| Author | Message | ||
     Fmaxwell |
I got a chrome bolt kit for the rear pulley off of ebay. It was a genuine Buell item and it came with the usual idiotic Buell installation instructions. The instructions said to remove the wheel in order to replace the pulley bolts. After the wheel was off, then you removed all of the pulley bolts and then installed all of the new ones. I did mine on a race stand, rotating the wheel and removing and replacing one bolt at a time from below the swingarm. Now the fun part: The manual says 35-37 ft-lbs torque to tighten. The instruction sheet says 45 ft-lbs. The instruction sheet calls for red Loctite while the manual doesn't mention Loctite. Since I truly believe that red is really for permanent bolts, I went with blue and then split the difference, tightening to 40 ft-lbs. Is it a difference because the new bolts are grade 8 and chromed? Is it because Buell came up with a revised torque spec? Is it just a typo? I'll probably never know, but it really is a pain having to wonder if you did the right thing. | ||
| Brent_crossbronkos |
I would have done the same thing re: torque. I have used blue on rear pulleys/sprockets for years and have never had a problem - you will have a problem with red loctite. Different fastener "finishes" have varying "friction factors" which is directly related to torque specs. This is a possible reason for the different specs you mention. You will certainly not have a problem with the 40lb spec you used. There are publications (don't have them handy) that list the amount of torque you have to increase/decrease for a given size of fastener depending upon that fastener's coating/finish (eg: zinc, cadium, plain,etc.) and what type of lubricant (if any) you are using. I have always wondered what the friction factor of the loctite is in order to modify the torque spec but have never found this info and years of experience has proven it not to be an issue (probably because the blue loctite is not very slippery - much like water). We call blue loctite "Harley Glue" in the industry. | ||
| Fmaxwell |
Thanks, Brent. Good to know that a pro would have gone the same way I did. I considered the issue of the finish on friction and reasoned that a highly polished chrome finish would have much less friction than the stock bolts with their rougher finish. If anything, I would have expected the chrome bolts to be spec'd to a lower torque. Given the absurdly high torque values specified for the Buell oil drain plugs, which also thread into aluminum, I figured that I'd be better off going closer to the lower torque spec. I used the blue gel Loctite rather than the more liquid stuff in a tube. It's just much less messy. I don't know what Harley uses, but I had to chase it out of the threads that hold the countershaft pulley guard in place. Every time I put in the bolt, it felt like it was cross-threading. I don't like chasing aluminum threads as it always makes them a bit looser, but sometimes it seems necessary. | ||
| Brent_crossbronkos |
"Every time I put in the bolt, it felt like it was cross-threading. I don't like chasing aluminum threads as it always makes them a bit looser, but sometimes it seems necessary." The Harley stuff seems to be yellow - don't know what it is. I agree with chasing the aluminum threads - must be careful. Sometimes a little brake clean and compressed air cleans out the threads enough to thread the bolts back in with little resistance. Always good to use a little blue loctite on all steel threads going into aluminum because not only does it keep the fastener tight, it prevents the build up of that white corrosion that forms between steel and aluminum (which makes the parts really hard to separate sometimes). | ||
| Perry |
I stripped out the threads on the bolts holding the primary inspection cover by carefully following the torque spec in the service manual. What the heck!!?? Then I noticed the spec was different in another place in the manual. Nice - thanks guys. Now I tend to ignore the spec and go with what feels right. Since doing so I have not stripped anything, nor had anything come loose. | ||
| Luxor |
I've noticed the same thing MANY times in my factory manual. Frustrating as hell when you do your own maint and anal about it at the same time.  I usually just split the difference if it's a couple of pounds either way. The most important thing is that they are all the same. | ||
| Brent_crossbronkos |
As a general rule we always torque any 1/4 x 20 (Coarse) bolt to 100-120 inch lbs, 5/16 x 18 (Coarse) bolts to 15-18 foot lbs and any 3/8 x 16 (coarse) bolts to 22-25 foot lbs. You will never have an issue using these specs - if you strip threads at these specs the threads were damaged anyways and would have given you trouble no matter what. These are the most common size threads on our bikes. Fine threaded fasteners are usually torqued a little higher, as are Grade 8 fasteners but if you read a torque spec for say a 5/16 coarse bolt and it is way off the 15 foot lbs you know you have a mistake/misprint. A search through almost any manufacturer's service manual will yield the same specs for these size fasteners - it doesn't matter if it is a Buell or a Chevy. Sizes not listed above should be looked up in your respective manual. "The most important thing is that they are all the same." - very true. That is why we torque almost everything in the shop. Note the difference between inch lbs and foot lbs in any specification and adjust your wrench accordingly. If your torque wrench is calibrated in inch lbs you will have to convert to foot lbs and vice-versa. Don't forget this crucial information. | ||
| Gentleman_jon |
Thanks for the information Brent. I might add, (once again), that developing a feel for proper torque is a skill every home mechanic should aspire to: When a bolt feels tight, it usually is, unless you are using an improper tool with too little leverage, or too much: ie: tightening a 1/4" bolt with an 18" breaker bar. Secondly, I recommend the use of a dial or beam torque wrench for the shade tree technician. The "Click" type need to be used properly, stored at zero, and loose feel just at the critical moment. A little common sense doesn't do any harm either, does it?  | ||
| Fmaxwell |
Brent, thanks for the advice on torque values. Question: Is that steel into steel, steel into aluminum, dry, anti-seize, Loctite Blue, etc.? I usually have more concern about the threads in the aluminum that the grade 8 bolt is threaded into. | ||
| Brent_crossbronkos |
"Question: Is that steel into steel, steel into aluminum, dry, anti-seize, Loctite Blue, etc.?" I assume you are referring to the general guidelines I posted. Under normal circumstances you can't go wrong with these specs. Steel into steel and/or aluminum isn't really an issue when it comes to the torque spec (I know- you think it would but it doesn't). The guideline is good for dry assembly, or blue loctite (the thin blue loctite doesn't seem to affect the torque much). If you are ever concerned about overtighening - err on the side of caution and use the lower spec. Anti-seize really messes things up - sometimes you need to reduce the applied torque by as much as 40% when using anti-seize. If you don't - the result will be a seriously over-tightened fastener! Once had a tech put anti-seize on the threads of a Porsche 911's wheel nuts at the shop and then torqued them to spec - the next time the car was in we had to replace all the alloy wheel nuts as the threads were all deformed due to overtightening. | ||
| Saintly |
I like to put anti-seize and red locktite in a bowl together and let them fight to the death! |
