Adding gears to a kid's bike...

[livpoksoc]

My son's (8yrs) caught the bug, and wants to be out and about on his bike as much as possible - however he's quickly finding one gear isn't helping him when we use some of the moderate tracks around here.

I'm curious to know if anyone here knows if it's possible, and if so, how we could change his bike to include some gears. He has a Trek Precaliber single speed, but in the same frame size they sell a 7 and 8 speed, so I am hoping it's something relatively easy to do?

He has this: www.trekbikes.com/gb/en_GB/bikes/kids-bikes/kids-hybrid-bikes/precaliber/f/F427-2/precaliber-20/36271/?colorCode=greydark

 

[Jameshow]

My son's (8yrs) caught the bug, and wants to be out and about on his bike as much as possible - however he's quickly finding one gear isn't helping him when we use some of the moderate tracks around here.

I'm curious to know if anyone here knows if it's possible, and if so, how we could change his bike to include some gears. He has a Trek Precaliber single speed, but in the same frame size they sell a 7 and 8 speed, so I am hoping it's something relatively easy to do?

He has this: www.trekbikes.com/gb/en_GB/bikes/kids-bikes/kids-hybrid-bikes/precaliber/f/F427-2/precaliber-20/36271/?colorCode=greydark

You need to check if the wheel is dished to accept a free wheel ) cassette.
You need to check the frame is the same with cable housing or run a full housing and cable.

 

[Reynard]

In theory, yes, why not. In practice, it would largely depend on the width of the rear triangle between the dropouts. And also, whether the conversion is financially viable by the time you've costed up the parts.

Assuming it is the same frame (the link doesn't really say) as the geared model, and the same dropout width, then it'd just be a matter of sourcing a compatible rear wheel fitted with a freewheel, a compatible twist or trigger shifter, a derailleur and a derailleur hanger, plus the cables. And you would need the wheel, as a single speed wheel has different dishing compared to a wheel that's got a cassette fitted.

If the dropouts on the single speed are narrower than on the geared bike, then you'll be stuck with what you've got.

You might well be better off looking for a second hand geared bike rather than buying the parts and doing the conversion.

 

[oxoman]

You would be better getting a replacement bike and assuming it comes with twist gears get it converted to trigger. Kids hands struggle with twist gears, I've converted my sons bikes in the past for this reason and am about to convert my grandson's for the same reason. Loads of 2nd hand bikes available, you should be able to get a good quality bike for a reasonable price.

 

[FrankCrank]

As alluded to above, it can be done, but not cost effective unless you already have the parts knocking round the place.
Also, looks to be an aly frame, so the spacing between the dropouts would have to match any new derailleur wheel, you can't cold set the frame in the same way you can with steel.

 

[cyberknight]

You would be better getting a replacement bike and assuming it comes with twist gears get it converted to trigger. Kids hands struggle with twist gears, I've converted my sons bikes in the past for this reason and am about to convert my grandson's for the same reason. Loads of 2nd hand bikes available, you should be able to get a good quality bike for a reasonable price.

I agree , it's probably cheaper to get a second hand bike with gears .

 

[Punkawallah]

The cost in time and money might make another bike sensible. EBay rear wheel, derailleur, cabling and shifter runs to about £45, assuming you have the knowledge to make it work. Swapping out the chainset to a triple would be about the same.

 

[Big John]

Where would you locate the rear mech? Anyone spot a hanger? You could arguably use a geared rear hub such as a Nexus but the cost would be astronomic. If ever there was an excuse for n + 1 this is it 👍

 

[Punkawallah]

Where would you locate the rear mech? Anyone spot a hanger? You could arguably use a geared rear hub such as a Nexus but the cost would be astronomic. If ever there was an excuse for n + 1 this is it 👍

Assuming a solid rear axle (and adequate clearance), something like this would do the trick:

 

[MichaelW2]

A 3 speed hub might work.

 

[fossyant]

Get a newer bike that's a bit bigger, and sell on the single speed. It's not going to be cost effective trying to convert, and he'll be growing by the second !

 

[Elybazza61]

Better off selling the current bike to fund a decent second hand geared bike ; it is possibly do-able but you won't get the cost of the conversion back.

Also if he is getting too big for the current bike look to get something he can just about ride as it should last a bit longer.

 

[Elybazza61]

fossyant beat me to it

 

[Gillstay]

Yep. buy the biggest bike he can fit on now and so future proof it a bit. Some S/H Isla bikes around at reasonable money and before they get too battered.

 

[Reynard]

Yeah, well if you look around, bargains can be had. I picked up a Specialized Hotrock at the local tip (Witchford) for £35. All it wanted was a good clean and service, and a saddle that was kinder to my bum, to make it perfectly rideable. And I've enjoyed many a ride already*.

There is an issue with the cables (they're fraying / been cut where they shouldn't have been), and I want rid of the twist shifters (they're OK, but I prefer triggers), so I've got the parts to do the task. That's on the agenda when I've got spare time. But right now, I'm OK with the bike the way it is.

So £35 for the bike, £20 for the saddle, bought from someone on the forum, £5 for a pair of trigger & brake pods off the 'bay, and I think it was less than a tenner for a complete set of gear & brake cables from my LBS.

* I should add that I'm female and 4ft 11, so ride junior bikes.