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[timo482]

over torquing bolts in aluminum will always be a bad idea. the torque specs in the manual are for factory bolts - if you use bolts that stretch less or bolts that gall worse you will need to use less torque.

the weak part is almost always not the fastener its the threads in the aluminum. on stuff i hand fabricate [im making a steam service throttle in brass and copper right now] i prefer studs so the threads in the part are hardly ever moved. if I'm working in brass i solder smooth studs in so i can easily drill them out without having to go oversize if I'm doing aluminum i use a steel stud. i rarely use stainless bolts as the threads of the bolt will often damage the aluminum threads. use a very high quality stainless fastener and follow there torque guidelines to avoid aluminum thread damage. there are a few places on my harley where it comes with studs and nuts - i have redone a number of additional fasteners as studs and nuts. especially parts i end up removing a few times - ill get studs and nuts - the aluminum parts will last much much longer with a stud. it might not look flashy - but it looks like the mechanic actually knows what is going on.  steel drilled studs with stainless slit nuts and stainless wire - that looks the best. but i only do that on steam service stuff... bike stuff i use a steel stud, stainless nut.

to

[SAINTDANIEL]

diamond engineering has some fantastic stuff.

http://www.depss.com/

[donvito]

I recommend anti-seize when you aren't involved with an item that actually requires a thread locker.  Any time you have dissimilar metals, such as a steel bolt in an aluminum part, you will get corrosion where the dissimilar metals touch.  That corrosion is what tends to lock the bolt to the thread, which can then easily result in pulling those threads or stripping the head of the bolt when you try to break the bolt loose a year later.

As for the torque, folks need to understand that the important thing is the clamp load, and the torque reading is just an easy way to approximate a reading for that force.  When a manufacturer sets torque specs, it's done taking into account the materials involved and the type of joint.  The material of the fastener is important because each material has a different modulus of elasticity, and it's the stretch of the bolt as you tighten it that provides the clamping force.  Different materials will stretch differently, and will have different yield points (Highly Important).  There is also a difference if you're dealing with cut threads versus rolled threads, or a dry install versus one using a lubricant.  Those things affect the friction between the parts, which in turn affects the torque reading.  A tight fitting thread that's installed dry will reach the torque setting long before a similar joint with a looser fitting thread that's been lubricated.  If allowances aren't made for those things, you can wind up with the torque reading you want, but a very low clamp force, or a lower torque reading that leads to overstretching the bolt before you reach your torque spec, which can lead to stripping threads or even snapping bolts.

In other words, the torque specs in the manual are for a standard install using standard parts and following the standard method.  Change any of those things and yes indeed, you will most likely need to alter the torque spec to suit the new conditions.

Jerry

This is the only answer the OP needs to hear! Also, Alloyboltz is top grade American made and I have replaced every viewable bolt with their ARP Gr 8 12 points on the last 2 HD's and wont use anything else..