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Help - rear brakes dont fit!!!
bpgoa - 9/10/07 at 10:13 PM

Time to turn to the forum for some help!!!

I've just fitted the rear drum to disk conversion from Rally design.... and this is the result..

don't fit one
don't fit one


The arrow points to where the pipe attaches.... it's fouling the de-dion and it's not even straight (parallel to the disk)...

The holes on the hub carrier are asymmetric so you could only rotate the mounting through 180 degrees...

and the hole for the the brake hose is tight against the hub carrier so 90 degrees don't work (it comes with banjo fittings.

it would have to be a hole or come in through the bleed nipple and that means no bleeding of the brakes.. Help

I'm sure the pipe isn't going to attach and even if I cut a hole in the tube it's going to be tight (would that be safe?)

Anyone else had this problem?

Anyone got a work around?

Or do I have to send them back to Rally Design and get the pimping 4 pots (overkill!!)

This is the view with the caliper off


dont fit 2
dont fit 2


oh yeah... that's one of John Roberts de-dions


Any help appreciated...


A.

[Edited on 9/10/07 by bpgoa]

[Edited on 9/10/07 by bpgoa]


oadamo - 9/10/07 at 10:24 PM

didnt see that bit about the pipe pmsl.
adam

[Edited on 9/10/07 by oadamo]


blakep82 - 9/10/07 at 10:30 PM

would banjo fittings allow the hose to come out horizonally?


RazMan - 9/10/07 at 10:34 PM

I'm not familiar with the conversion but can you rotate the caliper bracket 90 degrees and mount the caliper in front of the hub rather than on top?


russbost - 9/10/07 at 10:34 PM

Looking at how beefy that axle housing is I can't imagine that cutting a small hole would significantly affect it's strength. What exactly is the problem with the pipe attachment & would a cranked end on the fllexy pipe help? I can do braided flexies with anything up to a 90degree crank if that helps at all - see my archive for pics of sample hoses (none of the 90 deg cranked unfortunately).

[Edited on 9/10/07 by russbost]


Ketchup - 9/10/07 at 10:58 PM

i recon that the plate needs moving 90 deg as raz said, so the caliper is leading instead of being on top, it looks odd fitted where it is


bpgoa - 9/10/07 at 11:06 PM

The holes on the hub carrier are asymmetric so you could only rotate the mounting through 180 degrees...

and the hole for the the brake hose is tight against the hub carrier so no joy there. it would have to be a hole or come in through the bleed nipple and that means no bleeding of the brakes.. Help


Has anyone fitted the 4 pot kit... would that help?

[Edited on 9/10/07 by bpgoa]


BenB - 10/10/07 at 09:10 AM

That doesn't look right!!

How is the brake disc attached? I can't see how with the set-up the disc will sit in the groove in the caliper!!!! Unless I'm being dim this morning that's more of a problem than the brake fluid pipe clashing with the uberhuge axle tube!!!


RazMan - 10/10/07 at 09:42 AM

I have to say that it doesn't look quite right.
Here's a pic of my Sierra setup from a similar angle and your caliper seems too far back - maybe some spacers are missing?

[Edited on 10-10-07 by RazMan] Rescued attachment Rear Hub.jpg
Rescued attachment Rear Hub.jpg


tks - 10/10/07 at 09:45 AM

first thing i would do is get a rear disk over there and measure up the offset.

Is this the poss of the caliper??

then i would just drill an 20mm hole in that UBER big tube to allow for the banjobolt/hose

that tube is well over engineered if you ask me.

i reckon tha tif that tube is round overall turning around the bracket isn't the solution

maybe on rear druk the hub is turned 90degrees..??

Tks

[Edited on 10/10/07 by tks]


TimC - 10/10/07 at 09:55 AM

As Raz says I think the offset 'looks' (can be deceiving) wrong!?


blue2cv - 10/10/07 at 07:23 PM

Perhaps the bracket is the wrong way round, obvious way to check is offer up disc first


britishtrident - 11/10/07 at 12:10 PM

I think you really have to sit down for a sanity check here.
The facts are
The De dion looks over engineered in terms of thickness and sizes.
The calipers won't fit the de dion as it is.

Some of the options are

(1) Major surgery to the de dion -- it won't be elegant but it is so heavily over speced it won't cause stiffness or strength problems.
(2) Fit drum brakes.
(3) Try different calipers
(4) Fit a different De Dion
(5) Fit a live axle ---- might actually be the best option.


britishtrident - 11/10/07 at 12:28 PM

Remove metal here Rescued attachment dont fit 2.jpg
Rescued attachment dont fit 2.jpg


britishtrident - 11/10/07 at 12:30 PM

Like this


[Edited on 11/10/07 by britishtrident] Rescued attachment dont fit 1.jpg
Rescued attachment dont fit 1.jpg


Syd Bridge - 11/10/07 at 01:24 PM

I don't think I'd take out quite that much!!!

A small notch to accommodate a 90degree bend wouln't hurt though.

Cheers,
SYd.

[Edited on 11/10/07 by Syd Bridge]


ettore bugatti - 11/10/07 at 06:57 PM

Didn't you punt the lefthand part (caliper bracket) on the right side and vice versa?

If you change them it looks to me that the caliper moves too the outside.


britishtrident - 11/10/07 at 07:02 PM

quote:
Originally posted by Syd Bridge
I don't think I'd take out quite that much!!!

A small notch to accommodate a 90degree bend wouln't hurt though.

Cheers,
SYd.

[Edited on 11/10/07 by Syd Bridge]


Most the material to be removed is carrying zero load, an FEM would run would show that.
Also the material thickness of assembly is so thick it gives a massive safety factor.


britishtrident - 11/10/07 at 07:04 PM

quote:
Originally posted by ettore bugatti
Didn't you punt the lefthand part (caliper bracket) on the right side and vice versa?

If you change them it looks to me that the caliper moves too the outside.


Well spotted that should help


bpgoa - 11/10/07 at 09:40 PM

I've tried the disks and they are lined up ... no probs..

the de dion is designed to take both push in and bolt on carriers hence the big tube...

and although it looks quite chunky it's not that bad weight wise...


I've had an email off John - the maker of the de dion... and I'm going to post it here ...

There is a tendency to whinge in these forums but not necessarily give out praise where it's deserved... if all part suppliers and kit manufacturers took a leaf out of Johns book it would be a lot better place....


please read.......




Hi Adrian,

Seen the post on locostbuilders about the brakes not fitting.

Obviously when designing things there is always a comprimise, and while we try a number of set ups we don't try everything. I'm not familiar with the Rally design set up so I'm keen to see where modifications need to be made.

Firstly, the design of the de-dion is so that CV jointed axles can be used (two types of CV available, Ø108mm and Ø100mm), a 5" tube is the only option, The new Haynes Roadster uses this size as well, so this conversion isn't going to fit these either. As we are now heavily involved with Haynes Roadster parts I am keen to see what can be done.

Is it just the inlet point that doesn't clear?

If you want me to carry out the modifications I'll organise a courier to pick up all the parts and ship them here and return them to you when done.

Let me know if you want to do this, it'll only take a week.

Kind regards

John.



What do I say to that except - Thanks John.


I contacted Rally Design, and they connected to the forum to look at my predicament... And they have offered a refund if i can't get it to work... so Thanks to them also.



Now if everyone else who gets good service would care to post here... We'd know who the good guys were ... as well as the bad..


Oh Yeah... nearly forgot.... Thanks for all the replies and suggestions... I'll keep you posted.

[Edited on 11/10/07 by bpgoa]