Goldline Caliper Pinch bolts - torque setting?

[ducatiz]

Fire.  not always good for the finish.

Pick up a couple of soldering guns.  The bigger ones with the two-part electrode.  remove the electrode and connect 8ga wire to each electrode and then to the ends of the bolt.  the bolt heats up because it is alloy steel and transfers the current well.  it heats up and the caliper stays mostly cool.

don't ask me how many times i've done it and wished i was more careful tho.

[Raux]

i was thinking more chemical-specific color coding, i don't know why "lavendar" came out.  wife is looking at colors to paint the bathroom, go figure. 

I've been working on a satellite transmission unit and it has two different colors for the o-rings on the transmission boom. green for non-conductive, black for conductive (or vice versa, don't have the spec sheet in front of me). but the point is, colors may definitely have some meaning.

[junior varsity]

Fire.  not always good for the finish.

Pick up a couple of soldering guns.  The bigger ones with the two-part electrode.  remove the electrode and connect 8ga wire to each electrode and then to the ends of the bolt.  the bolt heats up because it is alloy steel and transfers the current well.  it heats up and the caliper stays mostly cool.

don't ask me how many times i've done it and wished i was more careful tho.

i used type 2 child-safe fire.

on a serious note, i've blow torched (butane, on low) a pair of goldlines before to warm around the pinch bolts - these calipers were originally equipped on the m900 i just picked up for my wife to piddle around on - i knew they were going to be junk and wanted to know what was on the innards, because when i went to flush them with fresh brake fluid, mud-colored 'stuff' came out. (the brake lines were new so it wasn't them...)


i don't know much about disassembling a soldering iron or its electrodes, so i'd have to skip over that one. unless you can youtube a how-to, lest i end up with neat scorch marks on my hands.

[Cloner]

I don't know much about anodizing brake calipers, AM, but I can't see where either color anodizing or hard anodizing would present a problem as long as the appropriate seal glands, oil passages, and bores are properly masked.  I've seen tons of powder coated units, though, so I know that can be done.

I'm pretty sure the OE seals in the caliper are EPDM, as nitrile rubber is unsuitable for dynamic sealing in any type of brake fluid.  I could see Brembo MAYBE skimping on the o-ring between caliper halves, as that is a static joint (though nitrile rubber is still unsuited to that task, too), but they certainly wouldn't skimp on the dynamic (moving) joints due to the liability issues involved.

Taking out the cheese-headed bolts is easy.  Get a drill the same size as the bolt (8mm), then drill through the head, making sure the drill is well centered.....a task aided by the fact that the hex is centered... and when you get past it the head will fall off if the bit was well centered.  If not, you may have to use an 8.5mm bit to finish off the missed material to remove the head.  Once all bolts or bolt heads are removed, disassemble the caliper then remove the remainder of the bolt(s) with vice grips.  Easy!!  No heat required.  

Whilst we're talking about brakes, I'm currently working on a 1098s with monoblock calipers.  The right caliper has a double banjo bolt that hits the wheel and prevents removal of the caliper unless the pistons are fully retracted....and that's with worn pads.  I need to install new pads and I wondered if anyone has a "trick" that will allow me to avoid removing that double banjo bolt and what I believe will be a pain in the ass bleeding job (since the banjo is a high point in the caliper area)?

Anybody got a cool trick I might borrow?!?  Please!!  

[junior varsity]

Hmm... I may have a tip for you this afternoon - I'm going to run down to AMS to pick up a bucket of crushwashers as I have run out and want to plan ahead for reassembly day. I will ask Jordan what he does to work around this.

(you could ditch those 330s in favor of 320 )

[Speeddog]

How about removing the pads on that caliper?

~~~SNIP~~~

Whilst we're talking about brakes, I'm currently working on a 1098s with monoblock calipers.  The right caliper has a double banjo bolt that hits the wheel and prevents removal of the caliper unless the pistons are fully retracted....and that's with worn pads.  I need to install new pads and I wondered if anyone has a "trick" that will allow me to avoid removing that double banjo bolt and what I believe will be a pain in the ass bleeding job (since the banjo is a high point in the caliper area)?

Anybody got a cool trick I might borrow?!?  Please!!  

[Cloner]

How about removing the pads on that caliper?

I'm not sure there's room....but I'll try that.  Thanks, 'Dog.

[junior varsity]

Rebuild kits came in today from yoyodyne. Contrary to what Fred said, there is no o ring to connect the halves. Not cool that he said the kits did have em... and then they were absent.

[ducatiz]

Wrong said Fred

[battlecry]

I hate it when that happens.   

[junior varsity]

I was still planning on getting the EPDM o-rings... but it would have been really nice to have some authentic Brembo o-rings to have as spares, and more importantly - I was half intending on sending at least one of them to QTM Inc or the o-ring specific manufacturers listed earlier in this thread to make sure I get correct sized rings.

Also would have been nice to verify that the one I have in "good condition" is still the same size as it came originally - not shrunken or expanded from being immersed in brake fluid over the years... I don't think measuring O-rings is as trivial as measuring fork diameters - O-rings flex and squish and such. It appears to be the #10 size, but it would be nice to make sure, ya feel me?

The other thing that kind of plucks the short and curlies, is that these kits are not inexpensive. The 30/34 Piston/Seal kit for 4 Piston GP Caliper Brembo (120.2799.50) is $48.70 per caliper. I certainly don't mind replacing the pressure seals (even if those seals didn't leak) or even pistons (even though they showed no pitting at all), but the one thing I wanted isn't a part of the kit.

And really, Brembo, if you are going to make an overhaul kit, include the damn center O-ring and new steel bolts for that price.  I also grabbed the pin/clip kits ($9.15/ea) - but again, if you are doing an overhaul, you ought to replace the pin that the pads slide on so there's no stiction there either - should be included with the kit (and available separately for non overhaul replacements).

The quote from QTMI was "about $50" and included "the middle O-ring and the 4 dust seals which aren't used on the GP 30/34s, just the goldlines". Well hell, I went with Fred at yoyodyne since he's supposed to be the go-to guy, but I would give these folks a shot next time too. (Didn't help that Fred didn't want to give me a price on the Ti rear axle for the 851/888/M shown on their website).   Good news related to axle though, my rear axle (and a spare 20mm front axle with threaded bush for fork lower, and DSS swingarm pivot) are off to TPO for some measurements. Perhaps others would be interested in lighter alternatives as well (I know that my axles are starting to look a little ragged from repeated installation and removal over the years - it is more than 10 years old, and many of the parts go back even further!)

[junior varsity]

Oh, and local guy does Cerakote. I think I'm going to meet with him to see about doing the calipers - his quote was really good.  Yay for combining the resources of the gun and moto communities

[junior varsity]

So.... quick update - the go-to people for o-rings, as far as customer service and helpfulness has been Marco Rubber.

I had a set of samples sent to me for the o-ring that is not included in the 30/34 kits. First try was "so very close" but not quite the cigar. The key specifications are the OD (10mm) and the thickness (somewhere between 1.5mm and 2.0mm), rather than the normal specification of ID and thickness.

The OD was spot on (10mm), and the thickness was "very close" but at 1.5mm, I was able to compare with the good original I had, and two new ones I got in brembo rebuild kits for other calipers.  Not sure there would have been enough "squish" for a good seal with just 1.5mm of thickness and my calipers are too crude to correctly size the O-rings I have.

So I contacted Marco Rubber again about sending in what I had - and that was totally acceptable, so I boxed up one used and one new (used: so they could see the amount of squish that was permanent in what I got, and new: for what it started as).   Filled out form with detailed information about operating conditions and off they went.

They'll be getting them in and contacting me about making the 'exact' right ones out of EPDM and/or AFLAS and any other suggested materials - and possibly in other shapes such as box-cross section and x-type - so the "best" seal can be had.   And when they have it all figured out and ready to go for me, I told them I'd be buying at least 20-50, and would consider buying more like 500-1000 (price depending) so I could have enough others for anyone else who wants these.   Alternatively, I may be able to get a "part no." from them, so a person could order direct from them.  Hopefully in short time we will see.

Out of curiosity, I also boxed up and sent off one of each size piston (30mm and 34mm) and a bunch of the 'old' seals from the caliper to see if they had any thoughts on improvements for these knowing the operating conditions, like fluid, temp, seal type, and with a focus on maintaining the necessary pressure seal while also providing good piston retraction, and be tough enough to operate in the calipers that do not have dust seals.    Told them if they didn't want to mess with those, no big deal, but didn't hurt to include them while I was already sending some on their way.