peterb1951 Posted June 19, 2012 Posted June 19, 2012 Sorry Guys, I know this is probably old ground but any help would be appreciated, my 1989 XJ600 needed new carb mounting rubbers so I bit the bullet and bought a set, I also invested in a set of balance gauges, fitted new rubbers OK but when it came to balancing I had problems, firstly I wrongly identified the master carb, secondly I did it all wrong, having then read the manual after finding it! I had another go, but its still not right firstly the throttle takes its time to come down and as the machine gets warm the idle gets higher, the gauges all seem to be about the same and it is better than the first attempt although still not correct but when I was trying to set them up the engine temp was getting higher this seemed to make for all sort of problems Are you supposed to do the balance on tickover? can you start from scratch again? Peter Bainbridge
blackhat250 Posted June 19, 2012 Posted June 19, 2012 Hi peter. you say engine temp is getting hot, sound like your running lean, are you adjusting idle screws to balance , or mistakingly the mixture, check diagram for correct screws,, and are the new rubbers tight,[ air leak]
Moderator Airhead Posted June 19, 2012 Moderator Posted June 19, 2012 just a thought I did mine on my bandit last weekend, speed is of the essence because essentially the bike is air cooled and with an idle speed set to 1750 it gets hot quickly
peterb1951 Posted June 19, 2012 Author Posted June 19, 2012 Hi peter. you say engine temp is getting hot, sound like your running lean, are you adjusting idle screws to balance , or mistakingly the mixture, check diagram for correct screws,, and are the new rubbers tight,[ air leak] Definitely the correct screws there are three, the correct way or as I understand it is adjust left screw to match carbs 1 and 2, then adjust right screw to match carbs 3 and 4 then the centre screw is used to match the 2 pairs together, and as far as I can tell the rubbers are sealed with new gaskets fitted, no mention in manual as to what rpm you run at and the only way that I can adjust tickover is by using the length adjuster to the cable outer, Peter
peterb1951 Posted June 19, 2012 Author Posted June 19, 2012 just a thought I did mine on my bandit last weekend, speed is of the essence because essentially the bike is air cooled and with an idle speed set to 1750 it gets hot quickly Well I must say Dont think I was that quick, and believe at one point it cut out and would not start ,think engine was too hot as it started fine after leaving it for a while, Peter
Moderator drewpy Posted June 20, 2012 Moderator Posted June 20, 2012 keep practicing, it takes a while. So long as the the readings are the same on each carb, it doesn't matter what they are saying. Did you rig up a temporary fuel supply?
peterb1951 Posted June 21, 2012 Author Posted June 21, 2012 keep practicing, it takes a while. So long as the the readings are the same on each carb, it doesn't matter what they are saying. Did you rig up a temporary fuel supply? I did, but I think I maybe taking too long so engine and carbs getting too hot with possible fuel vaporization occuring
2 Wheels Posted June 21, 2012 Posted June 21, 2012 I did, but I think I maybe taking too long so engine and carbs getting too hot with possible fuel vaporization occuring It is important to be quite quick,,,, that said you can balance carbs 1 and 2 then shut engine off,,,,, then restart and balance carbs 3 and 4,,,, shut engine off again and let it rest,,,,,, this method will not be accurate but it will get them closer to where they should be. Then you can start again and do the whole thing in one go + balance carbs left and right to eachother. If the idle speed of the bike is say 1150 then you should try and balance carbs at an idle speed of arround 1500, this will give you enough movement downwards without the bike stalling. When all is ballanced adjust idle back down to what it should be. Are you sure there is no screw to adjust tickover without using the cable adjuster ?? I think there should be one !
peterb1951 Posted June 21, 2012 Author Posted June 21, 2012 It is important to be quite quick,,,, that said you can balance carbs 1 and 2 then shut engine off,,,,, then restart and balance carbs 3 and 4,,,, shut engine off again and let it rest,,,,,, this method will not be accurate but it will get them closer to where they should be. Then you can start again and do the whole thing in one go + balance carbs left and right to eachother. If the idle speed of the bike is say 1150 then you should try and balance carbs at an idle speed of arround 1500, this will give you enough movement downwards without the bike stalling. When all is ballanced adjust idle back down to what it should be. Are you sure there is no screw to adjust tickover without using the cable adjuster ?? I think there should be one ! I think you are correct about the tickover screw as I have seen mentioned but have yet to find it myself, but I will try your method next time I do it as it sound good to me, cheers mate
dt502001 Posted June 22, 2012 Posted June 22, 2012 The idle adjuster is a cable mounted to the bottom of the left carb if I remember correctly ( check with your dealer) and push up on the throttle plate,that would cause you to have trouble setting the ballance if the only way you can adjust the idle( tick over) is to adj the throttle cable, as the carbs come to ballance the idle will go up and need to be adjusted down. Borrow all your mate's house fans for a few hours and that will help with the heat problem
peterb1951 Posted June 24, 2012 Author Posted June 24, 2012 The idle adjuster is a cable mounted to the bottom of the left carb if I remember correctly ( check with your dealer) and push up on the throttle plate,that would cause you to have trouble setting the ballance if the only way you can adjust the idle( tick over) is to adj the throttle cable, as the carbs come to ballance the idle will go up and need to be adjusted down. Borrow all your mate's house fans for a few hours and that will help with the heat problem I have a couple of fans and may give that a try, as to tick over it makes sense that the rpm will go up as the carbs balance out, so I am going to take everyone's advice and have another go cheers
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