Disclaimer: Characters, situations, backstory etc all not mine, and this is not written for profit.

Sherlock gave a slightly deeper intake of breath that John now recognised as the starting point for one of the 'data dumps' of information he liked to share amongst those who questioned his deductions. Just what they needed right now! John folded his arms with a resigned sigh and stood back to watch.

"It's childishly simple, really," – the classic Sherlock beginning – "your left coat pocket displays the distinctive outline of a pair of folding bolt cutters, used to snip through inadequate bicycle cable locks. It's too big to be a standard multi-tool or pen-knife, but small enough to conceal about your person. That's highly suggestive but not conclusive." The teenager unconsciously shoved his hand in the pocket to disguise the bulge, but Sherlock had moved on. "From your rear jeans pocket protrudes a pair of hastily stashed disposable latex gloves, to ensure you don't leave fingerprints at the scene. Maybe you just happened to have them for fixing or cleaning your bike, but combined with the bolt cutters that just screams experienced thief." John silently willed him to dial back on the condescension. "Then you also have a cheap navy blue polo shirt stuffed into the plastic bag dangling from your handlebars, on which there is a 'Burger Jam' nametag reading Darren Jones. A teenage employee of such an establishment, receiving the reduced rate of national minimum wage, is very unlikely to splash out on a custom-built £1500 carbon fibre road bike for cycling idly around the streets of Brixton. Plus the bike is clearly set-up for someone around my height while you're barely five foot eight, which is why you're so uncomfortable standing there with that crossbar digging into your crotch. Is that sufficient for you?"

"Are you with the police or what?" the youth scowled, defensively grabbing for the bag containing the incriminating nametaged shirt and stuffing it inside his half-zipped coat. He kept a tight grip on the bike, and John remained unconvinced that this pavement showdown was going to end well. When did accosting a teenager cycling on the pavement ever end well for anyone?

"I'm not with the police but I am commandeering this stolen bicycle for the purpose of justice," Sherlock declared with his mid-case customary manic enthusiasm and a perfectly straight face, leading John to wonder if he was about to tear open his coat and reveal a red and blue costume with a big S on the front. The teenager – Darren, seemingly – looked like he might be having similar thoughts, all concluding with 'who is this freak'.

"I told you I didn't lift it, I only found it! It was in a skip, someone must've decided to chuck it out. What you said was all bull, man." The bravado did little to hide the angry confusion at Sherlock's spiel, and sensing a lost cause the youth swung his leg over the bike and let it fall to the pavement with a clatter. "But I don't need this hassle – just take it."

"Thank you kindly for your donation towards the greater good – maybe it will cancel out one or two of the shoplifting sprees you'll be helping with tomorrow morning in Oxford Street. The plan is to start at HMV, right?"

"How do you… look just fuck off, alright?" was the angry retort as the teenager quickly stalked off down the street, throwing a worried scowl at the pair of them and dialling someone on his phone.

"That last bit was a lucky guess," Sherlock admitted as he picked up the fallen bike. "But a large proportion of Metropolitan case files on shoplifting involve Oxford Street, and what teenage boy can resist console games and DVDs? Now female teenage shoplifters, they're quite different…"

John interrupted him with a shushing motion. "Hang on, is antagonising possibly armed, possibly gang-member, definitely bike-thieving teenagers a wise move, Sherlock?" He was wondering who the kid might be calling and whether they were bigger, 'tooled-up' as he believed the phrase was, and going to come along and have a chat about who had the right to do what with stolen goods in this neighbourhood.

"We don't have time for boring niceties, John," Sherlock chided as he somewhat awkwardly mounted the bike. "We've got the final piece now, but we've also got less than thirty minutes to get to the Serpentine and stop the meeting between Briggs and the undercover journalist, or the last week of planning is all for nothing! The tube strike and resulting completely stationary traffic mean it's this or you magic up one of your old army helicopters."

"But there's still only one bike…" John pointed out with a dawning realisation. "Hang on! You are not going on your own. The man's a lunatic! He's arranged the deaths of three people – that we know of – and you're going to rather piss him off by ruining his chance to escape scot free with all that cash and a one-way ticket to the Bahamas, so I don't think it's unreasonable to at least call Lestrade and have him waiting in the wings as back up." He paused. "Do that thing again with another bike-thieving hoodied youth and get me a bike too. Or maybe a scooter or something else that has an engine…"

"There's no time, John!"

He could see his friend's single-bloody-mindedness was rearing its ugly head again; this was going to end with him being left behind by himself in Brixton. He really didn't want to be left behind by himself in Brixton. Particularly if Darren was going to come back with some friends.

"Sherlock…" he cautioned in the low, warning tone of voice widely recommended by dog trainers for exerting authority over wayward pets, and more specifically recommended by Mycroft for exerting authority over a wayward case-hungry Sherlock.

"Catch up with me when you can, I've got a case to solve!" Sherlock shouted, his mind fixated on puzzle-solving justice. He pushed off firmly and managed about half a revolution of the pedals before wobbling to a standstill and crashing over onto the pavement with a dull thunk.

"You could have mentioned – before suggesting the bike-commandeering plan – that you can't actually ride a bike."

John lifted the handkerchief makeshift-bandage away from Sherlock's head to see if the gash had stopped bleeding yet. It hadn't, so he applied pressure once more to a protesting 'oww'.

"I didn't think that was relevant information," Sherlock grumbled. "I've seen people ride bikes on numerous occasions, I assumed I would have absorbed the knowledge by now…"

He sounded less than enthused by the way things had turned out – once John had quickly established from the swearing tangle of limbs and bike that his friend hadn't killed himself in a two-mile-an-hour cycling crash, he temporarily left doctor-mode to call Lestrade and filled him in on the developments in the case. If it all had gone to plan, the arrests were about to be made. With Sherlock on the opposite side of the city. As far out of the loop as he could get.

Sherlock was Not Happy with this.

The offending bicycle was now propped up against a wall while Sherlock sat at the edge of the kerb, sulking as he picked at a tear in his coat. John tutted as he searched his pockets for anything else sanitary enough to be used as a temporary bandage.

"You can't just learn to ride a bike by watching someone else, you need to practice, it's muscle memory, like your precious violin. And who can't ride a bike, anyway?" He fished out a couple of spare coffee shop napkins. "Didn't you learn when you were a kid? Like normal people do?"

"I never had a bike; my parents seemed to think I got in enough scrapes without adding further velocity and mobility to my inherent attributes." John felt a momentary pang of sympathy for the bike-less young Sherlock, tempered with empathy for what his poor parents must have endured. "I borrowed Mycroft's once," Sherlock continued, "he brought a vintage tourer back from his first term at Oxford. He wasn't too pleased at having to fish it out from the pond – it turned out the ice wasn't quite strong enough to ice-cycle on. It wasn't strong enough for fatty either – he got rather wet feet…" the memory received a low, satisfied chuckle.

"Such a delightful child," John commented, peering again at the gash. It looked deep and long enough to need a couple of stitches or at least gluing.

His heart sank a little further at the thought of accompanying a grouchy Sherlock to a three-hour wait in an A&E department. That couldn't end well for either of them, or the unsuspecting hospital staff. The surgery was closer, and he wondered if the receptionists would let him pop in and borrow a few bits of equipment.

"Okay, up you get – that head wound needs looking at properly." John waved away Sherlock's tetchy protests before they could begin. "I'm not going to insist you go to A&E, but if we can get over to the surgery I want to at least wash it out thoroughly and see if glue will hold it."

"How marvellous, a field trip to Doctor Watson's place of business," Sherlock commented with obviously fake enthusiasm, allowing John to help him stand up, "maybe we'll bump into Sarah. It's always lovely to see the two of you dancing awkwardly around each other." His grip on John's wrist tightened. "Will you just please call Lestrade and see what's going on with the case?"

"I will," John promised, extricating his wrist with some difficulty and making sure Sherlock's confiscated phone was still safely in his pocket. "After your head is sorted out. What would it do to my medical reputation if I let the great Sherlock Holmes die from a minor injury like this? For all I can tell your precious brain matter might be seeping out of that tiny cut, and coffee napkins are not approved medical supplies." Lacking anything else, he offered Sherlock a handful of them. "Hold these firmly against your head, and let's find a taxi to sit in for an extortionately long trip to the surgery."

Sherlock reluctantly look the proffered napkins and held them against his head, muttering under his breath as he started in the direction of the closest main road. John wondered for a moment whether he should leave the bike, but he was reluctant to abandon it where Darren or his associates might come back for it. If he pushed it with them then they might pass a police officer he could hand it in to.

John stood on one pedal, scooting along to overtake Sherlock who had been disappearing quickly up the road. He turned back and gave his morose friend a grin.

"You know, if you think you can hang on then I could give you a backy?"

Ten minutes later an out-of-breath but exhilarated John came to a stop outside his practice, with a rigid Sherlock perched uncomfortably on the back of the bike still holding on to his jacket with a death-like grip.

"Sorry Sherlock, I forgot to mention it's pretty much downhill the entire way…"

Author's Note:

For anyone who was a little confused at the end there, a "backy" is where you give someone a lift on your bike with them sitting behind you on the saddle generally clinging onto your waist or clothing for dear life. It's something people normally grow out of doing once they leave primary school, and I wouldn't recommend two adults (particularly one with a head injury) trying it!

So this was a little on the random side. I just found myself wondering if, along with gaping holes in his knowledge about such things as the solar system, Sherlock might be strangely helpless at everyday tasks like riding a bike. It's something he might easily ignore in favour of devoting his time to learning more "relevant skills". Yes it's all quite silly, but it kept me amused and out of trouble for an evening while I put off actual work!

This silly site seems to crash everytime I try to reply to reviews, so can I just take a moment to thank everyone who commented on my last fic - you are all very kind and it's a lovely welcome to this fandom!