1997 Yamaha 40 HP starter/relay issue

[surlyjoe]

I have a 1997 Yamaha 40 HP C40TLRV. I've been having battery/starter issues. Sometimes everything works fine, sometime the engine tries but refuses to turn over. I replaced the starter and that didn't fix the problem so now I'm trying to replace the battery cables. When I took everything apart the negative battery cable was connected directly to the starter motor and the positive cable was attached to the starter relay. There was also a small red wire tied to the positive cable and attached to the relay. I put everything back the same way but nothing happens when I turn the key. I have a feeling the problem is something to do with the small red wire but don't know exactly what it does or why there would be an issue. I suppose its possible there is an issue with the relay itself but seems weird that it was working okay before. I tried connecting the positive cable directly to the starter and it worked so I know the battery and cables are okay. Any suggestions would be appreciated.