Julian H Posted March 19, 2015 Share Posted March 19, 2015 HiWhat is the correct torque to do up my new Apollo alloys please?Thanks, Julian Link to comment Share on other sites More sharing options...
DJ. Posted March 19, 2015 Share Posted March 19, 2015 Caterham say 74Nm for wheel nuts, and I would assume this applies to any wheel.Duncan Link to comment Share on other sites More sharing options...
Julian H Posted March 19, 2015 Author Share Posted March 19, 2015 Super thanks Duncan Link to comment Share on other sites More sharing options...
ECR Posted March 20, 2015 Share Posted March 20, 2015 If your wheels have steel inserts under the nuts, the torque needs re checking after a few miles as the inserts can sink into the castings Link to comment Share on other sites More sharing options...
Smithy77 Posted March 20, 2015 Share Posted March 20, 2015 Anyone else feel that the standard Caterham wheel nut torque is too low?? Most other cars are 105Nm I believeWhen I first used 75Nm, the next time I came to take the wheels off, a few of the bolts were alarmingly loose - barely more than finger tight! Since then I have gone to about 85Nm and not had the same issue Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 20, 2015 Member Share Posted March 20, 2015 I've never had a problem (although it does remind me of an old joke). But when you say "bolts"... what's your set-up?Jonathan Link to comment Share on other sites More sharing options...
John Vine Posted March 20, 2015 Share Posted March 20, 2015 I've always understood that torque settings should be reduced (by maybe 30%) if the fastener is lubricated (say with copper grease), on the grounds that applying the specified (dry) torque would likely cause over-stretch.Is this correct? Perhaps the engineers out there could comment.JV Link to comment Share on other sites More sharing options...
ECR Posted March 20, 2015 Share Posted March 20, 2015 Wheel nut torque as recommended by manufacturers is variable for reasons I dont understand fully.A joint should be torqued up to a point that stops any movement between the 2 faces. Movement caused by the stud stretching (due to insufficient torque) and then relaxing (however small) will lead to eventual fatigue. Given that the studs are all generaly made of the same material why is the torque on my Lotus Elise 77ftlb and on my Caterham 40/45 ftlb given that the diameters and pitches of the threads are the same. I can't accept that I load the wheel joint more on my Elise than my 7.If you think of a nut/stud joint as if it were a tension spring holding the 2 faces together then you can stretch the spring to tension the joint (which is what you are doing to the stud when you torque up the nut). If my Elise stud/nut set up can take 77ftlb then for sure my Caterham can take the same, as that sort of loading isn't overstretching the spring (going past the studs yield point).Perhaps it's something to do with the hub's ability to accept the loads put into the stud,Not convinced Link to comment Share on other sites More sharing options...
ECR Posted March 20, 2015 Share Posted March 20, 2015 The convention is that torque figures assume a "lightly oiled" thread (which is nicely vague)Torque is only a general guide to load in a bolted joint. The only accurate way to asses load is to measure the bolt extension (which is why critical joints like big end bolts on high performance engines or the top of nuclear flasks for instance are measured not torqued) Link to comment Share on other sites More sharing options...
Martin J Posted March 20, 2015 Share Posted March 20, 2015 .......and then you throw locking wheel nuts into the equation.I don't have these fitted to the caterham but they are on the tintop wheels. Recently had some new tyres fitted by a good local independant tyre place & watching him torque up the wheel nuts (with a torque wrench & not just an air gun) he missed out the locking nut & did that by hand with a shorter lever.I asked why & he said they have had a number snap over the years when torqued right up so they go a bit more gently with them. Link to comment Share on other sites More sharing options...
Julian H Posted March 20, 2015 Author Share Posted March 20, 2015 New wheels on my wagon! Thanks gents. Will re torque after each of the next few outings just to be sure Cheers Link to comment Share on other sites More sharing options...
Nigel Fox Posted March 20, 2015 Share Posted March 20, 2015 Nuclear fuel flask lids (UK AGR) are bolted and tightened to a torque figure. Link to comment Share on other sites More sharing options...
Martin J Posted March 20, 2015 Share Posted March 20, 2015 If one should come off, odds on it will be the nearside, oops. Link to comment Share on other sites More sharing options...
Martin J Posted March 20, 2015 Share Posted March 20, 2015 Hope to see them on a blat soon Julian. Link to comment Share on other sites More sharing options...
Julian H Posted March 20, 2015 Author Share Posted March 20, 2015 Trust you are still enjoying the Brooklands Martin? I re-fitted my Aeroscreen a couple of nights ago. Link to comment Share on other sites More sharing options...
Martin J Posted March 20, 2015 Share Posted March 20, 2015 Oh yes. Link to comment Share on other sites More sharing options...
Smithy77 Posted March 20, 2015 Share Posted March 20, 2015 I meant nuts of course! Link to comment Share on other sites More sharing options...
ECR Posted March 21, 2015 Share Posted March 21, 2015 I wouldn't want to live too close to a nuclear flask which had been torqued down. My experience is that joints of this nature are made with hydraulic bolt tensioners. (my company manufactured them .....)Perhaps cost cutting strikes again ! Link to comment Share on other sites More sharing options...
John Vine Posted March 21, 2015 Share Posted March 21, 2015 and then you throw locking wheel nuts into the equation.Back in November, I went to fit my winter tyres (steel wheels) on my Mondeo. The alloys come with locking nuts. I tried the first one but simply could not shift it, even with a breaker bar. All I succeeded in doing was mangling the ridged key. The other non-locking nuts were also very tight but they came off OK with the breaker bar. (Ford's specified torque is a whopping 140Nm.)The wheels were last removed/refitted by the local Ford dealer during the annual service. I took the car into them to explain the problem to the Service Manager and to ask for his advice. The upshot was that although they managed to shift the other three locking nuts, they had to resort to welding a nut onto the recalcitrant one in order to remove it. I pointed out that I'd lubed the studs lightly with copper grease (as I've always done). Could it be that his mechanic had not made any allowance for the lube and simply overtightened the nuts, I asked? He didn't answer the question directly, but he did fit my winter wheels for me and supplied a new set of locking nuts, both FOC. I guess he was inviting me to draw my own conclusion.JV Link to comment Share on other sites More sharing options...
Area Representative Geoff Brown Posted March 21, 2015 Area Representative Share Posted March 21, 2015 55 lbs/ft in 'old money' for all wheels.But check torque after about 200 miles. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 21, 2015 Member Share Posted March 21, 2015 I've always understood that torque settings should be reduced (by maybe 30%) if the fastener is lubricated (say with copper grease), on the grounds that applying the specified (dry) torque would likely cause over-stretch.The important point for end users like us is that you don't change from the conditions used when the torque settings were specified and expect the same setting to remain appropriate. Changes that could affect the appropriate setting include lubrication, materials and fasteners such as washers.When I first used 75Nm, the next time I came to take the wheels off, a few of the nuts were alarmingly loose - barely more than finger tight! Since then I have gone to about 85Nm and not had the same issueThat's very unusual. I'd have a good look at both threads. Open or closed nuts? What sort of wheels? How much stud do you have protruding from the hub?Jonathan Link to comment Share on other sites More sharing options...
Smithy77 Posted March 22, 2015 Share Posted March 22, 2015 Jonathan - I have closed nuts and standard 13" superlight wheels. I have noticed the the rear or front have slightly shorter stud threads, I forget which, possibly the rears slightly shorter. Is this not normal? Link to comment Share on other sites More sharing options...
Julian H Posted March 22, 2015 Author Share Posted March 22, 2015 good man! Link to comment Share on other sites More sharing options...
SM25T Posted March 22, 2015 Share Posted March 22, 2015 When I bought my 7 from CC it was 4 years old. 32mm long studs fitted. They barely engaged 3-4 threads in the nuts. CC maintained this was safe. I wasn't happy and replaced all studs with the 40mm long ones. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 22, 2015 Member Share Posted March 22, 2015 I think that what SM25T describes is quite common.This was recently discussed here, but for open nuts. There is a rule of thumb that engaged thead length should be a minimum of 1.5 x bolt or stud diameter. (For closed nuts there's also the potential problem that the recess isn't deep enough for the length of stud.)Jonathan Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now