Sorry if this is the wrong area...

I have a mongoose xr-75, got it used a few years ago.
It's in fully working condition, but it is a bit worn out n rusty n weathered.

I want to start riding it on the road a bit but mainly these flat gravel trails my neighborhood has... it is kinda a fine gravel, been a while since i've been on it but I think the rocks where about dime sized.

low spec, new and pretty cheap parts.

the things that I would like to now/eventually get up to "low spec"

the seatpost is far too short for my long legs - $20
all the cables could be replaced - $???
some more onroady tires? 26x1.95 -$40?? pair
I cant quite remember if it was the cassette or the crankset that I saw some wear on, but both look to be in the $20 area
rims are kinda wobbly, idk if their cheap or not, to replace :/
derailers need tuning.

The brands that I see are giant for the seatpost and crankset
shimano for the cassette.
Giant K935 Comfort ATB Tire is a tire tread that I kinda liked, but didn't know how it would really perform for what I want.

are these parts worth it? how compatible are bicycle parts?
my priorities are:
seatpost (I found out the diameter, but need to check how much longer I need)
cables/derailer tuning, if its cheap enough.
cassette/crankset
tires, these will probably outlast the gears, but one is dryrotted, also wondered if I could put a slimmer tire in the rim 26x1.95 is what it has now, but when on road you can really feel the drag.
rims, a bit wobbly but not too much concern.

but then again... I can go buy a new bike for about $100
but I'd still need the seatpost, and tires, as I do like to do speed runs on the road.

Ask me anything, I would like to get these questions answered as best as possible.

Thanks,
Awaqa909

If you need a longer than stock seatpost, it is very likely that this bike does not fit you at all, and this alone makes it an inappropriate candidate to be a good bike for you. Couple the ill fit with worn parts, and the fact that it is a terrible bike to begin with, and you are on your way to the ill-advised-upgrade trifecta

Please don't think that I am calling it terrible because I dislike all box-store bikes, or that I subscribe to a minimum MSRP that must be met to get a bike worthy of my respect - these are not the case. The Mongoose xr75 is a singularly terrible bike - from the energy robbing sloppily manufactured suspension - front and rear - to the super low grade components selected so more money could go towards making it appear to be a decent bike, this bike is a loser in every way and you should not waste a single penny trying to improve it.

Lots of good used bikes available cheap. Much better value than either a cheap new one, or the upgrade you mentioned.

That's pretty disappointing to read that...
the seat is like a Schwinn high timber mens, while what I want is like a Schwinn rocket 2
Mountain | Schwinn Bicycles
are any of them good used bikes in the $100 range? ... I live Austin, Texas, USA...
currently I don't ride much at all, maybe 2-3 times this year, and probably did a mile out of all of them rides.
was hoping I could buy a cheap seatpost and get away with that for a while, find out if I enjoy riding a bicycle as much as I did when I was 8ish, 10 years ago.
and then maybe look into buying parts in previous post, and make it my own bike.
even if its a $100 bike I'm buying... I have a death grip on my money... and then if I didn't use the bike, it would just suck...

If you want to stick with a cheap mtb, find a hard tail or rigid, many users will talk spit all day about big box bikes, but honestly if you stay away from the full suspension bikes, the bmx bikes, and the Denali, you can have a decent bike. You can always put a rigid fork on a hardtail, and they really are just early 90s tech bikes.

Get a hard tail, I can tell you don't aspire to have anything but an okay travel bike, to which these bikes can be- if you pick the right ones. You already said you just want low end components, Shimano Tourney is the best of the low end crap, and most bikes unless "high end," 29ers, hybrids, and full suspensions, don't have them.

The flip side is take your $100 and look for a classic rigid mtb from the 80/90s, or road bike, that'll have have decent components or group on it, most of the time even the low end components on some of the bikes are better than the low end on todays low end. As long as you stay away from bikes like the Hard Rock, that are still nearly 400bucks for no reason at all- just because of the price, I say stay away, look for something like a diamondback Sorrento- which is just as good as a HardRock, and be had cheaper. Stay away from anything with side pull brakes.

I felt pretty understood right there!
don't laugh too hard but I kinda like this bike in some ways
Roadmaster Granite Peak 26" Men's Mountain Bike, Black - Walmart.com
Before I even consider laying down money, I would try to test ride or atleast give a good look over a display model.
not sure what kind of gears it really has, but upon youtubing it I saw what a guy did to it and liked it alot. I know some components are cheap, and may need to be replaced sooner or later or now. but does the frame angles n layout look similar or remotely like a high end frame? ... imagine it made and had the price of a schwinn or something.
most of my bicycles if not all have been under $100 and left in the front lawn out in the rain, and some served many years when I was a kid. (back then riding bicycle racing with neighbors was the thing to do, about 2007 is when the video games started taking off and taking time...)
I have yet to look on craigslist as it doesn't want to work.
but is it hard to find aftermarket parts that would actually fit a bike?

The troubles with that one are:
- the 6-gear rear identifies it as a freewheel rear hub. Those are inherently weaker than cassette/freehub rears. They have a longer unsupported part of the axle. Might be OK for either a lighter rider, or a very careful rider. But at average or above average weight, all it takes is a careless drop off a curb and you've bent or broken the rear axle.
At the very least,try finding one with a 7-speed rear. That way, if your rear wheel fails, you can replace it with a cassette wheel and still keep your current shifters. Or go for one with a 8/9-speed rear.T hat's almost always associated with a cassette wheel, and you get the stronger design from the beginning.
And while it might sound as bragging or elitistic, I sincerely agree with the statement that poor suspension is worse than no suspension.
It's heavy, and sloppy, and just doesn't work particularly well. Might soak up some vibration if you're riding on cobbles or crossing a rail/tram track but that's about it.
With a rigid fork, at least you have the pleasure of a bike that's reasonably responsive and consistent in its handling.



If you're just an occasional rider, don't worry about geometry. Almost everything is rideable. The body adapts.
While there certainly are differences, you need to be a something a lot more than an occasional rider before you can say with honesty that it's the geometry that's keeping you from doing this or that on a particualr bike.Worry a little about size and comfort though.


Not really. There are still plenty of parts available that'll fit a bike like that. But you can't count on a randomly chosen shop to have them at home, or be willing to mount them for you.

First off, don't spend any money on your current bike. Its one of the worst designs ever and apparently doesn't fit you.

One thing to consider is that department store bikes hold no value. If you buy a used bike of good quality and don't end up riding it much, you can resell it with little to no loss. If you've only ever ridden department store bikes that don't fit you, you may be blown away at what a reasonable bike will do for your enjoyment. I'd recommend you read a little about bike sizing, and buy an older bike that fits you. A rigid (no suspension) bike from the 80s/early 90s would be a good call. Also, if you ride any appreciable distance, a quality bike will be much cheaper to keep running.

A bike requires a fair amount of material with a lot of moving parts that need to meet fairly precise tolerances to work well. They require reasonably skilled assembly. The combination of features and price on department store bikes is just unrealistic. If you must buy a department store bike, I would advise first against suspension, and possibly multiple gears.

Also, upgrading parts is generally a poor plan. Markup on complete bikes is actually typically fairly low. In contrast, individual parts have higher markup. Its much cheaper to buy a bike of your intended target quality in the first place.

Getting a bike that fits makes riding MUCH less tedious.

"......as I do like to do speed runs on the road......"
"......currently I don't ride much at all, maybe 2-3 times this year....."

That kind of sends a mixed message-

You might describe your size and maybe one of us can help pick a bike on CL.

IF you are tall, this would be a good candidate, since it's old enough that Schwinn hadn't gone to crap yet.
Schwinn High Sierra

Stay away from any suspension unless you absolutely need it, which you apparently don't.

I would say worry a lot about size and comfort. The fit of the bike is the most important thing. If you can find a rigid box store bike that fits well then that will be OK. However, the vast majority of box store bikes only come in one size and this makes them a bad choice for anyone not of average height. The only one I can think of that comes in multiple sizes is the GMC Denali. THe Denali is mentioned somewhere else in this thread as a bad bike, but I disagree - because it is a rigid frame, it is a far better choice than any suspension bike. And I think you can get it is a couple different sizes.

This is a plus for searching for a used bike - there are all sizes available, although XL and XS sizes might be more rare. Figure out what you need and look for bikes that are likely to fit. A cheap bike that fits is better than an expensive bike that does not.

For starters - how tall are you ? You say you have long legs, but does that mean a 36" inseam but you are only 5'6"?

Well, the OP did say he was planning to seek a bike out IRL, which would give him at least something of a chance to judge fit before purchase.
But a pootle down the aisle or round the parking lot won't be enough to expose those weaknesses that are literally more likely to appear "further down the road", like a rear axle failing, or the floppy fork becoming apparent.

You didn't mention your age or size in height, but it sounds as if this bike doesn't fit you well. If you're young ( teens ), then you'll get taller. I'd suggest rather than sticking money into a bike that doesn't sound as if it fits your size correctly, and needs many parts replaced, sell this bike and get a bike you like that fits your body size in an appropriate manner, and can be used on the different road/trail surfaces you ride. There's nothing worse than spending money trying to get a bike to fit you when in 6 months, the bike will be too small again. Your money would be well spent on something you can ride and enjoy for a few years, instead of putting money into a bike for the next person. You'd never be able to recoup your expenditures on the current bike.

Broken axles and forks can be replaced. Fitting an 17" frame to somebody 6'4 is a more difficult problem.

...which he has a decent chance of finding out himself if he stays true to his intention of seeking a bike out IRL before purchase.

You should take your $100 and go buy this right now.

Schwinn High Sierra

There are at least a half dozen bikes in your price range on the Austin CL that are better than your bike will ever be. That's just the facts.

The nice thing about a second hand bike is that the bulk of the depreciation has already happened, and you can get almost everything back on resale if you decide cycling isn't for you. That is provided that the bike was decent quality to begin with. The problem with a sub $200 new bike is that its resale value is pretty much nil. If you can find a decent second hand bike for your needs it will probably offer much better value if you can find one in good condition. According to you, you plan on riding on surfaces where suspension is not only not needed, but probably a drawback. The suggestions of looking for an older, good quality, non suspension mountain bike are excellent

80's mongoose name got sold off , its not the same company anymore.

to get a better bike go get one at a bike shop not wall mart type box stores.


Maybe a 'Tune up' at a shop will help get it working better..

I'm not sure about having a rigid, in that craigslist post, but am still having issues with craigslist, I had to go though a proxy site to look a tiny bit. (I see many issue reports recent for my area of craigslist)
I kinda feel like i'm dragging this along... but if you total a wheel or something, how much is it to get a new one? rim, spokes, the thing the spokes go in? I've found cheap tires, freewheel, cranks... just about everything, but wheels.
I'm not quite convinced freewheels are worse then freewheel hubs... tried looking at diagrams was like they both have a similar sized shaft then the spoke thing... if I saw both in parts, in person...
would be nice if I could do some little stunts, and if I found a area to jump (I jumped this little ramp slightly taller then the curb/sidewalk and was very scary lol) not sure a rigid would suit that. I hope CL works soon so I can look for myself. was mainly interested in the wheel question.

Good question. Nobody has ever figured this out.

That was me, I didn't say it was a bad bike, I actually like them, if he's as big as he said he was(400lbs), he might not like it when it comes to use the brakes. Now if he's interested, the Genesis Roadtech is a better choice- I just bought one of these, the reason I said avoid it, is the price- it's a little over a hundred bucks, and the Roadtech was $210.98 after tax when I bought mine.

I'm not sure where the 400lbs came from? but im about 6' 2" long spined and about 140lbs, will check my inseam and height tomorrow.

It's pretty modern; vbrakes, a derailure(its that cheap no name below tourney one I was talking about) that is actually bolted to the frame, adverse to held one by the wheel, 3pc crank, I think iys a 48/38/28, or the next ratio set below that, 1" threaded headset. Roadmasters are actually a real common bike around here, it's modern enough to upgrade, they usually have aluminum double wall wheels, the spokes are bare or galvanised steel, though.

I would go for a hard tail mongoose with an element fork, and heres why; they have the best fork of all walmart suspension bikes, I'd still swap out for a rigid, but until you can: those forks act progressively, they stay fairly stiff, and soften as you ride across bumps, and stiffens as get back on solid ground.

My favorite hardtail- the only one I'd ever pick to ride with a *** to my head is the Research Dynamics Coyote. I had one and it was stolen, it's fork was insanely stiff, and never bottomed out, when it did give, it only had 3" of travel. I'm going to beat the guy who stole it. It was my size too, I stuffed an 8speed wheel on it and trgger shifters. Blah.

While there are oversized rear axles available, those go on bikes that are maybe 10 times more expensive than the one you linked to, if not more.
Most rear wheels share the same axle diameter.
But the key isn't in the diameter, it's in how much the sprocket stack overhang the bearing.
With a freewheel design, the inside face of the bearing sits pretty much flush with the spoke flange. The rest of the distance to clear the sprocket stack and to fetch up against the inside face of the dropout is taken up by spacers.
With a freehub/cassette design, the bearing sits something like 20 mm further out. Meaning it will be that much closer to the dropout.Meanin it'll need less spacers. Meaning it'll be a lot less bending force to deal with. Meaning the axle will survive better.
But you're right so far that it's the same principal design. The devil is in the details.

That Schwinn is sweet. If it were not 2000 miles away from me I would buy it. Absolutely a far far better choice than any X mart bike.

Putting aside the fact that it is not a 'modern' bike (18 speeds? 1" threaded headset?), and that it has absolutely no potential for upgrading unless you change every moving part on the bike, the Roadmaster suffers the same fatal flaw that makes the Mongoose a bad choice - it comes in one 'medium' size that will not properly fit the OP.