lsdweb
|
| posted on 20/8/06 at 09:12 AM |
|
|
Caliper positioning
Hi All
I've had a bit of a problem in refitting my rear calipers onto the alloy uprights, as the thread has stripped in one of the caliper mounting
holes. I could drill, tap or try a helical insert but there's an easier option. The uprights are symmetrical so they have caliper mounts at the
front and rear and the mounting holes are OK on the rear mounts.
Can anybody see a problem in mounting the calipers at the rear of the upright instead of the front ? I'll swap the rear calipers over to ensure
the bleed nipple stays on top.
Alternatively, I could swap the rear uprights around but that's a bigger job!
Regards
Wyn
 
Rescued attachment IMG_0251.JPG
|
|
|
|
|
UncleFista
|
| posted on 20/8/06 at 09:36 AM |
|
|
Personally, I'd helicoil it 
Tony Bond / UncleFista
Love is like a snowmobile, speeding across the frozen tundra.
Which suddenly flips, pinning you underneath.
At night the ice-weasels come...
|
|
|
nib1980
|
| posted on 20/8/06 at 09:51 AM |
|
|
I'd suggest helicoil, but so long as it is common left to right you should be ok.
|
|
|
big_wasa
|
| posted on 20/8/06 at 09:56 AM |
|
|
I would helicoil it aswell.
|
|
|
MikeRJ
|
| posted on 20/8/06 at 10:03 AM |
|
|
Only problem I could see is if you have a handbrake built into the calipers as the cables will need a little bit of re-routing.
Personaly I would helicoil it, in fact I would be tempted to helicoil all of them if the caliper bolts are threaded straight into the alloy.
|
|
|
nitram38
|
| posted on 20/8/06 at 11:12 AM |
|
|
I moved my front calipers to the front of the discs instead of the rear of the disc like the donor, with no ill effects and the car passed sva this
way.
|
|
|
the_fbi
|
| posted on 20/8/06 at 11:58 AM |
|
|
This may be one of the most stupid things I've ever posted, but just in case its not....
If the caliper is on the leading edge of the hub, and you brake, does the rotating mass of the wheel push the tyre into the road?
If so, and the way my brain is currently thinking it through, it does, then the last place you'd want the caliper is on the trailing edge of the
hub, as when you brake the tyre is lifting off the surface and has a higher chance of locking.
It sounds strange seeing as the whole wheel assembly is being braked, but something is nagging me saying the above is true.....
So I'd keep it on the leading edge and helicoil or drill out and stick a bolt straight through (perhaps not possible).
|
|
|
lsdweb
|
| posted on 20/8/06 at 01:06 PM |
|
|
Thanks Guys
It looks like Helicoil is the answer! I've never done this before - it looks easy but I don't want to bu**er up my upright as I
don't have a spare and time is tight!
I've drilled the hole and tapped it for a 10mm X 1.5mm bolt but I'm not happy now I've had this problem. So, should I be buying a
10mm thread repair kit like
this
?
The original thread was 3/8" UNC and I'd like to do the other three calipers as well!
Regards
Wyn
|
|
|
big_wasa
|
| posted on 20/8/06 at 04:20 PM |
|
|
Easy to do, only recomendation is to make sure you drill and tap it square and not on the piss. Its easy done, guess how I know this 
I like them so much I do this to most alloy bits.
|
|
|
roadboy
|
| posted on 20/8/06 at 04:23 PM |
|
|
It is common for people to helicoil threaded pieces of aluminium even if it is not damaged, especially if it is to be stripped & rebuilt often as
the helicoil is stronger than the ali. Best bet Helicoil.
HTH
Ian
Jude Performance Services
|
|
|
lsdweb
|
| posted on 20/8/06 at 05:02 PM |
|
|
Thanks guys
Just ordered a 10mm kit from Frost Auto.
Regards
Wyn
|
|
|
lsdweb
|
| posted on 24/8/06 at 09:41 PM |
|
|
Success!
Helicoiled!
Great piece of kit - I should have bought one years ago!
Wyn
|
|
|
MikeRJ
|
| posted on 24/8/06 at 10:02 PM |
|
|
quote:
Originally posted by the_fbi
This may be one of the most stupid things I've ever posted, but just in case its not....
If the caliper is on the leading edge of the hub, and you brake, does the rotating mass of the wheel push the tyre into the road?
The answer is...no. Irrespective of the position of the caliper on the upright, it will exert the same torsional force upon the upright.
If the caliper were mounted on a completely separate structure to the upright (and not connected to the upright in any way) it would indeed try to
move the the suspension up or down depending on caliper position.
The only way that the tyre will be lifted from or pushed into the ground is via weight transfer, and this will not be influenced by the position of
the caliper (well, perhaps a very, very tiny amount due to moving the C of G with the caliper!).
Lsdweb, helicoils are wonderfull things, and can realy get you out of the sh*t! Normaly however you would keep the same thread, i.e. you drill/tap
out the hole with the same pitch thread but with a larger diameter and the helicoil brings the thread diameter back down to standard. Nothing wrong
with changing the thread though as long as the new diameter is large enough to remove all tracres of old thread.
|
|
|
lsdweb
|
| posted on 25/8/06 at 09:38 AM |
|
|
Thanks Mike
I would have liked to stay with the same size thread but there was no chance. The 10mm metric helicoil was the next size up - I'll do all the
other uprights over the winter as well.
Regards
Wyn
|
|
|
