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Which 450?
02-09-2007, 08:22 PM
I have had a few project bikes over the years, and on every single one, one of the idiots before me jammed a standard bolt in a metric hole. Probably because he had no idea there was a difference. So when I try putting the correct bolt back in, I end up having to retap it in some sort of way by heli-coiling it or welding it in and re drilling and tapping it, or going a size larger. So I thought I would post this little bit of information on the most commonly used types of bolts so people know what bolt to use, in case someone on here has a bike that turns into a project bike for me in the future..

1st off.. Standard bolts, YOU SHOULD NEVER USE THESE ON A QUAD, because there is only metric bolts on a quad, unless, in some cases of aftermarket parts, the part itself might use a standard bolt in the part, and only on the part, ie a end cap of a pipe,

These are the different grades of standard bolts and how to tell....

Basically, you count the tick marks, and add 2, that gives you the grade

If there are no markings, its a grade 2, this is a low stress bolt, should only be used in low stress areas, where no strength is needed
http://www.boltdepot.com/images/catalog/hex-bolt-standard.gif

3 marks, grade 5 medium strength bolt
http://www.boltdepot.com/images/catalog/hex-bolt-standard-grade5.gif

6 marks, grade 8 high strength, if its up to me, this is the only std bolt grade I'd use
http://www.boltdepot.com/images/catalog/hex-bolt-standard-grade8.gif

Then for Metric hardware, this should be the only type of hardware you should put on your quad, They have these at any hardware store (home depot, Lowes) or a fastener supply store (I use a local caterpillar parts store, they got everything, and the bolts say "CAT" on them it's cool.

I cant find any cool pics of metric bolts. But theres 2 common types "8.8" and "10.9" 8.8 is about the same strength as the grade 5 std bolts, and 10.9 is about the same as grade 8 bolts. It will say it right on the head of the bolt just like the std bolts have the tick marks, "8.8" or "10.9"

Now on to thread pitches, FINE and coarse thread, Standards thread pitch is found by the number of teeth per inch, Usually all the bolts in a bike that are wrong are "1/4-20" which is 1/4" diameter and 20 threads per inch. When it should be a "m6x1.0" the threads are similar, but the std 1/4-20 bolt is a slightly larger diameter and the thread pitch is coarser. Right now I cant remember how to find what the thread pitch of metric bolt is but I can remember that the lower the number, the more threads per length.

Any questions, comments, suggestions, or anything to ad?

CRich[814]
02-09-2007, 08:29 PM
nice writeup. easy to understand. i never knew about the 0,3,6 line markings.

Which 450?
02-11-2007, 12:12 PM
Yea I figured I would do some people a favor, but some are just too dumb to understand. I know a guy that had a 3/4" bolt as a drain plug. It stuck out about 3 inches. He went over a tree, it knocked it out, and cracked his cases.

02-11-2007, 12:18 PM
Originally posted by Which 450?
Yea I figured I would do some people a favor, but some are just too dumb to understand. I know a guy that had a 3/4" bolt as a drain plug. It stuck out about 3 inches. He went over a tree, it knocked it out, and cracked his cases.

wow some people just dont deserve quads

Which 450?
02-11-2007, 01:19 PM
Originally posted by Polak1035
wow some people just dont deserve quads

actually it was an 1985 ATC250r I think it cost him around $800 to have a shop fix the cases.

czrider263
02-11-2007, 01:38 PM
i hate it when aftermarket parts arn't metric. makes me go downstears to get the right tools. i keep all the metric stuff in my garage.

deathman53
02-11-2007, 08:12 PM
I have some american stuff with me because of that. The anti-fade hubs have a habbit of using american bolts, even more agrivating, just the allen head and not the bolt. Pro-design tethers use a standard head. Hyper beadlock rims use a 3/8 standard 12 point, thats agrivating in a tool box full of 6 point metric sockets.

1fst400
02-11-2007, 08:26 PM
the pro design teather took me forever to find an allen wrench that fit.

Rich250RRacer
02-11-2007, 08:57 PM
Originally posted by 1fst400
the pro design teather took me forever to find an allen wrench that fit.

I use a Torx for this, I can't remember what size, but I found one that fit perfect. I couldn't find a metric or standard allen that would fit.

eBone
02-11-2007, 10:22 PM
a metric bolt is measured crown to crown from one thread to the next. a m6x1.0 has a distance of 1mm from one crown to the next a m6X1.25 would be 1.25 mm. the lower the number the finer the thread

bone