HELP - Can not tighten RHS crank arm - Kalkhoff Endeavor ???

[bilabonic]

Hi All

Arm keeps coming loose, I tried a 9/16, 1/2, 13mm, and 14 mm. The 1/2, 13mm are too small to get over the nut, but the 14mm and 9/16 are too big and are in danger of rounding the nut out. I have ZERO clearance to get an adjustable in there, nothing gets a bite.
What do I do?????

Looking here it looks like i need a 1/2 AF or 5/16 UNF BUT it needs to be a socket type as a ring spanner or adjustable etc will not fit !!!!

http://www.sat.dundee.ac.uk/~psc/spanner_jaw.html#Jaw_Size_Table

Anyone help ?

Thanks

 

[Pholcus]

This seems quite odd, crank arm nut is usually 14mm, standard on most bikes, and needs a socket to remove. Are your crank arms square taper or splined?

 

[flecc]

Sometimes a tube or socket spanner needs to be tapped on with a hammer, I've often found this with the Giant Lafree Panasonic unit bikes. It almost seems the nut is swelling very slightly when tight.
.

 

[Nealh]

If its a 14mm socket try a different socket as some work better then others, some have a multi spline internal to grip and others are 6 or 8 sided and will do the job better.

 

[Fordulike]

What type of socket are you using? I found a 14mm of this type felt loose and as if it would round the nut:


Then I tried a flat edge type and it felt a lot snugger and less likely to round off the head:


Edit: Nealh beat me to it lol

 

[Nealh]

Two minds thinking alike .

 

[Deleted member 4366]

You need a hexagon socket , not a bihex. There should be one on your crank puller. Make sure you degrease the square taper spindle and hole in your crank before re-assembling.

 

[bilabonic]

What crank puller ?
I have tried about 8/9 from differing sets, both splined type socket and the hex type out of the sets, from Snap-On to Halfords sets, to loads of other sets that i have had over the years ??

Cheers for replies guys i will have a play tom.

 

[Kuorider]

Replace the crank arm, if it's run loose for some time the taper has probably fretted or stretched a bit and will never tighten properly.

 

[bilabonic]

Thanks for reply guys, a 1/4 WW was to small, when i have removed the nut is looks like it's a Flanged type with 'serrated' end to 'lock' onto the soft metal crank.
This has FULLY worn off, plus with the 'rounding' of the nut i think i need a new one.....

Can anyone confirm the the thread size of the shaft so i can get a new like this for example (nyloc type)-

http://www.ebay.co.uk/itm/M5-M6-M8-M10-M12-FLANGE-NYLOC-INSERT-LOCK-NUTS-HIGH-TENSILE-BZP-ZINC-ABOLT-FTB-/111111992475?pt=LH_DefaultDomain_3&var=&hash=item19deca749b

I will also pull the arm off and grease it as recommended.

Cheers

 

[Deleted member 4366]

Don't grease it. You have to degrease it. That means remove any grease/oil with solvent (petrol).

 

[bilabonic]

My other arm is coming loose ALL the time now !!!!
Sick of the bike !!!!
Used mallet to force arm on and tightened to full extent with NO slip on nut.
STILL works loose when i hit the VERY steep hill at my home, plus the creaking noise in embarrassing.

Wish i had kept myself build Bafang !!!!

Rant Over !!!!

 

[Kuorider]

If you could post your location another member on here may be near you and able to help out. If your cranks are alloy the taper may have stretched and the bolt will bottom out on the spindle end before the crank is tight on. No amount of tightening will fix this. Did you try a new crank? This is really an easy fault to fix, at most a new spindle and cranks will cure the problem. If you are a powerful rider you may be best with steel cranks. Spindles and steel cranks are cheap. Your problem probably started with the cranks becoming slightly loose and in running this way for a while have spoiled the tapers in the alloy. By the time you noticed the creaking the damage was done. As Dave pointed out, the tapers must be totally clean and dry before assembly. Can you post a few pics of the parts for further help.

 

[bilabonic]

Yes, the crank arms are soft alloy and the 'fixing' nuts are self biting, i totally understand what you are saying and the 'bike' can not handle the pressure i exert on the steep hill climb.
I have torqued the nuts to correct spec using Park tool torque wrench.
The spindle is mild steel i presume.
The bike is only 6 months old and for £2500 i expected better !!!
I am confident the arms when pressed onto the shaft are SOLID, the securing nuts with their cutting threads have worn smooth now.
The tapers are SPOTLESS, but they still come loose ??? (used electrical degreaser, i'm a industrial sparky by trade)

Thanks for the reply, i work in engineering have access to virtually everything, the shaft is not a standard 1mm thread, not sure where to go from her guys.

New bolts/self locking washers (star type.not ring so they cut into the arms?)
A think a Nyloc nut would solve it BUT it should not have happened/developed this fault.

Thanks for the replies guys, i am in South Wales SA12 area.

 

[Kuorider]

There is some good info here http://sheldonbrown.com/bbtaper.html this may help to pinpoint the fault. At 6 months old this should really go back to the dealer under warranty as it can only be faulty material or a bad fit from day one. The spindle is hard steel. Your reference to a Bolt then Nyloc nut is a bit puzzling. Does your spindle in fact have a male thread rather than the type shown in the link above. The washers should be thick plain steel ,no need for lock washers which spoil the surface. Kalkoff have a good reputation so your dealer should be on this right away. This is a simple fault and should be repairable

 

[Kuorider]

Just a thought. As you work in engineering ask your mates for some 'engineers blue'. Smear this inside the crank taper then tap it on gently to the spindle, pull off carefully and examine the mark left by the blue on the spindle taper. This should reveal the area of contact and should be even over the whole surface on all four faces. This test may show the problem.

 

[bilabonic]

IT just get's worse !!!!!

Apart from the crank arms (i'm aware of threadlock mate, cheers)

The Chain has now snapped FFS !!!!!!!

Cycling up a medium steepness hill, not in full assist mode, dropped down a gear and FOOKED !!!!!!

I HATE THIS BIKE !!!!

HOPE I CAN RETURN IT TO 50CYCLES !!!!!!

£2500 for piece rubbish !!!!!

ARRGGHHHH !!!!!!!!

 

[tillson]

HOPE I CAN RETURN IT TO 50CYCLES !!!!!!!

Why have you not done so already? If it's only 6 months old it is still under warranty and if there is some sort of manufacturing defect, they will rectify it.

I may be wrong, but from your messages I get the impression that you aren't what used to be called, a Fitter by trade. Someone with a bit of finesse with a spanner and precision components. Mallets, adjustable spanners and AF spanners have no place in the fault that you are trying to fix and you have more than likely damaged something in the process.

Chains do break, usually through wear or lack of maintenance or both. You can't blame this on the bike type.

You need to seek professional help from 50 Cycles.

 

[bilabonic]

I'm an Electrical Engineering not a 'fittter' !!!! Not a 'bodger' and not at all inept at looking after cycles (which i have 5 high end) with ALL the correct tools/torque wrenches etc. I prefer PARKTOOL.

The chain has snapped and not in the place where the link is.

I resolved the arms coming loose with new locking washers and Nyloc fluid.

I have contacted 50cycles and have also noticed the latest model has no chain but is belt driven......why the upgrade ? When a chain/standard gearing system is easy to maintain.

 

[tillson]

I have contacted 50cycles and have also noticed the latest model has no chain but is belt driven......why the upgrade ? When a chain/standard gearing system is easy to maintain.

Im not really familiar with the Endeavour. Is it a 400 Watt motor with derailluer gears?