starter clutch bolt question

[tothemax93]

So long story short, I thought I ordered 3 new bolts for the starter clutch and wound up getting one. My mistake:bang head: I called about getting the other two. They said It would take a week or better to get them, and I have a guy set up to help me change it this week. So I figured I'd try to find some bolts locally.
Another long story short, I found the exact bolt, except for the numbers on the top. I'm assuming the numbers represent the hardness.
The bolt from yamaha said 10.9 on the top. The bolts I found said 12.9 on top. Is There any problem with using the bolts I found, or should I get the factory ones?
By the way,I found the same size bolts at Fastenal
thanks, Tim

 

[Rusty McNeil]

So long story short, I thought I ordered 3 new bolts for the starter clutch and wound up getting one. My mistake:bang head: I called about getting the other two. They said It would take a week or better to get them, and I have a guy set up to help me change it this week. So I figured I'd try to find some bolts locally.
Another long story short, I found the exact bolt, except for the numbers on the top. I'm assuming the numbers represent the hardness.
The bolt from yamaha said 10.9 on the top. The bolts I found said 12.9 on top. Is There any problem with using the bolts I found, or should I get the factory ones?
By the way,I found the same size bolts at Fastenal
thanks, Tim

My guess is they are hardness, it's just a guess tho', I'm used to a grade 8 being about the hardest thing around so not sure what a 10.9 or 12.9 could be.

If you replace them with a much harder bolt then they might be more brittle and less giving, which could lead to premature failure possibly.

Seamn Morely would be able to better answer this than me tho'

 

[tugla]

you are correct they are hardness scales for metric bolts. a 8.8 metric is about a grade 5 bolt.

 

[one2dmax]

The 12.9 is about as hard as you can get and will work just fine for you. It may be slightly long and if so you can check and see if it will hit (a little longer is fine). You can always sand or cut down the bolt too.

Sean

 

[tothemax93]

Thanks Sean,
The bolts from Fastenal are pretty much dead on with the factory bolts. I was really suprised to find such a great match. The salesman wanted me to take the whole bag with 100 bolts. I talked him down and he let me just take a few of them. If I would have taken the hundred, they would cost .37 each.