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Don't buy plastic cranks
#1
I replaced the chain ring on my bike recently. The new one I bought had AVANTI written on the cranks in large letters. I expected, with a name like Avanti, it would be good quality. It had steel internals, and plastic on the outside of the cranks.

When I went to accelerate quickly, the crank broke. It turns out the steel in the middle is very thin, thin enough for the crank to break when accelerating quickly.

I believe these things are designed to break easily, so they sell more products. I believe it is disgusting what companies manufacturing bicycle parts are doing.

If you are a person who really puts power to the pedals, I recommend don't buy cranks coated with plastic.
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#2
how about some pictures of what you have
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
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#3
(12-04-2022, 05:36 AM)ichitan Wrote:  I replaced the chain ring on my bike recently. The new one I bought had AVANTI written on the cranks in large letters. I expected, with a name like Avanti, it would be good quality. It had steel internals, and plastic on the outside of the cranks.

When I went to accelerate quickly, the crank broke. It turns out the steel in the middle is very thin, thin enough for the crank to break when accelerating quickly.

I believe these things are designed to break easily, so they sell more products. I believe it is disgusting what companies manufacturing bicycle parts are doing.

If you are a person who really puts power to the pedals, I recommend don't buy cranks coated with plastic.

Plastic pedals and cranks are meant to be replaced. I know a handful of friends who rock plastic cranks and they always end up replacing them with some metal cranks.
Manufacturers usually put them there because it makes the bike cheaper and people who are looking to spend little can buy some good quality frames or shocks at the cost of this. I am guessing they also gave you plastic pedals.
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#4
(12-04-2022, 09:31 AM)Talha Wrote:  Plastic pedals and cranks are meant to be replaced. I know a handful of friends who rock plastic cranks and they always end up replacing them with some metal cranks.
Manufacturers usually put them there because it makes the bike cheaper and people who are looking to spend little can buy some good quality frames or shocks at the cost of this. I am guessing they also gave you plastic pedals.

I replaced my chain ring because it had the top off 3 teeth. When I bought the new one, I thought with a name like Avanti, it must be good quality. It is clear now, it was designed to break. Even if someone applied less power to the pedals than I do, it would flex a little, and break from fatigue after some time.

I do have a problem with bending and breaking pedals. The pedal axles are getting thinner. I am on the third set of pedals in 6 months. With the first set the axle bent. With the second set the axle broke.

The pedals I am using now, I picked up used. They are plastic, but made some years ago. The axles are stronger in these older plastic pedals, than in many new pedals. No doubt, at some time in the future, the bearings may fail, or I may smash one against a rock, or something. Bike parts don't last forever.

A local bike shop has some nice looking aluminum pedals, but they are thinner than old style pedals. I suspect the axles must be thinner, and would bend or break. Has anyone had any experience with these modern thin aluminum pedals.

While people making bike parts make more money by making parts that break, it can be difficult for cyclists. Sometimes parts break when you are a long way from home. Sometimes you have to walk a long way. Sometimes after dark. When the pedal broke, I finished up with a scratch on the inside of my leg from the sharp end of the broken shaft.

Smart cyclists learn which parts are likely to break, and which parts are likely to last. Companies making parts which break will eventually get a bad reputation, which will be bad for their business.
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#5
you must just be buying low grade pedals. They do make make decent quality "resin" pedals. However on should never really skimp when it comes to pedals, they can make or break the way the bicycles feels while riding. your use of terms make things a tad confusing because the do not make plastic cranks, they do make stamped steel chainrings rivited together that have a plastic disk to make them look nicer and some to act as a guard. steel rings do not typically break off teeth. They may have different size teeth used as shift points that may appear to look bad to a non mechanic unfamiliar to parts design. Part of the reason I ask for clear photos of all that you have. I have never heard of Avanti bicycle parts myself.
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
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#6
(12-04-2022, 03:36 PM)Painkiller Wrote:  you must just be buying low grade pedals. They do make make decent quality "resin" pedals. However on should never really skimp when it comes to pedals, they can make or break the way the bicycles feels while riding.

With some people, when something breaks on their bike, they order the ideal parts online, and wait 2 months to get it. I like to fix my bike as quickly as possible, so I can ride it again. So I look for what I can buy here and now. If all I can find is plastic pedals, that is what I buy. I mentioned above that there are some nice aluminum pedals in a shop, but they are very thin, which suggests the axle is thin, and maybe not very strong. Maybe the axle is made of harder steel, and the pedals will last a long time. Plastic pedals are a lot cheaper, so I tried them first.

I do some riding on rough tracks. There have been times when pedals have hit rocks. If a cheap pedal gets smashed on a rock, it is not expensive to replace.

I am getting fitter, and riding longer distances. So bike parts are wearing out quicker.

I am larger than many cyclists. Some of the parts I have broken, would not break with a smaller rider.

I am also going through a learning curve. A few years ago, bike parts did not break like they do now. I am learning what parts are tough, and what parts break quickly. Certain things I wont buy again.

(12-04-2022, 03:36 PM)Painkiller Wrote:  your use of terms make things a tad confusing because the do not make plastic cranks, they do make stamped steel chainrings rivited together that have a plastic disk to make them look nicer and some to act as a guard. steel rings do not typically break off teeth. They may have different size teeth used as shift points that may appear to look bad to a non mechanic unfamiliar to parts design.

My old chain ring did have teeth broken off or worn off.

They do make plastic cranks. Maybe you would call it resin or something else. They have a thin piece of steel up the middle. Very thin. The steel in the middle acts in tension, and the plastic acts in compression.

(12-04-2022, 03:36 PM)Painkiller Wrote:  Part of the reason I ask for clear photos of all that you have. I have never heard of Avanti bicycle parts myself.

I have had poor quality parts with Shimano written clearly on them, and now this with Avanti written clearly on it. I can't say for sure these are not fake parts, and have just written the Shimano or Avanti name on them. There are definitely some fake parts being made and sold.

I have not taken photos yet, and I am not sure it is important. It would show how thin the steel is in the middle of the plastic crank, which would shock a lot of people. If people just don't buy plastic cranks, problem solved.
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#7
The pictures would help me learn something evidently, now I would like to see and know what brand of bike we are talking about here also. Here is a tip for learning curve. especially when starting with low end parts. If the bike is a fit and not a dept store bike always repair with better quality parts if equal too is not good enough in the first place. Sounds like your riding style is more advanced than your components, three sets of cheap pedals is not better than one set of high quality pedals period. I would like to see the model of crank you purchased, maybe a link to it or something, would also like to know your spindle length on the bike. It may not be a match for your new crankset. Did you buy the bike new? what brand is the bike?
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
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#8
(12-04-2022, 08:02 PM)Painkiller Wrote:  The pictures would help me learn something evidently, now I would like to see and know what brand of bike we are talking about here also. Here is a tip for learning curve. especially when starting with low end parts. If the bike is a fit and not a dept store bike always repair with better quality parts if equal too is not good enough in the first place. Sounds like your riding style is more advanced than your components, three sets of cheap pedals is not better than one set of high quality pedals period. I would like to see the model of crank you purchased, maybe a link to it or something, would also like to know your spindle length on the bike. It may not be a match for your new crankset. Did you buy the bike new? what brand is the bike?

What is wrong with you. Can't you just accept that it is good advice to warn others not to buy plastic cranks, and leave it at that.

Notice this response:

(12-04-2022, 09:31 AM)Talha Wrote:  Plastic pedals and cranks are meant to be replaced. I know a handful of friends who rock plastic cranks and they always end up replacing them with some metal cranks.
Manufacturers usually put them there because it makes the bike cheaper and people who are looking to spend little can buy some good quality frames or shocks at the cost of this.

This person has seen others experience a similar thing.
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#9
Thank you for asking what is wrong with me, that is very kind. I am ok, just a little head cold is all. I have no idea how you knew I was under the weather as they say. But then again I have come to realize that your level of intelligence is quite different than mine being a pro member and all. I just wanted to know more about your experience and I do better with visual cues sometimes. Look forward to the pictures I asked for. If you need money to post them let me know that too, as I understand about everything has intrinsic value in todays world. I just want to be sure that I do not ever repeat the stupid things that you have done and I am willing to learn from others mistakes and that knowledge I never want to "just let it go". Your writing seemed a bit vague but I would also be willing to recommend you for a Pulitzer Prize at least for your efforts on this post.
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
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#10
(12-05-2022, 03:27 AM)ichitan Wrote:  What is wrong with you. Can't you just accept that it is good advice to warn others not to buy plastic cranks, and leave it at that.

There is nothing wrong with him, the problem is with you.

Yes, a photo of the problem component would have been very helpful -- both to identify the specific components you were talking about and to better understand the problem (if there is one).

If you had already discarded the broken parts and don't have a photo, that would be perfectly understandable, but your angry outburst is neither understandable nor acceptable.
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