How much punishment ….

[ourclarioncall]

What would it take to damage /destroy the likes of a nomad?

I’m curious to know what it could withstand as I think I could be overly cautious for fear of it getting damaged

Where do bikes fail first ?

Not saying I would want to but could it handle being ridden off the kerb repeatedly and cope with a 5” drop and thump? What about if the bike was loaded up with weight ?

[Danneaux]

Speaking as a hobbyist framebuilder who started decades ago by salvaging tubes from damaged frames, the quickest way to truly destroy any frame is to a) run into a curb or parked car head-on or b) incur a massive dent in the unbutted center section of the top or down tubes. Airlines baggage handlers can do a lot of damage. My bike was once selected for a bomb-detection exercise somewhere between Schiphol Airport in the Netherlands and my final destination in Portland Oregon. The frame incurred scratched but survived, the wheels, saddle and some components did not as the bike was badly repacked and seemed to have been dropped. I had no recourse as the damage was caused by the TSA rather than the airlines. I did once see someone "pop a wheelie" on a loaded tourer...and then snap the steerer tube just above the fork crown from the impact of landing. I saw another MTB fail when the rider "cased" a landing off a 2m high loading dock. I would consider these last two examples gross abuse. A seized seatpost can make for some real problems, so be sure to remove and grease it periodically. Rust and powdercoat are a bad mix and can slowly ruin a frame as the rust tends to "tunnel" under the fused plastic coating. Touch up nicks and scratches once in awhile and you'll be fine.

Aside from that, I've found the Raven Tour I rode back and forth across Europe and my own Nomad were remarkably durable and have so far survived all my travels without damage or incident. I tend to "ride light" and am considerate of my equipment (it is expensive and who wants to be stranded by a breakage tens or hundreds of miles from assistance? Not me!), but I have ridden (gently and standing) off standard city curbs while fully loaded if there was no alternative or by accident when I misjudged a swale in a curb for the top of a curb cut/ramp and incurred no damage. I once entered a steep downhill bridge sidewalk via a curb cut at the top and assumed there was one at the bottom as I coasted down it at 32kmh. The sidewalk ended in a step that was about 25cm high and by the time I saw it, it was too late to do anything except carry my speed off it. I stood up to unweight the saddle and handlebars and bent elbows and knees to absorb shock. I landed fine continuing with no damage whatsoever to bike, wheels, racks or me.

On expeditions, I weigh 78kg and my Nomad weighs 20kg. Fully loaded with 26.5l/kg of water and lots of food, it has carried 36kg loads, so total all-up weight 78+20+36=134kg/295lbs. I ride it on heavily ballasted logging roads (see pics) with deep potholes or cross-country and...no problems. Of course, I do not ride with such a load habitually but do on occasion when I need to be away from stores for some time and am solo. If desert touring in summer, then I need about 8.3l of water/day, so this is about a 3-day supply intended to last between windmill-pumped cattle troughs.

Much of the credit goes to the tires used. If they are large in cross section and don't carry really high pressures (as with my 26 x 2.0 Schwalbe Duremes), they can absorb a lot of punishment and mute impacts before they reach the frame.

The Nomad has been designed and engineered to address common failure points. It uses oversize tubing and stout tube wall thicknesses. The rack mounts are 6mm instead of the usual 5mm and it is well made and inspected multiple times before delivery. Andy Blance has taken great care to make all Thorn's bikes reliable for the long haul and real-world use. I don't think you'd have much to worry about short of some egregious incident or gross carelessness.

Best,

Dan.

[ourclarioncall]

Thanks Dan , I love long detailed posts , appreciate you pouring out for me 👍

[ourclarioncall]

So I’m thinking , as a kid why did we seem to be able to punish our bikes fearlessly and bikes seem to be unphased

Maybe coz we were all on mountain bikes that were with or without suspension

What helps the most with impact , is the big fat mountain bike  tyres or the suspension or a combo of both

Saying that , typically most rear wheels had no suspension and would take a thump as you flew off the kerb

And now I think about it , most of our wheels wobbled when the bike was upside down and you spun the wheels . I guess all that jumping off kerbs had done what? Messed up the spokes tension ?

[ourclarioncall]

So why would running straight into a kerb or a car be so bad? What happens scientifically speaking ?

We would usually ride towards a kerb then yank up the front wheel to avoid impact . But I do have memories of seeing people run straight into them

[PH]

So why would running straight into a kerb or a car be so bad? What happens scientifically speaking ?

This happens
http://thorncyclesforum.co.uk/index.php?topic=13852.0

With enough force, something is going to give, if you built something that couldn't crumple you wouldn't want to ride it.  the example above is the very comfortable 853 forks, the ST forks would probably have bent a bit less but still been written off, maybe some super stiff MTB forks would have survived, maybe not. Wheel is true but the hub is grinding, tyre was undamaged, frame I'm still using.

In normal use, within the design criteria, it isn't going to be subject to those sorts of forces.  If you found yourself frequently pushing a bike beyond it's intended use, then you've bought the wrong bike.  If you damaged it by occasionally straying outside that design, you'd be incredibly unlucky to do any damage, it does happen, just not very often. 
If you put  "Broken steel bike frame" into google images, exclude the crash damaged and those that have rotted away, there's no many examples left.  Where they have broken it's usually at the high stress points, drop outs and bottom bracket, sometimes you can see they haven't been very well made to start with.

IMO it isn't anything to worry about, the RSF and cyclocross riders have been pushing bikes beyond their intended usage for decades, with very few failures, if I were to worry about such things I'd never get out the door.

 

[martinf]

In about 50 years of regular riding, I have had 5 frame/fork failures on family bikes:

- a very lightweight time-trialling frame that I acquired second-hand about 25-30 years after it had been built. A few years after I bought it the RH rear dropout cracked and came away at the chainstay. I managed to ride the bike home (slowly) after the failure. Conclusion - frame was too lightweight (and being light, probably too old) for loaded commuting.

- forks that broke while riding (nasty), in the early 2000's. This was on a 1960's Moulton, and was due to faulty brazing of the fork crown at manufacture. A known issue that I chose to ignore, assuming that if it was going to break it would have already done so after more than 40 years. So my fault.

- my old twin lateral bike described in another post. Obvious misuse by me of a light construction frame designed for gentle use by a small woman, not for fast commuting by a large man. I noticed the cracks where the twin laterals were brased to the frame before they became a safety issue, they only developed after several thousand kms of me riding the bike.

- a large "mixte" style visitor bike that had been abused by a visitor (bent wheel, slightly twisted forks). I don't know how they did this, but I suspect they ran into something solid. I replaced this by a much sturdier bike (my old mountain bike that had previously been used for fully loaded touring), which should be better able to withstand abuse.

- my wife's first "swan neck" frame, which was donated by a neighbour who no longer rode it. Like my old twin lateral bike, this is also a fragile design of frame designed for gentle use by a small woman. Before I got it from my neighbour it had been abused by her two teenage sons, who broke some of the components. Later on, it was used for a while as a visitor bike, which probably started the cracks on one of the down tubes at the small bridge joining the two down tubes. When I noticed these I scrapped the frame and replaced it (for use by my wife) with a similar but slightly heavier-built frame from another old bike. I got a much sturdier (and heavier) Thorn Step-Through frame for use as a small visitor bike.

All the frames/forks were steel, which generally tends to fail gradually. I avoid using aluminium or carbon fibre frames and forks, preferring steel or titanium (I have titanium forks on my Bromptons).

[John Saxby]

If you found yourself frequently pushing a bike beyond it's intended use, then you've bought the wrong bike.

PH's comment brings to mind some advice I received a long time ago, from a different-but-related-and-relevant discipline:  I bought my first motorcycle as a teenager in the early-mid '60s.  My local Suzuki/Triumph/H-D dealer had been an instructor for dispatch riders in the Canadian army.  His advice to me was: "Ride within your limits and those of your bike.  If you're going beyond the bike's limits, it's time to move up [in capacity."

I've never forgotten his advice, and it's worked well for me.  I rode motorcycles for over half a century in North America and Southern Africa, and only came off once, dodging a kid on his bike on a gravel road in Ontario in the late '60s at a very slow speed, no harm done to anything or anyone.

So far--touch wood, he said, lightly tapping 'is fore'ead--I've never crashed a bicycle, tho' I have managed to tip over a couple of stationery ones.

There are two sets of variables at play in my long-ago advice: one mechanical, the other human. For the former, of course it helps greatly to know the limits of your bike, but it's even better not to find out about those the hard way. That takes us into the human variables. In the latter, the key for me has been anticipating dangerous conditions & circumstances--road/track surfaces; people and animals; other vehicles, esp motorized ones; dangerous weather; and fixed and moving obstacles--and riding accordingly.

[ourclarioncall]

Thanks guys

[ourclarioncall]

Ok il be a bit more specific

What will happen to a unload nomad if I start dropping off if 4 to 6 inch kerbs each day ? I’m 16 stone . With 2.0 tyres

I’m not saying I will ! I’m just saying this is probably the worst abuse(?)  I would like to have the liberty to give it IF I wanted to , without fear of damaging Anything

Ok il ask it this way ….

Can I ride of kerbs multiple times a day on an unloaded nomad or will it damage the bike ? Hope that makes more sense

What will damage first ? The spokes ? The wheel will get out of alignment and start rubbing on the v brake or disc pad when the wheel goes round ?

What if I started loading up the bike with weight and did those carefree kerb drops ? How more more damage could I expect ? And where on the bike would it happen ?

[Danneaux]

I suggest you write Thorn/SJS Cycles and describe your intended use just as you have here so you can check in advance of purchase to see if any resulting damage would be covered by Thorn's warranty. That is really the ultimate focus of your question: Will the bike break and by implication, will the resulting damage be covered or am I responsible for it?

You can download a copy of Thorn's Owner's Manual here: http://www.sjscycles.com/thornpdf/ThornBikeOwnerManual2Web.pdf

...and read the warranty specifics on page 31 which state...

Frame and forks
The frame and forks have a lifetime warranty against defective manufacture and materials (except the Thorn Voyager and ME’N’U2 which carry 5 year warranties).
This warranty applies to complete bike purchases and for the original purchaser only.
This warranty does not cover accident, wear and tear, misuse, abuse or improper maintenance.
After the first year, the outcome of any lifetime warranty claim is at the sole discretion of Thorn Cycles Ltd.

Component parts
Component parts fitted to the frame and forks are warranted against failure or defects for 12
months from the date of delivery.
This warranty does not cover accident wear and tear, misuse, abuse or improper maintenance.

There are several clauses you need to read closely, which I bolded.

I can't speak for Thorn (which is why you should contact them for the Official Word), but I would consider habitually riding off curbs loaded or unloaded multiple times a day to be misuse or abuse and would not expect any resulting damage to be covered as it is unlikely to be within the design parameters for a rigid frame. Thorn might or might not agree but as makers of the bike, they are best positioned to advise whether or not it is designed for such use and if they would warranty damage from same. They can also best advise if the bike would stand up to such use. I would be interested to hear their response.

Most bicycle warranties cover "normal use" for a defined period of time; the term "normal use" is open to interpretation but ultimately is subject to determination by the maker's warranty department or their agent/dealer and evidence of damage will tell them a lot. What is "normal use" to you may not be to them and the end result may be no warranty coverage for a "Just Riding Along" (JRA) claim. The term "JRA Warranty Claim" is well known throughout the industry. Understanding makers will carefully consider each case on its merit, but there are categories and evidence of damage that simply fall outside the definition of "normal use". Rider weight coupled with speed, obstacle height and frequency are all to be considered. On the rare occasions I have needed to ride off a curb with the bike laden or unladen, I always go very slowly and generally place one foot on the ground and use the brakes to ease the transition rather than launching off at speed. I would never even consider riding into and over a curb from the street.

Just out of curiosity, why would you want to drop off curbs so frequently if desired? Unless one is riding on sidewalks, there is usually no need and if you are, then there is the matter of clearing the curb from the street as well. It is better to simply lift or ease the bike off the sidewalk or use a curb cut/ramp so you can ride in the street or bike lane.

Best,

Dan.

[ourclarioncall]

Argh , wrote a post and lost it ☺️

Try again, here’s the short version. I’m a gentle laid back person and rider and gave up flying off kerbs many years ago. So I have no desire or intention to do it with a nomad. But I can see what I said sounded like I wanted to thrash one like a teenager on a BMX 😊

It’s more hypocritical/analytical

Hope that makes more sense

I used the kerb dropping as that would the most common form of knock a bike would take in daily use

I just want to understand how strong bikes are in general and where and how they break down and in specific a thorn nomad which would apply to me if purchased

I’m planning visiting a city in Scotland soon , so I’ve been looking at a map so I know where I am . I also want to know my bearings and have a rough idea of where the boundaries of the city centre are. I have no desire or intention to go near those boundaries , I just want to know where they are in contrast to where I am planning on being .

If I buy a power tool I want to know what it can handle so I don’t damage it. If I don’t know then fear will come in and steal my liberty and enjoyment and will end up using it to a much smaller capacity than it is safely capable of

[Danneaux]

I just want to understand how strong bikes are in general and where and how they break down and in specific a thorn nomad which would apply to me if purchased

This topic from the Forum archives should answer many of your questions about where frames and parts can fail. I compiled it nearly a decade ago and many if not most of the links are still good...
http://thorncyclesforum.co.uk/index.php?topic=3955.0

Thorn (and their designer Andy Blance) have taken great care over the years to address any limitations in their frames for a given intended use. One example is the use of socketed rear dropouts which address a common failure point on other frames (typically just ahead of the dropout on the drive-side chainstay). In the case of the Nomad, there are even additional corner braces in between the chainstays and seatstays just ahead of the dropouts on both sides, in keeping with its intended use as a heavy-duty tourer.

Best,

Dan.

[martinf]

If you want to ride up kerbs it would be best to have the largest diameter, widest and toughest tyres possible.

For a short period in the mid 1980's I had a job driving urban buses, so had to frequently drive over kerbs, mainly to get the bus around badly-parked cars.

One weekend I hired a car to go to a wedding with my wife, and without thinking I drove it (slowly) over a fairly high granite kerb while turning the car around in a cul-de-sac. Doing this destroyed the tyre. Car tyres are generally much tougher than bicycle tyres, but are smaller, narrower and more fragile than those used on a bus.

On one of my regular local trips I have a bridge crossing where I use the pavement (= sidewalk for US) rather than the road, as the road is narrow and separated by high concrete kerbs from the pavement. To get onto the pavement is easy, I use a ramp a few tens of metres from the bridge. At the other end there is a kerb with a drop of about 13 cm, so I stop, put my feet down, roll the front wheel off the kerb, then advance very slowly with my weight off the saddle to drop the rear wheel off as gently as possible.

I don't think I have ever tried to ride a bike up any significantly high kerb, anything over 2-3 cms I look for a ramp or stop and lift the front wheel and roll the rear wheel over with my weight off the bike. I have occasionally ridden off higher kerbs a few times when not paying attention, so far without ill effects.

Potholes are another risk. Where I live, these are very rare on urban roads. If riding on tracks and paths I either avoid deep potholes (and significantly sized sharp rocks) by riding around them, or I stop and push the bike if there isn't enough room. I have been caught out a few times, the only damage sustained on a full-sized bike was when I hit a pothole going down an otherwise very smooth mountain road at about 60 km/h with a full touring load, this dented the rear rim slightly. I am a bit more careful on fast descents nowadays. 


 

[in4]

You’re over thinking, my latent Thorn owner lol. The huge canon of Thorn data and experience is viewable all over the ‘net. Unless you intend to do something highly unusual the evidence base provides copious examples of Thorn bikes’ robustness and suitability for your intended use.

Which model will you chose?

You’re welcome 😀