Paulwhite Posted March 9, 2011 Share Posted March 9, 2011 hi m8 , we didn't touch tappets when service was done... so don't think thats the problem, diaphrams are ok and put fresh fuel as well... that's why i don't know what else to do next! you said that the plugs are comming out black which would mean a fueling/mix problem, have you re-calibrated the carbs at all? other than move the needle? i think if you re-set the carbs to standard then tweek them it should sort it out . best bet would be to find a manual (try the search on the forum) or ask in a new topic? then go from there. at least then you know that the carbs are set up right! but as a basic setup the needles should be set half way, and the mix screw (air screw) should be 1 and 3/4 turns out. (im not sure on your model so dont hold me to it) im sure once you have sorted the mix out it will run sweet! its a ball ache i know and takes up a bit of time but when its done its done! good luck m8 and let me know how you get on! Link to comment Share on other sites More sharing options...
Moderator Airhead Posted March 9, 2011 Moderator Share Posted March 9, 2011 so it it running on both pots now but the back one is rich, the bike is much faster than before but it runs lumpy. is this correct? Link to comment Share on other sites More sharing options...
ABxv535 Posted March 9, 2011 Author Share Posted March 9, 2011 they are running ok now, plugs not getting black anymore that got sorted, but is still running lumpy if you rev it half way its okish, but giving it more revs its quite lumpy , only moved the needle up or down a notch ... we didn't touch the air/fuel setting at all, yes both cylinder are working and getting hot equally ... I don't really need to use the choke, we were just testing everything... Link to comment Share on other sites More sharing options...
Moderator Airhead Posted March 9, 2011 Moderator Share Posted March 9, 2011 they are running ok now, plugs not getting black anymore that got sorted, but is still running lumpy, only moved the needle up or down a notch ... we didn't touch the air/fuel setting at all "up or down a notch"...which is it? Put it back to spec, lifting the needle up a notch will make it lumpy Link to comment Share on other sites More sharing options...
ABxv535 Posted March 10, 2011 Author Share Posted March 10, 2011 We've tryed up a notch to give it more fuel we tought it was lumpy because needed more fuel, made it worse so we've brought it back down a notch , got a bit better but still not right! Link to comment Share on other sites More sharing options...
Paulwhite Posted March 10, 2011 Share Posted March 10, 2011 We've tryed up a notch to give it more fuel we tought it was lumpy because needed more fuel, made it worse so we've brought it back down a notch , got a bit better but still not right! oooo nooo ....its lumpy and drops when you pull back the trottle cause there is too much fuel. put it down a notch and it should get better. Link to comment Share on other sites More sharing options...
ABxv535 Posted March 10, 2011 Author Share Posted March 10, 2011 oooo nooo ....its lumpy and drops when you pull back the trottle cause there is too much fuel. put it down a notch and it should get better. That's what we've done now, but we've tried going up because we didn't know if it was starving for fuel, but made it worse so we've dropped it down to the position where it runs the best, but its still not ok, just better but i cant drop the needle anymore it's on the first setting , using half trottle its ok gets to 65/70 mph ok, but give it full trottle and gets lumpy again... could it be something to do with the air filter being a hi-flow? or the straight exhaust pipes? or fuel pump?? the exhaust on the bike don't look very old could it be that they need to be set for the carbs? or injectors upgraded? I want to get standard exhaust pipes anyway, just going to save some money and try to find some standard exhaust and then maybe book it in to a yamaha garage to try to sort it out,brought the bike home today from work... I had enough with it! we've tried everything we new, even called the yamaha garage and asked for advise and they've told us to do what we've already had done!... Would like to say thanks for everyones advise and help. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted March 10, 2011 Moderator Share Posted March 10, 2011 That's what we've done now, but we've tried going up because we didn't know if it was starving for fuel, but made it worse so we've dropped it down to the position where it runs the best, but its still not ok, just better but i cant drop the needle anymore it's on the first setting , using half trottle its ok gets to 65/70 mph ok, but give it full trottle and gets lumpy again... could it be something to do with the air filter being a hi-flow? or the straight exhaust pipes? or fuel pump?? the exhaust on the bike don't look very old could it be that they need to be set for the carbs? or injectors upgraded? I want to get standard exhaust pipes anyway, just going to save some money and try to find some standard exhaust and then maybe book it in to a yamaha garage to try to sort it out,brought the bike home today from work... I had enough with it! we've tried everything we new, even called the yamaha garage and asked for advise and they've told us to do what we've already had done!... Would like to say thanks for everyones advise and help. sound like its going rich at full bore. 1: is the main jet screwed in tight 2: could be a worn emulsion tube (thats what the needle moves up and down inside of) AKA needle jet. On old bikes with lots of miles they can wear oval and cause a rich fuel mix Link to comment Share on other sites More sharing options...
Paulwhite Posted March 11, 2011 Share Posted March 11, 2011 either that or someone has put different jets in.... the high flow air filter and straight through exhaust would cause the carb to run lean (if the carb is set to standard) as more air passes through with less sucking action. normally if the exhaust has been changed then the jets in the carb would be changed to compensate. best way to tell if the mix is rich or lean is look at ur spark plugs (black = rich, white = lean, orangy/straw like colour = spot on) its one of them jobs that takes a while to fix as you need to do this then that and see if it works then dismantle it again and change it slightly ect ect. it would be loads easier if you had a Haynes manual as you could determine if owt has been changed, and it also gives you the factory settings for the carb which would make a good starting point for you to go off. saves paying 40+ quid an hour for labor! but anyhoo hope you get it fixed ready for the nice weather Link to comment Share on other sites More sharing options...
ABxv535 Posted March 11, 2011 Author Share Posted March 11, 2011 Droping the needles to the lowest setting, so theres less fuel the plugs are ok not getting black... And the bike is using alot of fuel as well! That's the reson we've droped the needles to see if it would be better, and made it better, but still have problems at full trottle. Reason for our mechanic to think that when the've change the exhaust they never changed/upgraded the injectors or it may have a problem with the carbs or fuel pump not letting enough fuel at full trottle??? By the way the overflow on the front car started to leak again and the floats are good... Link to comment Share on other sites More sharing options...
ABxv535 Posted March 17, 2011 Author Share Posted March 17, 2011 When I think I'm getting somewhere with my bike something else goes wrong!!! , cant even start my bike now as soon i turn the key and put the switch to ON it's pissing out fuel from the breather pipe inside the chrome pod on the left side!! must have lost 2+ liters of fuel in a couple of min! I'm well pissed off with this bike! Link to comment Share on other sites More sharing options...
realrayzor Posted March 18, 2011 Share Posted March 18, 2011 Hi AB, sorry your having so much trouble with the carbs. Pity she's giving trouble cause it's anice looking bike. Have you considered bringing her to another mechanic to get a fresh set of eyes to her. Razor Link to comment Share on other sites More sharing options...
Moderator Airhead Posted March 18, 2011 Moderator Share Posted March 18, 2011 When I think I'm getting somewhere with my bike something else goes wrong!!! , cant even start my bike now as soon i turn the key and put the switch to ON it's pissing out fuel from the breather pipe inside the chrome pod on the left side!! must have lost 2+ liters of fuel in a couple of min! I'm well pissed off with this bike! Dohh, you have had the carbs apart, perhaps the float needle valve is out of place or stuck? I dont know how the bike is 'plumbed' so I cant be sure but does the carb overflow go this 'pod' you mention? Link to comment Share on other sites More sharing options...
ABxv535 Posted March 19, 2011 Author Share Posted March 19, 2011 Hi oldgitonabike , that's what I've done today... I dont know what you call them(pod, side covers???its the chrome things) ... breeder pipes go from the carbs into the left side one the right one got some electrical stuff and a black box in it ... there must still be some crap in the fuel pump ( i gess) that found its way in the carbs again,took the side cover on the left side carbs and the float needle valve was stuck on the front carb, took it off cleaned it and looks fine now, not leaking anymore... still don't know what is causing the problem at full throttle... will probably wait till i get my standard exhaust before trying messing with my carbs anymore otherwise will have to do it again after... anyone got a standard exhaust for sale??? Link to comment Share on other sites More sharing options...
ABxv535 Posted March 19, 2011 Author Share Posted March 19, 2011 Hi AB, sorry your having so much trouble with the carbs. Pity she's giving trouble cause it's anice looking bike. Have you considered bringing her to another mechanic to get a fresh set of eyes to her. Razor hi m8, I have talked to another mechanic (Yamaha garage), and they've told me to do the same we've already done, they've gave me the same advice as well given here... upgrade/ change the jets because of the straight trough exhaust, but seeing that i want to change them to standard ones i don't see the point of doing it! It is very annoying that every time i get something done some thing else goes wrong! I've spend a bit of money to make it look better than it was when i bought it... just need to get it to run like it should now... AB Link to comment Share on other sites More sharing options...
ABxv535 Posted April 16, 2011 Author Share Posted April 16, 2011 Finally got my bike running right! , the problem was the top of the hair filter cap, previous owner drilled a few holes on the top of the cap( I'm guessing to let more air in due to the bike running rich due to carb problems before i bought it) replaced the cap and its perfect now. so would like to say thanks for everyones help. Link to comment Share on other sites More sharing options...
fuff66uk Posted April 16, 2011 Share Posted April 16, 2011 Good to hear you have got it sorted mate,have you found another exhaust yet? Don't forget to keep me in mind for your pipes when you do find one Link to comment Share on other sites More sharing options...
Moderator Airhead Posted April 16, 2011 Moderator Share Posted April 16, 2011 Good result Link to comment Share on other sites More sharing options...
ABxv535 Posted April 16, 2011 Author Share Posted April 16, 2011 Good to hear you have got it sorted mate,have you found another exhaust yet? Don't forget to keep me in mind for your pipes when you do find one Hi m8, no i din't find anything yet, most on ebay are not great and expensive...new it too expensive!... but when i change them i will let you know. Link to comment Share on other sites More sharing options...
ABxv535 Posted April 16, 2011 Author Share Posted April 16, 2011 Good result cheers m8... Link to comment Share on other sites More sharing options...
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