Main Fuse Blew at High Speed, cause?

[Val_kyri_e]

Just trying to figure out what may have caused the Main to blow at high speed, 5200 rpm. Bike had been running fine, Aired her out a little in 5th gear and at about 5200 rpm everything went dead. pulled off road and had power to nothing. after a few mIn's i check the Main fuse and it was blown, not melted like some others have had problems with just blown. did a quick patch (added a wire from post to post) ( I know - Not recommended) and limped her to the next exit, replaced the Main fuse and all is good. Put about 80 more miles on her and no issues. Question is what would have caused the Fuse to blow at high rpm's? Valkyrie standard with no addition electrics, just stock lights. Thoughts?   And Yes I now have a spare 30amp fuse stored just in case but would rather not have this happen again.  Thanks

[Ricky-D]

It could simply be an anomaly!

I would suggest keeping a few spares like you are doing and keep riding.

The only thing happening at high rpm"s is greater output from the alternator.

The battery should act like a voltage regulator and keep the circuits from seeing a greater voltage at high rpm's but that is with a good battery.

If you have a failing battery there would be a possibility of blowing that fuse if the alternator is really cranking out the current!

Nothing much to do but check out connectors for good connections, including the main battery connections,  and keep an eye out for any little precursors that may appear.

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[Pete]

Put a meter on the charging circuit and rev quickly to 5200 and note voltage.
Do the same test with amp meter.

If you find nothing, suspect defective fuse.   

[Skinhead]

If it happens again, I'd look for a wire rubbed through to ground, or pinched under a bracket somewhere.

[Val_kyri_e]

Thanks for the input guys. Just wanted to make sure i shouldn't be looking at something else. I will update if anything comes up but for now all is good.

[fudgie]

aint there a main fuse on the battery strap?

[Val_kyri_e]

aint there a main fuse on the battery strap?

My battery strap only had a 10 amp fuse on it. Could have been changed before i got the bike. The Main is a 30amp. I now have 2 pkgs of assorted fuses on her, just in case. 

[fudgie]

aint there a main fuse on the battery strap?

My battery strap only had a 10 amp fuse on it. Could have been changed before i got the bike. The Main is a 30amp. I now have 2 pkgs of assorted fuses on her, just in case. 

Yea I believe mine has a 30a in her. i'll have to run out and see.