Something wrong with hub or chain or derailleur

[orvn]

Hi!

I've got this new bike which was poorly put together as a show model at a retail location.

I trued and adjusted the brakes to my liking as they were barely functional and tightened a variety of things, but I'm not sure what's wrong with the derailleur/chain/hub, I'm pretty sure it's something basic, so bear with me here.

When I rotate the pedals clockwise (with the bike upside down), simulating forward pedalling the wheel moves, however, when I mount the bike and pedal forward, I get ahead and then I feel the lack of force and stop moving- as though the chain slipped off. After a few rotations it catches on again resulting in the bike moving forward.

Moving the pedals backwards results in a strange noise that isn't just the clicking sound of the freewheel, it sounds a lot more like something rattling (along with sporadic freewheel clicking). All in all, the bike feels pretty unstable and unridable because of this.

I'm not sure what's wrong or what I need to do..
is the cassette not properly attached to the inner part of the hub?
Or is it something with my chain and derailleur?

I really have no idea, although I'm willing to learn, deduce and solve the problem.

Also, I know my description was poor in some areas, so he's an equally poor video:
http://searchanddevelop.ca/dump/yellowbike.mov
searchanddevelop.ca/dump/yellowbike.mov

Note how the chain or freewheel seems to skip.

Any suggestions?

[Painkiller]

first off, I am not a fan of working on bikes upside down. hang the bike somehow. a tree branch and a couple belts or rope. make sure your derailleur is set right. If it is and you still have the problem. swap wheels if you can and see how the bike acts. If it seems better your free wheel has an issue. put your wheel on another bike and see if it acts bad then you will know for sure.

[orvn]

Thanks for the reply, I'm sort of in an apartment building, leaving suspension options a little limited- I'll try to figure something out though.

I think I'm going to need a tool to take the hub off and switch the wheels that I don't have, right?
I may have another 12 speed bike I can do the substitution with.

I'll take some photos while I'm down there too.

[nfmisso]

Sounds like the derailleur adjustment is not correct; and thus the chain is not in the correct location with respect to each cog. B screw; high and low limit screws need to be adjusted, and the cable length fine tuned.

As PK said, get the bike right side up. This is the bike stand I built: http://forums.bikeride.com/thread-3168.html very inexpensive.

Also, in the video you have the chain in the smallest cog at back and the smallest ring at the front - avoid this combination, as well as the largest front and rear.

This bike has been around a long while (several years; probably more than ten) as it has a six speed freewheel. Take the rear wheel off; and drips some oil into the gap between the moving part and non moving part of the freewheel.

All the bearings (both wheels, headset, bottom bracket and pedals) probably need regreasing also.

Take a look at Alex's videos on this site.

[Painkiller]

lets see some pics, could not tell much from the video. but it probably is a freewheel/cassette issue. do you have a warranty?

[orvn]

I think I might have a one year manufacturers warranty, but I'd have to ship it and specify the defect. I believe I just need to adjust the derailleur now.

Also the protective disk between the spokes and hub is plastic and rubs against the spokes a lot.

Here are the bike specs:
Frame: Alloy
Size: 56 cm
Fork: Steel 1-inch threaded
Shifters: Shimano stem-mounted SIS lever shifters
Stem: Steel 22.2 quilled
Crankset: Dotek steel double 52/48
Pedals: Plastic road pedal
Wheels: 700c double-walled alloy/steel hubs 36h
Tires: Wanda 700c/25
Derailleurs: Shimano A050
Handlebars: 42cm 25.4 classic steel drop
Seatpost: Alloy 27.2 300 mm
Saddle: Steel rail road seat
Speeds: 12

And photos:

[ghost]

Your freewheel is shot and that means a new one. The protector is only there the stop the chain dropping into the spokes if the mech is over adjusted. Shimano still puts out in their site a 6 speed screw on unit. You will need a chain whip and the correct freewheel remover and Park tools and a lot of US companies make them.Good luck!

[nfmisso]

(09-26-2011, 06:41 AM)ghost Wrote:  Your freewheel is shot and that means a new one. The protector is only there the stop the chain dropping into the spokes if the mech is over adjusted. Shimano still puts out in their site a 6 speed screw on unit. You will need a chain whip and the correct freewheel remover and Park tools and a lot of US companies make them.Good luck!

I have to disagree - I do not see anything wrong with the freewheel in the video.

A chain whip is of no use in removing a freewheel. A freewheel removing tool (FR-1 for Shimano, FR-7 for Falcon - likely your is one of these two; after you removing the wheel from the bike frame, you should be able to read the writing on the freewheel); and a bench vice bolted to a very heavy table works best.

[ghost]

(09-26-2011, 11:30 AM)nfmisso Wrote:  

(09-26-2011, 06:41 AM)ghost Wrote:  Your freewheel is shot and that means a new one. The protector is only there the stop the chain dropping into the spokes if the mech is over adjusted. Shimano still puts out in their site a 6 speed screw on unit. You will need a chain whip and the correct freewheel remover and Park tools and a lot of US companies make them.Good luck!

I have to disagree - I do not see anything wrong with the freewheel in the video.

A chain whip is of no use in removing a freewheel. A freewheel removing tool (FR-1 for Shimano, FR-7 for Falcon - likely your is one of these two; after you removing the wheel from the bike frame, you should be able to read the writing on the freewheel); and a bench vice bolted to a very heavy table works best.

1. I do not know what type it is and .
2. Not everybody has a bench vise.
3. The video does not work on my computer