mikjames

I hate skipping/choppy gearing with a passion. The local bike shop basically gave up on the bike because the rear derailleur is permanently bolted to the frame...with a flimsy aluminum bolt. It's constantly falling out of alignment, to the point where I need to adjust the fine tuner before every ride. That only minimizes the skipping though, it goes into hiding, waiting for the perfect moment to throw me off the pedals while I'm standing up, trying to climb a hill. Is there any way to salvage this? Would converting it to a 3 speed or 7 speed solve the problem? I'd be willing to do either one. It's not a terrible bike in general, I like the height of the frame combined with the 29" wheels. The weight is good. All in all it's alright for the light/moderate city trail riding that I do. I don't need disc brakes, the lightest strongest frame, or whatever else goes into the 1000$+ 1-7 speeds from the "premium" manufacturers. I appreciate the value that made in china offers, I just want steady gearing.

rebel1916

There is no value to a bike that doesn't work. One of those $300 rigid Diamondbacks from Dicks would do the trick. Or a mid level older XC bike.

mikjames

Yeah, I know that. There is nothing wrong with it aside from the gearing issues, and I don't need 21 gears. So I can either gather some useful input on which setup would be more likely to fix the problem (ditch the rear derailleur or the front, 3 speed or 7?), or I can just experiment and figure it out for myself. I live in Canada, so most of what you recommend isn't going to be viable or a good value. Chinese products are exponentially cheaper here than American imports. Canadian options are few and far between. I hope this clarifies my goal so that we can get back on topic. I don't want a new bike, I want to repair what I have. The bike is functional, let's focus on improving the functionality.

fietsbob

What is the tooth counts of the cogs and chainrings?

Did you learn to do math to calculate ratios ? the crank number turns the hub number in a gear ratio..

what are those ratios?

mikjames

Nope, don't know much about any of this. The only lead I have from the bike repair shop is that the rear derailleur is loosely attached, constantly going out of alignment. So my guess is that it needs to go. The problem is that leaves me with a 3 speed, where I'd prefer a 7 speed. I'm hopeful that I may be able to bypass/remove the rear set and upgrade the front set of gears. Is that a common modification around here?

Retro Grouch 

Cut your losses.

alcjphil

Your derailleur can be replaced, the bolt attaching it to the frame can be removed and it is possible to purchase a better one. You have a run of the mill Shimano Tourney derailleur. It can be changed for a higher end Shimano derailleur

rebel1916

If the problem could be rectified by putting a better bolt on, a competent shop would have done that. Try a different shop. Try a new rear derailleur. If that doesn't solve the problem stop shifting the rear and only use the front derailleur.

Doug64

Most derailleur hangers on aluminum frame bikes are made to break if the derailleur is impacted, and are replaceable. Is it the bolt(s) holding the hanger to the frame that come loose, or is it the bolt holding the derailleur to the hanger that comes loose? You can keep the hanger to frame bolts tight by using a blue Locktite. You may have stripped threads on the frame or the hanger.

Rajflyboy

VegasTriker

I looked up your bike online and it is a Canadian Tire exclusive priced at $400. It is a one-size-fits-all with only one frame size so you must be lucky to be the one person who actually fits the bike. It didn't take much time reading the reviews to find your problem. It gets a 2.3 out of 5 stars at the Canadian Tire site. There are three reviews. Two are titled "Disappointed" and the third says "Almost Perfect". Both of the "disappointed" owners write about the lousy gear system. Complete with misspellings:

mikjames

Lol, I didn't bother with advanced math in high school, didn't bother with the money sink of university either. Not particularly relevant given that I don't care enough to learn about gear ratios either way.

mikjames

I don't see any way to remove the derailleur without damaging the frame. It isn't just bolted on with a removable bolt, it's welded to the frame. Replacing it wasn't an option, and the bike shop is certainly willing to take my $ to upgrade various other parts. I don't have any money into this bike, so I guess I'll just get rid of it. I don't want to make the same mistake again though. What should I know about 21 speed vs 7-10 speed options? Is one typically more reliable than the other for smooth shifting?

alcjphil

21 speeds means that you have a rear derailleur with a 7 cog freewheel or cassette along with a crankset having 3 chainrings. For the most part today, bikes with "21 speeds" use very low quality components. Fewer "speeds" might well mean even cheaper parts and poorer quality. I find it very hard to believe that your rear derailleur cannot be replaced. I have worked on various bikes for over 40 years and have not yet seen a rear derailleur that was welded onto any bike frame. Find a better bike mechanic

rebel1916

That makes you especially unqualified to come up with a plain to rectify your situation. Your situation is probably unrectifiable, but even if it was, you would not be the man for the job.

02Giant 

How does that go? A picture is worth a thousand words...

Kapusta

AlmostTrick

Same here. I've worked on plenty of the lowest end Walmart bikes (like $89 'full suspension' 21 speeds ) and all had removable derailleurs. And I was able to get all to shift at least 'so-so', where one could get every gear and not fear dying from a dropped chain or missed shift.

AlmostTrick

I think new members need a minimum of 10 posts before they can post pics.

WizardOfBoz

This bike seems to be the very definition of a Big Box "Bicycle Shaped Object". Reminds me of Craftsman tools as they evolved: Lots of features, none of which work very well. Or the features worked but the tool function sucked. But you seem to have considered this and made a rational (if not hopeful) choice. In any case, your next choice is whether to invest in fixing a bike where other parts and features may break or stop working. It may be a situation of "no choice" in that you don't have money for a new bike (or at least, you don't have money for a new bike that's much better than this one and won't have the same problems). But if you fix the RD, the fork may start leaking. etc. Still, you may want to try it: the bike fits and has worked pretty well.

If you decide to give it a shot, know that nothing is "permanently bolted". That's an oxymoron! By definition, bolts come out. If the bolt has been fixed with loctite you can heat it a bit to remove it. Worst case, you can drill* a bolt out and chase the threads. But I'd remove the derailleur, check the hanger alignment, and either replace the RD with a new one or try the old one.

*Really worst case: you use something called Electrical Discharge Machining (EDM) to erode the bolt out. But that's on another level of cost.

Rajflyboy

rollagain

I looked it up and happened to see a list of features, including "steel V-brakes". Another victim customer complained that theirs broke twice in six days and that Canadian Tire wouldn't refund their money but said they'd "fix it."

IMO, the only "fix" for this thing is very big and noisy and operates at somewhere above 3000 degrees F.

Cut your losses now, and don't even ride it again; it's hazardous.

I feel badly that this happened to you.

BlazingPedals

Considering it's a high-priced BSO, almost anything could be wrong with it. If the frame isn't bent, you could replace the rear derailleur. Or the freewheel. Or the chain. Or the shifters. They're all standard parts, if cheap. "Cheap" as in "sucky," not as in "inexpensive."

Is the chain long enough to go around the big/big combination without bending something?

mikjames

Yeah now I'm remembering other problems with it. The brakes haven't failed after a summer of riding, but they are loose on either side of the tire, so it's half braked most of the time.
This isn't my first time on an internet forum. I'd really appreciate it if we can cut past the elitist forum bashing and focus on the facts though. I started this thread because I want to learn what is causing the problem, and how to avoid it in the future. It looks like I'm going to be replacing the bike. So getting back to the task at hand, where does this problem typically arise from? Is it typically an issue with the rear 7 speed derailleurs, or the front 3 speed derailleurs?

My initial assumption is the more cogs you put on a gear set, the higher the margin for shifting errors. Is that an accurate starting assumption folks? I imagine it is even more complex when you need to align 2 sets of cogs with each other. Single speed is simply not an option for me, and 3 speeds probably isn't enough either. I want a new (or slightly used) bike that I can get over the local hills with. So what should I be looking for? Should I avoid anything with a rear derailleur, front derailleur, multiple cogs, greater than 5-6 gears per cog? Is it better to have 2 cogs with 3-5 gears, or one cog with 7-10? I'm here to learn what to buy, not just to learn all the specifics of why my particular bike is garbage.

Aubergine