k91 Posted March 8, 2008 Share Posted March 8, 2008 Sorry to make this my first post but I'm feeling pretty bummed right now. I bought a second XS400 about a week ago in the hopes that it was nearer to seeing the road than my current project XS. Well I guess I was wrong again. It started, it ran, it seemed to drive around at least when I brought it home. Well I spent the last week cleaning, adjusting, and fixing what I saw. Today I changed the oil and filter, cleaned the screen, replaced the plugs and cleaned and lubed the clutch. Well now it doesn't pull itself in any gear but I can hear and feel it shifting. It also seems to leak oil from the left cylinder right at the exhaust?? I did a compression check and found about 100 PSI in the right and 92 in the left. I guess its time to put it on ebay for parts Any hope? I did drive it around yesterday and a couple other times too. I'm thinking the carbs were sticking and filling the engine with gas so now the rings are toasted since the oil I drained seemed to be mostly gas. But what is up with the clutch? Link to comment Share on other sites More sharing options...
xs360 Posted March 9, 2008 Share Posted March 9, 2008 just wondered ... is it the original clutch cable , if so it would be 28 years old . and alternately has it been snagged in the headstock at some time ? Link to comment Share on other sites More sharing options...
k91 Posted March 9, 2008 Author Share Posted March 9, 2008 just wondered ... is it the original clutch cable , if so it would be 28 years old . and alternately has it been snagged in the headstock at some time ? It probably is the original. Now the mystery deepens again. Did another compression test this morning cold and it was 142 in left and 145 in right. So maybe I jumped the gun yesterday. I guess I'll have to do a leakdown now and see what happens. Maybe a valve is sticking when hot. And this was supposed to be a quickie project Link to comment Share on other sites More sharing options...
smgordon1259 Posted March 9, 2008 Share Posted March 9, 2008 Remember Murphys law. Don't rush to finish , do it right take your time. attack it at all angles. I have found in the many projects I have going that nothing is ever an easy fix.waiting for the weather to break so I can get started on my1982 xs400j. during the winter I have bought manuals repair and owners. cleaned and sanded the fenders and tank now they are ready to paint. now the task of wiring and trouble shooting the electrical system ( no spark issues.). I have learned more from reading the manuals and paying attention to message board forums . I need 1 more piece to complete the body work make that 2 going to dump the insect looking fairing and find a 7" headlamp and bucket and the upper battery cover . if all else fails i will just find a stock headlamp and include fogs. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted March 9, 2008 Moderator Share Posted March 9, 2008 It probably is the original. Now the mystery deepens again. Did another compression test this morning cold and it was 142 in left and 145 in right. So maybe I jumped the gun yesterday. I guess I'll have to do a leakdown now and see what happens. Maybe a valve is sticking when hot. And this was supposed to be a quickie project Or the piston rings have ungummed themselves!!! best way to maintain an engine is use it! Link to comment Share on other sites More sharing options...
k91 Posted March 10, 2008 Author Share Posted March 10, 2008 Or the piston rings have ungummed themselves!!! I doubt I could be so lucky. Any ideas on the oil out the exhaust? Oh and has anybody ordered from that http://www.partsnmore.com/ place? They seem to have the best price on airfilters I've seen. Also the XS650 carb holders are the same as the 400 aren't they? Mikesxs.com has a set for the BS34 carbs but they are a different yamaha part number between the 400 and 650 but they sure look the same. Any idea? Link to comment Share on other sites More sharing options...
yoda Posted March 10, 2008 Share Posted March 10, 2008 I think Drewpy is right about the rings. If the ring groves have gummed up or coked, then there could be a problem. Also if the rings line up which does happen, there will be a reduction of compression until they spin around again. Cannot fault the expression of running the engine to maintain it. Link to comment Share on other sites More sharing options...
XSwheels Posted March 10, 2008 Share Posted March 10, 2008 When I picked up my XS360 project it had 95psi in the left cylinder. I poured one ounce of ATF/acetone concoction into the cylinder twice over 2 days. I ran the engine a few seconds and after it cooled had 115 psi. I expect that will improve later on when I can run the engine more. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted March 10, 2008 Moderator Share Posted March 10, 2008 I doubt I could be so lucky. Any ideas on the oil out the exhaust? Oh and has anybody ordered from that http://www.partsnmore.com/ place? They seem to have the best price on airfilters I've seen. Also the XS650 carb holders are the same as the 400 aren't they? Mikesxs.com has a set for the BS34 carbs but they are a different yamaha part number between the 400 and 650 but they sure look the same. Any idea? I've used that company once, and can't fault them, even sending to UK not sure about the carb holders, its the connection to the engine which you need to look at. oil in exhaust, bit of blow back from the gummed up piston rings? which if now ungummed could be ok now! also your valve seal could have hardened and letting oil by pass the seal. Link to comment Share on other sites More sharing options...
k91 Posted March 11, 2008 Author Share Posted March 11, 2008 Thanks for your help guys Whats everybody running for oil as far as weight and brand? I bought some new carb holders last night so hopefully that cures my surging and racing at idle but if not its time to blow apart the carbs again. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted March 11, 2008 Moderator Share Posted March 11, 2008 Thanks for your help guys Whats everybody running for oil as far as weight and brand? I bought some new carb holders last night so hopefully that cures my surging and racing at idle but if not its time to blow apart the carbs again. I use Millars 20w 50 sports semi-synth. its expensive as it is blended on a small scale. being meant for older engines it works fine with Clutch in oil systems. I have used 10w 40 but found it too thin and tends to get a bit hot. Link to comment Share on other sites More sharing options...
xs360 Posted March 11, 2008 Share Posted March 11, 2008 also ready with the millers 20w50 for the next oil change !! Link to comment Share on other sites More sharing options...
Cy Welch Posted March 11, 2008 Share Posted March 11, 2008 Thanks for your help guys Whats everybody running for oil as far as weight and brand? I bought some new carb holders last night so hopefully that cures my surging and racing at idle but if not its time to blow apart the carbs again. I wouldn't get your hopes up. Get the BS34 carb kits from MikesXS as every carb I have seen for the 1980 has had the o-rings for the carb needle valves worn to the point that they leak gas around them. Also remember these bikes were tuned LEAN for 1980 gas, so with the addition of 10-20% alcohol in the U.S. they are REALLY lean. MikesXS has a kit to replace the idle mix screws which includes the plugs that are needed over them so you can adjust the mix for good idle. I haven't done this yet, but plan on doing it in the next month or so. I also have found that mine at least runs far better on 91 octane as the manual says it needs. If I put that 87 octane crap in it I have trouble with starting and idling just for starters. I don't know what type of gas they have across the pond, but I suspect it's better than the crap they sell us here. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted March 12, 2008 Moderator Share Posted March 12, 2008 I wouldn't get your hopes up. Get the BS34 carb kits from MikesXS as every carb I have seen for the 1980 has had the o-rings for the carb needle valves worn to the point that they leak gas around them. Also remember these bikes were tuned LEAN for 1980 gas, so with the addition of 10-20% alcohol in the U.S. they are REALLY lean. MikesXS has a kit to replace the idle mix screws which includes the plugs that are needed over them so you can adjust the mix for good idle. I haven't done this yet, but plan on doing it in the next month or so. I also have found that mine at least runs far better on 91 octane as the manual says it needs. If I put that 87 octane crap in it I have trouble with starting and idling just for starters. I don't know what type of gas they have across the pond, but I suspect it's better than the crap they sell us here. yea we have good fuel over here, but then we pay dearly for it!!! £1.12 a litre Link to comment Share on other sites More sharing options...
k91 Posted March 12, 2008 Author Share Posted March 12, 2008 I usually run at least 89 octane in my bikes since that has additives in it unlike the junk 87. I guess I'll order carb kits too since my old bowl gaskets are a little leaky anyways. Here's a pic of the beast when I brought it home if anybody is interested. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted March 12, 2008 Moderator Share Posted March 12, 2008 I usually run at least 89 octane in my bikes since that has additives in it unlike the junk 87. I guess I'll order carb kits too since my old bowl gaskets are a little leaky anyways. Here's a pic of the beast when I brought it home if anybody is interested. make a nice cafe racer that would!! Like this one? if anyone knows who's this is i'd like to know Link to comment Share on other sites More sharing options...
yoda Posted March 12, 2008 Share Posted March 12, 2008 I've used that company once, and can't fault them, even sending to UK not sure about the carb holders, its the connection to the engine which you need to look at. oil in exhaust, bit of blow back from the gummed up piston rings? which if now ungummed could be ok now! also your valve seal could have hardened and letting oil by pass the seal. The crankcase breathers need to be checked as well. If these are at all blocked, you will get the same result. Link to comment Share on other sites More sharing options...
bralkan Posted March 12, 2008 Share Posted March 12, 2008 make a nice cafe racer that would!! Like this one? if anyone knows who's this is i'd like to know Drewpy, have you seen these? There are some XS on there.... Some cool looking stuff, for sure. http://www.bratstyle.com/custom/custom.htm I wish I could figure out what they do with the battery. http://www.bratstyle.com/custom/sr400%20br...400%20brat2.htm http://www.bratstyle.com/custom/xs650%20mi...650%20miura.htm http://www.bratstyle.com/custom/81%20xs650...50%20hikita.htm http://www.bratstyle.com/custom/45/45.htm Might be my favorite: http://www.bratstyle.com/custom/56/56.htm Once I get my bike running (should rebuild the top end this weekend and finally be done with it.....Oh ya, I have to fix my flashers... ugh), I'd like to try and get it to look like: http://www.bratstyle.com/photo%20709.jpg Link to comment Share on other sites More sharing options...
Moderator drewpy Posted March 12, 2008 Moderator Share Posted March 12, 2008 Drewpy, have you seen these? Once I get my bike running (should rebuild the top end this weekend and finally be done with it.....Oh ya, I have to fix my flashers... ugh), I'd like to try and get it to look like: http://www.bratstyle.com/photo%20709.jpg then you will have to call yourself "bratkan" then!! they do look cool, the way I am going to get that "see through" look is to find a tiny battery to fit where the starter motor is and I also have a reg/rec in 1 unit to put under the tank. I also have a BMW remote master brake cyl which I'm going to mount under the tank and have alloy coils al fresco A la Triumph. this will give me the bare look i want on the handle bars ( the hornbutton will fit like a bar end) no lights, just brake light for MOT Link to comment Share on other sites More sharing options...
bralkan Posted March 12, 2008 Share Posted March 12, 2008 then you will have to call yourself "bratkan" then!! they do look cool, the way I am going to get that "see through" look is to find a tiny battery to fit where the starter motor is and I also have a reg/rec in 1 unit to put under the tank. I also have a BMW remote master brake cyl which I'm going to mount under the tank and have alloy coils al fresco A la Triumph. this will give me the bare look i want on the handle bars ( the hornbutton will fit like a bar end) no lights, just brake light for MOT I was thinking about putting it in the starter as well (since mine doesn't work - btw, I had hooked it straight to a battery and it made some noise, sounded like it tried to move a bit and then it stopped).... Have you seen any 12v batts that are small enough to fit in there? Link to comment Share on other sites More sharing options...
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