Bicycle Mechanics - Understanding Bicycle Wear

I am a little confused on the relationship between dollars (quality components) and the wear life thereof. If you spend a whole lot on parts does that mean they will necessarily last longer or just perform better in the meanwhile. I know that the answer depends on what part it its but I am speaking in generalities.

Let's say you have a $350 Trek 4300 and $1800 Trek 850. Both bikes are ridden in 100 % equal conditions. The conditions are all hardpack flat trails and a fair amount of pavement. THese bikes will be trail bikes. THere will be no jumping, ramping or anything rough. Both bikes are ridden by the same rider for 3,000 miles. (remember this is hypothetical) WHat will supposedly last longer? I have listed the specs for the bikes below. I am not comparing these two bikes for the sake of purchase. Again I just want to understand what to expect in terms of reliability from a less expensive versus a more expensive bike given the conditions listed above.

What will wear out first? (hypothetically :p ) I think what I am most interested in is drive train including deraillers. Where should a person put his money to keep on pedaling down the road? I would love to hear any comments from experienced mechanics and/or riders.



TREK 8500
FRAME ZR 9000

SUSPENSION Fox Float RL

WHEELS Bontrager Race Disc, tubeless compatible

DRIVETRAIN:
crankset Bontrager Race 44/32/22
rear derailleur Shimano Deore XT

SIZES 15.5, 17.5, 19.5, 21.5"

COLORS Matte Lava Black/Matte Black

Advertised Retail $1,869.99*

Side by Side
Compare the features of up to three Trek bikes at once.
Trek Technology
ZR 9000 alloy, lighter than titanium, stronger than steel.
The Essentials
The right bike isn't the only thing that makes a great ride. You also need the right accessories.

FULL SPECIFICATIONS

FRAMESET:
FRAME: ZR 9000
Frameset available.
FORK: Fox Float RL

WHEELS:
WHEELS: Bontrager Race Disc, tubeless compatible
TIRES: Bontrager Super X folding, 26x2.1", 49/48

DRIVETRAIN:
SHIFTERS: Shimano Deore XT
FRONT DERAILLEUR: Shimano Deore XT
REAR DERAILLEUR: Shimano Deore XT
CRANKSET: Bontrager Race 44/32/22
CASSETTE: Shimano Deore XT 11-34, 9 speed
PEDALS: Shimano 520, clipless

COMPONENTS:
SADDLE: Bontrager FS 2000
SEATPOST: Bontrager Race
HANDLEBARS: Bontrager Race Lite, 31.8
STEM: Bontrager Race X Lite, 31.8, 7 degree
HEADSET: Alloy Aheadset, semi-cartridge, sealed
BRAKESET: Shimano Deore XT Disc w/Deore XT levers

TREK 4300

FULL SPECIFICATIONS

FRAMESET:
FRAME: Alpha SL aluminum
FORK: InSync 323

WHEELS:
WHEELS: Alloy F, Shimano RM40 R hub; Matrix 750 rims
TIRES: Bontrager Connection Trail, 26x2.0"

DRIVETRAIN:
SHIFTERS: Shimano EF29
FRONT DERAILLEUR: Shimano C050
REAR DERAILLEUR: Shimano Alivio
CRANKSET: SR XCC150 42/34/24
CASSETTE: SRAM 850 11-32, 8 speed
PEDALS: Alloy platform, clipless adaptable

COMPONENTS:
SADDLE: Bontrager Sport
SEATPOST: Bontrager
HANDLEBARS: Bontrager Sport, 25mm rise
STEM: Bontrager, 25 degree
HEADSET: Aheadset, semi-cartridge, sealed
BRAKESET: Alloy linear pull w/alloy levers

DISC OPTION:
BRAKESET: Shimano Alivio mechanical disc w/alloy levers
WHEELS: Shimano Alivio disc hubs; WTB Speed Disc rims

This is why I ride a simple, fixed, one geared bike...

This is why I ride a simple, fixed, one geared bike...

Uhhhhhhhhh. Thanks............................I think? :o

There are so many differences in the components and materials its difficult to say yes or no.

Lets use the frame for instance. Suppose you could measure fatigue. Give each frame a baseline of 100 then measure it at the end of the test. If the alpha SL frame was at a value of 80% of its original stiffness and the ZR9000 frame was at 70% of its original stiffness does that mean the Alpha SL frame lasts longer?? NO. Maybe the ZR9000 frame was stiffer to start out with. Also, ride fell is different between the two. So, even if the Alphs SL fatigues less if may feel like crap (poor feed back). The geomotry of the 4900 may be less 'racey'

Wheels: Less expensive wheels may last longer...sorta. Expensive wheels generaly have lighweight rims and fewer spokes to make them more race oriented. Obviously a heaver rim of the same box construction and more spokes will make a more durable wheel. More expensive wheels will have hubs that last longer. The bearing races are smoother and harder therefore the bearings will spin better and wear less.

Components. As components get more expensive the materials used are generaly better. For instance an upper level crankset will use forged arms and chainrings. Forgings are more dense therefore they can handle larger loads and wear much better. This is a major reason I discourage people from buying anything other than forged chainrings. Those CNC'd rings, unless forged, wear very quickly and the shifting sucks because they flex to much.

In a nutshell, yes, a more expensive bike will last longer. There is a point at which a bike becomes so light it cant withstand the stresses a slightly heavier bike can.

How well do you think a 2000lb pick-up truck will hold up on a construction site. Its made of the same materials as a 4000lb truck.

The Trek 4300 will wear out much quicker.

Now, if you were to compare my Trek 6700 to a Trek 8500 I will tell you that it will last just as long....except for maybe the fork.....The Rockshox on my bike sucks...

Looking at those two bikes first to wear out woudl be the tires :)

Next as far as wheels the 8500 wheels would be a bit ligher and probably have better seals. So that would mean higher maintenance on the Shimano hubs, now if both are maintained properly both should last quite a while.

Now the fork the insync is a extremely low end fork, you are looking at ALOT less travel.. less options.. alot less plush a ride with that one.. and fox would most likely last longer.. has better seals.. better springs.. better parts all together.

Now the 8500 hydraulic while the 4300 has mechanical.. so you will have more power and better modulation with the 8500 lifespan probably roughly the same.

Derailleurs lifespan XT will most likely last a bit longer and will definately shift alot smooother. As for the chain the 8sp chain will probably last longer since it is not as narrow as the 9sp one.. same with the cassette..

Not to mention, the 4300 probably weighs a ton.

Not to mention, the 4300 probably weighs a ton.

Does this matter if you are riding flat, hardpacked trails and pavement? It also does not effect wear life does it?

Again, I am not trying to argue that the 4300 is a "better" bike. Obviously it isn't. I am concerned with mechanics. Besides what has been previously mentioned, what will wear out first? Specifically, what in the drive train will wear out first between the two bikes. I believe that the chain rings may be inferior.

IOW, what would you upgrade to try and just make the 4300 stay on the trail as long as it's challenger? I am not interested in comfort, performance etc. I am just talking about not breaking.

In my personnal experience the wear life of most parts is just not an issue (except maybe chains). One of my bikes is a low-priced mountain bike I bought in 1988. It has many 1000's of miles on it and still works fine. It still has original deraillieurs, seat post, shifters, brakes, etc. It shifts and brakes as well as it every did.

In fact, I'd go out on a limb and say that the more expensive a part is, the more likely it is to be changed out because of obsolescence/fashion instead of wear. I hear plenty of comments about upgrading to the 2004 Dura-Ace groupo, and none of it has to do with wear!

The only reason to go for expensive parts is:

1. Functionality (better shifting, braking)
2. Weight (if you race)
3. New toy appeal
4. Fashion appeal

I believe many people order this list the other way round.

In my personnal experience the wear life of most parts is just not an issue (except maybe chains).
In fact, I'd go out on a limb and say that the more expensive a part is, the more likely it is to be changed out because of obsolescence/fashion instead of wear. I hear plenty of comments about upgrading to the 2004 Dura-Ace groupo, and none of it has to do with wear!

The only reason to go for expensive parts is:

1. Functionality (better shifting, braking)
2. Weight (if you race)
3. New toy appeal
4. Fashion appeal

I believe many people order this list the other way round.

That is very interesting. I almost suspected as much. I am sure there will be many that disagree with you but my life experiences have shown me something similar.

The problem is that when a person goes and researches a topic like the quality of mountain bikes and MTB parts the info that is usually given seems relative to performance, and preferance over functionality. Not everyone can afford a Cadillac.

if you maintain it properly, any bicycle should last you damn well near a lifetime.

These two bikes are very drastically different in the quality of the componentry. The majority of the components will last longer on the 8500 because they are made better and to tighter tolerances to start with. The are also lighter and will perform better, but I can tell you from experience that the parts on the 8500 will have a longer usable life then those on the 4300. Frames will probably both last about the same, forks maybe (though the insych fork is not even close to the same league performance wise as the Fox, they have proven fairly durable for general riding). Other parts such as brakes, saddle, stem, etc. will be about the same. The derailers on the 4300 will wear out faster then on the 8500. They will get sloppy quicker and lead to poorer shifter at a much faster rate then the parts on the 8500. Same with the shifters. You are also much more likely to have some problems with the cranks and bb on the 4300.

Like another poster said, at a certain point you can get parts that will last about as long as the ones on the 8500 for less money, say at the 6700 level or thereabouts. As you get into higher priced bikes you get longer life up to a point, and higher performance/lighter weight all the way up the line.

These of course are my oppinions, but they come from my experience spending years working in bike shops (both of which have been Trek dealers, not that it really matters) and servicing bikes of all quality levels on a regular basis. The people who buy cheap bikes and really put the miles on them wear things out pretty quick. For most people buying cheap bikes it isn't as much of a concern because they don't put in nearly as many miles as most of the people buying the higher end bikes. With those who do however, we deffinetly see a difference in the component life of the low end parts compared to the mid & high end parts.

Funny thing is, my beefiest, most durable and theoretically longest lasting bike is the first to need repair.

Heres why: I built a freeride bike, which is basically meant to huck 8 ft drops to flat pavement, thrash downhill descents, and launch off gap jumps. Even though it has an oversized CroMo gusseted frame, I am sure it will be broken long before my roadie's light aluminum frame. I would never put an XT derailleur on because I will most likely tear it off soon.

My point is that bikes are built to serve certain types of riding, and its the combination of the bike type and riding type that determines lifetime (toss in a bit of luck as well). If you buy a burly downhill rig, and ride it on the road nice and slow, it will probably NEVER need service. Get a road bike and ride it in cyclocross and prepare to spend alot of time in front of a truing stand, and ordering new parts.

So don't worry about lifetime, worry about whether its a bike that fits your intended riding style (and watch out, you might find yourself drifting in style, and coveting other bicycles very soon!)

If all you are concerned about is riding a non-broken bike, the choice seems pretty simple to me. Take good care of each bike, i.e. keeping the drivetrain (I agree would be first to wear out, next to tires) clean etc, and only subject it to riding on hardpack flat trails/ pavement, and the 4300 will provide you many more miles for your dollar.
Components are going to wear out, period. An XT Derailleur MAY last longer than an Alivino, but not as long as the replacements you will can buy with the $1400 you've saved. Like you said, you're not going to get the same quality, performance, etc, but that's not the issue.

I think the main difference will be in how well the components work and not in how long they last. A mercedes is not going to last that much longer than a chevy with the same level of care. The quality diference is notable though.

My conclusion is that spending more on drivetrain components could possibly make a bike go farther but there is no guarantee of that.

Obviously, I own the Trek 4300. I have put around 600 miles on it in a couple months. I am having a blast riding and want to get a better bike eventually. Is there any reason to upgrade a bike of this caliber or should a person just move on when it starts to wear out?

Back to the topic, I have gotten a lot of advice from people suggesting buying a used better quality bike. They suggest that would be better than buying a Recreational MTB. I don't think I subscribe to that theory. I watch some pretty worn out looking bikes go for unbelievable $ amounts on Ebay. People aren't all stupid so there must be some validity to it.

I just personally would rather spend $600 on a new bike than $600 on a used bike that is supposed to be a better performer. I guess that is just me.

Here is a quick answer. Generally the more expensive components work better, are lighter, and wear better. UNTIL you get into the realm of race components (XTR and such). They generally are SO light and performance oriented they wear out faster.

Here is my real life experience, FWIW. I do lots of hill climbing and I am a fairly large rider (6'1" 200lbs).

I started out with a combination of LX and XT. As things have worn out or broken I replaced them with XT or something I deem to be better.

You will wear (stretch) the chain. You will also wear the cassette and chainrings. The jockey wheels also wear out on the derailer. However, if you are a casual rider, you may not even notice until the shifting gets really bad.

When I lived in New Zealand (very wet). I could burn up a set of Shimano brake pads in 2 - 3 rides. ($20.00 a set down there)

If you have not ridden a bike with nicer components you won't know the difference. Once you do though, you won't go back. I personally wouldn't go below LX as long as I could afford it.

When I started mountain biking I had STX deraileurs which lasted longer than any XT or XTR stuff I've had since. I look at it sort of like a Jaguar... It is so finely tuned that it is always needing adjustment. Now that I've got the bike and parts I've always wanted, I'm always having to adjust and/or replace parts because they are so finely tuned. Mostly when you get into quality, you are dealing with very light parts that are more for performance than durability. The exception is with extreme downhill or freeriding equipment like the Saint line which is made especially for durability.

The flip side to that is with your hypothetical situation, an XTR probably would last longer than a Deore or LX if it is not getting abused and just riding on flat land. They are made with better quality, and should shift perfectly for a very long time. Also, when you get into higher end materials the wear time will be much longer.

I just think if you aren't into intense riding or racing, a steel frame with LX should last pretty much forever.

As many have said, if you take care of your rig it will last you a long time (dh and fr rigs excluded).

MY personal expieriance, my higher end race components have out lasted any of the lower end components. My more expensive wheels have lasted longer, derailers have lasted longer, ect., etc., etc.

Being able to do the general maintenence your self and knowing how to adjust things properly will help you get the most out of your rig. You will also be able to distinguish between "worn out" and "just needs adjusting".

If you are the type of rider that will ride more aggressively as your expieriance grows then you should get a rig that will be able to handle the harder riding. If you believe that you will never do more then just ride flat fireroads and/or pavment than most any rig will last.

:beer:

On the subject of used bikes, they can be great deals or big mistakes, buying off the net is a gamble. If you can find a used bike locally that you can inspect, then you may be better off. We have people bring in used bikes they are thinking about buying to our shop fairly often, we'll always give them a good checkover and give the person our oppinion of wether the deal is fair or not. I've seen some people get great deals that way and they got tons more bike for the money. I've also saved a good number of people from making big mistakes buying bikes with old, worn out parts and other problems.

One tip for used bike buyers, if your looking for high end stuff locally, it's a good idea to ask around the local shop. Employees get great deals on bikes and parts and becuase of that will often switch bike once a year or so. Employee bikes are almost always very well maintained and not very old

Thirty years ago, Campag. bearings, cones, and races were harder and machined to closer tolerances than those of most competitors, and the stuff did last a long time. I think the difference is much smaller today, although higher-end Shimano parts may be more durable than lower-end parts.

I have worn out (definition: 1/2 percent elongation) many chains, several cogs, a few chainrings, and countless tyres and brake pads. I have also broken three steel frames, two rear axles, two left cranks, a front hub flange, and a pedal cage. I have also worn out several rear derailleur pulleys, but the only truly worn-out derailleurs I have ever owned were a 1959 Campag. Gran Sport push-rod front and a bargain-basement Shimano MTB front.

I think the main difference will be in how well the components work and not in how long they last.

That statement contradicts itself.

Both bikes may last forever. The Trek 8XXX will perform closer to the way it did when it was new. In other words the percent drop off in performance is less.

Something to consider also is the frame. The 4300 is 'sport' geometry, the 8700 is 'race' geometry.
John, the same still holds true with the high end Campy/Shimano components.