twlou Posted July 15, 2011 Share Posted July 15, 2011 hi everyone, hope someone can help with my issue. i have a yamaha tw 125 and it cut out riding it the other day and when i went to start it again it just wouldn't turn over. if i push the start button you can hear it trying to start and the relay clicking, it's like it needs some extra power to get it to go.things i've checked:batteryignition coil leadpickup coilsource coilmain switchsidestand switchneutral relayneutral switchdiodestarter relayclutch switchfusei've also tried using a jumper lead from the +ve battery to the starter motor lead and it creates the same problem. i've taken the starter motor out, checked continuity on it, cleaned the brushes and the commutator too. still no joy. i'm not sure what i should do next really. any help is much appreciated, feeling a bit down as i want to get back out on it Quote Link to comment Share on other sites More sharing options...
twlou Posted July 15, 2011 Author Share Posted July 15, 2011 having a little rethink..... perhaps it is the battery that's knackered. although i did charge it and after checking it read just over 13v. driving me insane! i just don't know what else to check before i buy another battery Quote Link to comment Share on other sites More sharing options...
Guest Posted July 15, 2011 Share Posted July 15, 2011 i think if its showing 13 volts then the battery should be fine but im no mechanic. The clever ones have gone to the forum rally this weekend so you might not get the help you need until sunday evening but if you can hold off that long then they will be online and be able to point you in the right direction. Good luck Quote Link to comment Share on other sites More sharing options...
Takanta Posted July 15, 2011 Share Posted July 15, 2011 the battery may still be humped though, I had a battery like that , id give it a charge and kept it on the trickle charger but it still wouldnt shoot out enough leccy to start my bike , had to replace it .will it start if you bump start it? Quote Link to comment Share on other sites More sharing options...
twlou Posted July 15, 2011 Author Share Posted July 15, 2011 thanks guys. i'm going to replace the battery tomorrow and see if that helps. if not then i think i might cry! Quote Link to comment Share on other sites More sharing options...
whitedevil Posted July 15, 2011 Share Posted July 15, 2011 yeah try bump starting it or try another battery. if you have a multimeter check what voltage the battery drops to while starting. Your regulator/rectifier could have died and taken the battery with it.Are you getting a spark? Quote Link to comment Share on other sites More sharing options...
twlou Posted July 15, 2011 Author Share Posted July 15, 2011 will it start if you bump start it? tried this earlier today but it just made an odd clicking noise, didn't sound like a relay. either i wasn't going fast enough or the battery really is dead.whitedevil, definitely getting a spark as i checked that earlier too. if you watch the carb you can see it judder slightly when i hit the start button. hoping its not the reg/rect as it's quite pricey to replace Quote Link to comment Share on other sites More sharing options...
twlou Posted July 16, 2011 Author Share Posted July 16, 2011 quick update, i've ordered a new battery, starter relay and reg/rectifier so hopefully this will sort out all my issues. managed to get all that for £50 Quote Link to comment Share on other sites More sharing options...
twlou Posted July 16, 2011 Author Share Posted July 16, 2011 just made this video so everyone can get a better idea of what i'm bleating on about i noticed that you can here a faint "coughing" from the exhaust when i try starting it too. Quote Link to comment Share on other sites More sharing options...
Guest Hodgy Posted July 16, 2011 Share Posted July 16, 2011 Just watched your video, the battery seems fine, the engine is turning but not fireing, the starter relay is obviously working and I suspect the reg/rect is ok too, sorry.If the plug is sparking, then the other thing is fuel, could one of the fuel lines be kinked, stopping the fuel? Is it a vacuum operated tap, if so has the diaphram split or the vacuum hose come off, starving the bike of fuel? Hope you manage to get it started Quote Link to comment Share on other sites More sharing options...
N1NJA Posted July 16, 2011 Share Posted July 16, 2011 You have no spark there, have you checked your plug(s)? What condition are they in? Quote Link to comment Share on other sites More sharing options...
twlou Posted July 16, 2011 Author Share Posted July 16, 2011 You have no spark there, have you checked your plug(s)? What condition are they in? i've just done a spark plug test and i can see a little spark. changed the spark plug too If the plug is sparking, then the other thing is fuel, could one of the fuel lines be kinked, stopping the fuel? Is it a vacuum operated tap, if so has the diaphram split or the vacuum hose come off, starving the bike of fuel? not sure if it's a vacuum tap, how would i check this? and i honestly have no idea where i'm looking for the vacuum hose either so could you point me in the right direction?if it helps, i took the fuel hose from the tank off briefly to see if fuel coming through and it is. also i turned the screw out slightly by the float bowl to check fuel was getting there and it is. Quote Link to comment Share on other sites More sharing options...
twlou Posted July 16, 2011 Author Share Posted July 16, 2011 oh, and just thought i'd mention that when i pulled the spark plug out it was wet....is that normal? Quote Link to comment Share on other sites More sharing options...
whitedevil Posted July 16, 2011 Share Posted July 16, 2011 Is there fuel in the carbs? open the drain screw on the bottom and see if fuel comes out. You could also remove the air filter and spray some starter fluid, wd-40 etc in there and see if the engine fires, if it does you know its fuel if it doesnt then its probably not getting a spark. You said its getting a spark but it may be to weak to start the engine. I would first check the carb for fuel, then try starter fluid in the air box, then service the ht lead (remove the boot, cut 1/4 inch off the wire, strip it to get a good connection then replace the boot.) if its still not starting change the plug. Quote Link to comment Share on other sites More sharing options...
Guest Hodgy Posted July 16, 2011 Share Posted July 16, 2011 Right if the spark plug is wet, fuel is obviously getting through, perhaps too much though?You could of flooded the engine, causing it not to start, or maybe the spark isn't strong enough to get the engine to fire.Is the choke on, or is the cable stuck with the choke on? have a look and make sure all is well with the cable and the choke is operating.Try drying the plug off, charge the battery up and try starting it again, if it turns for a while without starting, try opening the throttle whilst cranking the engine, see if that helps. Quote Link to comment Share on other sites More sharing options...
whitedevil Posted July 16, 2011 Share Posted July 16, 2011 just seen your new post. If its wet it means your flooding it. could be a stuck float in your carb. give the carb a few taps with a screwdriver. turn the bike over a few times without the plug in to get rid of the excess fuel. then try again. Quote Link to comment Share on other sites More sharing options...
Bogof Posted July 16, 2011 Share Posted July 16, 2011 Check the kill switch? Quote Link to comment Share on other sites More sharing options...
twlou Posted July 16, 2011 Author Share Posted July 16, 2011 hi guys. right, i've just been out had the carb off and had a peak inside. not quite sure what to look for but the was no obvious signs of dirt in it. checked the float bowl too, all clean and clear there. i've just done the spark plug test again and as i did it i could see into the plug hole and there was fuel spraying in there. one thing i thought, isn't it supposed to be a fine spray, not spurting in there? i've had the air filter off too and it was quite dirty with bits of fluff so i cleaned that. noticed that it was wet at the bottom, gave it a sniff and smelt like fuel to me. is that normal? tried spraying with wd40 as suggested. just seen your new post. If its wet it means your flooding it. could be a stuck float in your carb. give the carb a few taps with a screwdriver. turn the bike over a few times without the plug in to get rid of the excess fuel. then try again. so if it is flooded, take spark plug out and turn it over a few times? and why would too much fuel be getting in - problem with the jet in the carb maybe? Is the choke on, or is the cable stuck with the choke on? have a look and make sure all is well with the cable and the choke is operating. choke cable looks rusty on the carb side and stiff to pull Quote Link to comment Share on other sites More sharing options...
Guest Hodgy Posted July 16, 2011 Share Posted July 16, 2011 It could be the choke sticking on then, or if not that, there is a valve in the float bowl that stops the fuel from overfilling the carb, it will be where the fuel goes into the carb, but you get at it from inside the carb when the float is removed, I would think that could have some dirt in it stopping it closing fully Quote Link to comment Share on other sites More sharing options...
twlou Posted July 16, 2011 Author Share Posted July 16, 2011 It could be the choke sticking on then, or if not that, there is a valve in the float bowl that stops the fuel from overfilling the carb, it will be where the fuel goes into the carb, but you get at it from inside the carb when the float is removed, I would think that could have some dirt in it stopping it closing fully right ok, will have the carb off again tomorrow and have a look. will cleaning this up help with the fuel issue?may try the wd-40 trick again or could i risk spraying too much? i don't want to blow anything! Quote Link to comment Share on other sites More sharing options...
N1NJA Posted July 16, 2011 Share Posted July 16, 2011 Sounds exactly like what mine is doing at the moment. I've just had my carbs off to give them a clean and now I've put them back they are flooding. If you have a haynes manual it will tell you the amount of fuel that is stored in the float bowl and what height the floats should be set to. Just to try this, I turned my fuel off, held the throttle right open and kept my finger on the start button, eventually the bike started although very rough and obviously died as soon as the remaining fuel in the pipework had been spent. Quote Link to comment Share on other sites More sharing options...
twlou Posted July 16, 2011 Author Share Posted July 16, 2011 Just to try this, I turned my fuel off, held the throttle right open and kept my finger on the start button, eventually the bike started although very rough and obviously died as soon as the remaining fuel in the pipework had been spent. that's an interesting thought, will try that tomorrow have had the carb completely off now and given it a good clean. checked that valve Hodgy and it seems fine. blew some compressed air through all the holes too so will see what happens tomorrow providing the weather holds up....it's not looking good though Quote Link to comment Share on other sites More sharing options...
twlou Posted July 17, 2011 Author Share Posted July 17, 2011 right guys, guess what i found after putting the carb back on just now.....the crankcase breather hose was detached from the airbox - what does this actually do?unfortunately after putting everything back together it still doesn't run another issue, bought a new spark plug this morning and when doing the test, no spark so how can I sort this? Quote Link to comment Share on other sites More sharing options...
Bogof Posted July 17, 2011 Share Posted July 17, 2011 Check the kill switch? Did you? Quote Link to comment Share on other sites More sharing options...
twlou Posted July 17, 2011 Author Share Posted July 17, 2011 Check the kill switch? Did you? i'm not sure if that's supposed to be a joke? but the answer is, yes i did Quote Link to comment Share on other sites More sharing options...
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