Yamaha Grizzly ATV Forum banner

1 - 20 of 32 Posts

·
Registered
Joined
·
382 Posts
Discussion Starter · #1 ·
What is the size of bolt that holds the rear rack on? Both the upper bolts (by the seat) and the lower bolts , where it bolts to the frame under the tail light.

Mine came right off and lost the bolts for it. Thing is I have a storage box and also take my girlfriend on the back lots of the time, she leans against it and over time I guess the rack just flew right off.
 

·
Registered
Joined
·
371 Posts
Most of the bolts on the chassis are 6x1.0 or 8x1.25.

6mm is a little under 1/4" and 8mm is right around 5/16". Eyeball it or measure with calipers & make an intelligent guess at the length.

Or, if you want it to look and perform like factory, order the factory bolts -they're the same price if not cheaper than what they rape you for at ACE hardware.
 

·
Registered
Joined
·
382 Posts
Discussion Starter · #3 ·
I went home and looked, its a m8 bolt in all 4.

Now just need to come up with a better solution for the passenger.
 

·
Premium Member
Joined
·
11,825 Posts
I went home and looked, its a m8 bolt in all 4.

Now just need to come up with a better solution for the passenger.
On my 660 the bolt are the same for both racks.
I used one at the hardware store to determine threads and compare for length. Used a lock washer too.
And yes, metrics are much more costly.
 

·
Premium Member
Joined
·
8,552 Posts
  • Like
Reactions: BDSNJ

·
Registered
Joined
·
371 Posts
Try Napa auto parts or a specialty bolt store -They're usually a lot more reasonable than a hardware store.
 

·
Premium Member
Joined
·
2,645 Posts
Home Depot or Lowes. There're only 4... Tighten 'em good....
 

·
Premium Member
Joined
·
8,552 Posts
Home Depot or Lowes. There're only 4... Tighten 'em good....
Any hardware store.
I know it is only a rack lucky the GF didn't "just flew off" with the rack:peace:
When in doubt torque 'em to spec. The white coat dudes spec torques for a reason.
Confucius if he had a torque wrench might have said "sometimes too tight is too loose"
 

·
Registered
Joined
·
382 Posts
Discussion Starter · #9 ·
Hardware store had the 8.8 head only, which looked close but only threaded in the first 2 threads. Off to the specialty bolt store, I need the one with just an 8 on the head.
 

·
Registered
Joined
·
371 Posts
The 8.8 refers to the strength of the bolt i.e. "grade 8.8", not the size. You are not going to find metric bolts in "grade 8" -those are SAE.

You likely need the same size bolt with a different thread pitch -the specialty store or Napa can help you
 

·
Registered
Joined
·
424 Posts
Yes, 8.8 is the grade of bolt not the size.
You need a M8 x 1.25. Not sure of the length but you should be able to ballpark it just by looking. The "1.25" is the pitch. This may be referred to as an M8 coarse bolt. Don't get an M8 x 1.0. That is a fine thread and won't work!
You can verify what the thread size is by running a metric tap into one of the bolt holes. Good luck!
 

·
Registered
Joined
·
382 Posts
Discussion Starter · #12 ·
its about an inch long, I'm going to bolt supply house later so I'd hope they would have it.
 

·
Registered
Joined
·
3,203 Posts
pretty sure the front rack uses the same bolts. couldnt you pull one of those, swap it to the rear, and if it fits, go get more?

im pretty stumped as to how a rack falls off.
 
  • Like
Reactions: BDSNJ

·
Registered
Joined
·
382 Posts
Discussion Starter · #14 ·
pretty sure the front rack uses the same bolts. couldnt you pull one of those, swap it to the rear, and if it fits, go get more?

im pretty stumped as to how a rack falls off.
Never had this issue til I got the girlfriend on the back... I ride it hard even with her on it, and the rack/storage is whats keeping her from sliding off the back.
 

·
Registered
Joined
·
3,203 Posts
i dont care how much weight you put on there, it still doesnt make sense. ive had my girlfriend back there, as well as myself, lots of weight, etc etc. something must have been wrong. bolts dont just magically unthread. they must have been SUPER loose and came out.. somehow all at once... or were somehow stripped or sheared? it really makes no sense to me. if they were loose i would think even the most unobservant rider would notice some serious rattling.
 

·
Premium Member
Joined
·
8,552 Posts

·
Registered
Joined
·
3,203 Posts
Let me be clear that the "lots of weight" was in reference to myself! Ohh man. That could get one in trouble.
 

·
Registered
Joined
·
3,872 Posts
I think out of safety for your lives the mods should delete your posts ... even if the risk is low it's still high risk ..
My rack bolts fell out as well and my wife is VERY SKINNY AND LIGHT Not much weight back their lol
 
  • Like
Reactions: idiggplants

·
Premium Member
Joined
·
11,825 Posts
Let me be clear that the "lots of weight" was in reference to myself! Ohh man. That could get one in trouble.
I'd like to hear what you say to your therapist.

Old Confucius was a Philosopher and a Politician, and he said all comedy comes from pain.
And, wives are girlfriends that understand and know a lot about bolts.
 

·
Premium Member
Joined
·
8,552 Posts
My Baby is very very hot ...the bolts must have melted!
 
1 - 20 of 32 Posts
Top