Bottom Bracket and Crank replacement help
 

Hey guys,

Im new to this biking forum but Ive been on many forums before so I used to search button a few times trying to find answers to my question. I also learned a lot of other information that I did not know about.

One of the things I learned is that my murray road bike is a (pos)? I did not know that when I bought it as a complete for 40 dollars. Im kinda bummed now since I fee like I was ripped off. Oh well. Lesson learned!

My intentions of getting the murray road bike was to convert it to a fix-gear. I got some new wheels and a 17t fixed cog with lockring. I got everything installed on the bike and then realized something was odd about the crank.

My crank is a 1pc crank with 2 sets of gears. I dont mind that it has 2 gears but I realized that my crank has this weird play when I try to slow down. I try to apply pressure to slow down and it seems like the crank moves a tad back before I feel the tension in my legs. I tried to replicate it many times and I was successful. I noticed the chain does not move forward or backward like the crank pedals do. I was told to try and tighten the bolt on the outside of the crank, but that didnt do anything.

Do you guys have any suggestions?

I was also looking to replacing my 1pc crank with a 3pc. I read that I might be needing a conversion kit that has fittings for a modern day bottom bracket. Can you guys point me in the right direction to learn about this?

Thanks!

lol

Depending on where you live...

http://www.bikesnotbombs.org/
http://workingbikes.org/donate
-there are plenty of others

Don't spend another nickel on it.

aw cmon guys. thats not nice. I know its not worth anything, but I really like the bike.

I didnt ask for help finding places to dispose of my bike. :(


Any answers to my questions out there?

You expect a direct answer to your question? OIC, you are a newbie. :rolleyes:

hahah true. But still, cmon guysss.

I know someone has ran into this problem before! Help a noob out!

Any rideable bike is worth $40. You didn't get ripped off, since you can put it back together and should be able to sell it to someone else for $40.


Suggestions:

1. Sell that bike and go to bikesdirect.com and buy a non-POS fixie for $300-350 and actually get to enjoy riding a fixed gear instead of spending time on a kludged together conversion.

2. Be stubborn and insist on polishing a turd, despite the fact that at the end of the day a polished turd is still a turd. Just because it's yours and you really like it doesn't mean it's worth spending more money on, or that you won't hate it when you've spent enough on parts to buy a new complete bike and it still isn't right.

If you're going for option 2, here's what you're going to need to do:

Take a link out of the chain or move the wheel back in the drops. That crank motion sounds like your chain isn't tight enough.

If it is the bottom bracket, you have two options, either

Go to your local bike co-op and disassemble, regrease, rebuild the 1 piece bottom bracket, replacing the the bearings as necessary.

or do the following 3 things.

A. Buy a 1 piece to 3 piece bottom bracket converter ($21.95 - http://www.sheldonbrown.com/harris/opc.html)
B. Buy a new 3 piece crankset. (Pake makes a nice one for about $60.)
C. Buy a new bottom bracket, and make sure to get the right length spindle for it. ($25, and if you buy the Pake crank, you'll need a 107-110mm spindle)
(Yes, this means spending 2.5x as much on a crankset as you did on the bike, which is why bikesdirect.com is so enticing.)

Whatever you do, make sure the chainline is straight within 1-2mm. If it's visibly not straight, and you're riding it fixed, you're looking at a chain falling off or a chainring snapping, both of which get very messy very fast. Add spacers, etc. to make sure it's straight.

Keep the brakes on and make sure they work with new wheels. Tektro R556 are long reach brakes if your existing brakes don't reach. This isn't a bike it's OK to ride brakeless.

You're welcome.

Pay no attention to the buffoons who pick on newbies. Real mature, boys.

What you have is an Ashtabula bottom-bracket. Isn't that a great name? ASHTABULA, Fun! Anywho - your questions will be answered by Sheldon Brown himself.

http://www.sheldonbrown.com/opc.html

Bottom Line: There's hope! If you decide it's truly worth it.

Oh boys.....

http://i424.photobucket.com/albums/p...g/dudelame.jpg

I guess I was dumb enough to rationalize with myself that I didnt need an expensive bike frame since Im not planning to get "hardcore" with it.

I just settled for a frame in good condition and rode nice without prior research about brands and build qualities. I guess the murray was a department store road bike with poor build quality? Is there anything else really that bad with murray frames?

Im only planning to ride this bike during time off from school and during free time. Im not planning to use it every single day to school or anything, I have a car for that.

I got some weinmann deep V style wheels since they look nice. Im dumb for wayover spending on this bike. UGH.

I feel like I might as well jsut continue. As bigvegan put it, im going to polish this turd. Atleast I know itll be my turd with my style.

I checked the chain. The chain is really straight and alined from the cog to the chainring. Its not varying much more than 1mm. The chain is tight, I did the walking method but I guess my bike has a vertical dropout. Its tight, nonetheless.

Im going to see if I can tweek the bb/crank before I resort to changing everything out.

thanks everyone for the help! Ill be back to ask more about what I can do!

bump?