a 4 part question

[hedoe]

this is going to be a thread with 4 different questions in it, the will come when the previous one is answered
so keep reading each day
and ill even tell you the subject of each question
part 1: rear derailleur problems
part 2: tires and wobble
part 3: disk brakes
part4: after market items

Part 1: Rear Derailleur Problems
okay last week I bought my first dual suspension 21 speed mountain bike
and its been a while since I had rode a bike
but that’s not the issue
the problem is that my rear derailleur wont shift into 1st gear
no matter what I do
if I try and set it in the 1st gear, and the grip shifter is in 1st it will slip off into second
and when I’m in 6th it is in 7th
and then 7th gear is useless
I only have 18 gears instead of 21
which means that I got shorted
so what do I do?

 

[Scotty_Dog]

so what do I do?

I'm going to sound like a complete ass, but here goes:

Take that 50 pound, dual suspension beast back to Wal-Mart for a refund. I'm assuming it's a department store bike because you mentioned it's a 21 speed. If so, your list of problems is only going to get longer.

 

[hedoe]

holy F man!
how the.....
can you read minds or what?!
can you go into a list of as many problems as you can think of?
should i just replace the derailleurs all together?
lets just try to stay on topic here.
but thanks for the info

 

[Scotty_Dog]

http://www.parktool.com/repair/
specifically: http://www.parktool.com/repair/readhowto.asp?id=64

http://www.sheldonbrown.com/
specifically: http://sheldonbrown.com/derailer-adjustment.html

 

[hedoe]

http://www.parktool.com/repair/
specifically: http://www.parktool.com/repair/readhowto.asp?id=64

http://www.sheldonbrown.com/
specifically: http://sheldonbrown.com/derailer-adjustment.html

thanks for the links
still dancing around on the 1st question
even before I bought the bike I was thinking about changing some of the equipment
first of all I was going to have the frame powder coated (my mind is made up on that one, and has been for a long time)
so while it is disassembled I would change almost everything (I knew that just by looking at it)
I would to replace the crank wheel, arm and the pedals
while I would be in the area I would also replace the front and rear derailleur’s
I was thinking about getting the shimano XTR crankset and front derailleur
could I keep my current rear gears? Or do I need to get different gears for a different rear derailleur?
wow this thread is going to be long before all of my questions are answered
oh well thanks for the advise and bear with me, also I know .............
nothing (lets just say that) about any of my questions or have any knowledge of my choices or how to accomplish them
so if you could please be very detailed.
Thanks

 

[j.r.hawkins]

Don't want to sound cruel, but you get what you pay for.

Take it to the tip or donate it to charity, and then go buy something decent and secondhand that might be a year or two old from eBay.

With all the upgrades and options you're wanting to put on it, you will have spent much, much more than the cost of a new bike, and still have a heavy and weak department store bike with **** performance and no resale value. And that's if the upgrades you're wanting are compatible with your frame. (Think: bottom bracket, headset, rear axle spacing, stem, handlebar tube diameter, chainline).

The reason is the markup on aftermarket parts is two to three times or more than what the bike manufacturers pay.

On your first question, go buy yourself a copy of Zinn & The Art of Mountain Bike Maintenance. There you'll learn about setting the limit screws and then resetting cable tension, along with everythign else you'll ever need to know about maintaining quality bikes. A detailed set of instructions would take longer for me to post than it would for you to go get the book from Amazon.

 

[hedoe]

Don't want to sound cruel, but you get what you pay for.

Take it to the tip or donate it to charity, and then go buy something decent and secondhand that might be a year or two old from eBay.

With all the upgrades and options you're wanting to put on it, you will have spent much, much more than the cost of a new bike, and still have a heavy and weak department store bike with **** performance and no resale value. And that's if the upgrades you're wanting are compatible with your frame. (Think: bottom bracket, headset, rear axle spacing, stem, handlebar tube diameter, chainline).

The reason is the markup on aftermarket parts is two to three times or more than what the bike manufacturers pay.

On your first question, go buy yourself a copy of Zinn & The Art of Mountain Bike Maintenance. There you'll learn about setting the limit screws and then resetting cable tension, along with everythign else you'll ever need to know about maintaining quality bikes. A detailed set of instructions would take longer for me to post than it would for you to go get the book from Amazon.

okay forget about the bike for now
Part 2: Tires and Wobble
when I look at my tires I can see a definite wobble to them
at any speed
so my question is how straight are your tires? Do they wobble?
And how do I attempt to fix the problem?
Or is it just nothing but the rims?
Or is it the forks or what?
Thanks for your help so far

 

[Scotty_Dog]

okay forget about the bike for now

I simply can't do this...........

I mean, earlier you wrote about powder coating the (Wal-Mart) frame, and adding an XTR crankset and derailleurs. That's like applying 12 coats of PPG to a 1984 Yugo, and then slapping in a Ferrari transmission. You might be able to do it, but why would you?

so my question is how straight are your tires?

They aren't straight at all. In fact, they're round.

Do they wobble?

Only if I try to roll them without being attached to my rim.

Or is it just nothing but the rims?

My guess is it's nothing but the rims. For now. Your rims need to be trued.

Or is it the forks or what?

Probably not. Yet.

Thanks for your help so far

Once again, your biggest help will be thoroughly reading these two sites:
http://www.sheldonbrown.com/
http://www.parktool.com/repair/

 

[hedoe]

I simply can't do this...........

I mean, earlier you wrote about powder coating the (Wal-Mart) frame, and adding an XTR crankset and derailleurs. That's like applying 12 coats of PPG to a 1984 Yugo, and then slapping in a Ferrari transmission. You might be able to do it, but why would you?


They aren't straight at all. In fact, they're round.


Only if I try to roll them without being attached to my rim.


My guess is it's nothing but the rims. For now. Your rims need to be trued.


Probably not. Yet.

Once again, your biggest help will be thoroughly reading these two sites:
http://www.sheldonbrown.com/
http://www.parktool.com/repair/

what a comodian
okay ill have alot of reading to do
the next part
now then moving on

Part 3: Disk Brakes
I want to know everything about them
can they go on any bike?
Does the frame cause any problems?
How much better are they?
Right now I have some cantilever brakes that I tweaked last night
so that they work as well as I want them to
how much better are disk brakes in a direct comparison to the cantilever?
How difficult would it be to put them onto any bike that you grab off the shelf?
can someone tell me what rim to use
here are some specs that i would prefer
black, and 26"

 

[j.r.hawkins]

That would be the cheapo wheels. There’s a saying: “Cheap. Light. Strong. Choose any two.”

My experience might help you appreciate why.

I have two wheelsets for my bike. One came with it that I now only use off-road, and one I bought later that I use exclusively with road slicks. I use the better wheels on the road because that is where the vast majority of my riding hours are spent, commuting. They’ve now done about equal mileage.

The cheaper WTB SX24 OEM wheels were/are very prone to getting out of true, even though I use them with big fat tyres on low pressure. I was constantly tweaking them with a spoke key to try to keep them straight although I’ve now given up. The bearings in the Quando hubs feel crunchy even after servicing. I’ve broken a couple of spokes on the rear wheel just from road use. I’ve since seen comment that WTB wheels have a reputation for being ‘soft’.

The better Alex TD17s are eyeleted, have much better quality hubs, and are still dead true front and rear despite being run off kerbs and used with skinny high pressure Conti tyres on very rough pavement at speed (>70km/h). I’ve never gone near them with a spoke key. The Felt front and Shimano rear hub bearings still feel smooth. Alex has a reputation for being OK, depending on the model but, even so, are usually only found as entry-to-mid-level OEM equipment rather than being desirable upgrade wheels. Other brands such as Sun, Mavic, and top-end Shimano deservedly take that place.

Like I said, you do get what you pay for.

Truing wheels is covered in the book I recommended.

 

[j.r.hawkins]

Part 3: Disk BrakeS

Properly set up cantilevers can be just as effective as discs. On the plus side they are lighter, and for this reason they are still used at elite level in XC racing. On the minus side they wear out the rims, especially in wet conditions, heat buildup can pop tyres if you hold them on during long descents, and if you crash and potato-chip your rim they are worse than useless.

Discs are heavier, but you’ll have zero issues with heat buildup hurting your tyres, they are much more tolerant of wet conditions and are unaffected by out-of-true rims. I like their smoothness, and good name-brand hydro brakes are a joy to use. However, they are more technical to set up and maintain, and if you touch the pads with greasy fingers or chain lube you need to replace them.

You will need to have a frame and fork with compatible mounts and wheel hubs with disc mounting lugs.

I agree that all-black rims without that awful-looking brake track look much better, and when I see disc-equipped bikes that still have that brake track rims it just screams eBay or department store el-cheapo junker.

I want to know everything about them

PLEASE GO BUY THE BOOK.

 

[dabac]

..I only have 18 gears instead of 21
which means that I got shorted

You didn't have 21 gears to begin with. You should never run your chain from biggest front to biggest rear, or smallest front to smallest rear. It's called cross-chaining and won't do your any good in terms of performance or durability. The full rear range should only be used from the middle front. On top of that odds are that some of of the front/rear combos will result in virtually the same gear ratio, further reducing the number of useable gears available to you.