I can't find any info on the net regarding the markings of this bolt (left hand front mounting bracket to frame). Anyone here knows?
No, but if it's a frame mount bolt, I wouldn't think you'd go wrong with a high tensile flange nut.
I haven't come across that marking either
@Andre :confused1:
As KiwiCol said..If it's a frame mount bolt it will definitely be high tensile...I replaced all mine with stainless.
A new one on me I've not seen markings like that on any bolts before .
Only thing I can think of it's a Suzuki I'd mark for factory use.
Hopefully other might have a better idea.
:cheers:
Thank you all. :smile2:
Two new OEM bolts are arriving tomorrow. I will treat them as grade 8.8 as the marking is closest to the US grade 5 (roughly equivalent to 8.8). The "dot" on the marking is the identifier for the manufacturer. Why their are 2 short radial lines and 1 long instead of 3 long lines beats me.
The workshop manual specifies 50 Nm but it sheared at 45. As Seth said a long time back, when reusing bolts they might snap even when using the specified torque. I am also aware that there are engineering reasons to torque higher than standard. Grade 8.8 standard for coarse thread M8 is about 40 Nm (85% of proof load) and that is what I will use.
Sounds right to me. At 85PL you haven't reached yield yet, but I wouldn't be reusing them if torqued to 85PL. The markings are correct for a PC8.8 (800MPa) bolt.
The 50 Nm stated in the manual should be above 100 PL. Definitely not fit for reuse.
I didn't take into consideration that this bolt has a flange. That adds to the torque one can apply. Definitely a lot I have to learn about this but then :whatever:
This is an interesting topic (for me anyway) about Proof Load on a certain size bolt etc. Now how do we get on re-using our rear wheel nut over & over? We're loading this one over 100nm (110 - 120? from memory) How come this one is ok to do that to & a frame bolt, supposedly high tensile, shears at 45nm?
I didn't take into consideration that this bolt has a flange. That adds to the torque one can apply. Definitely a lot I have to learn about this but then :whatever:
Quote from: KiwiCol on Tuesday, 18 June 2019, 06:04 PM
This is an interesting topic (for me anyway) about Proof Load on a certain size bolt etc. Now how do we get on re-using our rear wheel nut over & over? We're loading this one over 100nm (110 - 120? from memory) How come this one is ok to do that to & a frame bolt, supposedly high tensile, shears at 45nm?
Good question. I assume it is not nearly as tightened in relation to its strength than this particular bolt and thus dosn't get stretched as much.
For a grade 8.8 M24 bolt a safe torque is 750 Nm. If you torque this to 100 Nm you should be able to reuse it many times.