little marks on con rods

After my mishap I have examined everything fairly closely. the conrods have little marks across them that could have been on them from the start. The big ones when they were forged are pretty obvious too. I have now spent a few hours polishing both rods and they now look good. There was also a few that looked like the broken tangs on the locknuts had hit them.
Some one mentioned loctite wasn't in the manual. I suggest you all add it in.
Dereck

No pics ?

Loctite alters the lube applied to fasteners, and hence the applied torque - so what torque are you going to apply. ?

Funny too that its suddenly needed, 40 years on ??
And besides, the LOCKnuts have a locking function, from their very design.
If someone reused ? used ones, where exactly is the problem....

As Rohan says, locknuts should only be used once, torqued as per manufacturer with no locktite.
Unless someone's disagrees they will not fail.

This particular forum seems to have undue frear and poor uninformed opinion of the over robust Norton rods be they the regular one forged kind of the D-type two part rods so takes rather bad surface injury to weaken Norton rod, as you've proved by finding these instant rod still intake after decades no worry use. Still ya did a good thing to polish rods up/dn longitudinally. If engine has sezied in past I'd not reuse the bolts but nuts are one time use and should not need loctite. Best to measure bolt stretch than torque wrench to compensate for what ever lube or thread binding that may fool ya. So far as we know to date, Norton rods are so over built they do not have a fatigue life limit - as long as not over reving beyond redline so something else breaks first taking rods with them. Depending on which fastener reference to believe in, rod bolt stretch should be .006-.0065" and closer to 30 lbft torque than 25.

Its going to go back together with new bolts and nuts. Have no idea what the previous owner did or had done. I will use loctite as well and torque up to 25 foot pounds as suggested in the manual. I know they wont come loose after I have torqued them up and the loctite will be added security. The bike had done an unknown no of miles before I got it and I have dome about 24,000 miles on it. It was a surprise to see the nuts had come loose and I was lucky it happened 40 minutes from home and not in the South Island during the Rally.
Dereck

Adding loctite to dry bolts alters the torque value.
As you would expect, from adding lube to something.

Very easy to overtorque it doing that.....

And you'd then want to be absolutely certain that the loctite won't subsequently let go.
Since no-one has tested this concept as to long term reliability - yet ?

Norton Villiers sold little bottles of loctite with their own brand on it.
But didn't include it in the engine build procedure.
What does that tell us ??

I noticed in Mick Hemmings engine build video, when fitting the rod bolt nuts he says "I always put a spot of loctite on these" so I guess its fair to assume there's no issue in anyone else doing likewise.

Does Mick say what to do about the torque applied to the conrod nuts then ?

It is noted elsewhere that if the threads are lubed, then the applied torque needs to be reduced, by x%,
or they can be overtorqued. As also applies if they are oiled or greased or anti-seized, by varying amounts.

If someone also follows hobots suggestion and starts using 30 ftlbs instead of 25 ftlbs, then things could be quite overtorqued ?
Conrod eyes heading more towards oval than round ??

Hmmm, locknuts that need loctite to lock, what next ...

Duh these are the easiest bolts to measure stretch and is really what is being sought by various torque levels so get out the micrometers and crank till .006 @ ~25 lb ft or .0065 @ ~30 lb ft. Loctite should not be needed but no down sides if stretch measured. Go study up torque per size of bolt and grade then search up rod bolt stretch for lists-charts then select the one you like most for stretch to stop at.

So tell us precisely how U measure stretch on your conrod bolts... ?

There are dedicated rod blot stretch measuring device ya just slip in the bolt - i assume to decide to re-use or not but this works for me.

Have you actually compared rod stretch versus ftlbs torque, and run this engine, or is this just speaking ?

Yep I charted torque per stetch in stages which got severely tested in Peel's stone cold stuck throttle over rev event that ran another hard tested 2000 miles before biting bullet taking back apart to find rod bolts just like I left em, but crankshaft bend enough a ruler could measure, wipped off R exhaust cam lobe and cam tensioner, cracked off oil pump snout plus melted alternator resin out with some missing laminates ablated away which took Peel's sportbike spanking with huge winter screen zippity doda out. One of Peel rods had a nick I'd sanded and polished out in my 1st go through and was reused fine in Trixie Combat after her alu gasket rubbing on comma oil slot pistons let go and re-used again after a rod bolt left go identical to Herb Beckers blow up from a hidden fracture in bolt that corrosion gradually worked through metal grains about half way so cap came loose on low throttle 50 mph sight seeing level road speed. Peel sanded/polished rod still in Trixie now apart just to reseal from cracked carb boot grit inhaled ring blow by. Norton Rods are over built to have no fatique life limit within 150 hp and 850 rpm on factory cast iron flywheels as long tested by TC - who I spoke with recently and had little knowledge of current steel versions.