Neutron Components Emergency Bleed Kit review – the holiday saver you never knew you needed

The latest tool from Neutron means you can now bleed your brakes anywhere, potentially saving your bikepacking epic or enduro week in the Alps

Neutron Components Emergency Bleed kit on bike handlebars
(Image: © Neal Hunt)

BikePerfect Verdict

Well-made, well-thought-out product with some neat features that might just save your next adventure. A niche tool for sure, but one I would certainly take with me on my next trip.


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    High-quality machined finish

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    Very neat compact design

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    Works perfectly with mineral oil systems

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    No leaks


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    Limited fitting options as standard

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    More difficult to see bubbles from bleeding than a clear cup

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The Kiwi brand Neutron is relatively new to these shores. Its latest release is an Emergency Bleed Kit to go alongside its existing Ultralight First Aid Kit and Oh Sh!t Kit multi-tool that fits in your handlebar and wouldn't look out of place with the other products in our best bikepacking tools list.

The top cap of the Neutron Components Emergency Bleed Kit

The top cap has an extra thread to keep your bleed valve screw safe (Image credit: Neal Hunt)

Design and specifications

The Bleed Kit is essentially the same as the cup setup used by Shimano and Hope and is designed for you to do a ‘top’ bleed out on the trail or roadside. This involves removing the bleed screw on your brake lever, screwing in the bleed kit, and pulling the lever repeatedly until no more small bubbles appear.

The main body of the kit is designed to hold 10ml of either mineral oil or DOT fluid which is enough to top up both levers and leave a little in reserve. Although the seals used are designed to work with both types of fluid, it is really important that you don't swap between them without thoroughly cleaning it, as contaminated fluid could cause damage to your braking setup.

It uses a common M5 x 0.8mm thread which is a common size used by SRAM and Shimano, although, on later drop bar Shimano or Magura, you'll need to purchase an adapter to fit. The top cap is a nicely finished alloy and even includes an M5 x 0.8 thread internally to store your bleed screw in the top cap whilst bleeding your brake. It's a really nice little feature, as it's way too easy to lose the bolt on a dusty trail or gravel car park.

The whole thing is made from CNC’d alloy and comes in black with silver end caps. It is very compact, being only 75mm long and weighing in at 19g empty and 29g when filled with Shimano mineral oil.

Neutron Components Emergency Bleed Kit on bike handlebars

The Neutron bleed kit works really well with Shimano systems (Image credit: Neal Hunt)


For a Shimano brake, it works great as a bleed kit. The high-quality machining enabled a good connection, and a bleed was easy. I used it on an XT lever that was feeling a little mushy, and after a few squeezes of the lever, bubbles appeared, which resulted in a much firmer lever feel. Although it was easy to do, I actually prefer to use the standard Shimano cup in a workshop situation, as the plastic construction makes it easier to see bubbles coming through from below if the bike is in a stand.

For SRAM brakes, it is much less effective as you generally need the vacuum pull of a SRAM bleed kit to remove any bubbles in the system. Although, in an emergency situation as it's designed for, you could potentially use it by zip-tying your lever down for a while before fitting the bleed funnel to the top of your brake to drive air to the top of the system. By doing this, you encourage any air in the system to the top of the brake. Not ideal, but then I guess that's the point of an emergency kit.

It is very light at 29g when full, compact enough to go into your saddle or hip bag without it being noticeable, and the supplied Allen keys are actually surprisingly good. Bleed screws are small, so it's important to use a good Allen key to prevent rounding the bolt when removing. 

Currently, there is no UK price; Neutron ships direct from New Zealand, and the cost, including shipping to the UK, is 69 NZD which is roughly £32. It's certainly not cheap but is reasonable considering the quality of production and the fact there's nothing else comparable on the market.

Neutron Components Emergency Bleed Kit in a bag pocket

Its small size makes it perfect for keeping in a frame or waist bag (Image credit: Neal Hunt)


It's a great bit of kit, if a little niche, but it does work in many situations, from multi-day gravel epics to Alpine enduro adventures or uplift days. I'd also be tempted to keep it as part of my van tool kit, as it's perfect for sorting those niggly brake issues you often find just before setting off on a ride or for that one riding buddy that hasn't sorted their brakes pre-ride.

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Tech specs: Neutron Components Emergency Bleed Kit

  • Price: $31.50 USD / $50 NZD / £33 (depending on exchange rate)
  • Dry weight: 19g
  • Filled weight: 29g 
  • Volume: 10ml
  • Dimensions: 20x20x75mm 
Neal Hunt
Freelance Writer

Neal has been riding bikes of all persuasions for over 20 years and has had a go at racing most of them to a pretty average level across the board. From town center criteriums to the Megavalanche and pretty much everything in between. Neal has worked in the bicycle industry his entire working life, from starting out as a Saturday lad at the local bike shop to working for global brands in a variety of roles; he has built an in-depth knowledge and love of all things tech. Based in Sheffield, UK, he can be found riding the incredible local trails on a wide variety of bikes whenever he can