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running on 13's
aka Keith - 8/10/11 at 10:15 AM

If is not one this it is another..

Picked up my new 13 wheels today minilight style and went to fit them , and they seem to hit on the brake calipers. Well clear of the handbrake spring.

the wheels have a lower offset, so shoud in theory sit further away frmo teh hub, and the brakes, but they seem to hit. is it spacer time, am i doing something wrong or is it get another type of wheel.

Cheers
Craig


coozer - 8/10/11 at 10:30 AM

Same problem here, new 13's clouted the shocker, fouled the handbrake cable.
Some reworking of the cable position, turning the shock, dismantling the hub for longer studs and spacers... nightmare!


aka Keith - 8/10/11 at 10:51 AM

That's what I don't get coozer. going frmo a 7 with et37 to a 6 with et23 I would have thought that my wheel face would have been further away from the hum, and it is, yet the wheel is binding on the caliper body.

Is there a work around on this?


coozer - 8/10/11 at 11:30 AM

Dunno mate, my problem was going from 15" diameter to 13.

Sure someone will be along to help soon. Any pics of the offending collision??


steve m - 8/10/11 at 12:02 PM

Could you stick a thin (10mm?) spacer to bring the wheels out slightley?

otherwise, sell the new wheels to me!!


daniel mason - 8/10/11 at 12:14 PM

A lot of 13" wheels don't clear due to the design of the wheel. I think td pro race 1.2, compomotive cxr and obviously caterham r500 wheels seem very popular and am sure flack monkey on here commented that the cxr's give the most clearance!
My r500 wheels fit perfectly with the shortened caliper spring


fullpint - 8/10/11 at 06:23 PM

You really need to see the caliper radial profile to ensure it fits with in the inside diameter profile of the wheel. Try making a cardboard template to produces the inner profile of the wheel and the place this on the hub of the car to see exactly whats hitting..
Those ET you quoted tells me that the out board flange will be in the same position for both 7" and 6". I'm guess your caliper hits the inner rim about half way down the rim profile which is where the outside diamter is a lot less than that of a 15" wheel. I presume a disc with a greater off-set would cure your problem? Therefore moving the caliper away from the mounting face of the wheel? As your disc one piece cast design?


aka Keith - 9/10/11 at 08:28 AM

Fullprint, I think I understood most of your post.

It is the shape of the inside of the rim, that is causing the issue. The Wheel is hitting the capiler casting at the sliders area. (I have put a illustratvie image in my photo archive)

I do not want to put a spacer on the back, as then I would probably have to get wider rear arches.

I am a bit confused by

" presume a disc with a greater off-set would cure your problem? Therefore moving the caliper away from the mounting face of the wheel? As your disc one piece cast design?"

Do you mean disc or do you mean wheel?
can you move the caliper?
Disc is solid sierra - so I assume it is a one piece cast design

Cheers
Craig


Wadders - 9/10/11 at 10:09 AM

Is the wheel fouling the brake caliper by much, its sometimes possible to grind a bit off the caliper to gain clearance, there is usually plenty of meat on them.

Al


aka Keith - 9/10/11 at 10:10 AM

Wadders, it is not by much, but then how much can I take off the caliper?


Wadders - 9/10/11 at 10:27 AM

Bit hard to comment without seeing where the problem area is, and just how much you need to remove, but a bit of judicial angry grinding is unlikely to weaken a sierra caliper, which is way over engineered for such a lightweight car....... can you post some detailed pics ?

just seen your other post, seems a bit extreme offloading the wheels at this stage, surely a solution can be found..... IIRC the clearance on mine is only a couple of mm, you don't need loads.

Al.




Originally posted by aka Keith
Wadders, it is not by much, but then how much can I take off the caliper?



gingerprince - 9/10/11 at 11:50 AM

Be careful with grinding the calipers - I didn't think I needed to take much off, ended up taking off too much and scrapping them!

http://www.locostbuilders.co.uk/viewthread.php?tid=141772


fullpint - 9/10/11 at 03:32 PM

Have you got access to a machine shop? Depending upon how much extra clearance you need you may be able to gain a few mm from machining the back face of the disc? As in where it goes over the hub axle followed by machining the same amount from the caliper mounting point. That way the relationship between the centre-line of the disc and the caliper remains the same dimension.


matt_gsxr - 9/10/11 at 04:34 PM

The 13inch wheels problem is pretty common with Sierra rear brakes.

One solution is to change the disks to Escort or Fiesta front disks (can't remember which year, but not recent!).

These have the two-fold advantage of more dish and smaller diameter.

You would need to remount the callipers, but you can then fit the wheels.

Not expensive to do, but a fair bit of effort.


aka Keith - 9/10/11 at 05:52 PM

unfortunately, fullprint, I dod not know of a good local machine shop


Matt, that is an option, lets just double check that I understand it. you put a smaller diameter disc on the back..so then how do you move the caliper to suit. the mounting holes in the rear uprights are fixed...are they not?

Cheers
Craig


fullpint - 9/10/11 at 06:12 PM

Sounds like you need a visit to a machine shop mate. I think Craig is saying the calipers will need re-mounting which could involve a plate being made up. Having worked for a wheel company for 27 odd years (previous job) it easy for me to recommend re-machining of parts. I was thinking about looking at going to 13's but I would try before I buy..
Can you not try taking the pads out (this may allow you to have movement in the caliper) and with the caliper un-bolted try and see how much clearance is needed? May be worth having an extra pair of hands to help hold/rotate bits 'n' bob's.