quote:
Mountain Biking is a vague term these days
quote:Strength may be an issue but geometry is the primary answer. The Catalyst uses a short chainstay (408mm). This has two effects
what it is about the Catalyst frame that means it can't handle more than 20kg luggage
quote:
don't get it into your head that the Catalyst's fragile!
quote:
Originally posted by stuthoquote:
don't get it into your head that the Catalyst's fragile!
Well said Jawj, however I would be more concerned with the geometry than the tubes if you are thinking of exceeding the 20kg limit
Have a look at this thread (http://"http://www.sjscycles.com/forum/topic.asp?TOPIC_ID=1190") it is here that I have got the 20Kg (on road) limit (from Andy Blance)
quote:
Originally posted by bike_the_planet
But for what weight of rider?
I do think that there is some exaggeration made with talk of luggage weights when rider weight is not included in the equation!
Cheers,
quote:
Originally posted by ians
this is a good point and something I've often wondered.
Perhaps it's something to do with where the luggage (weight) is concentrated. The rider's weight is distributed more or less over the whole bike - heavy panniers can hang on a flimsy rack in one particular place on the bike. Maybe that causes additional stresses.
Just a thought.
ian
quote:
Originally posted by stutho
Just to muddy the water a bit more...
The weight of the rider is NOT equivalent to the weight in your pannier. Why not? Three reasons:
As you are riding over a bump your arms and especially your legs act like a shock absorber. This substantially reduces the impact load on the bike, as well as you!
Centre of gravity, as others have mentioned. This is especially important under heavy front braking. Far greater forces can be generated in the headset and the front forks. Normally a bike will endo under heavy front braking however it takes far more force for this to happen when the weight is so far back (and low down).
The finally issue with pannier weight is the attachment points. Under static conditions the weight is carried by the dropouts a very strong location, however under rapid deceleration (say by hitting a big bump) a large force is transmitted from the panniers into the seat stays, mid tube - this is NOT a strong location.
I agree that some allowance should be made for rider weight. This is mentioned in the OP. Unfortunately it is not an easy calculation to make. I would also claim that road conditions are more important than the weight carried.
Final point (honest!) Andy Blance has designed some of the finest touring bikes in the world. He also does some serious touring himself He knows his stuff and his advice can be trusted.
quote:
I have restricted the table to Ravens only.
quote:You hit the nail right on the head!
I'm guessing that Stutho's fine table is intended to be useful for the majority of people i.e. those who won't be buying a custom or tandem bike. (I'm sure the people going custom or doubling-up will be having VERY extensive conversations with SJSC about their requirements)
quote:Don't forget that the table is designed to differentiate between the Ravens. I believe that the RT will be better than the RST on unsealed roads (especially loaded) as it has a longer wheel base and therefor greater stability.
...RST was only rated a 3 for dirt roads
quote:I agree it looks like an inconsistency in the table. When I was ranking the City Slicker I was thing more in terms of stop start city traffic, which both the RCS and the Enduro will be Excel with. With all the other bikes (including the Enduro) I rated them more in terms of road touring (i.e. open roads with load) I will edit the OP to reflect your comments. (I should also mention that I have very little knowledge of the City Slicker if any owners want to fill in my blanks please respond.
I've found that the City Slicker, with a 5 road score in your table
I am thinking of an overhaul to the table -
All comments gratefully received
By nature cyclists are always obsessed with bike weight - ( I deliberately don't weigh mine anymore!) - The low gears on the Rohloff will get me up any hill relatively easily & the Thorns geometry & comfort via the 26" wheels provide a great ride/ handling - the weight is not really an issue.
Stutho, have you posted any pictures of your 12.7Kg RST, or have i have not noticed them before?
I for one would like to see it, if its not being too cheeky!!
I had access to a digital balance recently and weighed my raven tour at 15.8kg. That's with schmidt dynamo hub and lights, additional battery light, rohloff of course, brooks saddle, tubus rack, carbide rims, schwalbe marathon tyres, single sided SPD pedals. All chosen to be robust and bombproof for my kind of touring and commuting.
Which Nomad to get?
A STD Nomad MK2 or a Nomad MK2 X?
Nomad X + trailer?
What size? With the introduction of the X series Thorn started adjusting the load carrying capacities depending on the frame/rider size, and this makes a lot of sense. In my experience, the frame strength varies hugely depending on these few extra cm/mm of tube length...
I used to ride the xTc. A fantastic bike but, being XL size, it shook like a jelly with 15kg plus, even on smooth tarmac. Had to replace it with the Raven for a Himalaya trip, which was a good choice (for Himalaya that is, otherwise I really miss my xTc's nippiness). But my partner, who is much smaller and rides M size frame kept the xTc, and just took mudguards off and put 2.0 XRs on. We rode some seriously rough roads in Ladakh, up and down hill, and she had no complaints whatsoever, and the bike handled the load no problem. I carried most of the kit/food/water, but she still probably had around 15 kg on hers, which I guess would be near the xTc limit for smooth surfaces.
So, if you are looking at going lightweight and only carrying 30 kg very occasionally, and if you are looking at smaller/medium frames, I guess you could be fine on the X. If you are a big guy though, this is unlikely to work.
Trailer is a good idea, and frame bags can improve the bike's handling when it would be otherwise overloaded.
Some people will say that you should future-proof your bike and go for the strongest possible frame. Well, I beg to differ - don't get a frame any stronger than you need. Lightweight frames are more fun ;)
It make's a diff about which size bike?
Congratulations! I really hoped though to finally read a review of the X series. :-\
Congratulations! I really hoped though to finally read a review of the X series. :-\
I think the problem in specifying the max weight is what Kind of surface are we talking about. I have used my RST with far more than the Max specified by thorn. (It did make the handling lively but didn't damage the bike) It would be great if Thorn would publish a list of max weights - split into 3 columns - Comfortable Load, Max load, Off Road Load
Stutho
Dan is probably the best to give advice on running max weights off road. I rarely ride off road but am much more careful to avoid bad potholes with the bike heavily loaded than not.
I know the answer is a bit fuzzy wooly but life is just sometimes like that.
Steel doesn't fatigue, right?Well, yes, it can given the right circumstances -- for an example, try bending a paper clip too many times. A friend owned a used-bike shop for 25 years, and instead of sending all his damaged frames (mostly buckled top and downtubes and forks all damaged by curb-strikes) to the metal-recyclers, he gave the nice ones to me with the proviso that I never sell or ride them. Agreed. I cut up any number of them, and used many to learn and hone my lugged- an fillet-brazing skills. When I was a regular member of a particular listserv, members would occasionally send me their out-of-warranty failed frames for analysis or possible repair (tube replacement). There was one prominent brand of some repute that had a problem with the lower end of the seat tube cracking clear through above the bottom bracket. There was a direct correlation between the tubing gauge used (too light) and rider weight/style (big guys who were mashers in their pedaling styles). There were a lot of cracks in the seatstays just ahead of the right-rear dropout and sometimes in the dropout itself as well. Seatstay and dropout replacements are relatively easy on brazed frames. Seat tubes...not so much. I wrote those off, but the rest of the frame tubing found its way into my various projects over the years, where it happily does just fine. I have a 1972 Windsor Professional (a Colnago copy made in Mexico of Columbus tubing) I bought used that has had its head tube professionally replaced at some time in the past -- as did most Windsors of that model and era. The problem? The head lugs were overheated during brazing, leading to early failure.
Not that I want to disagree with Dan but bending of a paper clip is taking the steel beyond its limit of flex and will therefore damage it. The beauty of steel is that if you keep it within its limit it does not fatigue.
No disagreement from me, Andy; and you're right about steel not fatiguing within its limit! <nods> The key is "within its limit".
...I would expect the weak spot to be at the welds.<nods> Yes, Frank, I am largely agreed; the most likely place for a fracture or crack propagation to occur would be at the welds.
<nods>
Frank...I'd like to offer a suggestion for you to ponder (you'll know best if it might prove suitable for your use): Have you considered a trailer to ease the load on a lighter bike? While the overall weight might be the same or more than you presently have, the stress/load carried on the bike would be less, since it is shared by the trailer. The result might keep you well within the Nomad X's weight limits. I have been testing the Extrawheel trailer and am impressed by how it allows a lighter bike to carry heavier loads than it could manage otherwise. Perhaps something like that (with large wheel) would allow you to carry your present or occasionally heavier loads on a lighter, more lively Nomad X without incurring wobble or the possibility of frame failure that could occur by putting the weight on the bike alone. Much to my surprise, I have found the trailer to be almost unnoticeable in much of my on- and off-road testing so far.