Kawasaki GT550 Carbs
- Thread starter hecklejk
- Start date
teazer said:
Bike runs exellent over 3000rpm, but at tick over and below 3000rpm the bike will not stay running. The mechanic had a look and found some parts missing from the carbs and replaced them with new parts. Fired the bike back up and couldnt get the bike to idle properly on tick over. He said that the carbs are worn out and need to be replaced... vacume carbs, so all greek to me....
Sounds to me like the carbs need a good clean out of all those tiny passageways. Your mechanic hasn't got the time to mess with that, but you may. Carbs are not as complicated as people think. They do need a firm but gentle, methodical approach though.
It is still possible that the butterfly shafts are worn out and leaking air at low speed, but that usually takes a truck load of miles and abuse. Try to grab the end of a shaft or where the cables attach and see if teh shafts are loose in the carb bodies. There should be little or no discernible play there.
If that's OK, pull the carbs and strip and clean then. Keep good notes and take lots of pictures as you go. Have 4 small baking trays to put the parts in and lable them 1,2 etc so the bits go back into their correct carb.
It is still possible that the butterfly shafts are worn out and leaking air at low speed, but that usually takes a truck load of miles and abuse. Try to grab the end of a shaft or where the cables attach and see if teh shafts are loose in the carb bodies. There should be little or no discernible play there.
If that's OK, pull the carbs and strip and clean then. Keep good notes and take lots of pictures as you go. Have 4 small baking trays to put the parts in and lable them 1,2 etc so the bits go back into their correct carb.
teazer said:
That is exactly the issue... the butterfly shafts are worn out.. bike has 65k on the clock.. used to be a dispatch bike in London... found this out AFTER I bought it from a bloke in Derby.... I do trust the mechanic that told me the state of the carbs, as he told me this might be the problem BEFORE he looked at the bike...
Ah so. That would be a problem. If you can find a set of carbs at the right price, that would be ideal, but if not, they can probably be bushed but you'd have to find someone good and cheap. Miki\uni BS (CV) carbs typically used to have brass bushes but later carbs may have dispensed with that luxury and I have no idea how Keihin made theirs. If there's enough meat in the carbs, they could be bored 2mm O/S and have a 1mm wall thickness bushes inserted.
Any machinist should be able to machine a batch of 8 or ten (to be safe) bushes and bore the bodies. He should also be able to make a tool like a valve guide removal tool to press the bushes in.
Other possibilities might be from a later KZ550 or maybe a 650 if they have similar spacing. Or a 550 Zephyr perchance.
Any machinist should be able to machine a batch of 8 or ten (to be safe) bushes and bore the bodies. He should also be able to make a tool like a valve guide removal tool to press the bushes in.
Other possibilities might be from a later KZ550 or maybe a 650 if they have similar spacing. Or a 550 Zephyr perchance.
