want to remind old sidecarists and newcomers to ALWAYS replace ALL sidecar mounting bolts and nuts with NEW GRADE 8 bolts and nuts.i made the mistake of using old bolts that came with the sidecar i purchased for my wife.the bolts LOOKED ok on the sidecar side so i only used NEW bolts on the bike side.im sure u know what it means to ASSUME they were good.
unfortunately for her,one of the sidecar side bolts snapped and caused her to have an accident that she will be paying for for quite some time!
PLEASE dont make the mistake i made and hurt yourself or someone else you love.Greg
Hopefully she didn't get hurt too hard.
To myself once the direction of my wife's Jeep sheared of. >> awesome to see the bus approaching you. A few days earlier and big part of our family wouldn'd be arround...
Since then I never bought again a used car from a so called mechanics, but prefered to buy used ones from tiny old ladies or new ones from the agency.
Hug your wife and stay at her side. (mine did so for 8 month and it is a debth I continue carrying on for very grateful)
Sven
broken bones in several places,but shes still with us.doubt shell want to ride again.my bad.this was her second sidecar,so it wasnt like she didnt know what to do.
I'd like some input from the machinists among us. A friend, who owns a machine shop, recommends grade 5's. He says an 8 will shear while a 5 will bend or stretch. Any comments??
Originally written by SidecarMike on 8/26/2009 9:59 AM
I'd like some input from the machinists among us. A friend, who owns a machine shop, recommends grade 5's. He says an 8 will shear while a 5 will bend or stretch. Any comments??
What he said has some merit but with the sizes we see on sidecar rigs if you stick with grade 8 you will be far ahead. Years back ont eh sprint cars we used grade 8 or higher 5/8" bolts for radius rod attachments and such. In a crash the grade 8 would sometimes break but not after totally destroying the mounnting spud on the frame itself.Some of us began using grade 5 and found that they would bend, usually not break and were not as bad at wiping out the area of the frame they were attached to. This train of thought was a good one but for other reasons. Of course not crashing woudl have been the best solution I suppose.
Bottom line..useing grade 8 bolts for sidecar mounts i sbest but grade 5 in 1/2 woudl be okay. I prefer 1/2". Metric? 8.8? Well okay but 10.9 woudl be best.
Nuts can be grade 8 or 5 as typically we are more concerned with shear than tensile strength. Nylocks or a nut with lock washer is okay. Nylocks shoudl really only be used once but it is common to use them over and over again. Some will say that no more than 3 threads shoudl be exposed past the nut. This is true if building airplanes but we are not doing that.
If using the all steel lock nuts only use them one time and then it is best to replace the bolt and th enut...not really practical for our applications.
I prefer grade 8 myself, don't care for nylocs. My experience with them is they tend to loosen just a little bit, that whatever there holdign moves but the nut looks tight. Prefer lockwashers if possible, and blue loctite.
Very good post.
I use 5/8" grade 8 bolts for attaching heim joints to the motorcycle on my leaner rig.
The other day I put the spacer incorrectly (bone-head move) and the outrigger interfereed with the mount and the motorcycle couldn't lean freely. I almost drop it during low speed turn.
That made me imagine what would happen if the bolt snaps at freeway speed..
Maybe I should renew grade 8 bolts from time to time?
Originally written by bluehdmc on 8/26/2009 10:52 AM
I prefer grade 8 myself, don't care for nylocs. My experience with them is they tend to loosen just a little bit, that whatever there holdign moves but the nut looks tight. Prefer lockwashers if possible, and blue loctite.
We use both. The lockwasher assembly is good in that it allows ease of assembly and does hold good. The downside is that the lockwashers really shoudl be replaced and noty used over and over. Lockwashers (the common kind) al;so do cut into the threads fromn time to time. Grade 8 lockwashers do last better than others.
We also use doubel nuts in many appications. I think I actually prefer this method if clearance allows it.
Blue locktite is also a good thing.
Most applications for mounts work well with coarse threads.
Just wanted to say thanks again to all the people providing us with their knowledge and experience to help keep us all safe. Since I still consider myself to be a newbee and a long way from being "experienced", the wisdom we all gain from each other without having to learn it from the school of hard knocks is appreciated. Had the sidecar off a couple times in the last year and never gave the nuts and bolts a second thought (other than periodically checking to make sure they were still tight.)
