Thinking of buying a "Polished Stainless Allen Engine Bolt Kit" for my KZ400

This may be a stupid question, but is there any reason not to do this? That is, replacing the old bolts with allen bolts?

Go for it. No reason not to. Old bolt heads get mangled. I did it years ago.  Stainless steel ones.

It is a good idea since sometimes the head of the screw is knackered.
This is because people think it is a phillips head when actually it is JIS [Japanese Industial Standard].
By selling your original screws you can recoup someof the cost.


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+1 Good idea - one of the best value upgrades you can make.

There are two reasons not to do this. One - the bolt heads will protrude a but more - I've never had any issues though.

The second is galvanic corrosion - aluminium and stainless steel are sufficiently different that galvanic corrosion can occur between the two metals. This is more theoretical than anything else - if we were talking about aluminium fasteners on large stainless pieces it could be a concern, but in practice stainless fasteners on aluminium isn't an issue.

Ceramic or copper anti size lube will block the galvanic corrosion between highest and lowerst level of the un-presious/presious metal.

wrote:

This may be a stupid question, but is there any reason not to do this? That is, replacing the old bolts with allen bolts?
 

Functionally? No. The Allen fasteners will be better in pretty much every way.

Visually? They will not look correct/original, but if you're not concerned about that then no worries.

I picked up a set for a 400 years ago and never used it; now it will go on a 440.