OZ ATV :: The Australian ATV Forum

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I just got a set of Fury SX for my 2014 X MX and thought I'd share my opinion to those interested in a read on the technical considerations.

I decided to try 20 inch diameter tyres all round. There are positives and negatives for doing this on a Motocross Quad before you even look at the actual model of machine.
One advantage is the taller sidewall of a 20 inch rear on a 9 inch rim should always offer a smoother ride, and I'm not getting any younger so that one got a big tick.
The main disadvantage is the heavier rotating mass of a 20 inch tyre over an 18 inch tyre mechanically slows the machine and for my choice it added 16mm to my Centre of Gravity at the rear which is not good for cornering.

Personally, I hate having heavy rotating masses at the back corners when jumping, so I was always going to be picky about this aspect. It turned out that they jump fine. I can feel a bit of extra weight but only just. The Fury's are a pretty light 20 inch tyre and I went for a Fury rolled edge rim for the offset weight saving. The total wheel weight is maybe only 500 grams heavier when compared to what I had on the beadlock rims.

The first thing I noticed when riding the DS was how much taller the gearing was. The Fury rears measure around 19.4 inches with 5.5psi in them. My ITP SX 18 inch rears measured almost exactly 18 inches, so there is a diameter difference of 1.4 inches which equates to about an 8% gearing up. So I whizzed back to the shed and went 1 tooth down on the front sprocket to put me back in the ballpark I was used to.
The next point is I only fitted Fury 20 inch fronts, so the bike actually tilts forward more. This alters your effective caster angle, because the frame that all your A-arms bolt to is now high at the back. With less caster the steering must feel a bit lighter or quicker and more twitchy.
At 19.6 inches tall, the Fronts were about 4mm taller than the Quadcross MX that I was running and the rears were 33mm taller. All up I gained 2mm more front ground clearance and 16mm more at the rear. In one way the DS's don’t mind the extra clearance because with 11.1 inches of rear travel they often bottom out the chassis rail on big landings. Having said that the Can-Am back ends sit a bit high too, but if you are sitting high and still bottoming out, then you are using a lot of suspension, and that's a very good thing. So the 16mm extra clearance under my feet is a welcome thing and I'll just have to tune riders sag height another way.

The rear Furys are a semi round / flat tyre shape which also makes them smooth and predictable. Another aspect you will realise with a bigger diameter rear tyre is the longer contact patch should give better straight line traction. Add the taller sidewall will allow better compliance with any rough track surface, and you should notice more traction to get you where you want to go. Also, the Fury's I chose are the 'Green' label, which are their 'Soft' compound.
Altogether, I definitely noticed a much stronger feeling of straight line traction. They hook up very well and deliver a lot more torque to the ground. The Can-Am is not a particularly strong bottom end motor so I had to go back that sprocket tooth to maintain the same overall gearing to be able to keep in the same power range, but I think stronger bottom end engines like Honda or Suzuki might welcome the taller gearing and churn the 20 inch Furys with low end torque no worries.

Slightly lowering your rear spring pre-load is probably required to keep your ideal ride heights. I also found the back wanted a tad more rebound to feel right. I'm not exactly sure why on that one, but 2 clicks of the adjuster fixed that.

The Fury 'Soft' compound is nowhere near as soft as some other brands and probably falls closer to a medium soft compound description. But who cares if they hook up fantastically. I am very happy with their definition of 'soft' and not being ridiculously softest, I'd rather have the longer lasting wear characteristics that the slightly firmer rubber will produce.

Back to the riding, Lisa and I both kept riding and adjusting the Can-Am to maximise the advantages. Remembering that it is always good to tune the negatives out and not focus solely on the positives that you or your machine already do very well.
The 20 inch Fury tyre set ended up being very comfortable and gave more usable traction while still sliding predictably. While I noticed the slight increase in the bigger rear wheel 'flywheel' effect, Lisa did not. She only noticed increased smoothness and traction advantages.
The added ground clearance can also be a good thing for a less experienced rider on a rough or deep rutted track too. Even as a more experienced rider, the 20’s are easier and more forgiving which will mean less fatigue. That should translate to better lap times in the later stages of any race.

The 20 inch fronts (that normally pair with the 18 inch rears) are a full round shape with a centre Mohawk design. They are the same soft compound and have a very plush, smooth feel without being wishy-washy.
The centre rib works very well directionally but is not as aggressive as something like the Razor 2 pattern which can be too knife like for some peoples liking. I think the Fury's steering grip and smooth predictability is about spot on the best compromise. Under brakes they are equal to any top shelf tyre.

We will both be running Fury 20's all round for this MX season. No doubt there will be more developments and tweaks so if anyone has any questions... I'll be happy to answer.
We'll be putting them to the test at QuadridersSA's Loveday MX event this weekend.
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Can-Am X Team
Bullet #Y12. MrsB #Y18.

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The Fury's went well at Loveday. Admittedly it is a pretty sandy track and any 20 inch tyre should be better in that environment.
The hard pack bottom is very abrasive sandy clay (like brickies sand) and Lisa and I both ran the same Quad for 4 rounds each (8 races in total) plus 2 practices of 3 laps each.
I did not flip the tyres side to side so the drive edge wear is quite evident.
But I'm very happy with the wear considering they are a soft compound that more or less did 2 and a half MX events running the same direction.
'soft' generally equals faster wear, and if you are getting something for your money... it's nice to see a traction improvement.
I got heaps of that.
I would not consider myself the best at holeshots by a long stretch.
But on the weekend I managed 2 out of 4 clean holeshots and I was either level or right there for the other 2. All on a dead stock Can-Am.
I think I can safely say they offered a solid advantage off the start line.
All up they were a very good match for that track.

I hope this review is useful or at least interesting to someone
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Can-Am X Team
Bullet #Y12. MrsB #Y18.