I don't recall it hurting.

I bonked doing two laps of Cwncarn at race pace when I was scouting the course for the next days race. got back, stuffed my face, felt ill, proceed to come 72nd compared to the previous years 17th!!
not a good plan!

i don't think its ever hurt either. My most memorable 'empty tank' followed a 5 hour winter ride a couple of years back. I was utterly spent after the first hour of churning through ridiculous amounts of mud but kept pressing on anyway. I got to the highest point of the ride around 12 miles from home and just stopped the bike and sat on the floor. Luckily a mate had a couple of energy gels and a flapjack that perked my up enough to ride like a maniac for 30 minutes until the effects started to wear off and the bonk returned with a vengance. I rolled the last 8 or so miles home at a snails pace and ate 2 roast dinners before collapsing onto the sofa and sleeping fitfully for the rest of the afternoon.

You can bonk four times before your body says STOP. I used to go Bonk training where you ride between bonk 2 and 3.

My worst was after doing the infamous "silly circuit" in the Peak. Finally made it to Bamford station to get the train to Sheffield (then Derby). There was a minging half-empty bottle of Lucozade sport rolling around on the floor of the train and the whole train ride was total mental torture, trying to convince myself that I REALLY didn't want to drink it. McDonalds (at Sheffield station) has never been so good.

Pretty much as everyone has explained already.

Can only remember bonking twice, by far the worst of which was in Cornwall during the 2003 heatwave. Hit the wall about 10 miles from the B&B and felt so bad I had to push the bike for a bit. Thankfully found a garage where I refuelled but I only felt marginally better. Felt absolutely horrible; dizzy, nauseus, hot/cold, weak, feverish, unable to think properly, etc. Spent the rest of the day recovering. May well have had some kind of heatstroke/exhaustion as well. Either way, it's not something you want to experience.

What made it worse was I dropped my Oakleys in a field (during the walking phase) and had to retrace my steps the next morning. Found them in the end.

This is the one thing that stops me riding for longer. I get the shakes feeling. Putting concentrated cordial into your camelbak really does help then?

Actually I have had it since.
I did the SDW a few weeks after getting my first MTB. I know it gets done there and back now, but back then it caught me out. I had a bit of food and a water bottle and a 35litre back pack on, plus it was blisteringly hot. And I got lost.
Anyway got to the end not in pain but feeling like I'd just come out of general anaesthetic.
When I tried to eat my food hiccuped up, not vommit but it wouldn't go down. It was very worrying. Finally I swallowed some tined peaches, but it lasted a good day.

just stopped the bike and sat on the floor

Yep, that's exactly what it was like for me when it first kicked in. **** horrible.

Might pop abit of this in the camelbak this weekend:
http://www.hollandandbarrett.com/pages/product_detail.asp?pid=550&prodid=631

Had it on the Dyfi enduro this year with 10-12 km to go :(. Completely horrendous hollow feeling (stomach felt like it was a good metre square in size), legs were also cramping. Rode in survival mode looking at floor and spinning cranks slowly for some reason energy gels weren't working and I did not feel like eating. My own fault for going for the first 20 miles too fast I guess. Got to the feedstation in 45th place and ended up finishing 109th, but not a pleasant experience at all. By the finish line In Mach I could hardly talk my voice was that husky :(.

Hora. You never have to worry about bonking.

On the Last Peaks Pootle at the top of Cavedale I became very shaky and weak. How long was that sodding ride? 6hours?????? 😆

RHS, have we ridden together dude?

'I became very shaky and weak'

Well done.

Only time it's happened to me was at the end of a 3 hour ride on the road bike – intended to be out for an hour, got lost, found some nice roads – did some hills, eventually made my way home and got hammered approx 5 miles out – no money for snacks and just water – ugh, the spin of shame with old ladies overtaking me on their shopping bikes. Always have a few quid on me now just in case.

I can now tell if I need to eat more on long rides because of rising feelings of dread – if the ghosties are coming, eat cakes!

What is bonking?

I've become faint on rides quite alot i.e. the Bonk is in the post!

But my most recent full on bonk was due to eating rubbish the night before then doing a hard training ride out on the moors in the pooring rain, felt it coming on whilst 10miles out from home. Rode back slip streaming a fellow rider. Got home and literally inhaled numerous packets of crisps, coke and chocolate, wife came home, walked into the dark front room seeing me white as a ghost surrounded by empty packets of food soaking wet shaking… must have been quite a comical sight!

When I tried to eat my food hiccuped up, not vommit but it wouldn't go down. It was very worrying. Finally I swallowed some tined peaches, but it lasted a good day.

They do say that if your feeling unwell and unable to eat, nothing slides down as easy as tinned peaches.
And, if you continue to feel unwell, nothing slides back up quite as easily as tinned peaches either.

Just been talking to my mate, and yes he did get so bad he started to eat grass. He must have been 14 I was 16 and had been out with Kenton RC and their roadmen group. He also got proper aggitated and started to swear at everyone.
Happy days.

It's not just when you start burning fat. My physiology's not good enough to explain better, but you burn plenty of fat in any old long ride, without getting into mischief. Bonk is more mischievous 🙂

Putting concentrated cordial into your camelbak really does help then?

I used to use a mix of half juice and a bit of salt. I've now got pretty lazy and tend to use those sports powders, and with just that (and having eaten a decent breakfast) I can normally ride on my roadbike about 4 hours or so, with maybe a muesli bar or banana. Here you can buy the powders in tablet form which is great for multi-day tours.

Most recent near-bonk experience was being clobbered by the man with the hammer just under two thirds of the way into a sportive. Unfortunately, that sportive was this year's Tour of Flanders, and just under two thirds equates to 100 miles. I had another 63 miles to ride and 15 of Belgium's most famous bergs to grovel over. 😯

That was a long day out on the bike (and serves me right for not eating enough breakfast and working too hard for the first 85 miles).

Embrace the bonk..! 😀

Hora, that conversation we had when you were bonked off your tits still makes me chuckle..

Location: centre of castleton
Hora "we're just going to go straight back to Edale I think"
Me "So are we"
H "which way is it"
Me "over that hill" points at Mam Tor
H "oh"

😀

I know when I'm coming close to the bonk when I get all giggly, staggery if we stop riding and start slurring my speech. The early stages for me are a lot like being drunk. I remember being out with our club and stuffing down half an energy bar that my pal had given me and nearly choking because I couldn't stop giggling. The others were failing to see the joke…

I know. I was gutted. For some wierd reason my concept of Geography went amiss. 😆

slowriders sticky cookie at the bottom of Cavedale saved me

I feel 'confused and fragile' best describes my bonk. On Mam Tor old road I just wanted to be left where ever I fell and I'd die there peacefully.

oldgit – Member

Some of the guys rode off and came back with Mars bars

'keep a Mars Bar in your pocket incase you feel the knock' was one of the best bits of advice my Dad gave me when I started riding properly!

Got myself a bit lost and was pushing it a bit too hard one day when I was about 14, had to stop in the middle of nowhere completely burnt out, head spinning and jelly legs, felt like I was going to pass out, just stumbled on to me arse and sat there for what seemed like hours with my head in my hands til I got the strength to eat.

Never left it too late since!

so does anybody know exactly what it is, from a scientifc point of view?
everyone seems unsure??
what the definate cause or prevention?

it's hypoglycemia – basically low blood sugar levels.

http://en.wikipedia.org/wiki/Hypoglycemia

The reason most cyclists feel so bad when they get it is because it's usually coupled with exhaustion.

I found the mental side way worse than the physical. Was only about a mile from home but really felt i wasn't going to make it. Started to feel a bit hysterical. Got home threw the bike into the lounge and just couldnt eat rasberry jam sandwiches fast enough. After 20 mins started to feel better but not a nice feeling.

It's happened to me twice in 20 years.
First time I was riding home from Leicester back to Chesterfield the morning after a big night out. Hadn't eaten properly and went bang just north of Derby. Got myself to a garage and grabbed acouple of bottles of coke (I think) and some other junk. Ate half of it in the queue to pay and just dumped the empty wrappers on the counter. Ate the other half outside and crawled the rest of the way home.
2nd time was a few years later on a long road ride. Luckily it was just before home and I got back ok. First thing I laid my hands on was a tub of Isostar powder so sat and ate it with a spoon, washing it down with water. Yum!

First thing I laid my hands on was a tub of Isostar powder so sat and ate it with a spoon, washing it down with water

Brilliant!

Never touched it since 😆

Kendal Mint Cake is the old fave,used to carry that with me in my younger days,my old man used to swear by it..

Aye Blower, its got LOADS of sugar in thats why, a great back up and also yummy 🙂

Forgot about Kendal mint cake, great stuff unless you got it wet?
Brought back memories this post.
Steel road bikes, clothing was leather and wool, no mobiles, shops were shut Sundays and garages didn't sell food. You were on your own.

only bonked properly once although have ben on the edges several times.

i went for a ride once with the intention of bonking to find the warning signs (not fun!!)

I tend to keep a go bar in the bottom of my camel back for these moments.

go bars are best for 2 reasons; the have the most indestructable wrappers & they taste rank (which means you never eat them some other time!!)

i looked it up properly before. Its way more than low blood sugar but your body forcing you to slow down to an intensity that it can convert energy from a source. That source becomes muscle protein or something like that. The figure was around 300 cals an hour. So basically not enough energy from all normal sources = empty tank = body goes to survival mode to make organs + brain get energy to work thus the hammer comes down. There was a posh wprd that had something to do with liver processing energy.

Oldgit- proper chamois in yer shorts,leather saddles…

rhsno2- go bars are nice i think..

must stock up on kendal mint cake again mithinks!

Only properly bonked once, thank heavens. In Portugal on a touring/ATB solo trip (I carried nobblies to swap from my touring slicks) waaay ago in 1988! Three hours uphill on a small breakfast and a fully loaded bike, crawled to a cantina for fizzy pop and a baguette.

Never, ever, again!

Only had the bonk once on a merida marathon. I could not believe how awful I felt. Never again. I always carry spare gels just in case. That's because I ate so much junk when I got back I had spots for a week and felt very, very sick for 4 days.