Young Tod has really got into the swing of things with his long term test Trek Fuel EX Jr and it would seem his daddy (UK Editor) Jim, has enjoyed tricking it out and getting carried away with upgrades! The Trek Fuel EX Jr is already the ultimate kids enduro bike so what would Jim change for his little ripper?

Trek Fuel EX Jr standing in the snow

There is no doubting the Trek Fuel EX Jr is the badest of bikes out there when it comes to the little shredders. It oozes quality and style, replicating its larger adult Fuel EX big brother. The same Trek quality build has gone into the welds, the bearings, the linkage and the look. But the first thing that was noticeable was the weight at 13kg this had to be brought down to a much lighter weight for someone who ⅓ the weight of your average male rider!

Jim and Tod on a winter ride

At first we thought we had to be realistic with the upgrades and not go out and out bling crazy! The likes of Enve wheels and XX1 cranks were out of the question, as realistically the average parent will not be willing to spend the budget on these for their kid. So for the upgrades we tried to look at a budget in the middle of the road when it came to the price bracket, to make things more affordable. As always, though, once Jim got into the rhythm of upgrading, he saw the red mist and got carried away! Most of the build considerations (except maybe a couple!) were made with performance and simplicity in mind, so this is what we did.

Invisi Frame protectors on the Trek Fuel EX Jr New grips and breaks for the Trek Fuel EX Jr

As you may have read in the First Look and First Ride articles we already sent it to Invisiframe from new, for those much needed laminated stickers for €94.80 offering protection from the inevitable droppages! The Rockguardz carbon fender for €60.78 has also been on it from the word go, keeping the shite out of the lad’s eyes. Originally this bike came with a two-by-ten setup. With Tod never having used a front mech and also for simplicity we ditched the front mech and shifter to favour a 30-tooth thick/thin single chainring, supplied by the UK company Uberbike Components for €34.99. Uberbike also supplied a 42 tooth expander ring for €46.19, so Tod still had the wider range of gears for his little legs to spin him up the hill. The chain is also kept planted upon the chainring by MRP’s (not so budget!) 1X carbon chain guide for €138.99.

New XT cranks on Tods Trek Fuel EX Jr 42 tooth expander for the rear

The cockpit of the Trek Fuel EX Jr was the next to get a makeover, the short 585mm alloy bars with their longish 65mm stem were replaced with a 35mm Nukeproof Zero stem €64.99 and Nukeproof’s carbon Warhead bars (€129.99), which were cut as short as they could go, down to 650mm. With this set-up we had dropped cockpit weight, given Tod a wider (but not too wide) grip plus the bike now had a shorter and more controlled feel. Talking of grip, this bike came equipped with some adult-sized grips, far too big for junior fingers, so we opted for the new Fabric grips €25.99, they are as narrow as grips can be and real sticky, these things were perfect. The brakes were up next, originally fitted with Shimano’s cheapest and heaviest unbranded version, they worked well enough, but the levers were huge and the system the heaviest of all the Shimano disc brakes. These were replaced with the fantastic, lightweight, two fingers levered SLX version is €197.99. Shimano also helped out when it came to the cranks, the original ones also were unbranded, 160mm and as heavy as some entire bikes! It was a real struggle to find some different 160mm cranks without spending mega-bucks, so we compromised and went for 170mm with the ever popular Shimano XT versions for €131.99.

Nukeprook bars and stem on Tods Trek Fuel EX Jr Closeup shot of the breaks

Next up was the biggy, the thing we knew would make the most difference and cost the most money of all the upgrades; the wheels. They had to be light weight, strength was not really an issue, with such a lightweight rider, but we also knew the upgrade from tubes to tubeless would get the weight down some more. The toughest thing about this decision was not the cost really, more the fact that the bike has 26” wheels; these quickly becoming a thing of the past! Fortunately, Stans were on it with the solution, they sent over a set of their Crest wheelsets, used for XC racing. These are very light for an alloy rim at 1440g, tubeless and of course, come in at 26” as well as what is now considered the normal 27½”, and let’s not forget they look seriously trick too for €593.99. So the heavy wheels were removed with their summer tyres and tubes, then the Crests were fitted with their beautiful Ti hubs. Of course, these had to have some fresh rubber adorned, so we chose one of our favourite all-around tyres and one much more suited for grip in the UK winter too, the Maxxis High Roller II for €73.99. Stans also took care of valves, fluid and tape for €57.99; now the bike was looking seriously sharp!

Stans No Tubes ZTR Crest wheelset

It was nearly done, just one final piece of the puzzle had to be sorted, to make the Trek Fuel EX Jr become a full-on junior enduro machine which any full-sized rider would be proud of. The Fuel EX Jr came fitted with an ordinary (dare we now call it) old fashioned seat post. We thought a bit about whether a kid needed a dropper post at aged nine, but when you think they can drop it out of the way for extra confidence down the steeper stuff, then surely it is a worthy upgrade for increasing their skills at a faster pace. With the frame being tiny, especially in the seat tube department, we had to do our homework on this one, the dropper couldn’t have a long outer body (the bit that fits into the frame) and the necessary drop needed for his kids legs was estimated at 100mm. It was KS to the rescue here with their version for €355.99, this is a nice simple cable operation post, with one of the softest pushes needed to operate it. As a little bonus, we were sent the lighter weight, smaller and very trick looking Pro Vulture saddle for €104.99 to sit upon the top of the KS.

New saddle for the Trek Fuel EX Jr 100mm KS dropper post

So that was it was finished like we said Jim may have got a tad carried away, more than doubling the price of the bike, with a total spend of €2150.61 on parts alone to lose a total of ½ kg and bring it down to 12.5kg. Ok, so we can’t imagine your average biking parent would spend that much in one big hit on their little nipper’s machine, more like replacing parts as they wear out, or upgrading certain things as birthdays and Christmas’ came along. But we think this is now an awesome little machine and one any kid would be exceptionally proud of; as is Tod. Now we also realise that a kid’s bike only has a short shelf life, as kids grow quickly. But with this bike being pretty long and having 26” wheels, we think a kid could get a good few years out of it before it became too cramped and by then this bike is loaded with nice components to swap over to its upgrade.

Tod is super happy about his pimped up Trek Fuel EX Jr
The Trek Fuel EX Jr weighs in at 12.51 kg after the upgrades

He is absolutely loving the Trek Fuel EX Jr now, as he gets to grips with it, learns to get the wheels of the ground and is starting to hit the downhills with some more adult paced speed. Also, the difference in his leg power when it comes to taking him up the hills is vastly increasing upon every weekend’s winter ride. Watch this space for the fourth and final verdict on the bike, exactly how Tod has got on with the bike and what, if anything needed to be fixed or serviced; as so far, four months down the road, nothing has needed attention on the frame or suspension.

Interested in Bikes for little shredders? Read our Kids-Bike Comparison.

More Information on the Trek Fuel EX Jr can be found on the Trek-Website

Words: Jim Buchanan Photos: Isac Paddock, Jim Buchanan

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