Torque Wrench ?

[Stephen Foster]

Hello ,
I wonder if a knowledgeable forum member might help by letting Me know the most appropriate torque wrench for working on the A10 please as there are many available with differing torque settings ?

Thank You in advance ,
Steve..

[RDfella]

I prefer the hand type. It has various 'settings' whereby handtight, tight, very tight and bl**dy tight are achieved by feel and experience. I usually mutter 'click' when the appropriate setting has been achieved. Seriously, though, whilst these bikes belong to an era where torque wrenches were a mystery, using them on BE and cylinder head bolts (especially the former) makes sense. A small 3/8 drive torque wrench is all that's needed for these bikes. Being an old geezer I prefer ones calibrated in lb-ft to save me converting from newtons etc.

[Greybeard]

I only use a torque wrench for the cylinder head bolts. The tool is the clicky type but it's never been checked for accuracy. I'm more interested that it will apply the same torque to each bolt.

If you are experienced with spanners you know when something is tight enough.

In the days when bikes were 'maintained' out on the road, by dad, who had a pipe wrench and an adjustable spanner, nuts and bolts had to take their chances.

[Stephen Foster]

I prefer the hand type. It has various 'settings' whereby handtight, tight, very tight and bl**dy tight are achieved by feel and experience. I usually mutter 'click' when the appropriate setting has been achieved. Seriously, though, whilst these bikes belong to an era where torque wrenches were a mystery, using them on BE and cylinder head bolts (especially the former) makes sense. A small 3/8 drive torque wrench is all that's needed for these bikes. Being an old geezer I prefer ones calibrated in lb-ft to save me converting from newtons etc.

Thank You ,
Could You please let Me know the Ft ?lb wrench required as I have sourced one but am unsure of the torques required ?

Regards,
Steve..

[RDfella]

Apparently the torque setting for A10 cyl head bolts was, according to BSA,  "really tight". No lbs-ft specified, 'though the consensus today seems to be around 30 lbs-ft. Big ends vary 8 - 22 lbs-ft depending on model. Thunder rods are much higher. Can't recall now, but it's over 40.

[berger]

thunder rods 42ftlbs , cylinder head 30ftlbs on ally head leave it a fortnight while you go to your villa in wales and when you get home give it 34ftlbs and jobs a good en   or if your me pull it down leave it 3 days while i go on a bender then throw the torque wrench in the autojumble pile get the 3/8ths drive ratchet tool thing and feel the force. once this is done no blowy head gasket or have been lucky

[muskrat]

G'day Step.
I prefer the beam type. I have two, one 1/2" drive goes from 15ft/lb to "need a length of pipe" and a 1/4" drive for inch/pounds (up to 10ft/lb).
Cheers

[Minto]

I’ve had a pair of Halfords torque wrenches for a few years, bought them before I had the BSA, but they cover everything I need to do on both my bikes, my car and my van. Really nice to use, not cheap but not Snap On price, and are sold with a calibration certificate (for whatever that’s worth).

[Colsbeeza]

Hi Stephen,
Like Muskrat, I have a 1/2" drive which goes up to about 120 ft-lbs, and a small 1/4" drive which goes to 24 Nm or about 20 ft-lbs for the smaller nuts. I bought it for the oil pump studs which are 1/4" Cycle Thread - easy to strip if hamfisted.
The cush nut and clutch nut need to be f'n tight - 65 ft-lbs recommended, but I use an impact driver for those.
The 1/2" drive ones can be cheapies with internal ratchet, but have a reputation for serious errors. Muskrats beam type is much better.
I have attached a Conversion chart for torques, and also settings for the A65 which Kiwipom posted here some time ago.
BSA didn't publish torque settings for the A7 & A10, so the A65 settings are a good guide.
Col

[Greybeard]

I tighten all the head bolts to 32ftlbs then go round cracking them off and bring them back to the same torque, taking care to not allow the movement to stall. I had some thick washers made for the head bolts.

[a10 gf]

Funny to see al the models available :O) > https://www.amazon.com/s?k=torque+wrench

Personally got 2 cheap (20\40 euro) 'click' wrenches, one small and one quite big, covering anything I ever needed to do accurately.

Upon the time when I was working with oil industri mechanics\electronics, did bring them to our workshop to compare with the supercalibrated superexpensive stuff in use there, my cheap ones were 'close enough' to be used for any of my personal work without fear of inducing any error of practical siginficance.

In this day and age, I'd surely buy some digital model.

Once knowing a wrench to be trustworthy, always slacken the spring (set to zero) after every use, then they will stay reliable for a long, long time.

& a handy little conversion table > https://www.a7a10.net/forum/index.php?topic=2452.msg15852#msg15852

If buying a 20 euro wrench and wondering about accuracy, then simply buy this as well > https://www.amazon.com/Professional-Digital-Torque-Wrench-Tester/dp/B07MKJZSKK/

[Minto]

As A10GF says…
Once knowing a wrench to be trustworthy, always slacken the spring (set to zero) after every use, then they will stay reliable for a long, long time.

I was told to also avoid using it to slacken nuts n bolts off.

[BSA_54A10]

The deflecting beam type shown in Musky's photos are the only ones worth using
They will remain in caligration almost indefinately
The spring loaded micrometer dadjustment type go out of calibration very easily
We did the head gasket on Shanes 554 Inter .
All went well till two of the head bolts broke
When we checked Shanes spring type against my defecting bar, it was reading 40 lbs low at 120ft lbs so no surprise that the bolts let go before getting to 145 ft lbs
His was still in the wooden box and always backed off after use but the springs had still gone off .

Similar to Musky I have an 6" , 8",  10" & 12" for motorcycles
Then there is a 18" for the vans plus a 24" & 36" for tractors .
Those last 2 are Britool micrometer adjustment  &  calibraed every 10 years or so
For critical applications you only use the middle 2/3 as they usually remain good.
If you regularly use one that is near the length of your wratchet handle you will quickly get the "calibrated elbow "

[RDfella]

When we checked Shanes spring type against my defecting bar, it was reading 40 lbs low at 120ft lbs so no surprise that the bolts let go before getting to 145 ft lbs
His was still in the wooden box and always backed off after use but the springs had still gone off .

Doesn't make sense to me - surely if the spring had gone 'tired' (which is highly unlikely if backed off after usage) the reading would indeed be low - eg a reading of 120 lbs ft would give you less torque (80 in this case) not more? The sheer amount it's out would point to me that there's summat wrong with that wrench other than the spring.

[Rex]

The deflecting beam type shown in Musky's photos are the only ones worth using
They will remain in caligration almost indefinately

Only because there isn't adequate calibration techniques for the bendy beams.
Accuracy in use for this type depends on the skill and experience of the user, whereas the pro's use the click stop type as the torque applied will be the same for every fastener whether you're even looking at it or not.
Rocking up to a skilled assembly workshop with a bendy beam would guarantee p*ss-taking on an industrial scale.