Author Topic: TORQUEING REAR AXLE  (Read 202 times)

Offline StevieWonder

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TORQUEING REAR AXLE
« on: October 11, 2019, 01:35:55 PM »
Does anyone know, if the rear axle bolt can be torqued up without removing silencers/mufflers #3 and #4?

The 24 mm axle nut has a torque setting of 58 – 72 Ft/Lbs, which in itself calls for significant leverage and more than an open ended spanner.

However, I have found that with the silencers supported and the pillion foot peg/ silencer support withdrawn the additional space around the rear axle nut is still insufficient to fit a socket or a crowfoot spanner/wrench and attach the torque wrench.

As the axle nut must be regularly accessed to make drive chain adjustments, surely there is a technique to set the torque with silencers in place?
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Offline Nurse Julie

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Re: TORQUEING REAR AXLE
« Reply #1 on: October 11, 2019, 01:48:46 PM »
No...silencers need to be removed or do what we do, just use a very long spanner and stand on it till the nut doesn't move any further, that's about 65 ft lb torque 😁
Im a Nurse, trust me, this won't hurt.....much !!!

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Offline Bryanj

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Re: TORQUEING REAR AXLE
« Reply #2 on: October 11, 2019, 02:06:04 PM »
I always used the tool kit flat hex ring with an appropriate, bent, fork tube!

Offline StevieWonder

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Re: TORQUEING REAR AXLE
« Reply #3 on: October 12, 2019, 03:55:49 PM »
Trying to tighten the rear axle nut to the correct torque as based upon the kind advice provided by Nurse Julie and Bryanj – ‘Stand on it’ and ‘use the tool kit flat hex ring’ – I got all technical and calculated the bar length required to produce 65 ft Lbs torque.

Torque (ft Lbs) = Lever length (ft) x force (Lbs)     all calcs assume force at 90 degrees to lever.

65 ft Lbs = Lever length x 1 fat b*****d (182 lbs) stood on it.

Lever Length =      65         .
                    182   

Lever Length = 0.357 of a foot ~ 4.25 inches about the length of the tool kit hex ring, without the extension would produce the 65 ft Lbs of torque required, if I stood on the end of it.

So I stood on the unextended hex ring and ……………………. It loosened the nut!

So to tighten the nut to 65 ft Lbs, if I use a bar lever of 10” (0.834 ft)

Force =        Torque   .
                Lever Length

Force =         65       .
                 0.834

Force = ~ 80 Lbs   or 5 Stone 6 Lb   but I don’t know what that feels like?

So if I use 34” of 22mm copper pipe to extend the tool kit hex ring – I know the bend in the bar reduces the force slightly.

Force =                65     .               =  ~ 23 ft Lbs     I know what that feels like.
                   2.834 ft (34”)

So tightened axle nut, but now the hole for the split pin doesn’t line up!

Note to self: Next time take off silencers #3 and #4; torque up properly with a socket; use washer shims to align split pin hole; paint in use split pin slot in axle nut. On next chain adjustment tighten to align split pin.

Did I get that wrong? Any better suggestions? :-\
« Last Edit: October 12, 2019, 03:58:44 PM by StevieWonder »
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Offline Nurse Julie

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Re: TORQUEING REAR AXLE
« Reply #4 on: October 12, 2019, 04:17:00 PM »
Blimey....that is tech. I couldn't tell you if its right or wrong as my brain is not wired for maths (other than Medical maths etc) or foreign languages. But.....stand on the spanner again until the split pin holes line up and you're done 👍👍👍 You really don't want to keep removing those 2 silencers everytime you adjust the chain, so this is a maneuver you would be good to master.
« Last Edit: October 12, 2019, 04:20:42 PM by Nurse Julie »
Im a Nurse, trust me, this won't hurt.....much !!!

LINK TO MY CB400/4 ENGINE STRIP / ASSESSMENT AND REBUILD...NOW COMPLETE
http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Offline Spitfire

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Re: TORQUEING REAR AXLE
« Reply #5 on: October 12, 2019, 04:36:53 PM »
I'm with the tool kit spanner and foot brigade.

Cheers

Dennis
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Offline Bryanj

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Re: TORQUEING REAR AXLE
« Reply #6 on: October 12, 2019, 04:38:34 PM »
And just keep going till the pin hole lines up NOBODY EVER used shims

Online K2-K6

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Re: TORQUEING REAR AXLE
« Reply #7 on: October 12, 2019, 04:42:27 PM »
Looks correct from calculations point of view.

I'd have gone 65 divided by 3 (36 inches equals 3 foot) gives 21.6 lb/ft with a 3ft lever or 1 yard in old money  :)

I do like your inclusion of one fat b'stard as part of the calculations though,  as I've got "one fat Pete the policeman" as a standard mate to help out with strenuous lifting etc.

Views on open ended spanner,  a Bahco adjustable will easily do that job and torque rating if you want to buy something generally very useful.  Very good quality.

The axle is more of a minimum torque rating to clamp the wheel sufficiently,  with the upper limit highly unlikely to be breached mechanically by then aligning the split pin. If you use the method of reaching the minimum torque setting, then turn further to match the split pin,  it's not going to give a problem.


Offline Trigger

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Re: TORQUEING REAR AXLE
« Reply #8 on: October 12, 2019, 07:42:46 PM »
You old boys worry too much.
As Bryan said, the holes never line up at the torque settings and that is the important bit  ;)

Offline Moorey

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Re: TORQUEING REAR AXLE
« Reply #9 on: October 12, 2019, 11:05:44 PM »
65 ft Lbs = a bit of a grunt as you pull the spanner. :D

Offline Bryanj

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Re: TORQUEING REAR AXLE
« Reply #10 on: October 13, 2019, 10:27:10 AM »
3/8 nut in elbow joint and when it flies out or hurts a lot youre there!