OMG - really confused about bike sizes

[Doublebubblegum]

My nearly 10yo desperately needs a new bike. DH takes him up to Halfords tonight, comes back with a new bike which apparently was the right size in the shop after the guy in the shop measured him and my son tried the bike.

DH builds the bike and it's bloody massive! Turns out it's an adults XS bike. I think it's too big and heavy for DS to manoeuvre safely. Why would a 9yo need an adults bike? My son isn't abnormally tall for his age or anything. He also is now saying it's hard to get on/off the bike as even with the seat at its lowest setting it feels too high. Aaaah. And he's obviously tried it on the driveway so now I don't even now if we can return it. It was quite expensive and I'm probably unreasonably annoyed at DH for deciding this was the right one to get.

When I've looked online at bike sizes I've confused myself further.

What size bikes do your 10 yos have? DH saying all the kids bikes are way too small.

Im sure when they measure they measure wheels and bike frames, and yes it can be confusing

I have a very small inside leg, went to buy a bike this year, and not one in the shop could I throw my leg over - had to order a step through

I personally would struggle with a "shopper"style bike even though I wouldn't be able to get a full leg flex

If your son can sit on the saddle, throw his leg over, and touch the ground with most of his foot - it fits, Even tip toes it probably fits because getting a full turn of the wheel flexing the knee is preferable then not

Thanks for this. Hopefully bump for any more bike insight?!

If he can sit on seat (just) with feet (toes) on the ground I think it’s ok. If not, I’d go back to halfords as you’ve been sold the wrong size.

How tall is he? A 10yo boy could be the same height as me and I have an xs or even an xxs womens bike.

A lot of people think you should be able to reach the floor with a foot when sat on the saddle but that’s not true. However I appreciate for a kid who might not be very confident being able to do so might be more important.

If you can reach the ground your bike is too small. But I appreciate I’m talking from an adult perspective, I have no idea about kids and bikes. All of my bikes I have had professional bike fits for and I can’t touch the ground on any of them while sat in the saddle. None of them are too big.

Halfords bikes are like tanks so even if it is the right size it will be bulky and heavy. I would return it and look out for a better lighter bike (like a woom bike) secondhand online.

Halfords bikes are awful and v v heavy. If you can, I'd return it and look for something else. If he'sno my ten and still growing, look on FB marketplace etc for a 2nd hand one. You'll get a much better bike for a fraction of the cost and can put it back on there to sell when he grows.

We are taking our 10yo to the bike charity shop near us to get him a new second hand bike as he has really taken a stretch. They are brilliant at sizing people for the correct bike frame.

Sounds like your DS may have a bit of growing to do with that bike!

Im.not a confident cyclist so DP fitted a saddle that goes up and down with a button on the handlebars. When I'm stopping it goes down so I can put a foot down with out coming off the saddle but then can raise it when I'm riding. I like the security.

True about Halford bikes not being great. I’d get cleaning the tyres with a wet wipe and take it back 😁. Second hand off fb market place is good for kids bikes. Or if you have somewhere like a forest place/national park near you which does bike hire then it’s end of season, you could ask if they are selling any bikes. I used to get DD’s bikes from bike hire places, ex hire stock.

Yes dropper posts are good, I have one on my mountain bike. On my road bikes I’m happy just knowing I need to bob down off the saddle at junctions.

How tall is your son? An XS bike is going to work for about 4'10" or over.
The next size down would be a kids bike with 24" wheels, did he try any of those? IIRC our boys went direct from a 24" to a S adult bike.

For a child they should be able to put toes on the ground whilst sitting in the saddle, with some room for adjustments as they grow. Can he do that with the saddle at it's lowest?

My average sized 11 year old rode an adult small Specialized Rockhopper hardtail with 27" wheels. He's 13 now and it still fits him. He tried the XS and it was OK, but there was no room for him to grow on it.

Depends on the size of your son. They might have felt he wouldn't get long enough out a kids 24inch wheeled bike.

My DS loved his 20inch bike and clung to it longer than he should have, when he was ready to change. The next size up was 24inch he wouldn't have got long out of it so ended up with a small adults from Decathlon. He was 12 but hes a tiny kid.

Here’s a guide by frog bikes - they are well made and worth buying second hand

https://www.frogbikes.com/en_ROW/fitting.html

With bikes its important that when he's in the saddle his leg can stretch with just a slight bend in the knee.
Any smaller and he will damage his knees, be in a lot of pain and won't be able to ride as efficiently.
I can easily see a 10 year old needing an xxs frame size.

Halfords bikes are like wrought iron. Search the second hand pages for a Frog bike.

I took my 9 year old daughter in to Balfes to be sized for a new bike and was shocked when they suggested an adult xs. She is now happily riding round on a trek xs bought off marketplace and hopefully it will last her a few more years.

I've just measured him! He's 4 foot 9 and a half....

He's taller than mine was when he got his xs adult bike.

At that age my DD would only buy her daughter a bike with an aluminium frame as they are much lighter in weight .

My 9yr old son is 144 cm he rides a 24inch wheel but my 11 yr old has a xs adult bike which my 9yr old can happily ride too. I think as long as they can put their toes to the floor they are ok.
agree with others about Halfords bikes though they are far too heavy my son has a 2nd hand frog which is so much better.