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Technical & Reference Section => Tech and Restoration => Topic started by: alltalk on June 24, 2008, 09:07 PM

Title: how to centre ad 990?
Post by: alltalk on June 24, 2008, 09:07 PM

Sorry for being dumb
can't find any info on how to centre these things
first time I've used u brakes - always used normal calipers before
they're 996 fiesta if it makes a difference
thought I had it cracked but now one side is always at the rim

cheers

Martin

Title: Re: how to centre ad 990?
Post by: TwoBobRob on June 24, 2008, 09:11 PM

It's all about the spring tension buddy   :)


All you need to do is hold the outer nut with a 13mm (i think) spanner, rotate it toward the tyre so it brings the pad off the rim. 1/8th to 1/4 turn is all you need. Hold that postion with the spanner, and lock off the centre bolt with the 5mm allen you're holding in your other hand   :LolLolLolLol:

Repeat for t'other side.  Be aware that the springs are different colours, as they are wound in opposite directions....

Hope that helps   :)

Title: Re: how to centre ad 990?
Post by: alltalk on June 24, 2008, 09:40 PM

thanks for that
I think I might not have loosened the allen bolt enough before I adjusted

I can't have been so stupid as get the springs mixed up ............ could I?
was messing with a few different sets when I built the bike......nah....couldn't be THAT stupid     :LolLolLolLol:

Title: Re: how to centre ad 990?
Post by: TwoBobRob on June 24, 2008, 09:46 PM

The centre bolt just needs to be cracked off, so that the adjuster nut can freely rotate.

As for mixing the springs up, yeah. It happens to all of us  :-[

I think  (my bikes in the garage and I can't be arsed to go and look),  as you look down on the brake the gold spring is the left spring.  I'm sure you'll see a pic elswhere in this section, AD setup has been discussed before.

By the way, if the springs are buckled out of shape  (due to overadjustment usually) then they're scrap really. You can get new ones from Billys.  :)

Title: Re: how to centre ad 990?
Post by: perry on June 24, 2008, 10:05 PM

go for as little spring tension as you can for a nicer feel at the lever

mates back in the day would crank them right round  ::) it was like a full on forearm workout

Title: Re: how to centre ad 990?
Post by: JT71 on June 25, 2008, 08:22 AM

yep just a quarter turn. I got advice on setting my Hombre up from twobob and he was spot on.  :daumenhoch:

Title: Re: how to centre ad 990?
Post by: alltalk on June 25, 2008, 10:42 AM

done it!
the spring was bent out of shape like you said - I had another though luckily
adjusted perfect

thank you very much for the help

Title: Re: how to centre ad 990?
Post by: subversion on June 25, 2008, 02:21 PM

Quote from: perry on June 24, 2008, 10:05 PM

it was like a full on forearm workout

Like when the wifes out? ;D

Title: Re: how to centre ad 990?
Post by: perry on June 25, 2008, 02:23 PM

exactly  ;)

Title: Re: how to centre ad 990?
Post by: pickle on June 25, 2008, 02:26 PM

aint got a clue what you two are on about  :angel:

Title: Re: how to centre ad 990?
Post by: perry on June 25, 2008, 02:30 PM

getting our spanners out and twisting some nuts  ;) ;D

i always put plenty of lube on the posts too  :)

Title: Re: how to centre ad 990?
Post by: TwoBobRob on June 25, 2008, 09:02 PM

Quote from: alltalk on June 25, 2008, 10:42 AM

done it!
the spring was bent out of shape like you said - I had another though luckily
adjusted perfect

thank you very much for the help

 ;) :daumenhoch: