What's the deal with grade 8 bolts on passenger pegs? Isn't a grade 5 plenty strong to hold anyone? I see HD's Sportster passenger kit comes with grade 8, which I (most likely) won't be using since I am extending the mount slightly if needed. When I look up spec's of grade 5, they are quite high already. Shear strength & tension strength are way past the limits of even the heftiest of people. Here's a few links I read (briefly) a while ago:

http://www.rockcrawler.com/techrepor...ners/index.asp
http://www.boltscience.com/pages/faq.htm

 

I trust the MOCO engineers' specification.

 

I think there is more to it than passenger weight. What if it gets clipped or if you drop the bike? You dont wwant that part to break off.

 

first person to break a grade 5 would sue because it wasn't grade 8.

 

Think about how much multiplication a lever generates.

I don't know how shear-strength is calculated, but I doubt it was at the end of a 5-inch lever.

I can't imagine the MoCo would give away Grade 8s if they could get away with using Grade 5s.

 

^True. Maybe for if the bike is laid down on it's side the pegs help relieve some of the bikes weight?

 

Generally speaking a grade 8 will snap before it bends. Though, start throwing S.S, higher level grade 5's in to the mix (that about match lower grade 8's), and it can become a headache to sort LOL.

 

The Moco uses the cheapest and lowest quality parts it can get away with. They use the supplier with the lowest bid that meets the as less a quality part standard it can. As does Honda, Kawi, and the others. It's a fact of manufacturing and business. Especially one that makes a high volume assembly line product.

 

That may be true, but I'm just talking about bolts here.

 

There are more than a few places that you want to use Grade 8, foot peg mounts are one of them. There are multiple considerations-leverage, hitting a bump hard with all the weight on them, just to name a couple.

Another place is the handlebar riser bolts. Saw a pic last week where the handlebar riser bolts snapped on a bike that had apes with some Chinese or Taiwan risers...dunno if the aftermarket riser bolts were grade 8 or not, guy was going 60 mph when he hit a good size pothole and was lucky to make it to the side of the road with the handlebars no longer connected to the forks.