Nysmanxs400 Posted October 9, 2011 Share Posted October 9, 2011 Hello, everyone I've been reading this forum for a few weeks now. Kinda wish I found it before I got the bike but oh well. So, I've got a 1982 Yamaha xs400 it's gonna be my first bike. I say gonna because 1 I haven't taken the course yet and 2. It needs a little work to be street legal and road ready. I got the bike first because it was a really sweet deal old guy who works on motorcycles/atvs/ gocarts drives it to town and his mailbox (he's in the country) but wife says it's gotta go so he sold it to me cheap (to stop her nagging lol). Ok enough back ground on to the bike it's got a slight leak on what i believe is the rubber air cleaner joint (thats what the web says it is) not bad but not good. But then after a series of unfortunate events it started leaking oil heavily from the kickstand and chain traced it back to what I believe is the Air Cleaner assembly (agian the web says that) noticed a hole in the box. My first question is a "dumb" one, why is there "oil" in an "air" cleaner? And 2, the hole in the assymbly seems like it was desgned that way is there a plug missing? Bonus: Is the major oil leak cause for the major power loss and white smoke when reved up? Thank you all in advance for your help. Link to comment Share on other sites More sharing options...
up.yours Posted October 9, 2011 Share Posted October 9, 2011 hi, and welcome to the madhouse, nice intro, it/s just a pitty that no one on here has a clue about motorcycles, (only joking) im clueless , but i should imagine our drewpy will jump in with both feet , and help you out. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted October 9, 2011 Moderator Share Posted October 9, 2011 sounds like the engine is overfilled with oil, big style! with a kickstand means the 82' would be an SOHC, which is right at the end of that production run (DOHC's came in at '81) you may have a sight glass on the right hand side, with the bike level and not on side stand, it should be half way up the sight glass! check out ww.xs400.com too Link to comment Share on other sites More sharing options...
Nysmanxs400 Posted October 10, 2011 Author Share Posted October 10, 2011 Thanks drewpy, I have put quite a bit of oil 4qauarts this week in it since it has that small leak, then started leaking major oil I was paranoid about it seizing. Just checked the sight glass (didn't know it had one lol) is completely full. Without a dipstick I was just best guessing the oil level since it didn't have a gas gauge figuered my oil light was my oil detection. Yesterday, I sealed the hole and put 2 quarts oil in guess I'll unplug it and let the oil drain to a normal level and keep an eye on the sight glass. Thank you again for the help. here is another Q, the P.O. said it needed an exhaust pipe gasket and when it runs it kinda pops white smoke out of it, how concerned should I be about that? it looks like i can just undo a few screws and replace it (is it that easy?). Link to comment Share on other sites More sharing options...
Nysmanxs400 Posted October 10, 2011 Author Share Posted October 10, 2011 Also, I noticed I don't have a kick start is that normal? Link to comment Share on other sites More sharing options...
Moderator drewpy Posted October 10, 2011 Moderator Share Posted October 10, 2011 Also, I noticed I don't have a kick start is that normal? so you have a dohc bike then (maxim or seca) they don't have kick starters I thought kickstand was a kickstarter (we call them side stands) as for exhaust gaskets, easy enough to replace, its getting the old on out of its home. (use a pick) drewps Link to comment Share on other sites More sharing options...
Nysmanxs400 Posted October 11, 2011 Author Share Posted October 11, 2011 Drained the oil yesterday gonna put new oil in today and try not to over fill. My old oil smelled like gas, I'm guessing because the oil was getting into places it wasn't supposed to and should clear up. I'll fix that exhaust today I'm trying to take apart a little as possible, to avoid creating other problems. So, it's a DOHC? that'll help with picking a service manual. I didn't think it was odd at first with no kickstarter I'd only seen them on dirt bikes and ancient motorcycles, then i saw a 82 yamaha 750 with a kickstarter. It's not a big deal unless i keep killing my battery by having the lights on like i've done about 3 times now lol. Quick question, is it odd that my bike is easier to start cold at half choke than full? Thanks again for the advice. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted October 11, 2011 Moderator Share Posted October 11, 2011 a picture would help ID it along with 1st 4 digit frame number Link to comment Share on other sites More sharing options...
Nysmanxs400 Posted October 13, 2011 Author Share Posted October 13, 2011 @drewpy, do you mean the numbers on the engine? (12R005486) Drained the oil today then filled it back up ran it for a bit, no white smoke Link to comment Share on other sites More sharing options...
Moderator drewpy Posted October 13, 2011 Moderator Share Posted October 13, 2011 12r is dohc glad its sorted Link to comment Share on other sites More sharing options...
Nysmanxs400 Posted October 16, 2011 Author Share Posted October 16, 2011 So, went to start her up today and no problem starting even without choke (it was a pretty warm). She idled for a few min a little on the low rpm side around 1k or less so I opened the throttle and she cut off . . . odd. So, I started her a gain this time with choke, started no problem idled higher around 2k i eased off choke and rpms dropped, hit throttle and she cut off . . . odd. She hadn't done this before please tell me I'm just out of gas from having the reserve open the whole time (seriously i have lol) I'm hoping my little oil flooding hasn't damaged too much. Thanks in advance for the help. @drewpy, thanks for the help with the engine i printed out a service manual still looking for a owners manual for those pesky user questions like how to the petcock settings work Link to comment Share on other sites More sharing options...
Moderator drewpy Posted October 16, 2011 Moderator Share Posted October 16, 2011 probably needs to warm up, give it an Italian service. leave the pet cock on the on position as its vacuum operated and only flows petrol when the engine turns over! Link to comment Share on other sites More sharing options...
Nysmanxs400 Posted October 16, 2011 Author Share Posted October 16, 2011 Thanks, I'll try to let her warm up for a bit longer and i'll but some gas in for good measure today. I'm trying not to rider her too much since she's not street legal and missing the her front brake handles/cable. I turned petcock to reserve awhile ago then set it to pri for a bit when I looked up the correct setting for it turned it back to on. I feel like a noob (which i am) but what's an "Italian service"? Link to comment Share on other sites More sharing options...
Moderator drewpy Posted October 16, 2011 Moderator Share Posted October 16, 2011 Thanks, I'll try to let her warm up for a bit longer and i'll but some gas in for good measure today. I'm trying not to rider her too much since she's not street legal and missing the her front brake handles/cable. I turned petcock to reserve awhile ago then set it to pri for a bit when I looked up the correct setting for it turned it back to on. I feel like a noob (which i am) but what's an "Italian service"? ride it like you stole it! Link to comment Share on other sites More sharing options...
ArcheRD350 Posted December 28, 2011 Share Posted December 28, 2011 I had a similar problem with mine. Your carbs are over flowing into your head and filling up you crank case. In my case I found a crack in the right hand carb on the housing for the float valve. I epoxied it and replaced the float valve and needle. no problem since then. try replacing your float valve assy. clean carbs and inspect for small cracks. Link to comment Share on other sites More sharing options...
ArcheRD350 Posted January 28, 2012 Share Posted January 28, 2012 did you solve the carb problem? You bike looks like a Maxim 400 your's is off the line 2500 before mine. There are less and less of these bikes running. By 2015 there may not be but a few of the 20,000 there about that were made still on the streets. I am planning on repaintng mine. I will strip the whole thing down to the frame. I am wondering how to repaint the rims to match the original paint job. any suggestions on how to do that? Link to comment Share on other sites More sharing options...
yamily Posted February 20, 2012 Share Posted February 20, 2012 So, went to start her up today and no problem starting even without choke (it was a pretty warm). She idled for a few min a little on the low rpm side around 1k or less so I opened the throttle and she cut off . . . odd. So, I started her a gain this time with choke, started no problem idled higher around 2k i eased off choke and rpms dropped, hit throttle and she cut off . . . odd. She hadn't done this before please tell me I'm just out of gas from having the reserve open the whole time (seriously i have lol) I'm hoping my little oil flooding hasn't damaged too much. Thanks in advance for the help. @drewpy, thanks for the help with the engine i printed out a service manual still looking for a owners manual for those pesky user questions like how to the petcock settings work Hi Nysmansx400. I bought an 1980 xs400 a couple of months ago. It wasn't running when I got it, but after rebuilding the carbs and adjusting the valve clearance, it is at least running. But I've got the same problem: starts up and idles, but cuts out when throttle is applied. I'm guessing it is running to rich, but making adjustments to the pilot screw (aka air/fuel screw) has changed the problem, but not really solved it. Now it doesn't die, but will rev too high... If I make any more progress on getting this tuned, I'll let you know. Good luck! The service manual does offer many clues! Link to comment Share on other sites More sharing options...
Tommy xs Posted November 11, 2012 Share Posted November 11, 2012 I have had problem with 1984 dohc ,petrol leaking out of carbs into air box do i need new carbs? Link to comment Share on other sites More sharing options...
Moderator drewpy Posted November 11, 2012 Moderator Share Posted November 11, 2012 I have had problem with 1984 dohc ,petrol leaking out of carbs into air box do i need new carbs? no you need to check/renew the float valves, they should be smooth and flat with no ridges on them. Also the floats should not contain any fuel as that will let fuel over flow. Link to comment Share on other sites More sharing options...
Tommy xs Posted November 11, 2012 Share Posted November 11, 2012 thanks very much for that i'll give it a go next weekend and let you know how i get on Link to comment Share on other sites More sharing options...
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