• Coach Sooty

Wheel size and WHEN to change

It’s a constant issue… wheel size, and when to change up, from 90mm, to 100mm, or 100mm to 110mm… and now, from 110mm to 125mm. So we’re going to examine it here. Not that it hasn’t been said before, but that we just think it could do with clarifying.

The main problem or ‘challenge’ is ‘deck height’. Deck height is the height of the foot from the floor with any particular set-up. Deck height is usually measure from the axel center to the top of the frame, and the crucial measurement is to the front deck (or boot mounting). But the real practical height is the most important this is the height from the floor to the top of the deck WHEN THE WHEELS ARE IN PLACE. This is called overall deck height. Or realistic deck height.

We’re going to split the issue up in to 2 situations; 1. Kids and 2. Adults. Although the theory and reasons are largely the same, the application of these is a little different. Also, it helps you the reader to imagine the situation and relate it better to your coaching of the people you know and are familiar with if the issue is split in to these two categories.


This means anyone under 18, or anyone who is still naturally physically developing. And most coaches get the decision about when to change up to a bigger size wrong. Every coach and parent wants their kids to be happy, and so they want them to be fast, and maybe they believe that winning brings happiness. (This may or may not be true, but is a massive subject, too big to be discussed here.) Either way, most coaches believe that bigger wheels are faster. This is true, but it is not true if the bigger wheels are at the expense of control and stability. And it is definitely not true if the bigger wheels (and thus increased deck height) reduce endurance ability (i.e. the skater gets more tired, more unstable and thus reaches ‘breaking point’ earlier in the race.), foot cadence, manoeuvrability, skills and power output (top speed). Of course, this is very difficult to see clearly, and most coaches think it’s not happening, because by that time they are used to seeing the skater skate in that way. So it becomes normal.

So what are the criteria for wheel size selection?

Body size and strength

Co-ordination skills (i.e. control).


Ankle strength, and therefore ankle stability.

Big body size doesn’t automatically mean strong, and it certainly doesn’t mean that the child/youth has control over their skates/ankles, or that he/she is stable enough to go to bigger wheels. Often, the child that grows fast and early is the one with the least control over their body. (Believe me, I know this, I was nearly 2m tall when I was 14!) They may be winning races, but on raw power, and because they have a higher level of all those new teenage hormones in their body, because they grew before their friends. They are on their way to adulthood early, but this doesn’t mean that they should be on big wheels. (Especially not just because “it looks right, and fits their body”)

Bigger wheels don’t just mean a higher deck height, although this is the most important factor. The secondary factor is a little hidden; it’s gyroscopic effect.

The gyroscopic effect can be felt by holding a skate in your hand, preferably with big wheels on, then spinning the wheels as fast as possible with the other hand, then extend your arm out straight, then try to move the skate around in the air.

You’ll feel resistance to movement, seemingly from nowhere. This is the gyroscopic effect in action. It is especially powerful at high speeds and with big wheels.

It’s affecting you while you’re at high speed, balanced on one foot, on a balance area about 2mm wide, on possibly bad asphalt or going round a banked corner, whilst being pushed by another competitor, when your legs are tired and burning at the end of the race. null(This is why a 10 minute “test” of new wheels on fresh legs is meaningless). This affects co-ordination, stability and foot speed. THIS is what is causing your kid to be slower, less skillful and possible dangerous.

The bottom line is that it is all too common to see young kids on wheels that are clearly too big. Everyone can see it, except the coach and the parent.

The bottom BOTTOM line, is that the longer you can stay on smaller wheels, whether you are a young skater, or an adult that has been skating for 5 years or less, or is still developing stability, balance and control, the better. Stay on these small wheels guys, until you believe you are expert, and someone else agrees with you.

By far the biggest negative to big wheels is that children who rush on to bigger wheels do not learn BASIC skills so well, nor so thoroughly/deeply as a child on smaller wheels. (And learning new skills, and looking skillful in front of their friends gives kids just as much self-confidence and happiness as winning does.)

The problem is, there is no real test or way to judge when it’s right to change, it’s a combination of factors, and it’s mainly down to experience (of the skater and/or coach), and a keen eye to spot small mistakes, instability etc. It’s not a science.

Although one good test I’ve found works pretty well is to get them to play roller hockey on the “new big wheels”. If they look like an amateur, and they can’t turn, stop, start accelerate like normal, then they’re not ready for the bigger wheels.

However, Colombia, the most successful skating nation uses these rules:

8-9 years: max 80mm

10-11 years: max 84mm

12-13 years: max 90mm

14 years: max 100mm

15+: 110mm

These are the MAXIMUM allowed, not the recommended. If you want to learn better skills, then stay on smaller wheels longer.


So what’s the difference with adults? Well, in most cases it’s EGO. Most adults think 90mm wheels are for kids. Well, guess what, they’re not. They’re for you, if you have been skating less than 2 or 3 years. Yes. You. It’s astonishing how many people I see who have absolutely no control over their 110mm wheels, can’t get on the outside edge, not even 1 degree, they have problems stopping, turning, and avoiding dangerous situations, and they admit they are nervous in the pack. Hey, guess what, that’s because you don’t have control over your skates! … because your foot is too high off the ground, and you haven’t learnt to control the gyroscopic energy in a big wheel.

By far the biggest negative to big wheels is that adults who begin on bigger wheels do not learn BASIC skills so well, nor so thoroughly/deeply as a n adult who works their way up to big wheels over a few years, starting from 90mm.


If you are lower to the ground, your ankles are stronger and you will react faster, turn better and feel safer on your skates. You will also relax more and be more efficient over a longer distance because you are relaxed. So in a real race situation you’ll skate better, faster, longer and safer.

I guess by now you must realize how insane it is to see some “fitness skaters” or kids trying out 125mm set-ups. If you look like Donald Duck when you skate, then you should probably buy some smaller wheels pretty soon. (or at least go back to basics with hours and hours of basic drills, and stability squats on the wobble board to strengthen your ankles, although this won’t give you the co-ordination skills you need to control the skate when in motion.)

I’m pretty sure this article won’t make any difference at all, because ego is a powerful thing, and everyone thinks “Yeah, but I’M not one of those guys on too big wheels, that is just those other guys”. But at least I’ve said it again, and at least people might understand the issue a little more. Let’s hope so, especially for the sake of kids ankles.

Who do you know who is on wheels too big for their skills? And when are you gonna mention it to them? Or at least suggest they read this article?

Let’s go faster,

Coach Sooty

p.s. Need more advice and guidance to make your training more effective, and to go faster? Click here, we can help.


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