I've been battling carb problems, fuel leaks, etc. Finally thought we had it solved but I can tell there is still a choke problem...at a certain point it RACES!
Anyway we had some half decent weather here last Saturday so I took all 3 bikes outside in the driveway and started them, took em' around the block. Problem: the Yamaha started, idled for a while and then started to sputter so I rev it a little. THe whole left side shut down or it sounded like it shut down. Then "bang"! I'm talking a backfire and I mean "fire". I shoot firearms and that backfire from the Yamaha made my .357 Ruger look like a sissy-boy flame. Yeah, I shut down the Yamaha. What the heck!
I know, I have the carb PDF and I've read through it guys but there's 1,001 different possible causes. Ideas? Why the backfire? Why the idle/start up/choke that wants to sputter or race? Can't believe it but I'm at the point where I feel like throwing a sheet over the bike and letting it sit for a year!
SgtSteve: Ethonal it could be, it causes all kinds of issues ! ( and clog carbs,) ,, but what do your plugs look like ? best to you,,, Preston
Yeah, ethanol is what the guy said that rebuilt most of the 81. Plus I think I narrowed it down somewhat; I had the bike sitting on the sidestand and from what I can tell there's a little bit of a fuel leak and it's weeping on the left side. So I'm thinking it's loading up the left side cylinder and BANG! Now I've got it on the center stand and we'll see what happens.
Another side to it all: I believe the leak is due to the petcock so if it's allowing gas to seep into the cylinder, well that could cause the problem.
Know if the petcock rebuild kits have material that won't disintagrate with the current fuel?
So fired it up again yesterday. Starts fine. Running. Don't know why I checked but the right side exhaust fine, heat building. THe left side, just air, no heat! I shut it down, pulled the plugs. Both were black as in "soot". Cleaned both and put em' back in and all was fine. I couldn't believe that the soot was bad enough that the left side wasn't firing, these plugs are new!
I still think there's something in the choke system that isn't right. Unless I let the bike run and heat up fully...if I rev the throttle the bike races...doesn't come back down. I have to let it warm up to the point where I can fully shut down the coke the whole way. I made a post in another section; ordered a petcock rebuild kit, getting some leakage.
r80rt: :)This is a splendid write up, THANK YOU!!!!
Dec 26, 2015 16:54:05 GMT -5
mashermoto: What the what is this shoutbox for? Or should I shout, WHAT THE WHAT IS THIS SHOUTBOX FOR!
May 12, 2016 22:22:21 GMT -5
motormike: Good Day ...just a FYI.. Wild Cat is this Labor Day weekend. Still go'n on. A few 650's still make the scene. Various rides at different skill levels each day.. awards dinner sunday eve. BS in the park'n lot after dinner.
Aug 23, 2016 7:57:01 GMT -5
lsettle: First post in over 6 years!
Aug 28, 2016 19:45:17 GMT -5
kardon: Wow quiet here, where did they all go.
Oct 7, 2016 2:18:13 GMT -5
gggGary: XS650.com LOL
Feb 16, 2017 20:49:02 GMT -5
buell88: Anybody have any idea who built the xs650 tracker used in the Draggin Jeans Ad on Pipeburn?
May 16, 2017 16:24:09 GMT -5
joshua: The regulator/rectifier unit I got from Mikes PMA has closer hole spacing than original. Are we supposed to mill the holes to fit?
Jun 7, 2017 19:25:58 GMT -5
joshua: My bad. I found the bracket they supplied to mount the rectifier/regulator... Uh oh. How is this meant to work? Which way is it meant to mount? Looks like I have to use some spacers or something. Good instructions would be nice.
Jun 7, 2017 22:09:52 GMT -5
craig8johnson: Not sure if this is the right spot or not but oh well...
Jul 11, 2017 18:04:15 GMT -5
craig8johnson: I'm checking the charging system. I'm afraid I might have fried the last battery. With the solid state regulator (after market) what should it be charging at. The book says, I think, 15 volts. I'm hitting 17 when revved. Is that too high?
Jul 11, 2017 18:06:19 GMT -5
gggGary: Yes 17 volts is too high, about 14 volts is max, sounds like you don't have the right regulator or it's wired wrong.
Jul 13, 2017 6:54:33 GMT -5
dean: Just saying Hello, new member who is going to fix up a 79 XS650 that has seen its better days. I will definitely have lots of questions coming up.
Jun 23, 2018 16:45:32 GMT -5
tt650: Trying to breathe life into a 1980 that's been stored (indoors) for 25 yrs. Air filters are dry rotted. Have cleaned carbs but she only runs briefly on choke then stops. Need jet setting info and other ideas that might help her idle and rev.
Jul 3, 2018 19:15:19 GMT -5
trix13: Hey everyone! New to the forum and am fighting those gremlins!! New charging system, ignition switch, coil and fuse box. Resistance is higher than normal on the ignition pick up so I'm trying to find one. No such luck yet.
Aug 16, 2018 8:50:48 GMT -5
trix13: Also, even though all of my connections are clean, I cannot seem to find out why , when at higher rpms, I hit the signals and the rpms pulse with the signals...hahah. same with the brake light. I appreciate all input!!
Aug 16, 2018 8:55:08 GMT -5
bob99: how do I post a question. I am new to the forum
Jun 6, 2019 10:52:10 GMT -5
adlpc: Hello all! Been enjoying your edifying posts and discussions - and as a fan of the XS650 since my early teenage years happy that I now own a 1980 Special which I plan to turn into a vintage half faired racer. Thank you all for being here!
Oct 1, 2019 0:58:56 GMT -5
jimothyj: Hello everyone, I just joined & wish would have known about this site in 2014 when I brought my 1974 TX650A back from the grave. I have spent a good deal of $$ and alot of time on it. Just painted it and working on electrical, I will post pics soon,
Apr 10, 2021 2:14:13 GMT -5
louisvan: trix13 - I had a problem with my 1975 SX650. When I got to highway speeds, the engine lost power. The problem was in the connectors. At a certain vibration and the wind pushing on the wiring loom, the connector lost continuity. A bad crimp to the wire.
May 20, 2021 1:19:09 GMT -5