Clarky T. Posted September 27, 2009 Share Posted September 27, 2009 Hi Guys, Just wondering if anyone can help with a small but irratating fault with my 82 Yam rd250lc? When started(Always first kick) the bike idles perfectly and will take the throttle as it should and then will return to a normal idle (1000rpm).It has now developed a intermitant over revving when the throttle is blipped (parked)The bike will rev to approx 4000 revs and will stay there even though the throttle is closed and will eventually return to it,s normal idle? You would swear it was a sticking throttle cable or sliders but these are all fine?The carb settings are all good and had,nt been touched prior to this fault...It,s doin me head in!! Could it possibly be taking in air somewhere or dodgy needles? Any help would be very much appreciated, Clarky!! Link to comment Share on other sites More sharing options...
JimR Posted September 27, 2009 Share Posted September 27, 2009 Hi Guys, Just wondering if anyone can help with a small but irratating fault with my 82 Yam rd250lc? When started(Always first kick) the bike idles perfectly and will take the throttle as it should and then will return to a normal idle (1000rpm).It has now developed a intermitant over revving when the throttle is blipped (parked)The bike will rev to approx 4000 revs and will stay there even though the throttle is closed and will eventually return to it,s normal idle? You would swear it was a sticking throttle cable or sliders but these are all fine?The carb settings are all good and had,nt been touched prior to this fault...It,s doin me head in!! Could it possibly be taking in air somewhere or dodgy needles? Any help would be very much appreciated, Clarky!! Hi Clarky I guess you have an air leak ... check the rubber tube between the 2 carbs or if not fitted the metal tube across the reed blocks Regards Jim Link to comment Share on other sites More sharing options...
Moderator Airhead Posted September 27, 2009 Moderator Share Posted September 27, 2009 Hi Clarky, Try spraying the inlet manifolds or any pipe that connects them to each other with WD40 when the engine is 'racing'. Any notable change in revs will be your air leak. ...Paul Link to comment Share on other sites More sharing options...
up.yours Posted September 27, 2009 Share Posted September 27, 2009 thanks very much lads ,my 350 developed this very fault only this afternoon,isnt that erie ,but i found that iff i pull on the throtte cable near the grip it revs up.what may have come loose .(sorry to muscle in on your topic but we may have the same problem)my tickover is about 3500. Link to comment Share on other sites More sharing options...
Clarky T. Posted September 27, 2009 Author Share Posted September 27, 2009 thanks very much lads ,my 350 developed this very fault only this afternoon,isnt that erie ,but i found that iff i pull on the throtte cable near the grip it revs up.what may have come loose .(sorry to muscle in on your topic but we may have the same problem)my tickover is about 3500. No Bother,muscle away....I just wanna get this sorted as it spoils the ride!! Link to comment Share on other sites More sharing options...
JimR Posted September 27, 2009 Share Posted September 27, 2009 thanks very much lads ,my 350 developed this very fault only this afternoon,isnt that erie ,but i found that iff i pull on the throtte cable near the grip it revs up.what may have come loose .(sorry to muscle in on your topic but we may have the same problem)my tickover is about 3500. Hi Thats a badly routed cable Regards Jim Link to comment Share on other sites More sharing options...
up.yours Posted September 27, 2009 Share Posted September 27, 2009 (edited) cheers me mateys ill take a look tomoz its to dark now. it just seems odd that it worked fine for 11 months Edited September 27, 2009 by up.yours Link to comment Share on other sites More sharing options...
JimR Posted September 28, 2009 Share Posted September 28, 2009 cheers me mateys ill take a look tomoz its to dark now. it just seems odd that it worked fine for 11 months Dont forget the cable(s) may have streched and with bad routing may now be pulling incorrectly check that both slides appear in the balance windows (or removable screws dependant on carbs fitted) if they dont pull together adjust the adjusters on the top of the carbs then adjust at the grip to achieve the correct free play it is possible that the cable has snaged on the bottom yoke and may have got worse over a period of time Regards Jim Link to comment Share on other sites More sharing options...
Joshua2 Posted September 29, 2009 Share Posted September 29, 2009 UP.YOURS - Its two minutes to remove the petrol tank and make sure the cables are routed correctly. It wouldn't hurt to give them a bit of oil and check the carb slide balance. Paul is correct when he says 'spray WD40' around the intake manifold to see if there is any difference in tickover. Sounds like a perished manifold/r.v to me. WD is safer than petrol. ATB J Link to comment Share on other sites More sharing options...
up.yours Posted October 2, 2009 Share Posted October 2, 2009 as you know ?im pre mixing so can i cut and remove the oil pump cable section as its badly frayed.or will it all fall apart. Link to comment Share on other sites More sharing options...
Moderator mervin Posted October 2, 2009 Moderator Share Posted October 2, 2009 you should be able to remove the oil pump cable, cut it and then if it is the same as the aircooleds you shoukld be able to remove the top of the junction box and take the remainder out, if yo leave the pump in make up a pipe system so it can circulate some oil or get a blanking plate from Nigel kimber or Norbo mev Link to comment Share on other sites More sharing options...
Rosscoe Posted October 8, 2009 Share Posted October 8, 2009 Hi Guys, Just wondering if anyone can help with a small but irratating fault with my 82 Yam rd250lc? When started(Always first kick) the bike idles perfectly and will take the throttle as it should and then will return to a normal idle (1000rpm).It has now developed a intermitant over revving when the throttle is blipped (parked)The bike will rev to approx 4000 revs and will stay there even though the throttle is closed and will eventually return to it,s normal idle? You would swear it was a sticking throttle cable or sliders but these are all fine?The carb settings are all good and had,nt been touched prior to this fault...It,s doin me head in!! Could it possibly be taking in air somewhere or dodgy needles? Any help would be very much appreciated, Clarky!! Hi Clarky, Did you end up sorting the problem out? If so what was it in the end? I hope it is running nicely for you again and not spoiling your fun. Regards Rosscoe Link to comment Share on other sites More sharing options...
JimR Posted October 10, 2009 Share Posted October 10, 2009 you should be able to remove the oil pump cable, cut it and then if it is the same as the aircooleds you shoukld be able to remove the top of the junction box and take the remainder out, if yo leave the pump in make up a pipe system so it can circulate some oil or get a blanking plate from Nigel kimber or Norbo mev I cannot see the point of this for the price of a cable unless you would really like to run a mix & adjust the jetting in order for the bike to run right. Take into account that the bike is a good few years old and parts will be worn so tricks from the past (when the bike was new) may no longer work correctly. I remember years ago following some hot mods for my YL1 (tbh I should have known better ) and the YL1 was distroyed in about 500 miles ... cause was the mods assumed the bike was not worn and did not give any margin for a bike that had been around the block a few times ... just be careful it may :rolleyes:cost a bit Regards Jim Link to comment Share on other sites More sharing options...
up.yours Posted October 17, 2009 Share Posted October 17, 2009 the throttle cable going to the carb has frayed,so i purchased a new one the bikes layed up for now because i cant disconect the cable at the slider side ,can you tell me how its done please. Link to comment Share on other sites More sharing options...
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