racerken

Hi,

I'm new to this site and really new to repairing bikes but I have a ton of tools as I'm more of a car expert.


If I'm posting in the wrong section, I apologize.


I have this 2009, Specialized Vita and have 2 basic questions to the forum.


1. Bottom Bracket. the unit I have is a Chin Haur CH 52 (I think, there is a machining scar on top of the 2 digit), 68x122LEN, BC 1.37 x 24T. OK, I know that the width of the frame tube in which this cartridge fits into is 68, the shaft end to end is 122. When I look up this bearing (In Germany) there is no direct hit so I'm wondering what the proper replacement is. The crank on this unit is Shimano FC M-131, and gears are SG 48-38-28 KH2. The Shifters are Shimano Altus (don't know if that makes any difference...) Just out of curiosity, I go to the Shimano website and notice the BB-UN100 and BB-UN101 on eBay which matches via my mark II eye ball and the specs. that said, there are 2 rows of threads instead of one continuous on the outer sleeves. Are there meant to all be interchangeable?


2. Rear Wheel Freehub/Freewheel. I have an 8 speed cassette and the freehub is not consistent and almost skips a click. Instead of the Klick, it's a KuLick. When I google Shimano Freehub, I get a ton of similar looking items. At this one site, the part number Y-4FL98090 seems to fit. What am I supposed to search for?


Sorry if my questions are 'stupid' but I am....


Any assist would be great.


Thanks,


Ken

Charliekeet

Hi Ken,

You're on the right track with those bottom brackets. They're square-taper, which is what your crankset takes, so as long as you get the bb shell width (68mm) and spindle length (122 or very close to it) the same, that'll work.
Re: the hub, they usually say on there somewhere, like 'FH-MT200-B' for example. Shimano has whole pages of things that work together https://bike.shimano.com/en-EU/produ...tus-m2000.html

You may want to have a shop check out your hub, as it might not need replacing.

alcjphil

It isn't a sure thing that you have a Shimano hub despite the fact that your freehub is Shimano compatible. Many bikes have wheels with hubs that were not made by Shimano. You need a freehub that matches your wheel.

racerken

Thanks for the replies.

Updates: I received a Sunrace bracket ordered 'in the blind' with 68x122.... It is a replica of the shin haur, the tube states SunRace but the bearings are Shin Haur! So that was a 10 Euro value buy. Definitely a Shimano look alike but it fit like a champ!

The FreeWheel. I guess using the term hub is incorrect on my part because I don't want to take apart the spokes....

I am looking at this www (dot) rosebikes.de/shimano-freilaufkorper-49965 This looks identical to what I have. I don't know the mating surface details because I'm waiting for my 11 and 12mm hex to arrive.... I hope that's the correct size. I think I'm going to wait until I can remove the freewheel before going forward.

alcjphil

If you have an 8 speed cassette it is about 99% certain that you do not have a freewheel. Freehub is the correct term for the body onto which your cassette mounts

racerken

OK, really dumb question on loosening the Freehub:

It's a 11mm hex. Is it right hand or left hand thread?

It is really stuck and I'm worried that my super human strength might crack the earth...

dedhed

Those are typically counterclockwise to remove.

racerken

Thank you All!

My OCD side gave up on it last night and started re-assembly. New FR/RR bearings, took apart all brakes, re-greased, new bracket, cleaned/greased headset bearings, new pedals, and cleaned (3 steps: brake cleaner, alcohol, alcohol) + Wax pot. It's like new. Parts were about 50 Euros!!! My new hobby is here.


If you have any car questions, especially Porsche/Mercedes/Nissan/Subaru, ping me.

racerken

Oh, chain is stretched to 0.5%.
I'm going down the rabbits hole.

My current chain is a CN-HG71 'Narrow' w/124 links.. weird, there is 116 and 138 from Shimano so I'm assuming the links are adjusted.

Do I have to purchase Shimano or will any other 8-speed chain work with the proper link count? I'm so confused with the comments in Amazon and other bike parts shops 'It's great' vs. 'It won't fit my Shimano'... Confusing.

caloso

Any 8-speed chain will fit. Buy a chain tool if you don't have one already. Buy the chain with more links and remove the extras when you size and join up the new chain.

xlbs

Right hand thread. These are usually tight...so work away at it...

alcjphil

You have to buy a chain with enough links so that you can cut it to the correct length

Lakerat

"It is really stuck and I'm worried that my super human strength might crack the earth..." Lookie there, a mechanic needless of a BFH.

Doug64

Why do you want to remove the freehub?

Camilo

And to OP: buy a chain that has a "quick link" connection rather than having to insert a special pin or push back in a pin. It's a lot easier and fool-proof. Even if you have to buy a 9 speed chain to do that. 9 speed will work fine on an 8 speed set up. Read up on how the connection is made so you don't accidentally shorten the new one too much.

racerken

Because some of the clicking is not as sound (as in the spring loaded cog is not fully settling into the groove) as, say my Cervelo. Anyway, I quit this one because my neighbor wanted her bike back and she didn't seem to notice any issue. I'm just OCD...

The Cervelo, was my first overhaul after owning it for 12 years and that bike has a removable freehub, easy to maintain. Further it was not mud soaked or abused in the weather so everything basically came apart just like the Youtube videos. I learned alot.

racerken

Funny, that's exactly what I did after spending days cleaning and hot waxing it. I removed the external link.... the chain was close to 5% anyway so it was a learning and laughter experience. I also used a pin but forgot to run the chain thru the rear deraileur... Total 'wine' induced mistakes. Still it's fun. Better than Netflix.