Replacing bolts #4 or #7?

[Guest]

Hi,
Suzuki uses two bolts marked with a 4 or a 7. Does anyone know which can be replaced with stainless steel. I am assuming that #4 can safely be replaced with s/s, but was wondering what can replace the #7 which seems to be a high tensile type bolt? Or can anyone shed more light on this.
Thanks

[trippivot]

stainless is hard but is not hardened. the best thing is that it does not rust!!

last year at the drag track this guy had stainless bolts securing his rear sprocket and in the water box zzziiiinnnngggg all 8 of them sheared off.

engine covers are fine for 'em but keep the hard bolts where they are needed

[bwringer]

I'm a stainless freak from way back, but I agree -- use stainless only for low-stress applications, like case cover bolts (but NOT the case bolts that hold the upper and lower cases together).

http://z1enterprises.com sells nice kits that include all the stainless allen head bolts (AKA socket head cap screws) needed for the case covers on an engine. Make sure you use anti-seize.

http://boltdepot.com <== buy what you need, as few or as many as you like
http://mcmaster.com <== buy by the box, so you have extras!

[hampshirehog]

You can get higher strength stainless bolts. 700N/mm2 equates to Suzuki no 7s I believe and you can use these for bolting on your discs etc. These bolts in the UK are marked with a '70'. Or better still, if money's no object go titanium (I love the way titanium sometimes ends up with rainbow colours in the metal when it's welded).

[Matchless]

Thanks for the reply. Interesting on the higher tensile s/s bolts. I will try and find out if those are available here.
Again thanks as I only picked this #4 and #7 issue up today as I pulled a rusted bolt with the idea of replacing it with s/s on the front disks! It could have been a calamity!