Hello, been making a Bobber out of a 2009 S40. Mounted the Regulator/Rectifier on the rear fender but had been tweaking it and recently ended up lowering the fender 1" because the it kept banging on the body of the bike when going over hard bumps and kept hitting part of the rectifier and fender. I had been riding the bike to work on a few occasions and it had been running fine (except for the above mentioned). Recently, after lowering the fender and test riding it the bike would not go above an idle without sputtering and backfiring out of the exhaust; no power, pickup, nothing. Made it home in 1st gear idling. Cleaned out all the jets in the carb and put the carb back in the bike. Went to start the bike and no electrics. Checked the fuses and one was blown. Replaced that fuse. Bike started right up. Everything appeared fine. Revved through the band. Took it out on the street and went through 1st, 2nd and 3rd. Everything seemed good and then IT happened. loss of power, nothing beyond idle except popping and backfiring. Made it home again in 1st idling. First thing I did was look at the fuse and it was blown again. MY question is -- Will a damaged rectifier/regulator blow fuses?

Quote:


if the battery is charged, it will run w/out the r/r
but w/out the battery, it won't run well even with a good regulator.

I'd start with the last work that you did and check the wiring thoroughly.

Found it! It was an intermittent short! Thanks. Went through all the wiring I did on the bike, rechecking everything. All the soldering, taping, etc. Some of the connections were made with "plug and play" connectors (the blue, pink, yellow kind depending on the size of the wire). Well, after checking the tail lights and rear turn signals, the front turn signals and headlight, the connections to the new neutral switch LED and left and right turn signal LEDs, the new speedo light, there was one wire left leading from the upper wiring harness down the neck and disappearing into the nether regions of the bike.  I had connected a pink plug and play connector to this wire and the 1/8" gap where the metal was exposed was in just the right position to tap on the side edge of the carburetor every now and again as the wire passed by it. THAT WAS MY PROBLEM! I made sure every plug and play connector was taped after finding that. Something as simple as that little gap caused a few days of chasing it down. But it is something I will always remember!