Square taper, grease or not!!!!
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We_are_Stevo
Old School Grand Master
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...alternatively, a compelling argument for external BB's 
Well,im decided
Too much evidence coming from people in the engineering and bicycle industry even quoting University textbooks. The no crowd dont appear to know and havent really put forward any constructive instead relying on evidence of different taper interfaces which in no way can be compared.
You've lost guys ,give it up
Doesnt matter how long youve been riding,you can still be doing things wrong.Its down to ignorance.
Too much evidence coming from people in the engineering and bicycle industry even quoting University textbooks. The no crowd dont appear to know and havent really put forward any constructive instead relying on evidence of different taper interfaces which in no way can be compared.
You've lost guys ,give it up
Doesnt matter how long youve been riding,you can still be doing things wrong.Its down to ignorance.
dyna-ti":279xcg09 said:Well,im decided
Too much evidence coming from people in the engineering and bicycle industry even quoting University textbooks. The no crowd dont appear to know and havent really put forward any constructive instead relying on evidence of different taper interfaces which in no way can be compared.
You've lost guys ,give it up
Doesnt matter how long youve been riding,you can still be doing things wrong.Its down to ignorance.
According to Campagnolo, you're in the ignorant group :twisted: not quite such a lost cause!!!
I think it's safe to say that the lack of square taper fitment in any other aspect of any known industry, tells you that a) it's daft, and b) splined FTW.
retrobate":279xcg09 said:Do what the manufacture recommends!
eg. Campagnolo recommend a dry taper interface and a dry bolt thread. Raceface recommend lubrication.
I can see the point of both arguments.
Grease (anti sieze compound, a specific loctite type compound or JC4) to reduce the chance of corrosion between different metals (very good point and one that I go by on non tapered interfaces).
But my interpretation of engineering practices is that (as a generalisation) a square taper (with no manufacture information) is nothing like a splined or keyed shaft and should not be greased as this could lead to the crank moving too far up the taper thus increasing the stress on the corners of the female square taper leading to possible cracking in the future.
Even if you installed the campy cranks on a dry taper but greased the bolt and then used a calibrated torque wrench at the correct setting you will still have over torqued the bolt (because of the grease reducing the friction) and put more stress on the taper than the designers intended. Again do what the manufacture recommends!
Conversely if you installed the raceface cranks dry with a with a torque wrench the crank will not be seated on the taper far enough with the risk of play developing.
To all the other aircraft engineers. Would you grease a componant when installing it if the AMM said it should be installed dry? And I have to admit that I dont recall any square tapers on any of the aircraft that I have worked on so I have no specialist knowledge regarding square tapers on aircraft.
Personally I dont grease
Looks like we can get 10 or better out of this after all! A fresh round of assertions, insults, and inuendo have just been launched.
And one point of correction to an assertion made by the Yes side a couple of posts up (...lack of ST fitment fitment in any other aspect of any known industry...). ST fitment is pretty commonly used on the control knobs of gas stoves etc. and some brands of plumbing fixtures/faucets (at least on this side of the pondl).
A question for the factions? Why put a lubricant on an interface that you want to be immobile? If AS compound inhibits corrosion AND inhibits movement, why use a "grease"? Stevo, FC, and LGF (seawater notwithstanding), care to weigh in on this?
And one point of correction to an assertion made by the Yes side a couple of posts up (...lack of ST fitment fitment in any other aspect of any known industry...). ST fitment is pretty commonly used on the control knobs of gas stoves etc. and some brands of plumbing fixtures/faucets (at least on this side of the pondl).
A question for the factions? Why put a lubricant on an interface that you want to be immobile? If AS compound inhibits corrosion AND inhibits movement, why use a "grease"? Stevo, FC, and LGF (seawater notwithstanding), care to weigh in on this?
It's many years ago I've used a Campagnolo square taper on a road bike. Let's face another fact - they are engineered for a rather clean environment with major influence from the warm and sunny south Europe. The hubs, pedals, BBs and headsets BITD were awful with absolutely no kind of weather proofing at all. Is it any surprise that they went out of the MTB market?
Now I'm not saying they don't know what they are doing, but putting a small amount of lube on the Campagnolo cranks I had BITD did not cause any problems. Even with the very naff 7mm allen bolt they used for there self extracting bolts (as apposed to the Shimano 8mm bog standard bolt).
I have just checked some NOS Shimano UN72 I have, and guess what...there is an hotchpotch dab of white grease like stuff on the tapers......I assume there is a reason for that....or.....?????
I actually strongly disagree the square taper "clearance interface" is crap. This thread demonstrates (someone mentioned finding a bike that had been in a pond!) it can work and be reliable even without following basic engineering practices and with no maintenance at all. I would like to see some of these more modern interfaces that could handle similar situations over the long-term just for the sake of discussion; so far I've used a Hollowwhatever V2 once which came loose on the NDS and removed another from a bike that had virtually no use where the connecting tube was covered in rust along with the various spacers. That to me was pretty crap.
Regarding the question, I'm of the belief what Jobst Brant says "Lubricating the spindle for assembly assures a predictable press fit for a given torque. Without lubrication the press is unknown and galling (aluminum transfer to the steel spindle) may occur during assembly." - in my basic engineering world and why I do it is that the lube only serves to momentarily reduce friction during assembly only; the result being a crank that sits well on the axle and doesn't fall off.
We are on 10 pages now...can't believe I'm doing this but it is snowy outside....do I go up a notch on the Retrobike pecking order
Now I'm not saying they don't know what they are doing, but putting a small amount of lube on the Campagnolo cranks I had BITD did not cause any problems. Even with the very naff 7mm allen bolt they used for there self extracting bolts (as apposed to the Shimano 8mm bog standard bolt).
I have just checked some NOS Shimano UN72 I have, and guess what...there is an hotchpotch dab of white grease like stuff on the tapers......I assume there is a reason for that....or.....?????
I actually strongly disagree the square taper "clearance interface" is crap. This thread demonstrates (someone mentioned finding a bike that had been in a pond!) it can work and be reliable even without following basic engineering practices and with no maintenance at all. I would like to see some of these more modern interfaces that could handle similar situations over the long-term just for the sake of discussion; so far I've used a Hollowwhatever V2 once which came loose on the NDS and removed another from a bike that had virtually no use where the connecting tube was covered in rust along with the various spacers. That to me was pretty crap.
Regarding the question, I'm of the belief what Jobst Brant says "Lubricating the spindle for assembly assures a predictable press fit for a given torque. Without lubrication the press is unknown and galling (aluminum transfer to the steel spindle) may occur during assembly." - in my basic engineering world and why I do it is that the lube only serves to momentarily reduce friction during assembly only; the result being a crank that sits well on the axle and doesn't fall off.
We are on 10 pages now...can't believe I'm doing this but it is snowy outside....do I go up a notch on the Retrobike pecking order
I did finish the measurements (ran out of spare crank bolts partway into the non-DS sequence though). Results show a high positive correlation to the use of grease and the amount of suck-on distance. An interesting and unexpected metric emerged though. In the greased fitment grouping, the amount of suck-on was more a factor of grease being used on the crank bolt threads than on the taper surfaces.
The difference in the amount of suck-on between DS and non-DS is due to the difference in dimenions of the spindle taper itself, DS versus non-DS. To make sure that my spare BBs weren't an anomoly I went to the LBS last night after work, dial caliper in hand. The guys at my LBS were a bit puzzled with me, as I was asking to look at their drawer full of Shimano ST BBs. I had to agree only to measure those whose boxes were alredy open before they'd let me proceed.
I'm gonna stick to As'ing the taper and crank bolt threads. Oh, we hit 10 pages...
The difference in the amount of suck-on between DS and non-DS is due to the difference in dimenions of the spindle taper itself, DS versus non-DS. To make sure that my spare BBs weren't an anomoly I went to the LBS last night after work, dial caliper in hand. The guys at my LBS were a bit puzzled with me, as I was asking to look at their drawer full of Shimano ST BBs. I had to agree only to measure those whose boxes were alredy open before they'd let me proceed.
I'm gonna stick to As'ing the taper and crank bolt threads. Oh, we hit 10 pages...
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gdb2b":2r3dwh7t said:
It should be noted not all greases are equal, grease like copaslip has copper parts as do other pressure greases like 'EP' types but they may have other thing added to do a similar job, I believe these are what should probably used. As far as I know Lithium based greasers should not be used, they're not particularly waterproof and as mention quite often go dry.
Grease would be used as when it is under pressure and the shear force exerted it should thin to an oil state to give a nice smooth action to fitting on the taper, then thicken up to carry out it waterproofing and any additives to bind to the surfaces preventing both surfaces touching.
Though, something to be research if anyone cares that that is what happens or if there is somebody in the grease industry ?
We_are_Stevo
Old School Grand Master
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It's actually quite ironic my being a staunch 'Yes' man because white lithium based grease is the bane of my life at work...
...I'm forever banging on about people not using it because the damn stuff attracts all the dirt and shite then sets like glue when the cold weather arrives :x
The mantra our tutors drummed into us was, unless packing out a bearing, 'Wipe it on, wipe it off' and what's left is all the lubrication you need.
I don't get all this movement rhetoric from the 'No' camp; where is it going to move to, and how! Half a mil 'suck on' damaging? Come on... :facepalm:
...I'm forever banging on about people not using it because the damn stuff attracts all the dirt and shite then sets like glue when the cold weather arrives :x
The mantra our tutors drummed into us was, unless packing out a bearing, 'Wipe it on, wipe it off' and what's left is all the lubrication you need.
I don't get all this movement rhetoric from the 'No' camp; where is it going to move to, and how! Half a mil 'suck on' damaging? Come on... :facepalm:
Manufacturer update.
Picked up some NOS Topline cranks at the Bristol Bike Jumble on saturday. Here is the fitting info.
Apply a light coating of grease to the spindle taper before installing Crank Set. A lithium base or water proof grease is suitable.
Torque Crank Set retaining bolts to (30 ft/lbs.) before your first extended ride. Retorque after 80 km (50 miles) and check every 300 km (190 miles)
Campy no grease.
Raceface and Topline grease.
Anybody got any other manufacturers fitting data?
Picked up some NOS Topline cranks at the Bristol Bike Jumble on saturday. Here is the fitting info.
Apply a light coating of grease to the spindle taper before installing Crank Set. A lithium base or water proof grease is suitable.
Torque Crank Set retaining bolts to (30 ft/lbs.) before your first extended ride. Retorque after 80 km (50 miles) and check every 300 km (190 miles)
Campy no grease.
Raceface and Topline grease.
Anybody got any other manufacturers fitting data?
