Years of experience can certainly teach you the correct 'feel' for the ideal torque for a given fastener. I rarely use a torque wrench myself other than for critical stretch bolts used in connecting rods etc. Over the years I have won a few bets with people that I can hand tighten within a couple of ft/lb of the required tension.
There is a certain point where the resistance increases very suddenly.... when you learn to feel it you're pretty much on the spec.
I hear this alot in many trades. I'm a Plumber and Electrician. Many of the codes call for torque settings that pretty much anyone that has been doing it for awhile will simply ignore. It's not so much arrogance of the skill, but getting a feel for it's intended use and the materials used. Different qualities of copper and plastics will except torque better then others. Experienced hands have a feel for what the materials you are putting under pressure are actually doing.
A good example is hydraulic pumps. Large ones have torque specs listed that are entirely useless. Red permatex can be your best friend. Fittings calling for 35 fp's of torque will sometimes require less force to seal properly, but most times due to quality of seals and machining of the fittings, more is required to get a proper seal. Turn the wrenches long enough, you will grow to understand what your wrench is telling you and getting close under many circumstances is better then what the books are telling you.
I doubt your mechanic is just being a lazy ass about the important parts like crank bolts and such, but probably experience has shown him how to feel his way through the rest. Alot can be said for the ability to feel the subtleties and finesse of the materials used simply from years of experience.
I'd be more worried about his explanation of why he doesn't use a torque wrench.. That's an arrogant ass answer and arrogant asses mess stuff up because they think they know everything.. I'd find a new mechanic...
There are some nuts like the tensioner pulley on the timing system, which are impossible to get to with a torque wrench without pulling the motor out. So ya, you're doing that by hand, so its good to know what certain torque figures feel like with a wrench.
Almost everything in a motor needs to be properly torqued. But most everything else can be tightened by hand if you have the experience and understand what a certain tightness should feel like.
Tell ya one thing, working on someone else's bike, I always torque everything to spec. Last thing you want is to have someone's bike fall apart because you tightened by hand.
I worked in automotive for years and can second the comments of many from here. After experience you can feel the point at which most fasteners have a significant increase in resistance and most times that is right at the torque spec. For torque to yield hardware a torque wrench is ALWAYS used. safety critical hardware is also a must for the torque wrench. Any sealing surfaces are also important to torque as they can become warped from over torqueing and create a permanent leak. With experience comes an understanding of the feel of different torques and the optimum torques based upon hardware size and material. Many times I torque by hand and recheck with a torque wrench if it is non critical. Again, this comes with an active interest in improving ones skill with experience; nit just years on the job. I had known many techs with years of experience and not a single day of actually doing their job with any skill, simply because they don't care. There are many shop jokes about listening for the click in the elbow, the German method (goodandtight) and the American standard (Armstrong), or customer induced failure (loose nut behind the wheel). But a professional keeps these jokes in the shop especially when talking with a concerned client.
If you are not comfortable with your tech, find one that you will be. it is your money and your life.
Ed: "hey Peet, what was the clamping requirement on that gasket?"
Peet: "the spec says 50lb/in^2, since the cover is thin, make sure you don't space out the bolts too much or it won't sit flat"
Ed picks a bolt diameter / length / threads / material that meets a bunch of design requirements (how long can it be? What material will it be in contact with? Will it get hot? Will it be exposed to chemicals?), uses a little equation and finds out how much torque must be applied to get the desired clamping force.
Then he needs to make sure the bolt he picked and the material its threaded in can take that load. If not he needs to go back and pick something else.
I will say this after almost snapping one of the bolts (out of 4) on the cover for the oil screen while using a torque wrench. If it wasn't for feel I would of been world of hurt, I don't care what the manual says I dialed it down a few..
1 - 20 of 24 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
A forum community dedicated to Ducati owners and enthusiasts. Come join the discussion about reviews, performance, modifications, superbike racing, riding gear, classifieds, troubleshooting, maintenance, and more!