Rider Weight and Lightweight Bikes/ Components....

Grisley Paul

I'm sure this has been discussed before but I was wondering in this modern era of everything being super light, do manufacturers actually ''stress'' their components up to a certain rider weight etc ?

I've only recently got into road cycling from MTB and have bought what it basically a winter training spec machine i.e. Shimano RS20 wheels, carbon forks with alloys steerer etc..... I weigh dead on 14st at 6ft tall and was thinking sometime down the line I may wish to invest in a much better spec and lighter machine but then I had concerns about being too heavy for this super light stuff.....

As we all know the UK roads aren't always exactly the best either, presumably there has to be an upper limit as to what rider weight and loads through a frame/ wheels etc they'll tolerate before something nasty happens ?

Monty Dog

The only areas where you need to consider rider weight are when you get into uber-light weight-weenie stuff, particularly wheels. Most mainstream bikes and parts should cope with 90-100kg.

Grisley Paul

Just watched a youtube vid on the Cervelo R5 California........ circa 10lbs all up weight.... :shock:

Stick a 250lb guy on that and surely something will give

dw300

You planning on taking it off any sweet jumps?

unixnerd

Save the upgrades until spring and train hard over the winter, the weight will fall off! :twisted:

Grisley Paul

unixnerd wrote:

Save the upgrades until spring and train hard over the winter, the weight will fall off! :twisted:

I'm a plumber/ bathroom fitter by trade, I do physical work all week long AND cycle when I get the chance, I'm still gonna be a 14st guy (maybe 13st if I were to go crazy on the nutrition side of things) but I still have a life to lead....

I enjoy my cycling at my weight for the health reasons, but like most it's easy to get carried away and seduced into the world of uber bling and lightweight equipment, so I am just interested as to whether this lightweight exotica would be able to deal with my mass, if in time, I choose to go down the ''bling, lightweight, look at me''... route with regards to components.....

priory

Since I started buying aluminium frames 14 years ago I have broken 3 . That is all but one of them. since 1980 I have had steel 6 frames. One got dented in the shaft of the down tube and cracked there 4 years later . The others had no problems. One 30year old is my usual hack now.
I have ordered a dawes century (steel frame)to replace the latest casualty,At the moment I am not in the mood to contemplate light bikes again.
Steel frames are usually stiffer at the bb . Except for my 62cm 531 frame , which is a bit bendy in the hairpins, they can be stiffer all round.
I weigh about 90kg usually. riders of 60kg have different concerns.I think I might as well have 1 or 2kg extra on the bike if it is stiffer and doesn't break and I can use trails and hit potholes without smashing the bike.

the second part of this film shows what happens if you hit a dog at slow pace with an over-expensive racing wheel.
http://www.bing.com/videos/search?q=you ... B9&first=0

Grisley Paul

priory wrote:

Since I started buying aluminium frames 14 years ago I have broken 3 . That is all but one of them. Meanwhile I have had steel 6 frames. One got dented in the shaft of the down tube and cracked there 4 years later . The others had no problems. One 30year old is my usual hack now.
I have ordered a dawes century (steel frame)to replace the latest casualty,At the moment I am not in the mood to contemplate light bikes again.
Steel frames are usually stiffer at the bb . Except for my 62cm 531 frame , which is a bit bendy in the hairpins, they can be stiffer all round.
I weigh about 90kg usually. riders of 60kg have different concerns.I think I might as well have 1 or 2kg extra on the bike if it is stiffer and doesn't break and I can use trails and hit potholes without smashing the bike.

the second part of this film shows what happens if you hit a dog at slow pace with an over-expensive racing wheel.
http://www.bing.com/videos/search?q=you ... B9&first=0

Interesting info.... many thanks

Blimey that last bit of footage with the dog is mad, that wheel just buckles like it's made of cardboard :shock:

My current (and only) road bike is an Alan and weighs in at 19lbs with carbon fork, carbon seat and chain stays and alloy frame with a modest wheelset, I think that's as light as I'm gonna go for my weight right now

TakeTurns

I'm 6'5 and weigh just under 14 stone. I've ridden both high and low spec bikes. The only issue I've had is the wheels. Unless you buy a decent pair of strong, well tensioned wheels, you're screwed. I've even had trouble with hub-bodies breaking. Everything else on the bike however will be fine.

My 'high spec' bike was a little under £2k. The wheels on it weren't great, horrible in fact. Always went out of true and flexed when I'd get out the saddle on hills. 2 months in I got rid of them and upgraded to deep section carbon wheels. Dura-ace c50 to be precise. These wheels are bombproof, had them for 4months now and still in perfect true.

The point is, even bikes with high specs tend to have crappy wheels. Having worked at Evans Cycles, unless you buy a bike £2k upwards, the wheels will not live up to the quality of the other components.

farrina

priory wrote:

the second part of this film shows what happens if you hit a dog at slow pace with an over-expensive racing wheel.
http://www.bing.com/videos/search?q=you ... B9&first=0

If you study the video closely (whilst not a recommendation for lightweight wheels) just before the impact the wheel twists slightly to the right so the force of the impact is more across the wheel where it is at its weakest rather than in line with the rim where it should (I believe) be at its strongest.

Turning to frames, having always ridden Reynolds tubing, I must confess myself somewhat uncomfortable with carbon and the likes because of their perceived tendency when they break they tend to break catastrophically. There is always that nagging doubt after a spill whether you might have caused some unseen damage.

My experience of Reynolds is that they degrade gracefully ie crack and don't fail without warning.

Visually I prefer the look of the new carbon frames to mine, but I am not comfortable with their integrity.

Ditto wheels - call me old fashioned (perhaps I am) but I prefer 36 spokes on the back and 32 on the front.

Just my ten penny worth.

Regards

Alan

ps Height 6-4 and 176 lb

napoleond

I was riding my light Cervelo R3 (sub 1kg frame) at 100kg with Mavic Ksyrium Elites and a 27.2 carbon seatpost and never had an issue.
However at 88kg and dropping my bike seems to be getting a lot faster.

Monty Dog

For those with a concern regarding the robustness of carbon frames, search Youtube for "Cannondale Taurine vs Hammer". Alloy and vitrually all steel frames would never withstand that level of abuse. For those who grew-up riding steel frames, there was almost a ritual every winter where someones bike would fail due to corrosion. The vast majority of bike failures these days are due to crash damage rather than inherent inability to take the stresses of riding.
In terms of the OPs questions, 14st isn't that heavy these days and provided you are sensible with component choices you should have few worries - Videos of £2k Lightweight wheels folding under impact is not symptomatic of normal bike components.

farrina

Monty Dog wrote:

The vast majority of bike failures these days are due to crash damage rather than inherent inability to take the stresses of riding.

I guess that's my issue - if you have a crash with a steel frame its pretty obvious if there is a problem (and this can be resolved relativley cheaply albeit at the cost of a respray). With carbon, I would be worrying over marks on the frame wondering if they were just superficial or more deep seated, and this would affect my confidence in the frame.

I suppose it might be possible to have some form of scanning of the frame post incident, but can't see this being widespread as the Pro's if there is the slightest doubt will just get a new frame.

I don't expect modern carbon frames are likely to just fail without cause (although I have seen some nice pictures on these forums of peoples whose carbon frames appear to have just done precisely that!) or at least they always say its not been crashed - this could just be for warranty purposes of course ....

Corrosion can be an issue with steel but this can be caused by inadequate maintenance - I am still happily riding one of my 531c frames that is 25 years old, which funnily enough did have a problem with the down tube fatiguing at the headset thought to be because of a dodgy braze, albeit it did manifest itself for 12 years (since repaired) but it still got me home.

I may be wrong but I would suspect that replacing or repairing a carbon frame is going to cost considerably more than steel (not talking Titanium or Aluminium here).

I suppose the ideal solution would be a new carbon frame after every siginificant spill or as a matter of routine every (say) 5 years, but given their price this would only be a solution for those with deep pockets.

Visually I prefer carbon (especially the broad fork blades), but every time I rattle down a bumpy 40/50mph decent my desire seems to ebb away.

(Tongue in cheek) Bet you are not riding your carbon frame in 25 years time

Regards

Alan

unixnerd

Bet you are not riding your carbon frame in 25 years time

Well mine has a lifetime warranty so you never know!

declan1

To answer your question OP:

http://www.youtube.com/watch?feature=pl ... ZmJtYaUTa0

Grisley Paul

declan1 wrote:

To answer your question OP:

http://www.youtube.com/watch?feature=pl ... ZmJtYaUTa0

Classic, love it...... well there you go, and he wasn't a stick thin whaffe of a guy either, quite well built.....

morstar

declan1 wrote:

To answer your question OP:

http://www.youtube.com/watch?feature=pl ... ZmJtYaUTa0

Fan, fookin, tastic. Thanks for posting. Absolutely love these videos.