whilst you do it. Won't be easy doing both at the same time by yourself

Let me know

Dave
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Old 12th September 2010, 10:21 PM
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Quote:
Originally Posted by David_17 View Post
If you do want to try TT's method first, you're welcome to borrow my leg sometime to come and hold your pedal down whilst you do it. Won't be easy doing both at the same time by yourself

Let me know

Dave
Cheers Dave, that would be a big help

I had visions of using a bottle jack on the pedal

Let me know when you are free.

cheers
andy
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Old 12th September 2010, 10:37 PM
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I've got 3 more days work this week, then i'm off for 2 weeks (as far as i know at the moment). Whenever you're ready, let me know.
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