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GMC Denali bottom bracket and headset replacement?

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GMC Denali bottom bracket and headset replacement?

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Old 03-17-19, 06:54 AM
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GMC Denali bottom bracket and headset replacement?

Hi all, I have one of those el cheapo orange GMC Denali road bikes (22.5" model). I put about 3000 miles on it last year and totally wore out the bottom bracket and the headset. I do not know much about bikes and my LBS recently went out of business. Does anyone know what replacement parts would fit?

After reading the forum for a bit, it seems the common consensus is to to just buy a higher end bike instead of repairing the Denali. However, I want to repair this bike because I plan to use it to commute to college where bike theft is pretty rampant. I got hooked on road biking with this cheap bike last year so I plan to buy a better bike in a few weeks but I do not want a $1500+ bike to get jacked.
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Old 03-17-19, 07:02 AM
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From the video description:

The box that my new BB came in states the following sizes: 68mm BSA and 122.5mm. I believe the first number is the length across the bottom of the frame's bottom bracket tube and the second number is the shaft length. Note that the original bottom bracket on this bike has a shaft slightly longer than the shaft on the replacement BB that I used, but the replacement worked just fine. The exact model information listed on the box above the barcode is "BB-UN55 122 BC137 68" Hope this helps.
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Old 03-17-19, 07:25 AM
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BiggFred
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Too expensive to fix?

You will be told to get a different bike from pretty much everyone, and they’d be right. But you made your point about riding it to school, so I get that too.
My guess is that you wouldn’t be changing the bottom bracket or headset yourself so you would have to source parts and pay for labour. I think your best bet, if you like the bike would be to buy a new one. They have it at Walmart for $199 and free shipping (I’m assuming you are in the USA). https://www.walmart.com/ip/GMC-Denal...White/49590912
This bike is pretty crapy. but if it serves it purpose for what you need, then that’s all that matters. I couldn’t find any info on the quick search I did for bottom bracket and headset info.
You may be better off looking for something used on kijiji.
Also there could be cheaper prices for this bike too, but at least you can return it easy to Walmart if it has any issues. Good luck and get yourself a real bike too.
check out these discount bike sellers for other options too.
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Old 03-17-19, 07:38 AM
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Originally Posted by SpandexSpeeder View Post
Hi all, I have one of those el cheapo orange GMC Denali road bikes (22.5" model). I put about 3000 miles on it last year and totally wore out the bottom bracket and the headset. I do not know much about bikes and my LBS recently went out of business. Does anyone know what replacement parts would fit?

After reading the forum for a bit, it seems the common consensus is to to just buy a higher end bike instead of repairing the Denali. However, I want to repair this bike because I plan to use it to commute to college where bike theft is pretty rampant. I got hooked on road biking with this cheap bike last year so I plan to buy a better bike in a few weeks but I do not want a $1500+ bike to get jacked.
I get it. I did this to my Denali. But I will say, even if you do the work yourself, you still need at minimum a crank puller and bottom bracket tool. The head set tool you can make yourself from some nuts, washers, and threaded rod. Just be aware that you won't be saving any money, in fact you'll most likely lose money doing it. From experience, if money is tight, I second just getting another cheapo- even another Denali since they actually do just fine for campus commuting- until you're in a better position to upgrade.
That being said, yes, it takes a 68mm English threaded UN54 bottom bracket and I think it's a 1 inch threaded head set if you're not boing to upgrade the stem and bars.
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Old 03-17-19, 08:03 AM
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Bike not worth the time energy or money to repair.
get another
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Old 03-17-19, 08:13 AM
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Originally Posted by BiggFred View Post
You will be told to get a different bike from pretty much everyone, and they’d be right. But you made your point about riding it to school, so I get that too.
My guess is that you wouldn’t be changing the bottom bracket or headset yourself so you would have to source parts and pay for labour. I think your best bet, if you like the bike would be to buy a new one. They have it at Walmart for $199 and free shipping (I’m assuming you are in the USA). https://www.walmart.com/ip/GMC-Denal...White/49590912
This bike is pretty crapy. but if it serves it purpose for what you need, then that’s all that matters. I couldn’t find any info on the quick search I did for bottom bracket and headset info.
You may be better off looking for something used on kijiji.
Also there could be cheaper prices for this bike too, but at least you can return it easy to Walmart if it has any issues. Good luck and get yourself a real bike too.
check out these discount bike sellers for other options too.
Road Bikes | BikeShopWarehouse.com

Save up to 60% off Road Bikes, Free Ship 48, Schwinn, GT, Kestrel, Fuji, Motobecane and more Road bikes. Authorized dealer for Schwinn, GT, Kestrel, Fuji, Motobecane, Mercier, Gravity, Dawes road bikes. Shimano Carbon Road Bikes, Titanium Road Bikes,



My kids went through 4 years each and one of them in 4 years of grad school with old high quality racing bikes. They're only worth about $300 or so but they hold up amazingly well and are not a theft target like newer bikes. A good U-lock used properly and some security skewers and it's never a problem. Both of these bikes were both in universities in major urban areas. These were some of my old bikes that we had kept through the years, but you can find these all over on Craig's list, FB Marketplace or from those bike shops that recycle old bikes. These were bikes that had hand built wheels from the day, 5 or 6 speed cassettes, friction down-tube shifters etc... A side benefit is that they accept wider tires easily so it was simple to put on durable tires that could handle road defects etc...

That would be way smarter than putting money into a Walmart bike or even fixing this GMC thing. That bike would easily last your entire academic career. My son's bike (he's in school for a PhD) has been going 8 years now and hasn't missed a beat. That's a 1980 vintage Motebecane with that very low end campy drivetrain that they offered and handbuilt wheels on campy hubs.

j.
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Old 03-17-19, 10:36 AM
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Thanks for the response, mynewnchome. I found one on amazon for $22 along with the crank tool for a few bucks more.

But I honestly can’t tell if you guys are trolling or not with the “buy a new bike thing”. I don’t have an issue buying a $20 part and a few tools to do it myself. At the very least I see no harm spending an hour or two learning a new skill. I do have an issue with tossing out a bike that can be repaired let alone one that could get stolen/parted out when parked on campus.
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Old 03-17-19, 11:19 AM
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It all depends on your needs and wants. Whatever works for you.
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Old 03-17-19, 07:00 PM
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Made up of nothing weird , just got the cheapest of the parts available , ..

you need to buy thevtools and then similar parts , which will probably be better

ignore the voice in your head saying, " but it cost more than I paid for the bike" (or Not)

Of course it did, you bought a low cost bike .. it's a sum of it's parts ....





...

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Old 03-17-19, 07:21 PM
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Originally Posted by SpandexSpeeder View Post
Thanks for the response, mynewnchome. I found one on amazon for $22 along with the crank tool for a few bucks more.

But I honestly can’t tell if you guys are trolling or not with the “buy a new bike thing”. I don’t have an issue buying a $20 part and a few tools to do it myself. At the very least I see no harm spending an hour or two learning a new skill. I do have an issue with tossing out a bike that can be repaired let alone one that could get stolen/parted out when parked on campus.
i think you’ll find that your bike won’t fare well being out in the weather when you leave it on campus. Cheap bikes rust faster and have less
eobist parts and are made fraterials that don’t weather as well. Walk around a campus and look at the bikes in the rack and you’ll be able to tell that easily.

A bike for an undergrad without a car becomes sort of a mission critical piece of equipment. If it doesn’t work right, it’s worth nothing and becomes a huge hassle. Eventually it will be like all the other abandoned cheap bikes you’ll see.

But whatever “turns your crank”. Just giving you the benefit of our 12 student- years of experience with bikes on urban campuses in a northern campus subjected to all kinds of weather. . Used is a huge bargain and far better than what you have there for marginally more money.
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Old 03-18-19, 04:56 AM
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Originally Posted by SpandexSpeeder View Post
Thanks for the response, mynewnchome. I found one on amazon for $22 along with the crank tool for a few bucks more.

But I honestly can’t tell if you guys are trolling or not with the “buy a new bike thing”. I don’t have an issue buying a $20 part and a few tools to do it myself. At the very least I see no harm spending an hour or two learning a new skill. I do have an issue with tossing out a bike that can be repaired let alone one that could get stolen/parted out when parked on campus.
You'll also need a lock ring spanner.
Park Tool (109917) HCW-5 Lock Spanner
https://www.amazon.com/dp/B000C17KRI..._MH3JCbJ16KMHR

And an installation tool for the bottom bracket, if you got a sealed beating cartridge style.
Bikehand Bike Bicycle Shimano Bottom Bracket Removal Remover Tool
https://www.amazon.com/dp/B00811WQJS..._YK3JCbCQSXAEK
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