creaking!
I've just replaced my square taper bottom bracket, truvativ and shimano UN55. It creaks when I'm sitting and standing. I've stripped it down several times to no avail.
I've put anti seize paste on the bb threads, axle ends and crank Bolts. How tight do the bottom bracket cups have to be?
I've checked my pedals, taken them off and refitted them with anti seize paste.
I've tightened the seat post, saddle bolts.
It's driving me nuts! Any suggestions more than welcome.
I doubt it'll be the BB cups, but make sure the crank bolts are done up properly tight - I go for as much pressure as I can with a 5" allen key.
Have you tried it with a different set of pedals?
Hadn't thought of that. Will give it a go.
Or rear axle creaking in the frame?
How would you go about resolving that?
Sorry to be the harbinger of doom but I have often found the incurable creaking from frames to be a crack somewhere....had it many times(often with Cannondales). The frame can look in perfect condition but tiny hairline cracks or even internal cracks can creak like buggery. On the other hand it could just be a component not yet checked??
used to have a really annoying creak on my Trek EX8,which turned out to be where the Gore gear cables went into the front cable guide just behind the headtube.
Also had a creak recently from saddle on top of Joplin seatpost, saddles can be repeat offenders for creaks.
what bike is it?
a custom Ti from XACD.
How tight do the bottom bracket cups have to be?Really tight. 60Nm through a 15mm wrench is proppa tight
If it's any help the creaking may be between the cups and the BB cartridge itself. A little grease on the inside of the cups where they touch the body of the BB often fixes it.
rocketman
Thats what I was going to try next.
I've also noticed if I do them up really tight there is a reduction in movement ie they don't spin as freely. Is this normal?
Loose rear derailieur hanger when i had a creek took me months to work it out.
Square taper are terrible for coming loose, and when they do the crank arms are quickly damaged. And when they are damaged, they become worse for coming loose, and they like to creak, a lot: because no matter how tight that nut is, the arm will never sit tight on the spindle.
Could it be that?
The cups are tapered on the inside so that they centre the BB in the shell and I guess if they go too far into the BB shell they could squash the cartridge slightly and restrict the axle from turning but the normal tightening torque and the design of the cups should prevent this.
A smear of grease on the inside of the cups is usually enough without having to overtighten the cups.
Do you have artifical hip or knee joints?
Do not tighten stuff without a torque wrench !
Undo suspects, clean the thread very well and lightly grease before putting it back and torquing to the right amount.
If you over tighten stuff it streaches the bolts and can result in a snapped off bolt, or striped thread. They you will be in a whole world of hell, much worse than a squeak.
Also, simple bits of grit in the thread are enough to cause a squeak.
Does the sound only manifest itself when riding over this bridge...
If so its the bridge. Its notorious for creaking.
I had a terrible creak on my bike, turned out to be the rear dropouts. Gave them a grease and changed the skewer and not hear a peep since.
Saddle rails? My charge spoon creaks like buggery unless I lube the rails regularly
If none of the previos suggestions work, then maybe try a layer of tin foil on the tapers, with plenty of grease between the foil, axle and cranks, all tightened up nice and tight. Thick foil like yoghurt tops is good.
Might not last forever though...
No one has suggested chainring bolts?
I have tightened chainring bolts but not stripped and rebuilt.
I have tightened chainring bolts but not stripped and rebuilt.
Strip and rebuild them then.
Next port of call would be the lower headset race. When you're hauling on the bars that can twist and the noise then travels down the downtube and sounds like it's coming from the BB area. I speak from experience...
Clean and regrease the QR skewer and clean the dropouts assuming you have a QR. Alternatively drop in the skewer from another bike to rule it in/out. Orange 5's are notorious for this.
As it's a titanium frame have a very good look for cracks. I chased a creek on my road bike for months and found nothing, until I found cracks along the non dive side chainstay.
Hopefully it's something else!
Titantium frames seem to squeak more than other materials. I'm always sorting out creaks, drives me mad!!! I'd strip, clean and grease the seatpost, seatpost clamp and seat as thats where most of mine seem to come from.
Ti frame - check for hairline cracks.
Square taper bb's need progressive tightening to a specific torque as you ride. The advice above suggesting monster force is questionable. Assemble with dry tapers and cranks too, otherwise the cranks may go too far up the taper.
I've had a similar issue that I thought was the b/b and it turned out to be the rear hub.... good luck!
Previous issues for me (after trying the usual suspects) have been pedal bearings and headset/stem. Stem's a bit easier to identify as not being near your feet, though.
And on one occasion, the ferrule from the front der. cable tinking on the crank arm.
Saddle was one for me! Couldn't locate it for ages until my mate riding next to me point it out. Always thought it was the BB.
Square taper bb's need progressive tightening to a specific torque as you ride. The advice above suggesting monster force is questionable. Assemble with dry tapers and cranks too, otherwise the cranks may go too far up the taper.
Oh I do love cycling mythology.
Cranks go too far up the taper because of progressive tightening. Cyclists are the only people who assemble taper joints like this dry - where these are used in industry and other engineering applications, the surfaces are always lubricated. If you don't lubricate, then a substantial proportion of the installation force works against friction, which is variable enough that the installation position isn't predictable. The installation force should be resisted by the mechanical forces due to the taper, which results in a predictable installation position for a given torque. Of course nobody recommending dry tapers ever recommends degreasing properly, which is the only way you'd ensure a properly dry joint - otherwise you just have an unpredictable amount of lubrication.
I agree that 60Nm is a bit high. I install cranks by greasing the tapers and tightening the bolts once to 35Nm (remember to also grease the bolt threads and head). I don't know if you'd describe 35Nm as monster torque - it's certainly higher than you can achieve with a normal AK. It's people not using high enough torque on the bolts which leads to the idea that you need to progressively tighten...
As aracer says.
Always lube tapers, tightening once is the right theing to do
The admonition not to grease the spindle finds life mainly in the bicycle trade. When I discussed the "dry assembly" rule with crank manufacturers, I discovered that they had warranty claims from customers who split cranks. However, cranks cannot be split by overtightening them. This can be proven by attemting to do so. An M8x1 bolt is not strong enough to split a major brand crank.Failure from "over-tightening" is caused by repeated re-tightening of properly installed cranks. In use, an aluminum crank squirms on its taper and, because the retaining bolt prevents it from moving off the taper, it elbows itself away from the bolt and up the taper ever so slightly. The resulting loss of preload, after hard riding, can be detected by how easily the bolt can be turned.
I have removed and re-greased the bottom brackets numerous times. I have cleaned all threads in and around the bottom bracket with a wire brush. Finally whilst out riding I asked who was riding someone where they thought the creak was coming from. They said the rear wheel. I've had the cassette off and it looks like the culprit. The pins that hold the cassette together have come loose on the bigger cogs. The creaking only happens in the bigger cogs!
Fingers crossed!
I finally solved this creak!
it was the rear wheel bearing.
Yesterday was the first time in 6 months I really enjoyed a ride. Not having to listen to the annoying creak made me very happy!
Nice one - feels good to banish a creak.
Someone should write out a flowchart to tackle creaks.
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