why are square taper B/B 's such a pain in the a£$E !!!

[danpiero]

i am forever losing my patience trying to remove square taper B/B's and removing cranks from them . either you end up with the threads going on the cranks when the extractor tool pulls through and you can't get them off or the B/B cups get seized . once the threads have gone on the crank how is the best way to get them off ? its so frustrating , i used to have this same problem BITD and begin to wonder if i'm cursed ! if there is a modern design that is better than anything retro it has to be the Hollowtech 2 ,it is so simple and you never get this problem !

 

[lewis1641]

i hate to say it but i agree, the hollowtech 2 system is awesome. not a new idea though, my bmx mate tells me profile were doing a similar thing in the 80's with solid axles though

 

[elite504]

never really had a problem with square tapers in near 20 years. . .
And that numerous machines, regular fettling running repairs from home and 10 years in a shop.
Dedent dura-ace extractor with a rotating bush in the centre helps. Cheapies I wouldn't reccomend, esp on your marvelled onza HO cransk or suchlike!

And for the badly damaged stripped repair that comes in, a car ball joint splitter can be used, or on loose BB's, just remove the other arm and BB cup and punch the axle through.

 

[The Ken]

Bullseye cranks (late 70's - early 90's) are the same design as hollowtech (including the hollow axle, only the bearings were more internal and needed a lot of maintenance. I think they were designed for BMX initially but road/MTB versions were made.

I think hollowtech only came out once Bullseye went bust as they had a few patents on the design.

http://www.bikepro.com/products/cranks/bullseye.html

timeline
http://www.mombat.org/Bullseye.htm

nice pics of mark 1 and 2
http://bmxmuseum.com/forums/viewtopic.php?id=18524
From that page: Bullseye Crank ad from BMX Plus, August 86

I still use my bullseyes with hollowtech bearings and shims made by Gil on here, it is how I found the site!

 

[a.davis12]

i too hate square taper bbs. the one on my p7 seized onto the crank and noa mount of anything would shift it. thankfully i had been regularly been wd-40ing the bb and i was able to remove the shell from the frame with the arm still attached. (using c-clip pliers).

 

[drystonepaul]

I'm another one who hasn't ever had any problems (yet) with square taper cranks. But then again I've also got a Dura-Ace crank extractor purchased in about 1992 and used regularly since. You can't argue with quality...
I'm not that keen on working on Hollowtech 2's, but my personal favourite has to be Octalink for ease of use.

 

[danpiero]

i to have got a dura ace tool which ive had forever maybe it is just getting a bit worn now which is why i have these problems . with the cranks the threads only have to slightly strip the once and they are screwed , just like the pointless aluminium bolts that you couldn't tighten much and would round off in no time .

 

[danpiero]

i to have got a dura ace tool which ive had forever maybe it is just getting a bit worn now which is why i have these problems . with the cranks the threads only have to slightly strip the once and they are screwed , just like the pointless aluminium bolts that you couldn't tighten much and would round off in no time .

 

[mtbfix]

Square taper may have its limitations in terms of axle/taper damage but at least it is designed to go in the BB shell in which it finds itself. HT2 exists purely because it is too much hassle for frame manufacturers to up-size the BB shells. Hopefully the next 5 years will see us settle into a BB30/90 standard so proper big bearings can be fitted inside proper big BB shells. Then we can have stiff axles running on bearings housed within the frame, as it should be.

 

[cce]

parks tool is excellent. never had an issue.