Untold Posted March 22, 2011 Share Posted March 22, 2011 Hi All! First I just wanted to announce to the world that I got my '89 XJ600 back on the road after 10 years storage in someone's garage I just got it MOT'd and rode it a couple of times today. Bike feels good, balanced and comfy. It handles better than I'd expected. There seems to be plenty of power (gears seem very close together..), throttle response is ok, it just sounds a bit rough, a bit lumpy. I cleaned the carbs using solvent and cleared all the passages, especially the jets, but there could be a bit of residue still in there. It is possible the ignition is not at its best either (old HT leads and plugs, though I gapped them). The question is, do you think it will improve after a few good runs? (using redex to try and help the carbs) Or could there be something fundamentally wrong that I've missed? Idle is a bit uneven, but I'd expect that. Two of the air screws are not adjustable, they are totally seized and I've damaged the screw heads in my frustration, but due to the size of the venturi compared to those screws, they can't have an affect above idle speed can they? If all is well I'll commute on it tomorrow, thats a 30 mile round trip. I'm a little nervous because today was my first day on a bike since an accident about 5 years ago!! All ideas welcome. Link to comment Share on other sites More sharing options...
barkwindjammer Posted March 22, 2011 Share Posted March 22, 2011 Sounds like carbs are out of balance-you need to get them air screws sorted and get it balanced on all 4 , also have a feel at the downpipes from a cold start-are they all hotting up ? Link to comment Share on other sites More sharing options...
Untold Posted March 22, 2011 Author Share Posted March 22, 2011 Sounds like carbs are out of balance-you need to get them air screws sorted and get it balanced on all 4 , also have a feel at the downpipes from a cold start-are they all hotting up ? Hmm. Balancing them is going to be tricky, unless I can match cylinders 3 and 4 to 1 and 2? (the screws on 3 and 4 are fine (counting cylinders from left to right of bike)). I might need to source some parts on ebay as those screws are well and truly stuck, I tried soaking them in WD40 every day for a week and it had no effect. Carb cleaner likewise. Will try and remember to check how the downpipes heat up tomorrow morning - good idea. Link to comment Share on other sites More sharing options...
Untold Posted March 22, 2011 Author Share Posted March 22, 2011 Ah, just looked up how to balance carbs. Looks like you don't have to touch the air screws, its all about manifold vacuum and adjustment of the throttle links to the butterfly valves to make it the same everywhere. Sorry to state the obvious to everyone, I feel like I'm the only one who doesn't know this sort of thing, but this is great because there is now a chance of sorting it out. There seem to be a few balancers on ebay. Any recommendations? Link to comment Share on other sites More sharing options...
Untold Posted March 24, 2011 Author Share Posted March 24, 2011 Sounds like carbs are out of balance-you need to get them air screws sorted and get it balanced on all 4 , also have a feel at the downpipes from a cold start-are they all hotting up ? Barkwindjammer, you were right about the carbs, they are totally out of whack! Felt the downpipes while warming up. They all warmed up at different rates except number 1 which didn't seem to heat up at all! It was hot after I rode to work, so I have to assume ignition is ok in that one and its a carb problem. Still. Thanks for your help, its such an easy way to spot a problem and I would not have thought of it. Now whether to get my own vacuum gauge or get a pro to do it? And in an unrelated issue, when I arrived at work the headlight and taillight weren't working a few teething problems to sort out still! I expect a plug got dislodged somewhere, or maybe the bulbs gave up after so long in storage, but together? Link to comment Share on other sites More sharing options...
barkwindjammer Posted March 24, 2011 Share Posted March 24, 2011 Ok so cylinder number 1 isn't firing-could be the plug?,try taking the plug out of 1 and 4 (cos their easy to get at) and swap them over and see what happens from a cold start check the fuse box for a blown fuse for the lighting circuit next at some stage have a wander round some garage/lock-up sites and listen for tapping sounds or engine revving noises - this will indicate the distinct tinkering behaviour of an 'oily jumper guy', introduce yourself thus "wow", "do you balance your own carbs"? Link to comment Share on other sites More sharing options...
Untold Posted March 24, 2011 Author Share Posted March 24, 2011 Ok so cylinder number 1 isn't firing-could be the plug?,try taking the plug out of 1 and 4 (cos their easy to get at) and swap them over and see what happens from a cold start check the fuse box for a blown fuse for the lighting circuit next at some stage have a wander round some garage/lock-up sites and listen for tapping sounds or engine revving noises - this will indicate the distinct tinkering behaviour of an 'oily jumper guy', introduce yourself thus "wow", "do you balance your own carbs"? Thanks for the reply. Will try swapping the plugs, but all the pipes were equally toasty after a ride. Certainly sensible to eliminate the ignition from the list of potential problems tho. Like your suggestion for balancing will have to locate some lock-ups.. The local bike man quoted me £50-£60 to sort it, but I could get a set of four cheapo gauges from ebay, delivered for £35 so I'm tempted to learn the tricks myself. As for lighting, the fuses appear to be fine... I have no headlight, full beam or dipped, no parking light and no tail light. Passing flash switch does nothing either, but the brake light is fine for front and back brakes. Very limited visual check on wiring (under tank only) did not reveal any problems. Wondering if some relay module could have gone? Trying to find a wiring diagram... Link to comment Share on other sites More sharing options...
barkwindjammer Posted March 24, 2011 Share Posted March 24, 2011 They will all be hot after a ride cos heat travels, maybe Wild Foamy could help you with a 'wiry diagram', and £50 doesn't sound too bad for carb balance, the £35 guages will hang in your garage and get rusty-unless you plan a long career of buying and sorting up 4 strokes I personally wouldn,t bother-butt its your money Link to comment Share on other sites More sharing options...
KidValentino Posted March 24, 2011 Share Posted March 24, 2011 Thanks for the reply. Will try swapping the plugs, but all the pipes were equally toasty after a ride. Certainly sensible to eliminate the ignition from the list of potential problems tho. Like your suggestion for balancing will have to locate some lock-ups.. The local bike man quoted me £50-£60 to sort it, but I could get a set of four cheapo gauges from ebay, delivered for £35 so I'm tempted to learn the tricks myself. As for lighting, the fuses appear to be fine... I have no headlight, full beam or dipped, no parking light and no tail light. Passing flash switch does nothing either, but the brake light is fine for front and back brakes. Very limited visual check on wiring (under tank only) did not reveal any problems. Wondering if some relay module could have gone? Trying to find a wiring diagram... Try pulling apart the connectors and firing in some wd40 this has worked for me on my FZ600 project, the lights parking or tail didnt work but after a bit of cleaning they are great now. Cheers Kieran Link to comment Share on other sites More sharing options...
Untold Posted March 25, 2011 Author Share Posted March 25, 2011 Try pulling apart the connectors and firing in some wd40 this has worked for me on my FZ600 project, the lights parking or tail didnt work but after a bit of cleaning they are great now. Cheers Kieran Thanks Kieran. Its good to hear that someone else had a similar problem and fixed it so easily! My bike passed its MOT only a week or so ago and the lights were all fine on Wednesday, so I am hoping its just a loose connection. I'll give all the plugs a good clean this weekend and WD40 them. Link to comment Share on other sites More sharing options...
Untold Posted March 26, 2011 Author Share Posted March 26, 2011 Well, I swapped over the plugs and got the same result. Cylinder 1 takes ages to heat up, but I shut off the choke and continued warming it up. The number 1 downpipe slowly warmed (much more quickly than the head) so I know there is ignition there. I suspected the idle jet in cylinder one might have been clogged. It was seized in the carb when I first tried to clean it so I could not guarantee it was as clean as the others. I went and bought a better screwdriver, took the carbs off, got it out (finally) and cleaned it thoroughly. There seems to be an improvement in smoothness, but its not quite there. I oiled the carb pistons which helped the throttle response, it doesn't feel "lumpy" now, just not exactly smooth. I think the carbs still need balancing. I have heard from a couple of (older) fettlers about using a tube and your ear to synch carbs. I might try that as I have nothing to lose really. Though I doubt it will be easy on the Mikunis because of the bypass that handles airflow at idle... (where do you put the tube?) Will take it for a ride later and see if it performs better on the road now too. As for the lights, after cleaning every connector and spending ages trying to trace the fault, I found that if I tapped the fuse box, the lights came on will have to check all the wires and connections to/in the box and fix whatever is loose! Nice not to have to spend any more money on it though Link to comment Share on other sites More sharing options...
barkwindjammer Posted March 26, 2011 Share Posted March 26, 2011 Well, I swapped over the plugs and got the same result. Cylinder 1 takes ages to heat up, but I shut off the choke and continued warming it up. The number 1 downpipe slowly warmed (much more quickly than the head) so I know there is ignition there. I suspected the idle jet in cylinder one might have been clogged. It was seized in the carb when I first tried to clean it so I could not guarantee it was as clean as the others. I went and bought a better screwdriver, took the carbs off, got it out (finally) and cleaned it thoroughly. There seems to be an improvement in smoothness, but its not quite there. I oiled the carb pistons which helped the throttle response, it doesn't feel "lumpy" now, just not exactly smooth. I think the carbs still need balancing. I have heard from a couple of (older) fettlers about using a tube and your ear to synch carbs. I might try that as I have nothing to lose really. Though I doubt it will be easy on the Mikunis because of the bypass that handles airflow at idle... (where do you put the tube?) Will take it for a ride later and see if it performs better on the road now too. As for the lights, after cleaning every connector and spending ages trying to trace the fault, I found that if I tapped the fuse box, the lights came on will have to check all the wires and connections to/in the box and fix whatever is loose! Nice not to have to spend any more money on it though you put one end in your ear, and the other end in your other ear-and unbelievably-you can hear the sea shore even though its 68 miles away Link to comment Share on other sites More sharing options...
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