What size allen key fits the crank?

[Ajax Bay]

the crank had come loose. I only carry Allen keys that fit things on my bike, and they are small sizes. . . . what size(s) I need to carry for cycle cranks.

@night cycler What size allen key would you need if your crank came loose? Several different makes/systems of crank: you need to specify which one 'Maid Marian' is going to be riding. Are you carrying a chain tool and spare quick links like Skolly? And a spoke key? Both more likely to be used. Your wish to be able to help others suggests your best bet is a multi tool. Personally I, maybe like you, prefer to carry individual keys, and only the ones I might need.

 

[PMarkey]

I have a Topeak multi tool with an 8mm adaptor that slips onto the 6mm key but as my Longstaff trike uses crank bolts to hold the wheels on I also carry a full size 8mm Allen key as the multi tool flexes a bit to much .

 

[ebikeerwidnes]

If you start carrying everything you might possibly need you will need a cargo bike to carry it all

no point in carrying an extra pound up a hill every day for a year in the vain hope that a damsel in distress will need an 8mm allen key or a quick link replacing

I carry enough tofix the most common problems with my bike and that's it - if that allows me to fix someone else's problem then that's great

e.g. I have 2 spare inner tube- but I only carry the one that is relevant to the bike I am using - if someone need one I will let them have it

 

[Sharky]

It's strange thinking back to days gone by. We all used to ride tubs, so only used to carry one or two spare tubs. No need to carry any tools or repair kits as wheels were all QR. Fixed gear riders would carry a 1/2 :9/16th spanner, but that's about it.

Look in my small bag now and I've got repair kits, tubes, chain splitters, levers, Allen keys, small adjustable.

Has technology got less reliable or are we getting over cautious?

 

[DCBassman]

Has technology got less reliable or are we getting over cautious?

Once upon a time there was backup, otherwise known as "Public Transport"...

 

[Alex321]

It's strange thinking back to days gone by. We all used to ride tubs, so only used to carry one or two spare tubs. No need to carry any tools or repair kits as wheels were all QR. Fixed gear riders would carry a 1/2 :9/16th spanner, but that's about it.

Look in my small bag now and I've got repair kits, tubes, chain splitters, levers, Allen keys, small adjustable.

Has technology got less reliable or are we getting over cautious?

I think your "we all" is in fact a very small subset of the cycling population.

I don't think it has ever been common for anybody outside the serious(ish) racing community to use tubs. And as a teenager (over 40 years ago now), I always used to carry a puncture repair kit and tyre levers (and a pump which was most of the length of the top tube, held by two brazed on "points"). And one of those "dumbbell" bike spanners, which was needed to get the wheel on or off, but also fitted various other bits. I don't think QR wheels were available for regular cyclists back then.
I don't recall carrying a chain tool then, but I had a 5 gear bike (10 were for racers or rich show-offs), so a pretty thick and robust chain. I only started carrying a spare tube when I started commuting by bike regularly in the 80's, and realised it was much quicker to just swap the tube out and repair it when I got home.

 

[Cycleops]

Still got and use one of those old dog bone spanners.

 

[fossyant]

Plenty of commuter cyclists who don't even carry spare tubes. Not a big issue for a short commute !

 

[Alex321]

Plenty of commuter cyclists who don't even carry spare tubes. Not a big issue for a short commute !

True, but mine then was 14 miles each way. Much quicker to repair it than push the bike to destination, quicker still to swap the tube. If it had been a 5 mile commute, I probably wouldn't have bothered.

 

[ColinJ]

I got one of those last year and luckily I've not had to use while out yet but it seems a quality bit of kit.

I've had one for years, and have used it to rescue several riders who did NOT have the tools to sort their own bikes out!

One example...

I acted the Good Samaritan yesterday at the top of the Nick o'Pendle. I'd winched my way up there and decided to stop at the summit to stretch my back and enjoy the view. After a couple of minutes, a chap (later found to be named Jim) came over the brow of the hill pushing his bike and holding what looked like a dead black snake coiled round a stick. In a slightly forlorn voice, he asked "Can you do anything with this?" Why did he think I needed a dead snake? As he got closer, I saw that it was in fact a dead oily chain. This was a job for Bicycle Repair Man! Since BRM wasn't available, I decided to volunteer my services instead...

I'd practiced using my chain splitter recently when shortening a new chain for my Basso. I put my newfound skills to good use and had soon taken out the broken link.

It wasn't long before Jim's bike was ready to ride again and we set off on the descent together. Even though the sun was shining, it was really nippy on that side of the hill, dropping down into a cold wind.

We stayed together for the rest of the ride and it was nice to have some company for a change. I usually tend to ride alone on audaxes because I'm slower than most, but slightly quicker than the slowest.

Jim insisted on paying for my cake, Coke and water at the control cafe in Waddington. Later on we encountered a couple of his mates and joined up with them for the ride round to Coldwell.

PS I bumped into Jim on the same event the following year. I said that I hoped he was carrying some tools this time. He smiled and fished out an identical Crank Bros tool to mine!

 

[Mark pallister]

I was on the canal recently, and coming towards me was a bloke pushing his bike. On enquiring what the problem was, he explained that the crank had come loose. I only carry Allen keys that fit things on my bike, and they are small sizes.

It kind of dissapointed me that I was unable to help due to the absence of a specific size key. I have plenty of keys at home, and for how little they weigh it won't matter to carry 2 or 3 larger sizes. So, can anyone tell me what size(s) I need to carry for cycle cranks. For so little effort on my part It can potentially save someone a long walk. I cycle that route two or three times per week.

5 mm for hollow tech

 

[Mark pallister]

It's strange thinking back to days gone by. We all used to ride tubs, so only used to carry one or two spare tubs. No need to carry any tools or repair kits as wheels were all QR. Fixed gear riders would carry a 1/2 :9/16th spanner, but that's about it.

Look in my small bag now and I've got repair kits, tubes, chain splitters, levers, Allen keys, small adjustable.

Has technology got less reliable or are we getting over cautious?

Over cautious I would say ,well maintained modern bikes are very reliable in my opinion

 

[si_c]

I have a Topeak multi tool with an 8mm adaptor that slips onto the 6mm key but as my Longstaff trike uses crank bolts to hold the wheels on I also carry a full size 8mm Allen key as the multi tool flexes a bit to much .

Yep, both my Topeak Hexus multi-tools have an 8mm adapter for the 5mm wrench which should work in a pinch. Of course I make sure that my cranks are done up properly in the first place