DRM
Guru
- Location
- West Yorks
I fitted the First DX 30 to my old Raleigh Max, was a decent item for not a huge cost, Spa deliver quickly too
What will replace the quality of the discontinued Shimano BB-UN55?
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Ajax Bay
Guru
- Location
- East Devon
https://www.cyclechat.net/threads/bottom-bracket-size.269100/#post-6206033
"the UN-55 has been discontinued and its replacement in the Shimano stable is the UN-300:
https://www.tweekscycles.com/uk/shimano-bb-un300-square-tapered-bottom-bracket-2012876/ "
I have bought one - not yet in a shell. The only apparent difference is a rubber(ish) ring on the drive side: function unclear.
"the UN-55 has been discontinued and its replacement in the Shimano stable is the UN-300:
https://www.tweekscycles.com/uk/shimano-bb-un300-square-tapered-bottom-bracket-2012876/ "
I have bought one - not yet in a shell. The only apparent difference is a rubber(ish) ring on the drive side: function unclear.
rualexander
Legendary Member
I've been using a Stronglight jp400 from Spa for several years now.
https://www.spacycles.co.uk/m16b0s110p140/STRONGLIGHT-Bottom-Bracket-JP400-Aluminium
rogerzilla
Legendary Member
On a dry-weather bike, a cup and cone unit lasts more or less indefinitely with occasional servicing. Hopeless in the wet, though, as water always gets past the mediocre sealing, if it doesn't get in via the seat tube instead.
raleighnut
Legendary Member
- Location
- One of the 'Elite'
Yep to a degree although 'plenty' of grease does help mitigate that and not locking the bike away in a cold shed/garage when it's wet helps, suppose I'm lucky having a Conservatory to dry bikes off in is a bonus.
Tom B
Guru
- Location
- Lancashire
I'm not normally a brand snob when it comes to tried and tested stuff. But equally Shimano make some properly sorted stuff at very affordable, sometimes crazy low prices when you think about the manufacturing involved.
This is especially true of the everyday, non revolutionary stuff.
I've used Sunrace BBs in place of UN55 and seen them last under 3000miles. I was of the view sunrace was half decent stuff, so smashed through a few of them before undecided to cough up double for a UN55 on the basis that I might have had a bad one, or from a bad batch. On each occasion the crank side bearing failed turning to a rusty mushy mess. I suspect may of the off brand products such as this drop out of the same factory.
The UN55 is at about 12000 miles seeing daily use in three winters. In the last week it has developed a creak, which I have silenced by dropping some oil in both sides. I dare say it's death is near so have just ordered the un300.
I do wonder what has prompted Shimano to make the change from what was a pretty sorted product. Given you didn't hear people bleating about any sort of flaw, life seemed good. I can only assume that the new straight body is easier (and cheaper) to manufacture. There must have been some motivator for them to go through a design, testing, marketing and delivery process for a new product with all the costs that entails. I suppose in the volume that these BBS are produced and sold savings of 1p per unit adds up.
But in short go for the un300. Yes they're dearer. But far better value.
This is especially true of the everyday, non revolutionary stuff.
I've used Sunrace BBs in place of UN55 and seen them last under 3000miles. I was of the view sunrace was half decent stuff, so smashed through a few of them before undecided to cough up double for a UN55 on the basis that I might have had a bad one, or from a bad batch. On each occasion the crank side bearing failed turning to a rusty mushy mess. I suspect may of the off brand products such as this drop out of the same factory.
The UN55 is at about 12000 miles seeing daily use in three winters. In the last week it has developed a creak, which I have silenced by dropping some oil in both sides. I dare say it's death is near so have just ordered the un300.
I do wonder what has prompted Shimano to make the change from what was a pretty sorted product. Given you didn't hear people bleating about any sort of flaw, life seemed good. I can only assume that the new straight body is easier (and cheaper) to manufacture. There must have been some motivator for them to go through a design, testing, marketing and delivery process for a new product with all the costs that entails. I suppose in the volume that these BBS are produced and sold savings of 1p per unit adds up.
But in short go for the un300. Yes they're dearer. But far better value.
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GuyBoden
Guru
- Location
- Warrington
The body of the new UN300 reminds me of the new inexpensive UN26, also made in Indonesia, they have a different body than the old UN55.
The old UN55 was made in Singapore, but so was the old UN26, I think production of Shimano BBs seems to have been changed to Indonesia.
I've had a UN55 on my summer road bike for over 5 years and there is still no signs of wear, let's hope the new UN300 is as durable and reliable.
The old UN55 was made in Singapore, but so was the old UN26, I think production of Shimano BBs seems to have been changed to Indonesia.
I've had a UN55 on my summer road bike for over 5 years and there is still no signs of wear, let's hope the new UN300 is as durable and reliable.
fossyant
Ride It Like You Stole It!
- Location
- South Manchester
Just fitted the UN-300 to my old MTB - it's slightly different construction in that the non-drive bearing isn't inside the casing - it's flush mounted. The extra rubber ring is an additional seal. At least with this you can service the non-drive bearing. Wether it lasts as well who knows.
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GuyBoden
Guru
- Location
- Warrington
Anyway, I've found a whole thread about the venerable UN55 BB on the other Cycle forum.
https://forum.cyclinguk.org/viewtopic.php?p=1530315#p1530315
https://forum.cyclinguk.org/viewtopic.php?p=1530315#p1530315
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GuyBoden
Guru
- Location
- Warrington
With the end of the BB-UN55, after a bit of research, I've decided to replace all of my square taper BBs, when they wear out, with Tange Seiki LN-7922.
They have good reviews for durability and have a reasonable current price of between £24-£29.
They have good reviews for durability and have a reasonable current price of between £24-£29.
Ajax Bay
Guru
- Location
- East Devon
Why "after a bit of research" (share?) do you judge this Tange BB to be preferred to Shimano's replacement: the UN-300? What data are there on "durability"?
https://www.tredz.co.uk/.Shimano-BB-UN300-Tapered-Bottom-Bracket-British-Thread_232243.htm
I have bought a Stronglight one for my next build (from Spa Cycles
https://www.spacycles.co.uk/m16b0s110p140/STRONGLIGHT-Bottom-Bracket-JP400-Aluminium
https://www.tredz.co.uk/.Shimano-BB-UN300-Tapered-Bottom-Bracket-British-Thread_232243.htm
I have bought a Stronglight one for my next build (from Spa Cycles
https://www.spacycles.co.uk/m16b0s110p140/STRONGLIGHT-Bottom-Bracket-JP400-Aluminium
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- Location
- London
thanks for the reply - seconding ajax's question (polite I think) can you share your research?
I have at least two 110 spindles and two 113 spindles laid up waiting but always nice to have alternatives.
Probably irrelevant but I rate Tange's frames and threaded headsets.
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GuyBoden
Guru
- Location
- Warrington
I've not quite finished my PHD thesis "Bottom Brackets: Replacement for the BB-UN55", it is the most important part of a doctoral research degree: the culmination of three or four years of full-time work. 
The Tange Seiki LN-7922 is my personal choice for quality and price, based on solely reading information on the internet about BBs for a few weeks, nothing truly scientific, but a good choice, based on the info available.
Why did you choose the Stronglight?
SpaCycles seem to be using inexpensive FIRST COMPONENTS Bottom Bracket F-2001P in their own builds.
The Tange Seiki LN-7922 is my personal choice for quality and price, based on solely reading information on the internet about BBs for a few weeks, nothing truly scientific, but a good choice, based on the info available.
Why did you choose the Stronglight?
SpaCycles seem to be using inexpensive FIRST COMPONENTS Bottom Bracket F-2001P in their own builds.
Ajax Bay
Guru
- Location
- East Devon
A UN-300 wasn't available in the right spindle length when I bought a wedge of items from Spa: so I went for Stronglight rather than the cheaper 'unbranded' alternative. The fact that Spa are using the 'First' BB must be a recommendation in itself.
Sorry if my question could seem impolite: was just genuinely interested what you'd found on comparative durability. I did do some net searching but failed to find owt where you succeeded.
Sorry if my question could seem impolite: was just genuinely interested what you'd found on comparative durability. I did do some net searching but failed to find owt where you succeeded.
Juan Kog
permanently grumpy
Tange LN-7922 is my choice too. I have just fitted a 107 mm one to my Surly Steamroller. It replaced a Stronglight JP 400 , which had been fitted just over a year . It was running smoothly with no play , but had developed an irritating ticking/ creaking sound.
The Tange BB appears to a well made component and it’s actually made in Japan, which I see as a mark of quality.
