Hi guys. I have been lucky enough to be one of the beta testers for the upcoming G-Belts from SimXperience. I have been testing the G-belts for the last 5 months and I would love to share my impressions and feedback with all of you.

1. Overall impressions

I have always been a big fan of belt tensioners in Sim Racing. Many years ago I built my own passive system, which just used springs and the motion of the seat mover to give you a sense of braking. While this did give you some feedback, it was never very direct or powerful. So, when I saw that SimXperience was doing a dual axis active belt tensioner then I could really see the potential for it to be great. Having the rest of the SimXperience ecosystem I jumped at the chance to test out the latest addition to their ever-increasing range of motion devices.

First time out on the track you are immediately hit by the extra layer of immersion that the belts give you. From the first corner when you feel your shoulders and chest being pulled tightly by the harnesses. Back in the day I used to race my classic Hillman Avenger, and I still do track days in my V8 Avenger wagon. This gives you the same feeling you get when you are hard braking into a corner.

As braking is one of the most important areas of Sim Racing,  naturally this is where the G-Belts shine. Being able to feel exactly how hard you are braking is so important when you are Sim Racing, and this is exactly what feedback the belts give you. You can feel the pressure of the belts increase as you brake harder, and the moment you lock up you feel the belts ease up as the G forces drop when you start to slide. This alone for me is worth the price of admission. It makes it a must have for fans of immersion, or just anyone looking to get more feedback in to what the car is doing under braking.

Some of the other effects it adds also brings a lot of immersion to the Sim, going through the carousel or along the back straight at Nordsclife, you really feel every bump as the belts ever so slightly tighten and loosen. 

Which also brings me to another point that some people might wonder about. When I say the belts tighten and loosen, they don’t get so loose that they feel like they are falling off- it is more of a pressure sensation. When you get in the rig, you do the belts up tight like you would in a normal race car, and as the belts tighten then it feels like you are moving forward into the belts under braking. It is probably the most unimpressive motion system to watch as a third person because you don’t see much happening, much like the GS-5 where everything is happening under the surface. But when you feel that pressure, my god does it throw me right back in to my old racing days.  

With Sim Commander’s new cloud tuning, the tuning for each car takes zero effort- just leave cloud tuning on and it is perfectly set up for any car you drive. Since cloud tuning was implemented, I haven’t had to change one setting on the G-Belts, or any of my SimXperience gear, it just works.

2. Packaging 

Because I was one of the beta testers I am not sure if this is any indication of how the final retail packaging will look but it came well packaged. It came with the controller box, USB power cable, USA power cable, short power cable with a switch, SimXperience badge (This comes separately depending how you are going to orient your G-Belt, on the seat or below the seat) and finally the G-Belt unit itself. 

The Box...

All nicely bubble wrapped

The controller box and power cables

The G-Belt unit itself

A close up of the G-Belt

3. The motors

The motors are the same beefy motors that are used in the GS-5. The motors are a high torque Nema 23 SM57HT82-3004 stepper motors which clock in at a massive 1.2kg each, without the gearboxes. This give them tons of torque, and great detail.

For scale

4. Mechanism

The mechanism uses an arm which is directly attached to the end of the gearbox that pulls the belts back.

5. Installation

Installation was easy, just two bolts holds the G-Belts to the back of the seat, then you just feed the harness through based on the diagram on the SimXperience website. This will differ depending how you have mounted the G-belt. The G-Belt unit is really heavy, so the hardest bit was lifting it while you bolt it in. I did it by myself, but it might be easier if you get someone to screw the bolts in while you hold it against the back of the seat.

The mounting holes

I coiled my excess harness under the G-Belt

6. Power and torque

Using such large motors, it really can put the squeeze on you, quite literally. I remember back when I used to race, I would feel quite sore in the shoulders after a race, with the G-Belts turned up to the max you can definitely replicate that feeling. If you don’t want such a workout then you can turn them down. I don’t think you would want any more powerful, unless you were a masochist, or you know a good masseuse.  

7. Detail

Again, using such big motors they are able to reproduce all the fine details in all the bumps and surges. You can really feel just how hard you are braking and how the car is responding under you. This is a real game changer when it comes to braking.

The dual axis really helps here also. having the ability to tighten each belt independently means that it feel like you are being pushed sideways around the corners. Adds that extra layer over a single axis system. 

8. Build quality and robustness

As with all the SimXperience gear, this is built like a tank. I can’t feel any flex in the system. I have been using it extensively over the last 5 months and it hasn’t skipped a beat.

9. The comfort

If you have the strength turned up too high, then you definitely can make it feel uncomfortable, but if you are used to race harnesses and real race cars, then the same is true for them. But if you don’t go too overboard then they are comfortable. I use 3” belts which do a good job of spreading the load out. I use a 5 point harness which I thoroughly recommend. You really need that submarine strap to stop the belts riding up under braking, so I wouldn’t recommend 4 point. During the beta, there was some people who modified their 5 point belts to become 3 points, just the shoulders and the submarine. I tried this myself, but it didn’t work for my body type so I stuck with the full 5 point as it pulled the belts tight against my chest.

10. The feeling of G forces

This is where the G-Belts shine. The feeling of the braking G Forces is what this system is all about and it does an amazing job of it. As I have said previously, the extra added feedback you get under braking is a game changer. There is an effect to loosen the belts under acceleration, but I didn’t find that as useful because you don’t really get much feedback through the belts in real life under acceleration. I find the GS-5, full motion or wind simulators do a better job of acceleration effects, but if it is the only form of motion you have then it does give you some sense of acceleration. The dual axis motors do also give you a good sense of lateral G forces, especially when combined with other motion systems.

11. Road bumps

Road bumps is an interesting one. At first, I didn’t really like them, but as I got used to them then it felt more and more natural. They work really well in addition to other motion, but if it is stand alone then at first they stand out a little bit too much. If you are using it stand alone, and you do find the road bumps too distracting, then turn them down and slowly increase them until they feel normal. 

12. The feeling both as a standalone and to compliment an existing motion simulator

As my first test I wanted to test it with one of my existing profiles so I picked the F3 car in iRacing with cloud tuning turned on

I wanted to test it with all my other motion enabled so it was closest to the setup that I'm used to running. I am used to running a passive belt tensioning system with springs pulling against the movement of the Stage 4 seats, so I am used to having some feedback when braking from the belts, but with the G-Belts it was next level. After the first corner I loved it. They work so well with the rest of the SimXperience products, you feel the panels and the belts working in unison, each adding a different element of the G-forces to you.

My next test was to break it down to just the G-Belts and then added other motion devices in one by one. Here are my experiences.

G-Belts only

With only the G-Belts, the feeling of braking and cornering was really good, you could instantly tell how hard you were braking, which 

given how important braking is, is quite invaluable. I found that some of the bumps didn't feel that natural with no other feedback from the seat below. The braking in to corners still felt amazing. but without the GS-5 to fill in the rest then the road bumps felt a little odd. If I were to run it with G-Belts only then I would probably turn down the bumps a little, but as I was planning to add in the rest of the motion, I left the settings where they were. I think with some minor tweaking then you could get it to be a good standalone motion addon, but in a different way to the GS-5 or Stage 4 alone. As a standalone unit then braking is where the G-Belts shine, if braking is the most important thing for you then the G-Belts would be a great addition, but they don’t do as much for cornering as the GS-5 or Stage 4 would. But then it is a very cost effective way to get your foot in the door in motion without shelling out for a GS-5 or Stage 4. I guess I am a bit spoilt in that regard. But don't get me wrong, it is awesome standalone, and it gets even better when paired with the other motion systems.

G-Belts plus GS-5

These two work really well together. It totally fixes my problems with the bumps on the G-Belts because now you are feeling the bumps in the GS-5 and the G-Belts so it does feel like you are actually getting bumped around in the seat. Cornering G-forces feel great because you have the panels and the belts working together. And the braking is even better because not only do you have the pressure from the belts, you also have the pressure from the panels under your legs.

G-Belts plus GS-5 plus Stage 4

This is when the magic happens. They all work so well together so you get all of the motion cues combining harmoniously. Truly amazing. I understand that this type of setup is out of the reach of most people, and I am very fortunate to have 2 full motion rigs. I think any motion is a great addition to your rig, and with the SimXperience ecosystem it all works so well together. I don’t think you can really go wrong with any of the SimXperience motion options.

Now as another test I wanted to go the other way and turn off the G-belts after I was used to them.

GS-5 plus Stage 4 with No G-Belts

This is where things got really interesting. After running some laps with everything on and then switching the G-Belts off then I found I was missing my braking on corners, locking up, all sorts of horrible stuff. It is amazing how quickly you come to rely on the feedback from the G-Belts, you can tell exactly how hard you are braking, and when you are going to lock up, just like in a real car. So when you just switch it off when you are used to it then your brain sort of panics because it isn't getting that feedback, it was almost like my brain was telling me to brake harder because I couldn't feel the pressure from the G-belts, and subconsciously my brain interpreted that as I wasn't braking hard enough. Which is really odd, because I didn't feel that as much going the other way, when I switched off the motion and GS-5. It really shows how valuable braking feedback is and how much we rely on it, more so than cornering G forces I would say.

Zero motion or G-Belts.

Man, this was painful. It’s like I had a limb cut off. With no feedback from the car at all then I felt so disconnected from what was happening in my VR headset (As a total torture test I went back to no motion or VR and I couldn’t drive at all!!)

13. A brief comparison to the passive belt tensioners and what it has improved on.

My old spring based setup gave me some feedback, but it was so indirect, because it was relying on the movement of the seat then being transferred through the belts. It was like hearing about the braking in the third person. With an active setup then the feedback is so much more powerful and direct. I watched a Youtube video of an old 1996 Thrustmaster wheel that used a bungie cord, and the passive system was sort of like that. The G-belts, on the other hand, are like a direct drive wheel… for your shoulders.

My old system

14. Looks

I love the looks. It has that classic SimXperience aesthetic. The cut out G-Belt logo with the brushed aluminium insert looks amazing. And the chrome SimXperience logo looks like it would be at home on one of my classic cars.

15. Controller box

This is the classic SimXperience controller box. The same as the GS-5, Stage X and Accuforce. This means I now have 4 of these big controller boxes, and they do take up quite a lot of space by the time you have 4 of them. 1 or 2 isn’t bad, but I do wish you could consolidate them down into less boxes.

16. Noise

Other than the fan in the controller box, it is pretty quiet. Just a little servo squeak here and there

17. Sim Commander

SimCommander has improved greatly over the last few months with the addition of cloud tuning. This means you can just tick a box and it will automatically download the best tune for that car and track combo from the cloud. No more manually setting up each car or dealing with lots of profiles. You can still go in and tweak settings if you like, but since cloud tune was released, I have just been using cloud tune.

19. compatibility with other seats.

If you have a hard backed seat then there is a template you can use. You just need to line it up with the cut out for your belts and then drill two holes. If you don’t have a seat that would work for drilling in to then they make a universal mount which bolts on underneath any standard seat, so you can retrofit pretty much any rig out there that uses a racing style seat.

The template on a GS-4

The Universal seat mount

18. Summary

I really loved the added effects that the G-Belts add to my existing rig. It looks amazing and the install was simple and easy. With how important braking is then I think it would be good as a standalone addition to a static rig. And for those who already have motion, then it is an essential addition to any motion system.

Overall, 10/10 Love it. Especially with all of the other SimXperience hardware working together.

I love that it does feel very different from car to car, depending on how quickly and sharply they brake. You can really feel it in a big heavy car that is quite lumbering under brakes, versus a high downforce light car which is super fast on the brakes.

It is also amazing how quickly you learn to rely on it. You can instantly tell exactly how hard you are braking and then you learn how hard you can brake in that particular car. I think that is where the true power of the G-Belts is, and that is true even as a standalone system. And because braking is probably the most important part of racing, then by proxy it makes the G-belts one of the most important motion systems.

Also, my cat very much approves of the G-belts