Shimano BB-UN25 Bottom Bracket

3/5 (4 Reviews)

Product Description

  • Sealed cartridge assembly

Review Options:  Sorted by Latest Review | Sort by Best Rating

Reviews 1 - 4 (4 Reviews Total)

User Reviews

Overall Rating:5
Value Rating:5
Submitted by LES a Cross Country Rider from North Carolina

Date Reviewed: October 26, 2008

Strengths:    Durable at a great price.

Weaknesses:    None so far.

Bottom Line:   
I purchased this bike used in almost new condition. I typically ride 100-150 miles a week. I've ridden it centuries including a few in the mountains and numerous metric centuries without any problems. I weigh 150 lbs so I don't crush the pedals but I'm in the first third of the pack. I was cleaning the bike today after a wet metric century. Removed the BB and its in great shape, ready to go. With almost 10,000 miles on it in two years I have to give it a 5.

Expand full review >>

Duration Product Used:   2 Years

Purchased At:   Came on the bike

Bike Setup:   Cannondale CADD4 R400 Triple

Overall Rating:1
Value Rating:2
Submitted by UncivilFire a Cross Country Rider from Sherbrooke, Qc, Canada

Date Reviewed: August 12, 2008

Strengths:    Cheap

Bottom Line:   
I had this UN-25 when I bought my Minelli bike. The bike is made for cross-country and is a mid-class bike (about 400$).
After only 3 weeks, my right pedal was making noises. I went to the retailer and he adjusted it. 2 days later, my pedal felt off and I had to walk home.

The retailer explained me the problem was the pedal and he changed it for free. For many reasons, I had no opportunites after that to use my bike for 8 months.

Last month, I got it out and guess what. 2 weeks later, the same noise. I only used my bike in cities and did no jumping but still, this bottom bracket was killing every single right pedal I could buy.

It's cheap, it has a plastic adapter that breaks itself, the metal, the bearings, it's all cheap. I just bought a Truvativ BB Power Spline bottom bracket for 20$ and it's 100 times better than this UN-25. My friend had the same for more than 1 year and he never had any problems. Plus, the adapter is NOT in plastic!

I would recommend this bottom bracket only to people that seats all the time, that don't go faster than 10 km/h (6 mph) and that never EVER jump higher than 2 cm (3/4 in).

Expand full review >>

Duration Product Used:   1 Year

Purchased At:   Came with bike

Overall Rating:2
Value Rating:2
Submitted by A30N a Weekend Warrior from Los Angeles, CA

Date Reviewed: July 12, 2008

Strengths:    In stock at LBS

Weaknesses:    Low torque capacity

Bottom Line:   
I hate the hassle and long wait when it comes to warranty claims, so when the stock el-cheapo BB popped 6 months after I bought the bike, I walked over to my LBS and bought the best BB for the cash I had on hand, which was $50. Funny thing is, the el-cheapo BB that broke came with a metal support cup; the Shimano I had just bought came with a plastic support cup. The Shimano barely made it 3 months under exactly the same riding conditions before making the PSOD (Popping Sound OF Doom). I replaced it with an $80 Campagnolo Centaur which is now the only surviving part on my bike (hit by a drunk driver).

Expand full review >>

Favorite Trail:   Leo Carrillo

Duration Product Used:   6 months

Price Paid:    $50.00

Similar Products Used:   FSA, Truvativ

Bike Setup:   2007 Redline Monocog, FSA 44t chainring, Shimano Nexus Inter-8, 19t freewheel

Overall Rating:4
Value Rating:5
Submitted by Daniel Haden a Weekend Warrior from Houston, TX

Date Reviewed: May 12, 2006

Strengths:    It performs exactly like the UN52, UN53, UN73, and you can't tell a difference.

Weaknesses:    Square taper may "rock" just a bit when standing on the pedals, causing a "rub rub" sensation that is felt, not heard. This is chain drag. This is true of any square taper BB.

Bottom Line:   
If you spend a lot of time standing up on the pedals, and not on the seat, then don't choose square taper.

If you ride normally or occaisionally stand up for hills and little else, then this bottom bracket will be fantastic.

Square tapers are touring class bottom brackets, and, for this, they really go the distance. For distance and for road is the home of square taper.

The tiny bearings make for zero bb friction during most of your ride. That's a nice feature for people that like an easy spin for uphills or into a headwind.

But, if you're a dedicated, power-lifting, out-of-the-seat, pedal masher, who is strong enough to flex your cranks, then avoid square taper technology alltogether.

Expand full review >>

Favorite Trail:   Houston, TX

Duration Product Used:   1 Year

Price Paid:    $25.00

Purchased At:   Southwest Schwinn

Similar Products Used:   UN53 and similar

Bike Setup:   Have used it on road bikes, MTB, and just recently had one installed on my crusier. It is tight, friction-free and fantastic.

Reviews 1 - 4 (4 Reviews Total)

Review Options:  Sorted by Latest Review | Sort by Best Rating