beginner that can't tell freewheel or freehub difference
The middle sprocket is busted on my $150 walmart bike. I want to fix it just so I can give it to my wife to ride to the park. Meanwhile, I'm upgrading to the GT karakoram 2.0... unless one of you experts tells me that I can get a better quality bike for the same price ($800). I'm looking for something pretty basic in hardtail, no luxuries or conveniences.... just longlasting reliability and quality. Something that overtime I can upgrade and eventually turn into something that is as good as if I had just originally spent $2000. Any suggestions?
Anyway, back to the original question about the broken sprocket/cog (whatever you want to call it).
I have read about the difference between freewheels and freehubs, and I understand the differences perfectly fine. However, the manual to this bike (generic online manual) says that this bike has a freewheel, but based on what I know about them, I think it is actually a freehub. Please tell me what you think it is.......
So my middle rear sprocket is completely detached from the middle piece (hub/freewheel, whatever it is, that's what I'm writing this thread to find out). This so called "middle piece" is a stout metal cylidrical shape about 2 inches long and about 2 inches in diameter. It has metal raises/ridges around the entire thing. The non-broken cogs/sprockets fit into these ridges and that keeps them in place. For whatever reason, the broken one will not seem to lock into the ridges. Based on that description, doesn't it sure sound like a freehub more than a freewheel? To me it seems like the cogs would never break loose like that on a freewheel(since they are suppsedly permanently attacked to the ratcheting mechanism). And if they did somehow magically break free on a freewheel, they wouldn't be grooved (and meant to connect into other grooves) like mine seems to be right? I really think it is a freehub. The manual is claiming it's a freewheel, but I think that's just because schwin makes generic manuals for all of their bikes that are sold in big departments stores. I know one guy already told me that it can be incredibly difficult to tell the difference. In fact, he said that he was surpised once to find out that he actually had a freewheel and not a freehub on a bike he had had for years. He always assumed he had a freehub. He couldn't tell until he actually took it apart.
Based on my description of the broken sprocket and the grooves on the middle piece......what do you guys think?
Last edited by package81; 04-28-2011 at 03:13 PM.
Your Walmart bike has a freewheel. The Karakoram has a freehub.
Here are the differences.
With a freewheel, the ratcheting mechanism (the part that allows you to pedal the cranks backwards) is part of the gear cluster and threads onto the hub.
With a freehub, the ratcheting mechanism is part of the wheel hub itself. And a splined set of gears slide onto the freehub and uses an external lock ring to retain the gear cluster (cassette) onto the hub.
Here is a picture. I do suggest you bookmark the following site.
I just built (or tried to build) two GT Karakoram 1.0 today both had some annoying issues that are gonna cost my shop money to fix. I was pissed and GT is gonna get a call tomorrow. But I also put together a 3.0 and that went fine aside form the fork being a piece of junk.
But anyways, it should be noted that some freewheels are assembled in a way that if taken apart may resemble a freehub. I would assume they do this so they can just make one standard inner workings and slap on whatever cogs need be. I would guess you have a freewheel, as I have seen them fail like that, and don't think I have ever seen a department store bike with a freehub.
Now that's helpful info from "big papa nuts". Thank you. So do you think that I will be able to put a quality freewheel on my walmart bike? Or do you think that because it is a department store bike that it won't be compatible with a quality freewheel?.... or for any other freewheel that didn't come with the bike for that matter? Maybe its such a POS that once the freewheel breaks, you are screwed.
You will likely spend up to 50% of the original price of that bike trying to fix it.
Buy a full spare from craigslist or simply spend the 96+tax on a new one for her.
Isn't this basically what a freehub is? In that the cogs are seperate from the ratcheting machanism? I guess technically that does not make e it a freehub.....I guess its maybe some cheap way of making it look like it is a free hub?
But anyways, it should be noted that some freewheels are assembled in a way that if taken apart may resemble a freehub. I would assume they do this so they can just make one standard inner workings and slap on whatever cogs nee
So I just noticed something interesting about whatever the hell is on my bike. The piece that I thought was a freehub (the stout cylindrical metal piece coming of the hub) is actually not the same diameter throughout its entire length. It changes diameter about halfway through the lenth. The end closest to the wheel is much fatter in diameter than the other end. The fat end has the largest 3 cogs and the small end has the 2 smallest cogs. This difference in diameter appears to be the real reason that the center cog won't lock into the groooves. It has slipped off the fatter portion of the so called "freehub" and is now on the small part. The cog obviously doesn't fit on the small end since it is sized to fit on the fat end. What a POS!!!! Starting to seem like I should maybe take ratmonkeys advice and leave this bike alone. With all these mystery parts that it seems to be made of, its hard to believe that its going to be compatible with real quality parts. I might just leave it be. I just thought it might be good for me to tinker with it so I can get some practice for my next bike. But it sounds like tinkering with this "bike" might do more harm to my bike knowledge than good. Notice how I put "bike" in quotes?
Big papa, Got any recommendations on a better 29er hardtail based on my description of what I'm looking for(see my first post above). I had a salesman tell me that GT was the best for hardtails. Especially for frame stength. He said it had to do with the way the triangle shape is welded in the back. The rear "fork" comes up and through the "seat bar" and attaches to the top bar. I have to admit that that shape does seem a lot stronger. Got any opinions on that?
So whatever pissed you off...does that same annoying thing exist on the 2.0 model? And if so, does it affect me as the buyer/user. Because the 2.0 is actually what I'm looking at getting.
I just built (or tried to build) two GT Karakoram 1.0 today both had some annoying issues that cost my shop money to fix. I was pissed and GT is gonna get a call tomorrow.
I was told that the fork on the 2.0 was a huge step up from the fork on the 3.0. Is that true? Hopefully you will not think the fork on the 2.0 is junk. If you say it is then I will not get it.
. But I also put together a 3.0 and that went fine aside form the fork being a piece of junk.
Last edited by package81; 04-28-2011 at 11:48 PM.
It is actually quite simple to tell the difference between a freewheel and a cassette if you know what to look for.
In the below images the one on the right is a cassette for a freehub, the one on the left is a freewheel. The arrow on the first image is pointing to the lock ring that attaches the cassette to the hub. The arrow on the right is also a lock ring however, it holds the entire free wheel together.
To tell the difference simply remove the wheel from the bike and spin the cogs. On a cassette the lock ring will move with the cogs. On a freewheel the lock ring will remain stationary, the cogs will revolve around the lock ring. Simple!
"I do whatever my Rice Cripsies tell me to!"
I'm only familiar with Shimano free hubs but it sounds like the middle cog is made to be connected to either the inner or outer cluster in order to hold it on there. With not enough support around the center of it (it must have broken loose) from the cluster it was connected to. If you know someone with a welder or brazer, you might be able to tack or braze it back on the cluster that it broke off of and not put any real money into a bike to just ride to the park. You'll have to see where it was attached originally though.
Any pic's of that "thing"?
Sure you can. $10-15 will get you one of these:
Originally Posted by package81
However! You need to buy the correct number of gears. (The above comes in 5-, 6-, and 7-speed variations). You need a special tool to remove your current freewheel. And freewheels are notorious for not coming off easily. Sometimes you must destroy one to remove it. Thus, if you're not already into working on bikes as a hobby, it might be easier and quicker to just run the bike into a bike shop and pay them to make the repair.
If you've already gotten your freewheel completely removed, then you're ahead of the game. You can get by without the tool. Just screw on a new freewheel hand tight and ride. The pedaling will tighten things up as firmly as if you had used a wrench.
I guess whether you do it yourself or pay a shop just depends upon how mechanically inclined you are. I had a friend who is a doctor who lost his umpty-dozen freewheel bearings in a field when the thing came apart on him. He bought new bearings, tore down the freewheel, and rebuilt it. Go figure.
Hec yeah, for that price why bother scewing around with it. Slap a fresh one on instead.
The biggest difference is that it will still screw on to external threads of the hub. And technically "freehub" is a Shimano registered trademark. It's basically just a proprietary freewheel.
Originally Posted by package81
That is a standard multi-speed freewheel. Easily replaced. And the good thing is that pretty much anything you can by aftermarket will be higher quality then what's on there. You should be able to take it to the LBS and get running for less then 30 bucks.
Originally Posted by package81
I'd just go ask in the 29er forum. Most bike in the same price range will be fairly similar. It's a bit of a Ford to Chevy comparison. The BIG brands tend to have better frames and the smaller guys will have better parts. I don't shop for bikes much, I just put them together and happened to have some bad experiences with GT lately.
Originally Posted by package81
I will say that the "triple triangle" design making any noticeable difference is probably more marketing and salesmanship then anything. Most bike will come with a pretty standard fame warranty so it shouldn't matter anyways.
The 1.0s I got were poorly assembled from the factory. Not a big deal if you were to buy it from me, as my company has very high new bike assembly standards and I will make sure that are perfect when they hit the floor (even if it costs me a hundred bucks a bike ) but I bet I could go into an IBD and find one with issues.
I haven't gotten an 2.0s so I can't say anything about those, but GT has been dropping the ball.
Like I said, go ask in the 29er forum, they will have a better idea of the good deals but I bet you could get a nicer bike for less money if you do some shopping.