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I popped over to Jap4Performance my local Tyga suppliers website for an Ohlins Fork tool, trouble was the postage was on the salty side for what I was ordering, so I thought I'd make the most of the box by adding a pair of Brembo brake hangers to the order. I decided on black for the front and silver for the rear to match the stock fork lowers and the swingarm I'm running.



All that I needed was a pair of 84mm Brembo brake calipers. Doing a little research I had a couple of options as these calipers are rear OEM fitment on a number of bikes made by Ducati, Aprilia, and Yamaha even. The trouble is if I buy secondhand by the time I factor in a rebuild kit and effort I'd might have well bought new. So I started looking at new. Turns out you can get some trick CNC billet calipers, tempting, but way out of budget. Thankfully I found a supplier on eBay who checked out as a Brembo dealer (avoid suspiciously cheap Brembo's from Asia) from Italy and an order was placed when eBay were running a 15% site wide discount.



A couple of weeks later a pair of Brembo P2 34 calipers turned up. But they were damaged. It looked like they hit the floor or an end mill with some force. The supplier offered me the choice of a discount, or return for refund or replacement. I opted for replacement as I only wanted what I ordered and so a little fun started regarding the return postage, once eBay were involved everything was settled at no extra cost to me and the calipers went back and were replaced with a fresh pair.



I then thought I'd better just check something, the banjo bolt size. The Grom runs a M10x1.25 and the Brembo caliper takes a M10x1.0. So off to HEL Performance for a couple of banjos. And with that it was a simple case of drilling out the front master cylinder cover screw. Turns out Honda makes the screw head out of cheese, even when using the correct JIS screw driver.



All that was left was the simple job of removing the old calipers, adding the brackets, the new calipers, and then bleeding them. It was at this point I hit the next problem. Hose length and connector angle. I could have got away with reusing the front but it looked a little tight, the rear was too short though I could probably have made it work but it wouldn't have been pretty. Trouble is I was running a set of HEL lines, thankfully HEL do custom lines.



Back to HEL I went and ordered a pair of custom lines. The rear I ordered was a 60cm line with one straight fitting and one 45 degree side bend for the caliper end, and the front was a 82cm line with a 20 degree lift for the master cylinder side and a straight banjo connector at the caliper. I also added a rubber grommet and a bobbin grommet for the mounts. Now the OEM and HEL stock replacements have an additional bobbin grommet for mounting but the custom line only offers the two support options, so I used the bobbin at the mudguard and just a small P Clip at the lower yoke mount where the other bobbin was.



Now the final thing I ordered was some caliper bolts. The Tyga brackets came with some stainless M8x20 cap heads, the problem here was I was already running Titanium bolts on the front so over to Race Fasteners I went to order 4 replacement Ti bolts as, well, you know.



All that was left to do was to bleed the system, the front went fine, but the rear wasn't getting much pressure at the leaver. I'll be honest running the HRC reservoir doesn't make this an easy job as I use an air fed hydraulic bleeder that can burn through the fluid in the reservoir almost as fast as I can load it, but it wasn't that which was causing the issue, it was the placement of the bleed nipple. I was actually a little surprised I didn't get this at the front as the issue is similar, basically you need the nipple to be at the highest point in the caliper in order to expel the air as it rises above the fluid. The rear calipers nipple based on where the caliper hangs is a little on the low side. So I solved that by using a spanner to keep the pads apart as well as providing a hooking point to suspend the caliper off of the hanger from the rear indicator using a ratchet strap tied to the paddock stand, I really should have got a picture of that. The rear was now easy to bleed.



The conversion is now complete, all I need to do is to test ride it, but the weather isn't great and I'm suffering from a case of the plague so it might be a few more days before I test it out, but I'm happy with how it all looks. The only thing that I'm not so hot on is the cost, the rear bracket was a fair bit more then the front and that's understandable, but when you consider I don't actually use the rear brake at all and its only there for the MOT...
 

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With those calipers you can switch the bleed nipple and brake line placement without issue. With that underslung caliper you don't much of a choice but to remove the caliper and do it the way you did. The front can be done much easier by flipping the line and bleed nipple.

 

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Didn't know you could swap the bleed nipple and the hose point, seams a brilliant and obvious design feature now you mention it! I might just do that, might be able to reuse the old line as well as I think the front was actually a bit long as opposed to short. Thanks.
 

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Wow, good tip DIY01, that would've saved me a lot of time a few months ago.

I love my Brembo 4 pot and radial master...amazing feel and stopping power.
 
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