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7

If it were a steel frame and fork there would be no question -- steel lasts nearly forever, even when moderately rusty, and can take all sorts of abuse. Aluminum is a bit less robust, but if it only has "a few thousand" miles on it (and not 30,000) and has not been abused (or hit by a car) then it should be good. The problem with aluminum is that it can ...


7

That is purely marketing. It's a common ploy with components, but I've never seen it on an entire frame until now. Aluminum and carbon can be used in conjunction effectively, but not in this case. The carbon wrap on that bike is basically veneer. While Schwinn was once upon a time a well respected brand, they suffered a major fall from grace after going ...


7

This is actually a matter of the force multiplication that each chainring provides, and the size/mass of each chainring. Force difference Let's propose, only for a moment that you had a chainring as big that the radius of it is almost the same as the crank length. If the rider stood to pedal while using that chainring (and using simple platform pedals). ...


6

I ride aluminum frames almost exclusively and have had no problem with them. The welds are what tend to break first on most bike you hear these horror stories about, but this can happen with any sort of weld (though some forms of welding are more effective than others), so if a bike seems to be too good of a deal to have an aluminum frame, make sure to ...


5

Good question! There are a couple important reasons for the differing materials: Wear: Steel lasts longer than aluminum, plain and simple. So why not use steel on all the rings? The larger rings have ramps on the sides that facilitate shifting and cannot be flipped as the ring wears. The granny ring can, therefore it can last a lot longer. Flexion/Bending: ...


5

Do you know the history of the bicycle (crashed, etc)? While bicycle geometry\components\preferences have changed over the last 12 years, the life span of well cared for aluminum frame and carbon fork are much longer. Clean the frame and fork and give it a thorough examination. Look for: Major dents in the frame that may compromise the integrity (minor ...


5

How much unusual stress are you talking about? The weight of the bike all on one leg of the fork? Or the weight of a really large person leaning back against the fork? If it's just the weight of the bike leaning "wrong" on the fork, I wouldn't worry about it. That fork leg is built to handle a lot more stress than that in normal riding. If it's worrying ...


5

For the carbon fiber to be of any use structurally, it has have multiple layers. If it says it is wrapped around the aluminum, my bet it is for show only so it gives the appearance of being an expensive frame when it is clearly not. There is no way that a composite of the two will be very light without being very weak if it were compared to a full Carbon ...


5

You'll definitely need to remove all components. For threaded bits you have two choices - leave junk bolts in there that will get powdercoated over and then carefully remove them (leaving a bit of an edge around the bolt hole) or let them get masked but almost certainly somewhat powdercoated into and use a tap and die set to chase them before reassembly. ...


5

I am posting this as an answer but it is more of a long comment. The information I have is from the place I trust to do carbon repairs. According to Hot Tubes aluminum and the carbon resin react. The aluminum must be sealed to get a good bond. The materials are not your hardware grade epoxy. If we were talking about a fishing rod or something that would not ...


4

Yep, "raw" aluminum develops a layer of corrosion fairly rapidly. Thankfully, unlike with iron/steel, the corrosion is "tight" and eventually develops to a thickness where additional corrosion is prevented (in normal circumstances). The corrosion can be prevented by either coating the aluminum with a lacquer-like coating or "anodizing" it. Anodizing is a ...


4

Never use a hammer. In order to check the inside of the frame, visual inspection most times FAIL, because the problem is caused by tiny bumps or misalignments that are not easily seen with naked eye and even felt with fingertips. I would recommend that you take another seatpost (an old one you can take/borrow on a local bike shop) and try to insert more ...


4

2 things: While many older forks used replaceable steerer tubes, the steerer tube is still specifically shaped for that fork. Tubing will not do it. You need an oem replacement steerer tube. Nobody makes forks like that anymore, hence the lack of google results. Also, that steerer tube in the photo looks to be steel, and should not be replaced with ...


4

To identify a frame firstly see if a magnet sticks, if it does it's steel, if not it's carbon, aluminium alloy or titanium alloy. If not steel look down the seat tube if it's metallic inside it could be aliminium or titanium if black and plastic looking, carbon. Tap the frame with a screw driver, aluminium and titanium will have a definite metallic 'tink' ...


3

Mainly, due to "lever arm" issues, far more force is applied to the teeth of the smallest ring, and they need to be the strongest. This is exacerbated by the fact that the force is spread over fewer teeth. For #2 I'd list weight -- with the small ring using aluminum would save very little weight.


3

I can't see your specific rims from here, but plenty of bikes back in the 70s and 80s had rims that width capable of handling 90-110 PSI. And I definitely wouldn't run a 1-1/8" tire at 65 PSI. I'd imagine that the rims, if designed for tires that narrow, should be able to handle 80 PSI or so.


3

I know in BMX, aluminium frames are too soft. I had a frame and it was designed for racing but I used it for dirt. Did not take too long for the headset (was not setup loose) to ovalise due to it being not hard enough. I did bodge this with shimmys from coke cans for awhile. It's also not a wise idea to put pegs on an aluminium frame as it leads to ...


3

Steel has been the standard for cheap bikes for a very long time. Weight is a prime factor, as noted above. In addition, steel rusts.... If you go to someplace where lots of bikes are parked outside for any length of time, like the university where I work, you can pick out the cheap bikes instantly by the nasty rust that starts forming with great speed. ...


3

Really deep dents or cracks are a cause for concern, but not little dimples and such. Also, the "work hardening" of aluminum is considerably less than industry types would make out....I've worked on numbers of aluminum frames that are at least 20 years old with no sign whatever of any structural problems. Kind of depends what you're doing. The average ...


3

Aluminium frames do not corrode, no need to worry. My 2006 mountain bike frame has lots of scratches and defects, but it is still stiff enough. Aluminium frames have shorter life expetency than steel frames had, because aluminium has a tendency to tire, but it can be used without worries for 10 years. If you are really worried, put a sticker over it :)


2

Steel makes for a heavier rim; the modern-box section design works well for taking advantage of aluminum's lower density. Furthermore, since steel will rust, the rims are typically chrome-plated. The chrome plating makes rim brakes almost useless in the wet, which is exacerbated by the poor pads used on most of the classic bikes that shipped with steel ...


2

sillyyak is right. The weight of wheels makes a big difference. I notice a huge difference in stopping in the rain on aluminum vs steel. On bike forums ( http://www.bikeforums.net/archive/index.php/t-449632.html ) everyone says aluminum is superior for weight and in the rain and so does this girl: ...


2

I ride a 1999 Specialized Allez Pro with an M4 aluminum frame. It's a great frame - light and extremely stiff. Apparently it's had some problems with cracks around the dropouts, but I've had zero problems with mine. I weigh 160 lbs FWIW. You can see others' opinions on this bike over at roadbikereview: ...


2

It would in theory combine some of the characteristics of both, while permitting a cheaper bike than straight carbon. The aluminum could be thinner, providing only modest strength but serving as a mandrel to support the carbon, and the carbon would produce a stiffer bike than straight aluminum. Or it could just be hype. Or the "carbon wrap" could be used ...


2

Everything must be removed from the frame. Powdercoaters will do the sandblast/strip for you generally. Alu must be chemical dipped. Good powdercoaters will put plastic/rubber plugs in the screw holes so that they remain clean. It's always good practice to chase the threads when you get it back from the powdercoater.


2

I have taken a bike to a powdercoater before. Many of them actually do motorcycle frames regularly so they're very good with prepping the surfaces and screw holes and dealing with complex shapes. The hardest thing for me was the fork race-- I had to have it removed by a bikeshop. Some people have success with a DIY approach, but it is safer to do it with ...


2

The problem I had was getting the ammonia to the corrosion. I hung the bike upside down by both tires so the seat post was vertical. You can either remove the bottom bracket or as I did the bottle cage screw and fill the seat post with straight ammonia. If possible plug the hole so the ammonia doesn't evaporate. I let it hang for 2 days. I then laid the bike ...


2

I have an identical problem, having been rinding the bike without seat clamp for more than two years now. I suppose you have already read something about it, if not I recommend Sheldon Brown on the subject. But I must warn you that the ammonia theory didn't work for me, and I tried ammonia on some aluminum sample parts without any visible effect (corrosion, ...


2

The Mosso web site doesn't give a full description. Looking at the photo it appears to be a carbon fork with an aluminum steerer tube. This is not an unusual combination. Many road bikes are offered with this setup. I can't say anything about the quality for the price perspective. I did recently purchase a factory Specialized fork that had a carbon fork and ...


2

If they are the same make, model, and year frame and the proper sized seatpost will not insert into the frame more than 1-1/4" then something is wrong.This one's hard to diagnose over the internet so I suggest you head down to a reputable bike shop and let them have a look at the frame before something gets mucked up irreparably.



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