killahurtz Posted May 29, 2009 Share Posted May 29, 2009 Hi All, I am working on an 82 XJ 650 and having an issue I cant seem to figure out. Before I start tearing things apart I thought to check here. The #1 cylinder is dead. The bike will only run when choked and is very rough. If you pull the plug caps off while running they all have an effect on the idle except #1. Also gas is spewing from the exhaust on that side of the engine, lots of it. So far what I have done: Changed plugs -- no change Checked compression -- fine Checked for spark on #1 wire and plug -- it has it The bike has only 8500 miles on it and is in other wise very good shape and seems to be well maintained, only ridden by a woman. Could it be the valves need adjusting, or maybe the #1 carb is flooding it? Thanks! Link to comment Share on other sites More sharing options...
JimR Posted May 30, 2009 Share Posted May 30, 2009 Hi All, I am working on an 82 XJ 650 and having an issue I cant seem to figure out. Before I start tearing things apart I thought to check here. The #1 cylinder is dead. The bike will only run when choked and is very rough. If you pull the plug caps off while running they all have an effect on the idle except #1. Also gas is spewing from the exhaust on that side of the engine, lots of it. So far what I have done: Changed plugs -- no change Checked compression -- fine Checked for spark on #1 wire and plug -- it has it The bike has only 8500 miles on it and is in other wise very good shape and seems to be well maintained, only ridden by a woman. Could it be the valves need adjusting, or maybe the #1 carb is flooding it? Thanks! Hi, if you have good compression on cyl#1 there will be no need realy to check the valves ... but where all 4 within about 1% of each other or was cyl #1 a little different ? if all was ok here you may need to look at the floats etc to ensure that carb #1 is not just (as you say) just supplying to much fuel. You can discount the ignition circut as if this was down cyl #3 would also act up ... Just an odd point does the bike have a YICS cylinder head ? Regards Jim Link to comment Share on other sites More sharing options...
killahurtz Posted May 30, 2009 Author Share Posted May 30, 2009 Hi, if you have good compression on cyl#1 there will be no need realy to check the valves ... but where all 4 within about 1% of each other or was cyl #1 a little different ? if all was ok here you may need to look at the floats etc to ensure that carb #1 is not just (as you say) just supplying to much fuel. You can discount the ignition circut as if this was down cyl #3 would also act up ... Just an odd point does the bike have a YICS cylinder head ? Regards Jim Hi Jim, Yes the bike has a YICS head. I found a service manual online and was reading through that. You say to discount the ignition because cyl #3 would be acting up.... I thought the service manual said that #1 and #4 fire at the same time and #2 and #3. I could have not been reading that right. So far I only tested compression on #1 and #2, as they are right next to each other and was easy, they were very close. I will test the rest after I go pickup the bike. Thanks! Link to comment Share on other sites More sharing options...
JimR Posted May 30, 2009 Share Posted May 30, 2009 Hi Jim, Yes the bike has a YICS head. I found a service manual online and was reading through that. You say to discount the ignition because cyl #3 would be acting up.... I thought the service manual said that #1 and #4 fire at the same time and #2 and #3. I could have not been reading that right. So far I only tested compression on #1 and #2, as they are right next to each other and was easy, they were very close. I will test the rest after I go pickup the bike. Thanks! Hi Sorry ment cyl #4 .... typo ! As the bike has a YICS head there is a chance that the carbs are so far out of balance (if someone has tried to balance them with not using the tool). The YICS chamber will not give correct readings to the vaccum guages unless it is shut off with the correct tool. if #1 & #2 have simular readings I would guess #3 & #4 will be simular but what reading did you get ? Regards Jim Link to comment Share on other sites More sharing options...
WizZ Posted June 3, 2009 Share Posted June 3, 2009 I would look at float valve not shutting off on #1, also possible petcock malfunction. When using the YICS tool to sync' the carbs, make sure the YICS ports are clear, otherwise there is no point in using the tool. I take it you have a strong spark on #1. Link to comment Share on other sites More sharing options...
JimR Posted June 3, 2009 Share Posted June 3, 2009 I would look at float valve not shutting off on #1, also possible petcock malfunction. When using the YICS tool to sync' the carbs, make sure the YICS ports are clear, otherwise there is no point in using the tool. I take it you have a strong spark on #1. What does this mean ? with the Swill/yics ports blocked the carbs will sync without the tool as the tool just blocks the ports off. As the fuel is supplied to all carbs via the same petcock (railed) if you had a petcock malfunction it would apply to all cylinders ? or did you mean the needle valve for cyl #1 ? which may give an over rich/flood from that carb if faulty. The Spark to #1 will be the same as the supplied to its shared cylinder (I always get it wrong number wise) but if the other cylinder is running ok I would discount the spark. Regards Jim Link to comment Share on other sites More sharing options...
WizZ Posted June 3, 2009 Share Posted June 3, 2009 What does this mean ? with the Swill/yics ports blocked the carbs will sync without the tool as the tool just blocks the ports off. As the fuel is supplied to all carbs via the same petcock (railed) if you had a petcock malfunction it would apply to all cylinders ? or did you mean the needle valve for cyl #1 ? which may give an over rich/flood from that carb if faulty. The Spark to #1 will be the same as the supplied to its shared cylinder (I always get it wrong number wise) but if the other cylinder is running ok I would discount the spark. Regards Jim Although the spark is shared, there can still be a breakdown of HT lead, cap or plug. If the YICS ports are blocked, & they are small on the 650s, you might as well sync' without the tool, is all I am saying. The fuel rail is fed between 1 & 2 so would exaserbate any potential problem with float# 1. Link to comment Share on other sites More sharing options...
JimR Posted June 3, 2009 Share Posted June 3, 2009 Although the spark is shared, there can still be a breakdown of HT lead, cap or plug. If the YICS ports are blocked, & they are small on the 650s, you might as well sync' without the tool, is all I am saying. The fuel rail is fed between 1 & 2 so would exaserbate any potential problem with float# 1. How many times has the ht coil failed on that model (in the UK) = near 0 ht cap is a thought but as long as they show some resistance (stop the tellys playing up) they should work. With a dual lead coil if one ht lead goes OC the whole coil goes down ... from memory the fuel rail was supplied between 2 & 3 (in the UK) but I guess in other parts of the world that may differ. I guess that you discount the needle valve to at all be at fault with cyl #1. With age the Yics port could 'gunk' up but I would guess this to happen if the bike was laid up for quite some time and you couldn't confirm all 4 ports are blocked so therefore the sync between 1 & 2 may be flawed (thro a blocked port) then the rest give a totally wrong reading because the correct tool is not used in accordance with its designers ! Regards Jim Link to comment Share on other sites More sharing options...
killahurtz Posted June 10, 2009 Author Share Posted June 10, 2009 Well I just got the bike here the other day where I could get into it, been crazy around here. First things first, drained the oil because it was over full, I think half of what I drained was pure gas mixed with the oil, had way more than 2.5 qts in it. Being that one cyl wasn't firing for longer than maybe they thought i guess that much could have washed down or maybe the oil has not been changed in forever, who knows, but it smelled badly of gas. With new oil in, I retested the compression and am getting 120 psi +-4 in each cyl. I switched the #1 and #4 HT wires out and sure enough #1 would fire and #4 would not. I will note that I tested the #1 cable with the spark plug in and grounded on the head and it was sparking, however not as strong as I would have liked. I trimmed a .5 inch off of the HT cable where the boot screws onto and re-attached it. That seemed to help some, as I could get it to idle without choke and I even rode it (not far). Ride report: Thing is ROUGH running!!! I am not a bike mechanic, my experience comes from heavy equipment, however I have owned bikes in the past and present. This thing should be as smooth as silk for an I-4. It rides like my V-twin SV650 when you get water in the front cyl plug well in the rain. So my diagnosis is that this thing needs the carbs gone through and a valve adjustment first and foremost. Maybe also a new coil pack and wires for #1 and #4. Anyone have other ideas? So is there any way I can balance the carbs without this special YICS tool? Can I make one of my own easily? Link to comment Share on other sites More sharing options...
Cy Welch Posted June 11, 2009 Share Posted June 11, 2009 Ride report: Thing is ROUGH running!!! I am not a bike mechanic, my experience comes from heavy equipment, however I have owned bikes in the past and present. This thing should be as smooth as silk for an I-4. It rides like my V-twin SV650 when you get water in the front cyl plug well in the rain. So my diagnosis is that this thing needs the carbs gone through and a valve adjustment first and foremost. Maybe also a new coil pack and wires for #1 and #4. Anyone have other ideas? So is there any way I can balance the carbs without this special YICS tool? Can I make one of my own easily? Sounds a lot like carb troubles. The YICS tool is pretty much mandatory for a proper and working sync. IIRC on xs11.com there is a guy that sells or has plans for a third party YICS tool that I believe works with the 650's. Link to comment Share on other sites More sharing options...
JimR Posted June 11, 2009 Share Posted June 11, 2009 Well I just got the bike here the other day where I could get into it, been crazy around here. First things first, drained the oil because it was over full, I think half of what I drained was pure gas mixed with the oil, had way more than 2.5 qts in it. Being that one cyl wasn't firing for longer than maybe they thought i guess that much could have washed down or maybe the oil has not been changed in forever, who knows, but it smelled badly of gas. With new oil in, I retested the compression and am getting 120 psi +-4 in each cyl. I switched the #1 and #4 HT wires out and sure enough #1 would fire and #4 would not. I will note that I tested the #1 cable with the spark plug in and grounded on the head and it was sparking, however not as strong as I would have liked. I trimmed a .5 inch off of the HT cable where the boot screws onto and re-attached it. That seemed to help some, as I could get it to idle without choke and I even rode it (not far). Ride report: Thing is ROUGH running!!! I am not a bike mechanic, my experience comes from heavy equipment, however I have owned bikes in the past and present. This thing should be as smooth as silk for an I-4. It rides like my V-twin SV650 when you get water in the front cyl plug well in the rain. So my diagnosis is that this thing needs the carbs gone through and a valve adjustment first and foremost. Maybe also a new coil pack and wires for #1 and #4. Anyone have other ideas? So is there any way I can balance the carbs without this special YICS tool? Can I make one of my own easily? Hi, if the YICS ports are blocked thats just the right position to balance & check the mixture on the carbs ... but if the YICS ports are not blocked you would need the Tool of which I have the diagrams to make one which will cost about £20~£30 to do (or you can find a ready made one on ebay perhaps). There is also a post on the forum which gives you the Yamaha part no so you could buy a 'real one' Regards Jim Link to comment Share on other sites More sharing options...
Cy Welch Posted June 11, 2009 Share Posted June 11, 2009 Hi, if the YICS ports are blocked thats just the right position to balance & check the mixture on the carbs ... but if the YICS ports are not blocked you would need the Tool of which I have the diagrams to make one which will cost about £20~£30 to do (or you can find a ready made one on ebay perhaps). There is also a post on the forum which gives you the Yamaha part no so you could buy a 'real one' Regards Jim Additionally the plans I have seen for one are for a permanent one that is left in place unlike the yamaha one. YICS is an emision deal that balances out slight imbalances in syncing of the carbs, with properly balanced carbs it does nothing, and with a balancing problem it just hides it. Link to comment Share on other sites More sharing options...
killahurtz Posted June 11, 2009 Author Share Posted June 11, 2009 Additionally the plans I have seen for one are for a permanent one that is left in place unlike the yamaha one. YICS is an emision deal that balances out slight imbalances in syncing of the carbs, with properly balanced carbs it does nothing, and with a balancing problem it just hides it. So you are saying the YICS ports are useless of the carbs are balanced... Could I/should I disable the ports? I assume when you say permanent you are talking about disabling them.?.? On a side note, I want to thank you guys for the valuable input. Often on some forums people are not so nice to new members with questions such as mine. Thanks! I will do the carbs next week and report back! Link to comment Share on other sites More sharing options...
fishandspud Posted August 22, 2010 Share Posted August 22, 2010 If you are still having problems you could try balancing the carbs with the YICS shut off tool, try this link http://cgi.ebay.co.u...=STRK:MESELX:IT Link to comment Share on other sites More sharing options...
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