Gear Reviews

Giro Synthe MIPS Helmet Review: Protection at speed

The Giro Synthe MIPS is a fast looking, top of the range racing helmet. BUT it comes in two versions, regular and MIPS. The MIPS is a new fangled membrane supposed to prevent your grey matter turning into a smoothie if you come off the bike. So lets take a look at the Giro Synthe MIPS helmet, and seen if the science adds up! Warning medical images…

Giro Synthe MIPS Helmet Review

“Nooooo you heathen, why would you not ride with a helmet?!?”

“I’m a careful rider, I’ve never crashed, and I think the freedom gives me extra protection not to be complacent”

Yes there is a well publicised and raging argument between those who say everyone shoulder wear a bike helmet and those who say there is no benefit. I’m firmly in the “wear a bike helmet” category. But I understand some of the arguments from the bare-bonce camp. However a new bit of tech MIPS might address that.

There is even a raft of arguments in the scientific and medical literature about helmet safety or lack of effect – how much of this is argument along the lines of “There is no such thing as global warming” and how much is based around genuine lack of data I dont know.

The Arguments

Meta-anylses is probably as good as things get when it comes to science. You take as many other papers and studies as you can, which fit your criteria. Put them in an academic statistical blender (stats is a dark art as far as I’m concerned!) and look at the outcome. The BENEFIT here, is by combining lots of different studies, the met-analysis has more power to detect actual effects. Kind of like a statistical PowerRanger! Or Captain Planet depending on your age!

Giro Synthe MIPS

(Oh the mullets bring pain…. moving SWIFTLY on!)

So the Cochrane Collaboration got together in 2000 to turn their supergeek vision onto the issue of bike helmets

Giro Synthe MIPS

The group  concluded that helmets protect your skull, and squishy bits inside. I know, revolutionary. However it is vital to say that this work is not without it’s critics. There have been articles commenting both in support of, and against the Cochrane collaboration review. So there is going to be an element of evaluating the arguments yourself and choosing.

Personally after my slight tumble in 2015 with a fractured elbow, I’ve very much in favour of protection, heck even padding! But that is a personal bias.

However I do think it’s important I put forward an anecdotal comment from an ITU consultant whom I respect greatly. I saw more than a few cyclists in the ITU setting whilst training in the hospitals. Now if you hit your head, from any source, and have swelling inside the skull as a result, the surgeons get to play wit their toys – dont worry, I’m getting to the Giro Synthe MIPS in a minute!

Giro Synthe MIPS

The purpose being to put in one of these little gizmos. An intracranial bolt…. which is about as much fun as it sounds. This is essentially a tyre pressure monitor, but for your skull not your tyre, and allows the ITU team to monitor the pressure inside your head, to decide if they are going to act further – dont worry that is NOT going to be discussed within the scope of this review/ramble!

Giro Synthe MIPS

Flip of the argument

Amazingly the point about bolts and brain surgery is one of the argument AGAINST using a helmet. If you hit your head with such force that it causes bleeding within the skull, you are in trouble. BUT if you are wearing a helmet, it is likely that the helmet will protect your SKULL, but not your brain. So you brain swells inside a fixed box, leading to things getting squashed. There are at least THREE parts of my anatomy I’m against getting squished, my brain being one.

My respected consultants argument is that patients with severe head injuries you were not wearing a helmet tend to do slightly better as they will almost certainly fracture their skull… Which sounds VERY odd. But that fracture allows the skull to expand slightly, reducing the amount of internal pressure that can built up. Think about putting too much pressure in a bike tyre, from a pump which has a release valve set at a particular pressure. Without the valve, you keep pumping, your inner tube blows up (not good). If you have a fractured skull, or in this case a pressure set valve, when you go too far, the pressure comes out of the valve, rather than blowing the tube, not squishing your brain.

Yes, it’ a narrow case use, but it is a VALID point.

HOW the chuff does this relate to the Giro Synthe MIPS??!?

It’s all about the MIPS liner… which we’ll come to in a minute! So now I’ve put everyone off their lunch, lets take a look at the Giro Synthe MIPS – the top of the line, and most expensive Giro helmet. Coming in at around £200… which is a LOT of money for a helmet. About the only helmet not going to blush at that price is the POC Octal MIPS at an eye watering £250!

Giro Synthe MIPS Helmet Review


The Giro Synthe MIPS in my opinion is a good looking helmet.

Giro Synthe MIPS Helmet Review

It looks fast, which is, in my opinion a vital part of any cycling product. In the highlighter yellow seen here it looks even faster. (Note to self, make sure to buy next bike in yellow!)

Giro Synthe MIPS Helmet Review

There is also a range of much more sedate colour schemes available – I’m also quite partial to the understated titanium grey third along from the LEFT

Giro Synthe MIPS Helmet Review

On the front of the helmet are the seemingly ubiquitous sunglasses docking ports. The little piece of rubber with synthe written on it, is supposed to add a bit of sticky material to stop the glasses falling off. I might have liked to have seen this a little larger, just for peace of mind if nothing else. But your glasses certainly fit without any issue.

Giro Synthe MIPS Helmet Review


One of the things you notice very quickly with the Giro Synthe MIPS is how much air flow you get through the helmet – from 19 vents – I havnt had many aero helmets to compare it to, but certainly it feels worlds more advanced than my usual Caseco lid, which gets a little steamy at times! Certainly I did have the sweat dripping down in the same way with the Giro Sythne

How much of that is due to the vents, and how much is due to the padding, I’m not sure. But I know I was more comfortable in the Synthe

Giro Synthe MIPS Helmet Review

The pads contain X-Static fibres, Giro’s fancy name for silver containing fibres, which act as an antibacterial agent. Which is very nice on a bit of padding due to be rubbing on your head continually

Giro Synthe MIPS Helmet Review

On the back of the helmet is the Roc Lock system for tightening the helmet to comfort

Giro Synthe MIPS Helmet Review

Which draws on the plastic wires inside the helmet.

Giro Synthe MIPS Helmet Review

I’ll be honest, looking at the small amount of padding and the flat wires, I wasn’t really convinced the Giro Synthe MIPS was going to be very comfortable. Very much looking like a race day type affair.

I couldnt have been more wrong. Genuinely the most comfortable helmet I’ve worn!! Yes the dial at the back could do with being a little bigger in order to get a better grip with gloves, but that is a minor complaint to have when things are as comfortable as this!

If I was going to be critical about anything on the comfort side of things, it would be to add a chin strap, similar to my Caseco helmet

Giro Synthe MIPS

That’s about it isnt it on the helmet front?


BUT what about the MIPS?

MIPS stands for: Multiple Impact Protection System.

I’m sure that anyone who has been looking at MIPS helmets has seen in various MIPS videos

MIPS is actually a technology licensed from Sweden – who as Volvo are keen to highlight are one of the most safety technology progressive countries on the planet.

MIPS is essentially a low friction liner within the helmet, seen here inside the Giro Synthe MIPS. Giro Synthe MIPS Helmet Review

The purpose of the liner is to allow the riders head to move within the helmet, in the event of a crash. What is the point about that? Well it comes down to vectors.

Yes I had to back to some of my A-level physics stuff for this. So here is an image from RopeBook.com which explains it quite well

Giro Synthe MIPS Helmet Review

What on EARTH does this have to do with a rider?

OK, you are bombing along. You crash the bike. You have a forwards momentum, in the direction you were travelling, and now a side ways momentum, as you are falling. SO lets have the wheels slide, going forwards, and going to hit your hit, on the side you are falling, so that is out 170 angle above. If you are a 100Kg, rider, than is a HUGE force going through your skull, and being translated to the brain inside.

When your brain hits with that force, it suddenly changes direction – think about moving a snow globe quickly. The fine spiders web of neurones inside your head doesnt like this, and they break. This is called a diffuse axonal injury.

Giro Synthe MIPS Helmet Review

In my opinion, excluding an injury that kills you out right, or is ultimately life ending, this is about the worst injury you can sustain. Full stop.

MIPS works by allowing the helmet to move when your head does strike the floor, changing that angle, as you can see in the below video from the MIPS site

By reducing the angle, the rotational acceleration, and the force through the brain is reduced. But does it matter?

MIPS has some pretty dense R&D papers on their site. I’m not an engineer, but from my interpretation, compared to a helmet that is clamped down on your head with no movement at all (not really likely) MIPS reduces the forces on your brain by 50%. If use a “normal” helmet, using Telfon to simulate movement inside the helmet (which will probably have less friction than you scalp would normally, so is a harder test for MIPS to compare against), MIPS by comparison still reduced the forces by around 12%

MIPS Conclusion

MIPS adds to the price of the helmet, without a doubt. You can get a Giro Synthe without for about 70 less. Which is a big chunk of change. HOWEVER, MIPS is available on a large number of helmets now, adding only £20-£30 to the price. From what I have seen from MIPS in terms of force reduction, and my own experience with patients with diffuse axonal injury. Until the technology is replaced with something better, EVERYONE of my future helmets will have MIPS.

Giro Synthe MIPS Conclusion

Honestly the Giro Synthe MIPS is a great helmet, as the Synthe, without the MIPS is a great helmet. You can pick up a Synthe without MIPS for £130-140. Which I think is a fair price given how astonishingly comfortable it is, and the range of colours out there to match your bike.

At nearly £200… that is a lot to pay for a helmet, especially with Giro’s own Sonnet and Savannt are available for £100, with MIPS. At £140, the Giro Synthe MIPS would be without a doubt a no brainer. Adding that extra £60 does give pause for thought.

As it is, I’d put the Giro Synthe MIPS at 9/10… Personally I think it’s going to be hard to find a better helmet this year



  1. Very cool to see the medical and extra physics additions in your review. However the additional safety cannot be expressed in money, when you would need it in a crash. So for that extra safety on my road bike I’m willing to pay the extra amount. 🙂

    However I agree that the Giro Synthe MIPS is a fantastic helmet …

  2. That was what was simulated using the Telfon liner. As you are completely correct, you normally get movement anyway. The MIPS liner had a reduction of 12% compared to that.

    Plus if you helmet is not enough you risk other issues

  3. For the sake of argument, if your regular helmet isn’t tightened enough, it would also allow some rotation, as the mips offers.


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