Topic: CB750A fuses

[econguy48]

My 1976 CB750A with windcutter fairing has three 7Amp fuses and two 30Amp in the fuse box. The bike has seen a lot of storage time ------- it only has 7500 miles on it and has always been faithful. The 30 Amp blew recently and I replaced with the other one to get the bike home.   My problem is that, from what I've read, the bike should have 15 Amp fuses instead of the 30Amp. Yes? No? It looks like the fuses that are in there have been there since day one.  Any help would be appreciated.
Econguy48

[raymond10078]

The wiring diagram in the Owner's Manual specifies a 15 ampere fuse for the Main.

[JimS63]

Yep 15a main and the other two are 7a. These old bikes blow fuses because the wiring overheats due to poor connections. Check behind the fuses on the fuse block to make sure that the fuse block is not melted as well. Mine was and I had to make a whole new fuse block using a generic one I bought at a parts store. With the new style blade fuses (and cleaning up alot of the connections) I haven't had a problem since!

[raymond10078]

Since you have a '76 - you do have five fuses - but only three are in use, the other two are spares.  The 77/78 models use a different fuse block - the spare two are in the cover.  The 76 - at first look - appears to have five active fuses.  I recall that the top/bottom are spares.

[econguy48]

The fuse block seems ok but the fuse didn`t appear to have shorted out but rather had melted away from one of the contact ends of the fuse -- probably a sign of overheating rather than an electrical fault. Now that the snow is starting to fly, I think I will install a blade style fuse block. Thanks for the help.

[Mr Freeze]

My old fuseblock looked like this and the P.O. had installed an inline fuse in the place for the mains.



I've since switched out to this.



Nice thing about the blade fuesblocks is that they're easier to come by and mount in the stock position without a lot of effort. You can throw some extras in a pouch under the seat and don't have to worry about breaking them. I was able to clip the old fuseblock wires and crimp on insulated spade connectors without much loss in length. The 6 pin connector remained the same on the other end.

Got the block at wiringproducts.com

[raymond10078]

Another option that is "plug and play" is from Hondaman (he supports this forum, too):

http://sohc4shop.com/catalog/product_info.php?manufacturers_id=12&products_id=48&osCsid=391e5d1ce3bf105ce319992b56c1c130