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350TSS · 23-10-2018, 03:52 AM

Whilst waiting for the moulds to cure completely I thought I would have a go at the calipers.
I have never really been a fan of Brembo gold brake calipers, it does not appear to be quite the same colour as the anodised disc carrier centre and is some way off the colour of the gold anodising on the forks and definitely doesn’t match Ohlins gold and is different again from the gold of the standard frame.
I will go for a tasteful satin black but I am not sure whether to highlight the Brembo logo on the casting.
The rear caliper (my original M900 one) came apart relatively easily and cleaned up nicely. Oddly only one of the two bolts holding it together showed any sign of Loctite.
The front forks I am using are S4 (silver anodised, 25mm spindle and wider spacing caliper mounting bolts) so I had to buy second hand wider spacing calipers.
There are 4 x M8 x 40mm socket cap screws holding the caliper together. With the first front caliper I tried to split, it became obvious why these calipers were sold, two of the bolts were seized solid and the socket head on one bolt was mullered so badly even the next size torx bit was sloppy. I shall leave them overnight with penetrating oil doing its best, but I have the feeling that this will be an absolute sod to get apart. As someone once said “ as a motorcycle mechanic you are always only one broken (or seized) bolt away from a 3 day nightmare”. At that point I did not have the mental strength to look closely at the other front caliper.
My normal approach to this would be to resort to a 2lb lump hammer and / or an impact driver but there is no way to support the back of the caliper casting such that the force of the blow is directed through the bolt only and I am worried about damaging /distorting the caliper alloy casting. A second option is to apply my brazing torch flame to the internal hex on the socket screw and hope the differential expansion rate of steel and aluminium breaks the Loctite, but I still have no means of applying a turning force to the bolt head.
I have little confidence that an “ease-it-out” will work as the shape of the casting is such that it will be very difficult to drill the bolt parallel and concentric to the bolt shank. Also the largest I could use would be about 4 to 5mm and I could end up with a worse problem of a broken hardened steel “ease-it-out” stub sticking out of a still stuck fast bolt.
My current thinking is to find the largest size imperial (1/4”) allen key that will go into the socket head and cut about a 40mm length, (the “sacrificial” allen key). I already have some ½” square drive allen key holders where the allen hex bit is retained by a grub screw.
I will then MIG weld the sacrificial allen key into the offending bolt (the heat should help with breaking the Loctite), remove the good allen key from my holder and fit my sacrificial allen key into my empty ½” square drive holder and thence to my electric rattle gun. The more I think about the more I am confident this will work – tomorrow will tell.

23-10-2018, 03:52 AM	#778
350TSS Too much time on my hands member Join Date: Jan 2013 Location: Shipbourne Bike: M900 Posts: 1,419	Whilst waiting for the moulds to cure completely I thought I would have a go at the calipers. I have never really been a fan of Brembo gold brake calipers, it does not appear to be quite the same colour as the anodised disc carrier centre and is some way off the colour of the gold anodising on the forks and definitely doesn’t match Ohlins gold and is different again from the gold of the standard frame. I will go for a tasteful satin black but I am not sure whether to highlight the Brembo logo on the casting. The rear caliper (my original M900 one) came apart relatively easily and cleaned up nicely. Oddly only one of the two bolts holding it together showed any sign of Loctite. The front forks I am using are S4 (silver anodised, 25mm spindle and wider spacing caliper mounting bolts) so I had to buy second hand wider spacing calipers. There are 4 x M8 x 40mm socket cap screws holding the caliper together. With the first front caliper I tried to split, it became obvious why these calipers were sold, two of the bolts were seized solid and the socket head on one bolt was mullered so badly even the next size torx bit was sloppy. I shall leave them overnight with penetrating oil doing its best, but I have the feeling that this will be an absolute sod to get apart. As someone once said “ as a motorcycle mechanic you are always only one broken (or seized) bolt away from a 3 day nightmare”. At that point I did not have the mental strength to look closely at the other front caliper. My normal approach to this would be to resort to a 2lb lump hammer and / or an impact driver but there is no way to support the back of the caliper casting such that the force of the blow is directed through the bolt only and I am worried about damaging /distorting the caliper alloy casting. A second option is to apply my brazing torch flame to the internal hex on the socket screw and hope the differential expansion rate of steel and aluminium breaks the Loctite, but I still have no means of applying a turning force to the bolt head. I have little confidence that an “ease-it-out” will work as the shape of the casting is such that it will be very difficult to drill the bolt parallel and concentric to the bolt shank. Also the largest I could use would be about 4 to 5mm and I could end up with a worse problem of a broken hardened steel “ease-it-out” stub sticking out of a still stuck fast bolt. My current thinking is to find the largest size imperial (1/4”) allen key that will go into the socket head and cut about a 40mm length, (the “sacrificial” allen key). I already have some ½” square drive allen key holders where the allen hex bit is retained by a grub screw. I will then MIG weld the sacrificial allen key into the offending bolt (the heat should help with breaking the Loctite), remove the good allen key from my holder and fit my sacrificial allen key into my empty ½” square drive holder and thence to my electric rattle gun. The more I think about the more I am confident this will work – tomorrow will tell.