hi just ruined a great Middleburn RS7 drive arm the square taper is totally rounded off and its pretty much unusable now . Think it was a case of using the bolt that came with the BB ie not great that had a habit of working itself lose every couple weeks or so . Any ideas on what crank bolts to get and methods to stop it working itself lose all the time . Cheers
Square Taper Round Off Prevention
- Thread starter deepsubz
- Start date
Make certain the fitting holes on the arms as well as the BB axle flats are clean and dry. Use some copper anti-sieze on the fitting bolt threads and then tighten it as tight as you can(not gorilla tight) just human tight. I've been wrenching cycles since the dawn of time(60's) and never seen one that was properly fitted come loose.
Cheers
Cheers
- Feedback
- View
gtRTSdh":4hwq6rlf said:
I don't beleive the difference. My old Deore DX cranks feel just as stiff as my XT HT2 modern cranks. And I am a chunky fellow who likes a good sprint. ;-)
With square taper I take a Park 14mm crank bolt spanner out in my pack and tighten the cranks at the lunch stop or any long stops. After a couple of rides they have bedded in and no problems.
Keeping the interface between BB and crank dry during installation is key, and coppaslip on the bolt threads as already stated.
Rob Atkin":1f64ibhi said:
Fair enough, but what I can say that I've never thrown a splined crank away due to the attachment to the BB being fooked! Although if not tight splined systems can be ruined, and octalink V1's aren't as indestructable as V2 and hollowtech external jobs.
My crank destroying friend tells me isis is fairly useless.
- Feedback
- View
deepsubz":1wzsaw15 said:
Don't use grease on the spindles. Some loctite on the bolt perhaps.
I had similar problems with a crankset once (cheap Deore one). I overtightened it a bit, and never had problems with it again.
As for 14mm bolt vs 8mm Allen : there's no real reason to choose one over the other. Both will do their job just fine. I much prefer the Allen though, just because it looks better IMO.
- Feedback
- View
deepsubz":2na20j7j said:
Depends on the crank really.
RaceFace for example are machined to have the taper 'greased'. They pretty much demand you grease them if it is a 'brown' taper or a Ti-Taper as they react more with the Alu of the crank arms. Chrome plated like UN90/71.. do not have the reaction problems apparently.
If you fit them without 'grease' the interface wouldn't be how it was machined for.
I use allen bolts to fit mine on. Never had a problem (touch wood effect Ti)
Similar threads
