JohnnyB65

OK so I’m just learning on a used big-box store 21 speed mountain bike and I’m having some trouble shifting and turning. Now I know you all are going to tell me to spend a lot of money on another bike, but that is NOT going to happen at this point. So please I just don’t want to hear it because I am not racing, mountain climbing or anything that I even need gears for plus I already know I have the wrong bike, but it was free.

I paid a bike shop to go through and tune-up my free bike so I think it might be me that’s the problem. First off is my turning which is rough and I think it might be the fat dirt tires. I’m not sure if that is normal.

And secondly is my shifting. I’ve never ridden anything over 10 speeds so I looked on YouTube to see how to shift. I believe I only need medium on the front and maybe 3rd, 4th and 5th gear on the back according to the video. The problem that I’m having is that it freewheels between each pedal cycle even though I think I’m constantly pedaling without hesitation. Each time it catches up, the gear sounds like its slamming.

The shop put on a new chain and said they took it for a ride before giving it the OK. So is this normal? I don’t remember this ever happening on my old 10 speed.

caloso

I'm not sure what you're saying here. Are you saying that when you change gears, it takes a full pedal rotation before it engages? Or that it does that on every pedal rotation?

VegasTriker

You have way more than enough posts to add a picture of the bike and describe the components. Right now you have the blind leading the blind. What type of shifters (brand, model, type)? It could be anything from the shifter itself to the components on the rear wheel (freehub) or just a maladjustment of the rear derailleur which can be fixed by adjusting the tension on the shift cable.

You didn't know enough about bike mechanics to go through and adjust the bike yourself after you received it. You may have to rely on websites like this one Articles About Bicycle Repair for a tutorial. Bike repair and adjustment is not rocket science and DIY means a lot of $ saved plus if you are reasonably competent it will get done right.

JohnnyB65

Ok let’s see if I can say this differently. Forget about shifting because it does not happen when I shift.
It only happens while I am pedaling at a constant rate on level ground and not hesitating. The wheel speed seems to change momentary between each rotation as if I’m missing a couple of teeth. It only happens when my right foot is going down and my left is coming up. I don’t know maybe its just me.
I paid a guy to adjust the detailers so I don’t think that’s it although I guess I could take the bike back to him to check it out

caloso

Is the chain jumping?

JohnnyB65

I'm not sure, but I don't think so. it just seems like it's momentary freewheeling and then it catches with each complete rotation. It's just annoying because I don't know why and there is a lose of power.

If it were belt driven, I'd say it was slipping.

BlazingPedals

Here's a couple of guesses of what's happening.
1. your pedaling technique really is so bad that one leg is reaching the bottom of the stroke well before your other leg is ready to start pushing. I think this is unlikely.
2. the freewheel is slipping. This can happen when old grease hardens and the pawls inside the freewheel hang in the disengaged position.
3. the derailleur is between gears. This would be accompanied by a lot of clattering even when it engaged and you'd be going up and down a gear constantly.
4. A tight link can cause the derailleur to disengage occasionally. To check for one or more tight links, slowly backpedal with your hands while you watch the rear derailleur cage. A tight link will make the cage 'jump' and you'll see that it doesn't wrap around the pulleys the way the rest of the chain does.

The steering could be lots of stuff, too. If you pick the front end off the ground, does the steering turn easily from side to side? That can rule out tires. Next, does it feel rough or have a detent? The headset could be too tight, it could be dry, it could be worn out, or it could be just plain junky and incapable of working well.

Your free bike already isn't free, just be careful to not spend more fixing it than a new dept store bike would cost.

caloso

I might think it was a broken pawl inside the hub, but usually with that, once you've engaged a good pawl, it stays engaged until you freewheel again. If you pedal steadily, there shouldn't be the repeated slipping.

JohnnyB65

I’m not sure how the freewheel works, but the bike has been setting for 10 years. The bike shop did replace the chain because it was rusted and I don’t know if he took the axel and sprocket apart. This sounds more like it might be the slipping problem.
The first thing the guy told me when I brought the bike in was that the front fork was backwards which he fixed, but I don’t know how much he took apart to fix that and they don’t seem to have any play or too tight.
The tires weren’t worn at all and still had those little rubber hairs or whatever they are called and he did true the wheels so there are aligned. When I’m turning it feels like the tread is slipping on the pavement causing jerking making it hard to turn.
I saw my bike at Walmart for $140 and $80 on Crags List. I should have went to Walmart before taking this bike to the shop because I could have got one without all these gears that I’ll never use and a large handle bar for less than a $100.

Machka 

Sometimes, if you just put on a new chain without replacing the gears, you can get problems like that.

Please post a photo of your gears, one that shows the teeth nice and clearly.

JohnnyB65

I can't upload any photos because it says a "security token" is missing. I might try to upload with my desktop later when my system scan is finished.

Oh I just took a good look at the sprocket and it looks pretty dirty. I think I may have gotten ripped off by the bike shop and I'm going to call them in the morning.

JohnnyB65

OK so I just watched a few YouTube videos on freewheel repair and I’m positive that this is my problem.

I did not want to get into it this far and this is why I took it to the shop in the first place, but I guess I’ll have to now that I’ve lost confidence in the shop. I’m definitely not going to give them any more of my money if they overlooked this.

As far as the tires and steering goes, I can live with this as long as I’m not flying down a windy mountain road and maybe it will be OK after they wear a little.

So anyway thanks everybody for pointing me in the right direction.

JohnnyB65

I guess I have to remove the wheel to find out if I have a freewheel or a cassette.

wphamilton

Just about positive it's a freewheel. Not much wear on it either.

You said it only happens on the right foot, not the left foot. If that's true, I can't think of any freewheel malfunction to cause that. In the crank area, if the crank axle is wobbly in the bottom bracket, that might be a problem that could occur on one foot, but I think you'd notice that.

I'm speculating that it really does happen on both feet, but you only notice it on one due somehow to your pedaling, because other than that it does sound like the freewheel. I've seen it before, I think it has to do with old grease on the pawls and it lines out after awhile. I'd say ride it some more, try to be smooth with the pedal stroke and see if the problem goes away.

LesterOfPuppets

One other possibility is that the bottom bracket bearings are misadjusted or otherwise out of whack. That gives me the feeling that I think you're trying to convey.

To check for that, shift into the small chainring with the front shifter, take the chain off of the little ring and let it rest on the BB shell. Turn the cranks by hand to see if there is resistance.

Oh, and yep, that's a freewheel.

JohnnyB65

That is kind of funny, but you are probably correct. My legs don’t work that great these days. I plan on riding every day and I probably should give it more time before I start tearing things apart.

JohnnyB65

Thanks, I'll check that out tomorrow

VegasTriker

Now you know that "free" can be awfully expensive. I was asked this past Sunday about replacing the components on a bike like yours by a friend. I told him not to bother as it wasn't worth the cost of the components even though the bike was free. That's doubly interesting because he was riding a decades old Bridgestone RB-5 road bike that I refurbished. I saw the RB-5 at a local garage sale for $7. The tires were old, the bike was dusty, but I could see the bike hadn't been misused so I bought it. I went through the bike, made adjustments, lubricated bearings, and replaced the tires, tubes, and brake pads. I sold him the bike for the cost of the bike and replacement parts, about $50. He's still riding it a couple of years later. If you start out with a decent bike it is worth the trouble but I wouldn't touch a box-store bike.

JohnnyB65

I rode about 5 miles this morning and I suspect that I may be riding in the wrong gear. I'm still learning how to shift this 21 speed and I wish I still Had my old 10 speed. I know I have the wrong bike for me, but I don't want to spend the money if it doesn't work for me because then I'll have 2 bike to get rid of. I still have a long way to go.

Plus I didn’t realize it but the road is a little inclined and the bike maybe rolling faster then I’m pedaling. I also noticed that my left leg gets tired before my right and I only think I’m pedaling the same with each foot. I also have my seat all the way down so I can get on and off without falling and I will probably have to raise it after I master throwing my leg over the seat.

I paid more attention to how my tires make turns this time around and I believe its just the way these 10 yr old downhill treads ride on pavement. My last bike over 40 years ago had narrow smooth tread and the only time I had a problem was making a turn on sand covered pavement. I’m just going to have to get used to it for now. I was also watching how my wheels rotate as I’m riding straight and they do not bounce or wobble from side to side so I believe they are adjusted properly

What can I say it’s been a long time since I’ve ridden a bike and never rode anything like this one. I’m a little embarrassed to even have posted this, but I did learn a whole lot. Thanks!

u235

The bottom bracket could be twisted or the crank hole machined wrong (or stripped and widened) causing the cranks not to be exactly 180 degrees apart. I had that on a bike and to be honest I thought something was strange but really did not notice until I got on another bike. I guess I adapted. Close to what you described. It causes a dead spot and the drivetrain can slack for a small period.

Maelochs

For $85 or $90 you can get a Walmart Mongoose Hotshot which has gears but no suspension front fork, has a cassette, and is basically as cheap as a bike worth paying money for is going to be unless you are a mechanic.

Every penny you spend on the bike you have .... well, you have no idea what else might turn out not to be functioning or about to break. I might take on the bike as a project because I could do the work myself, and pick up dumpster bikes for parts, maybe .... But you will be paying for new parts for a beat bike.

Also ... those knobby tires will make you a little unstable on the pavement, because when you lean into a turn you are putting all your weight onto a very uneven surface.

LesterOfPuppets

Performance bike was blowing out their Fuji 26ers a little while ago. Aluminum frame, XCM fork, Altus shifters/Acera rear derailleur. Pretty nice bikes for $229. Looks like they're all gone now, though.

JohnnyB65

I’m a little upset that I didn’t think this out more because it cost me $80 for the tune up including a new chain. And then I had to spend another $25 to replace a seat for a bike that is not really suited for me.
If I can ride this bike every day for about 4 months while getting stronger and be able to ride farther, then I will buy a new bike that fits my needs at that time. Who knows maybe by that that time, I’ll be ready for some serious riding and want a completely different style of bike.

Maelochs

Well, I almost always recommend a Nashbar flatbar road bike at this juncture ... but that costs three times what the Mongoose costs.

Normally I would never recommend a Wally-bike to anyone I didn't hate completely ... but I have a friend whop bought one and seems satisfied.

For people who don't ride much, don't ride hard, but might want more than one gear and maybe want a rack for groceries, the Mongoose seems like the minimum. It has a real cassette and freehub, seven speeds out back and nothing up front (simple enough for novices, and for anyone who doesn't plan on competition or live in the mountains (or San Francisco) and is basically 30 lbs of steel with some 28-mm tires.

For someone who barely pedals, doesn't plan to grind down curbs or get big air .... and wants to spend basically nothing or close to it ... and doesn't want to have to do much adjustment .... (not much to adjust ... )

If the OP wants the baseline Real bike, he is looking at over $200 and probably $300 or he will be wasting money on something not much better than the Mongoose.

IMO.

MRT2

If you got the hang of shifting with your old 10 speed, you should be able to shift your current bike. First of all, it isn't a 21 speed, it is a 3 x 7. 3 chainrings up front, and 7 cogs in back, which is only 2 cogs more than your old 10 speed, which was a 2 x 5. Now, the small chainring is likely a very small gear, so for now, forget about that one and focus on the other two chainrings. Start out using the middle chainring and leave it there until you get the hang of things. Now, when you start pedaling, shift into a gear that allows your legs to spin the pedals at about 80 to 90 rpm and still feel some pressure. If you are pedaling like crazy and not feeling any tension, than shift to a harder gear. If the pressure is so great your legs are getting gassed or you cannot maintain at least 80 rpm, shift to an easier gear. That is it.

As for the tires, those knobbies are poorly suited for paved surfaces, so if you keep this bike, you need to budget $40 to $70 for some new tires. That free bike is not free and not worth putting any money into. an expensive lesson, but maybe it is time to consider cutting your losses and starting over.