Cosmo Posted June 5, 2012 Share Posted June 5, 2012 Hello there, My name is Phil and i thank you for reading this. I am in the process of converting the electrics on my DT175 MX to 12 volts after researching the various threads. All bulbs, the battery and the flasher unit have been replaced but i'm struggling to find a suitable voltage regulator. Mine has a single yellow/white wire coming from it and i guess that the case is the actual earth connection that bolts to the frame. However, all replacement 12 volt regulators seem to have many wires and i'm struggling to find anything with a single wire to retrofit. If anybody has any ideas, please let me know. I don't mind modifications and if i have to alter something with four wires to fit, so be it! But i'll need somebody to hold my hand so that i know what wire goes where. One of the threads suggested using a regulator from a Honda cub C90 but that has a connector with four wires. Alas, i should have checked before ordering it and i've now spent an afternoon searching for single wire regulators from all of the major manufacturers to no avail, with the exception of a part from a snowmobile that may do the job! However, i'll try the local pool of knowledge first. Thanks in advance and best regards, Phil Link to comment Share on other sites More sharing options...
NE0 Posted June 7, 2012 Share Posted June 7, 2012 Hi Phil welcome to the YOC hope you enjoy your visits and you'll learn a lot I'm sure. Firstly, the one thing which gets many of the guys backs up here, is not posting an introduction about yourself in the newbie section. Doesn't have to be much:- hi my names so and so , been into bikes for blah blah, riden all sorts of bikes including harleys etc etc, you get the drift? That way , you'll find the guys respond much quicker to posts and we tend to have a bit of a banter, some guys will even bend over backwards to help you....with knowledge that is not in any other context!! That said, you mention one thread which suggests using a 4 wire Cub 90 regulator, if it's my thread, then i think you need to re-read it in full and not speed read it, because you've not wasted your money as you have the right one. You wanted to try the local pool of knowledge first .............well you're in it! Link to comment Share on other sites More sharing options...
Speedshop Posted June 8, 2012 Share Posted June 8, 2012 we have these on our website p/n rr12 on the regulator page. I use these for the XT 500 conversion and they work well. I can supply the connection info and plugs if required www.rexs-speedshop.com Link to comment Share on other sites More sharing options...
Cosmo Posted June 11, 2012 Author Share Posted June 11, 2012 Hello there Noe and Rex, Many thanks for the reply and i apologies regarding not putting anything in the newbie section - i am new too forums and i am struggling. Needless to say, i didn't even realise that you guys had replied until i checked the forum itself. I was expecting the forum to notify me via e-mail that somebody had posted a reply but again, i am new to this, so thanks for holding my hand. (i will post something on the newbie section after this reply) Well, this is the saga so far - all bulbs have been changed and the flasher unit. The yellow/white wire to the regulator which is mounted onto the frame next to the carb has been left disconnected for now. A test run shows that the bike is OK in first and second but if i rev over 5000 rpm in any other gear, the bike dies until the revs go below this limit. My guess is that this is electric related, as the sound the motor makes is identical to when the kill switch is operated. (i tried to replicate the faults in various ways) To answer Rex's post - i will order one of these 12 volt regulators from you and i thank you for taking the time to reply to my post - it helps to have people in the know! And to answers Neo's post - once again, i thank you for your advice - you are both saviours! But regarding the regulator from the C90 cub - where does the existing regulator live? I cannot find it! The part that i have found with Stanley Regulator written on it is the finned encapsulated unit that bolts to the frame ahead of the carb. This is the one with the yellow/white wire. Maybe i have speed read the post but re-reading it leaves me none the wiser. I have the wiring diagram from the Haynes manual - and yes, there are some errors on there - but for the life of me, i cannot find a 4-wire regulator like that i bought for the Honda cub. Where is the regulator that you wish me to change? And if it is different to the one by the carb, what is that regulators function? I'm not referring to the rectifier - i know where that is. Many thanks once again and i hope to make the bike rideable once again. Best regards and thanks to all who read and even more thanks to those who responded! Phil Link to comment Share on other sites More sharing options...
Cosmo Posted June 11, 2012 Author Share Posted June 11, 2012 PS - I apologise about mis-spelling your user name, Neo... Link to comment Share on other sites More sharing options...
Speedshop Posted June 11, 2012 Share Posted June 11, 2012 You won't find a 4 way regulator on the bike as standard. You'll have to modify the bike to fit this type. I'm in the process of writing a step by step guide for he XT. I think there is a guide on here for the DT Link to comment Share on other sites More sharing options...
Cosmo Posted June 17, 2012 Author Share Posted June 17, 2012 Hello there Neo and Rex, Many thanks for your input on this. I have read Neo's page thoroughly and all of the information is there, as he says. I have followed it methodically and made a loom and all seems OK. I do have a problem where the machine dies under load but i'll start another help topic for that, as it may not be related. As far as i'm aware, the coils are for the lighting and the running of the machine. I have tried to follow the Haynes manual and they seem to copy the data from other manuals, so there is quite a lot of info missing and i admire Neo's skills for decoding this! I will briefly mention the fault, just in case it is related but my instincts tell me the fault lies elsewhere... In general riding, the machine will rev to 5000 rpm approx. If you gently use the throttle, it will rev beyond this. This makes me think that it isn't the coils. If i've got the information right, there is one coil for the lower revs and another for the higher revs. Checking the resistance, they are within tolerance. (the additional could being for the lighting) However, the Haynes manuals states a 4th red wire from the magneto which my bike doesn't have. (Red/white, brown and black wires only - the other wires going to a modular connector and don't apparently seem related to the actual running of the machine) I initially suspected ignition - if i ride along and use the kill switch, the sounds and symptoms are identical. However, the bike will run off the magneto alone, so that makes me think it could be fuelling. Then again, with fuelling, it would surely splutter and hesitate if running lean? The bike starts first kick. Tick over is smooth. Running with the choke makes no difference to the symptoms, although it does change the running characterises of the running, as it's rich. I suspected the float levels and i have no idea how to set these - if it's in the manual, i've missed it. But they are unchanged from when the machine was running on 6 volts. However, the bike will freely rev to towards the redline offload, so i'm not convinced it's the coils unless they are breaking down. Any ideas? Is it something to do with the conversion? The only parts changed were what Neo instructed. I am electrically minded but magnetos are a hocus-pocus type of thing and far removed from repairing radio and televisions, which is what i was trained in! And as the bike had stood for 8 years, i cannot say whether it ran fine on 6 volts prior to the conversion. (it used to prior to storage) And i'm loathe to backwards engineer the bike to 6 volts just to see...(i have this sinking feeling that i may have to in a process of elimination but i'll check the local knowledge pool first...) I'll hold off a new posting just to get your thoughts and i thank everyone everyone who has supported me in this quest. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 17, 2012 Moderator Share Posted June 17, 2012 the early bikes has the red wire, they had two 'source' coils yours doesnt only the one. Which leads me to question your within tolerance statement because they have different values between the mk1 and mk2 ignitions. Do you want me to post up a head to toe tutorial for checking the ignition system...better than any haynes manual if i say so myself Link to comment Share on other sites More sharing options...
NE0 Posted June 17, 2012 Share Posted June 17, 2012 Hi phil, Rest assured your problem won't be related to the 12v conversion. The conversion is only a means to charge the battery and run the electrics, ie lights and horn. The ignition is NOT effected by the conversion. That said also rest assured if you've got Paul on the case, you can't go wrong, He's a sort of Yamaha demi-god around here!........... Demi?.......no he's the main one!!! Notch up another neo-conversion! Link to comment Share on other sites More sharing options...
Cosmo Posted June 17, 2012 Author Share Posted June 17, 2012 Hello there once again! Yes Neo, your advice was spot on regarding the conversion and i didn't see the wood for the trees regarding the regulation. Had i bothered to read it properly first time, it would have been a lot clearer but you know how it is - you get excited, can't wait to start, etc. I guess i should really read the instructions and i'm old enough to know better... And getting back to my running problem, i have been researching this subject and i see that Airhead was writing to Vambo about the same issue back in 2009. I don't think Vambo evert did let us know if he cured the problem but i realise the information was quite in depth. Regarding the tolerance, you are correct, my machine doesn't have the red wire but the readings didn't seem far off what Haynes published. I say not far off - when checking resistance values on TV or radio, short of actually removing the part that you are checking, a value close to or below is acceptable because other things affect the reading. I realise magnetos are a different ballgame and if it should be specific, please advise. (tolerances accepted, of course) This is another thing i've found with Haynes manuals - i have found through experience that they often take their information from another source. They have you believe they tear the vehicle in question part but this isn't true. I had a Peugeot which had letters to identify the wires but no table to say what letters were for which colour. I though i must be misreading it but i found the Peugeot factory manuals and they didn't tell you, either. And Haynes just copied what was in the factory manuals and hence duplicated the error. (and for those who are wondering did i ever sort it, the answer was yes - but through my own knowledge and also having a second identical vehicle to refer to - and this is the rule with Haynes manuals rather than the exception...) So yes please, do post that head to toe tutorial... And going back to the plot...if i switch the kill switch off, the sounds are identical. I can open the throttle and you get that open carb sound that has no ignition (as the switch is off) but with the switch in run position, the sounds are identical. Yet others say its the main jet on the carb. I admit, the carb has been apart and cleaned using carb cleaner and an airline but i thought i was pretty methodical and past experience with fuelling usually allows the engine to run, albeit roughly. But i only know what i know and haven't experienced this kind of fault before, so i'm over my head with this one - i'll keep an open mind... Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 17, 2012 Moderator Share Posted June 17, 2012 it may take a little time to resolve your issues, gut feeling is carb, does it improve with choke on, ie lose the induction roar of a non firing engine? meanwhile.... DT175MX Ignition checks There were two versions of ignition systems on DT175MX bikes. The mk1 version from the earlier bike had a 7 wire CDI the early bikes had a round section swing arm. The mk2 version had a 6 wire CDI, the red wire is absent on these. These bikes have a square section swing arm. The HT cap (AKA spark plug cap) unscrew it off the HT lead, it is supposed to be a resistor cap so should be around 5K Ohms The ignition coil primary...Orange wire to battery neg should be 1 Ohm +- 10% The ignition coil secondary...HT lead to battery neg should be 5900 Ohms +- 20% If the readings are much higher, check the ignition coil has a clean ground connection. Yes and the ignition coil mounting is a wiring harness ground point too, so check its clean and bright there. Disconnect all the wires from the CDI. Then using your multimeter on the loom side of the connectors. Black probe on a clean part of HT coil ground point Red probe on...... Orange, Meter to 200 Ohms, expect 1 Ohm (HT coil primary) Brown, Meter to 2k Ohms, expect 420 Ohms for mk1 and 300 Ohms for mk2 (Magneto charge coil) White/Red, Meter to 200 Ohms, expect 12.4 Ohms for mk1 and 10 Ohms for mk2 (Magneto pulser coil) Red, Meter to 200 Ohms, expect 13.6 Ohms for mk1 only. (Source coil 2 or high speed coil) Black female connector, Meter to 200 Ohms, expect dead short repeat for black male connector Any difference in the results for the two black wires may possibly be rectified by cleaning the front engine mounting bolt and a little of the frame behind the bolt head, then tighten to torque spec. Black/White, Meter to 20K Ohms, with ignition off expect dead short, with key on expect open circuit, with kill operated expect dead short (Engine kill operation) If all these tests are good you would be well advised to try another CDI. If they are not good...reading higher...disconnect and clean any plugs/sockets you find along the way, if the magneto coils are reading lower, new ones needed if more than 10%...or so the book says Finally, if you are working with a box full of mixed parts! Mk1 1 flywheel is Mitsubishi F3T250, it has two slots in the face of the flywheel Mk2 flywheel is Mitsubishi F3T251, it has four slots in the face of the flywheel Link to comment Share on other sites More sharing options...
Cosmo Posted June 18, 2012 Author Share Posted June 18, 2012 The choke makes no difference. I tried this while precariously riding along. If it was running lean, i'd expect it to pick up or splutter. Of course, if it is off load and the engine is running, the choke does make a difference- the engine bogs down, as you would expect. While i am no novice, i am no expert either and i realise its a process of elimination. I will print out your ignition section and digest it later and then re-read it. Regarding the coils, you say the earlier model had two coils and the red wire and the later model didn't have the red wire. Does this mean that it only has one coil? If so, would that mean the stator either works or it doesn't? I'm not taking into account it could be breaking down, etc. But with two coils, the second coil could be breaking down under higher revs under load whereas with only one coil, is it a go/no go situation? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 18, 2012 Moderator Share Posted June 18, 2012 what i am saying is...yes the later mk2 had only 1 coil and no red, however the coil ohms value is different to the larger of the 2 coils in the mk1. You said you checked in the haynes manual and yours was in spec...but which model were they talking of? perhaps your stator coil is indeed out of spec?...all will become clearer when you study what i posted. do the checks that are applicable to yours it does seem it may be an electrical issue now that the choke made no difference Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 18, 2012 Moderator Share Posted June 18, 2012 The choke makes no difference. I tried this while precariously riding along. If it was running lean, i'd expect it to pick up or splutter. Of course, if it is off load and the engine is running, the choke does make a difference- the engine bogs down, as you would expect. While i am no novice, i am no expert either and i realise its a process of elimination. I will print out your ignition section and digest it later and then re-read it. Regarding the coils, you say the earlier model had two coils and the red wire and the later model didn't have the red wire. Does this mean that it only has one coil? If so, would that mean the stator either works or it doesn't? I'm not taking into account it could be breaking down, etc. But with two coils, the second coil could be breaking down under higher revs under load whereas with only one coil, is it a go/no go situation? The early bikes had 2 coils for the ig and one for the lighting, the later had 1 for ig and 1 one for lighting with a different more advanced cdi. I agree with Paul, its sounding more fuel than electrical. Did you note the jet sizes etc when she was apart. Have you changed anything in the carb. Like the float height or replaced any components for example. Link to comment Share on other sites More sharing options...
Cosmo Posted June 18, 2012 Author Share Posted June 18, 2012 There was sediment in the tank, so i did a tank clean and also stripped the carb. I could have inadvertently adjusted the float levels without realising, although i was careful not to. As for the markings on jets, no, i didn't notice but it is the same ones that it has always had and it ran fine prior to storage. However, i've just bought myself another air gun and i will strip the carb and use this to blast the airways with some carb cleaner and i'll make a note of the sizes. I'll also make a point in digesting the info that was sent regarding checking the readings in the info that was sent to me. As i've only just walked through the door, i haven't had the time to read them as of yet but i will! Regarding the readings that i said were in spec - the Haynes manual is rather vague here. It refers you to the beginning chapter where there is no mention of it and if you go further back, it's for the earlier variants. The fact that the listed readings referred to this 4th red wire that i don't have, i can only assume that there are a different set of readings for the later model without this wire. All very misleading. Thank goodness for you guys and your pool of knowledge! Link to comment Share on other sites More sharing options...
Cosmo Posted June 19, 2012 Author Share Posted June 19, 2012 Would you be kind enough to clarify some points for me please, my friend? I hate calling you by your forum name of Airhead - it seems like an insult - except i know it refers to the love of air cooled machines - however, i can't help feeling a pang of guilt referring to you by your forum name... The HT cap is a little high at 6.3 ohms. It may need replacing. Does anybody know where i can locate original parts rather than pattern items? I like to keep the bike original where possible... Ignition coil primary is 1.8 ohms. Is this within spec?It's almost double the specified 1 ohm reading. (i could have answered my own question here but i want to be sure...) Ignition coil secondary within specs at 5.8 kilo ohms. (5,800 ohms) Now this is where i'm struggling: >>>Black probe on a clean part of HT coil ground point Red probe on...... >>>Orange, Meter to 200 Ohms, expect 1 Ohm (HT coil primary) What orange wire? There isn't one from the magneto. There is an orange wire from the loom to the LT side of the coil. But not in the cluster coming out from the magneto. Back to the test results... >>>Brown, Meter to 2k Ohms, expect 300 Ohms for mk2 (Magneto charge coil) I'm getting 301 ohms. >>>White/Red, Meter to 200 Ohms, expect 10 Ohms for mk2 (Magneto pulser coil) I'm getting 12.4 ohms. >>>Black female connector, Meter to 200 Ohms, expect dead short I'm getting a dead short. >>>repeat for black male connector There is little difference when i repeat the tests. I need more help on this one, though... >>>Black/White, Meter to 20K Ohms, with ignition off expect dead short, with key on expect open circuit, with kill operated expect dead short (Engine kill operation) Where is this black.white wire? It isn't coming from the magneto. Please assume i know nothing! You won't go far wrong and i won't be insulted! I await your response with baited breath! Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 19, 2012 Moderator Share Posted June 19, 2012 Would you be kind enough to clarify some points for me please, my friend? I hate calling you by your forum name of Airhead - it seems like an insult - except i know it refers to the love of air cooled machines - however, i can't help feeling a pang of guilt referring to you by your forum name... By all means you can call me Paul...and you are? The HT cap is a little high at 6.3 ohms. It may need replacing. Does anybody know where i can locate original parts rather than pattern items? I like to keep the bike original where possible... Get yourself a new NGK 5k ohms cap Ignition coil primary is 1.8 ohms. Is this within spec?It's almost double the specified 1 ohm reading. (i could have answered my own question here but i want to be sure...) Ignition coil secondary within specs at 5.8 kilo ohms. (5,800 ohms) I take it you subtracted the figure you get from your meter leads only? if so it's out of 10% spec Now this is where i'm struggling: >>>Black probe on a clean part of HT coil ground point Red probe on...... >>>Orange, Meter to 200 Ohms, expect 1 Ohm (HT coil primary) What orange wire? There isn't one from the magneto. There is an orange wire from the loom to the LT side of the coil. But not in the cluster coming out from the magneto. as it says...its the HT coil primary and the tutorial says you should be checking at the disconnected plugs and sockets to the CDI...It's orange there, you already said that yours was high at 1.8 ohms...was this directly at the HT coil and not the loom connector to the CDI? Back to the test results... >>>Brown, Meter to 2k Ohms, expect 300 Ohms for mk2 (Magneto charge coil) I'm getting 301 ohms. Good >>>White/Red, Meter to 200 Ohms, expect 10 Ohms for mk2 (Magneto pulser coil) I'm getting 12.4 ohms. Its seems that someone somewhere along the line has replaced the pulser coil for a mk1 jobbie...dohh! I expect this will inadvertantly advance the ignition somewhat! >>>Black female connector, Meter to 200 Ohms, expect dead short I'm getting a dead short. >>>repeat for black male connector There is little difference when i repeat the tests. Good I need more help on this one, though... >>>Black/White, Meter to 20K Ohms, with ignition off expect dead short, with key on expect open circuit, with kill operated expect dead short (Engine kill operation) Where is this black.white wire? It isn't coming from the magneto. Please assume i know nothing! You won't go far wrong and i won't be insulted! I await your response with baited breath! Speed reading again lol...at the disconnected (loom side) CDI terminals Link to comment Share on other sites More sharing options...
Cosmo Posted June 19, 2012 Author Share Posted June 19, 2012 >>>By all means you can call me Paul...and you are? My name is Phil! >>>Get yourself a new NGK 5k ohms cap I will order one! >>>I take it you subtracted the figure you get from your meter leads only? if so it's out of 10% spec No, i didn't, that was the reading, as is. >>>its the HT coil primary and the tutorial says you should be checking at the disconnected plugs and sockets to the CDI...It's orange there, you already said that yours was high at 1.8 ohms...was this directly at the HT coil and not the loom connector to the CDI? I think this is a case of me not digesting it properly. Maybe i can't see the wood for the trees... I haven't removed any covers for access to the CDI, so this will be my next stage of testing. I checked at the connectors that come out from the loom...assumptions - and yes, i got it wrong, Mr. Mainwaring... >>>Its seems that someone somewhere along the line has replaced the pulser coil for a mk1 jobbie...dohh! I expect this will inadvertantly advance the ignition somewhat! I'll get you to advise on that and no doubt it will depend on what my findings are when i return to the testing of things. Considering i bought the bike when it was less than six months old, i'd be somewhat surprised but the pulser coil has never been knowingly replaced while in my ownership. (and i'm the second owner) >>>Speed reading again lol...at the disconnected (loom side) CDI terminals All noted, Captain! Some things are so obvious. However, re-reading this, it would still have been ambiguous to me...disconnect all wires from there CDI...well, i should have done so directly at the CDI but i wrongly assumed at the loom without gaining access to said CDI - doh! So not only am i learning about the bike but you're training my mind as well! No wonder you're stressed! Ill keep you updated and i'll have a look tomorrow. Thanks once again to one and all! Link to comment Share on other sites More sharing options...
Cosmo Posted June 20, 2012 Author Share Posted June 20, 2012 Hello there Paul, Cynic, Neo and the rest of our avid followers! I have taken three steps forward and one step back...and i am still struggling. I have removed the flywheel - it is a MItsubishi F3T251 and there are two coils. There are only five wires leading from this, with the exception of what appears to be the neutral switch wire, which is turquoise. The colours are Black, Brown, White with red, yellow and green. I did originally request the location of the CDI but a search of e-bay has shown me pictures of what i should be looking for. I had no idea of what it looked like or it's location but now that i know that it's a plastic black box with many wires, i should be able to test things a little further. This is good, because it means that i don't have to remove the backplate that the two coils are connected to in the magneto. As i'm new to forums, i do not know how to upload photo's, otherwise i'd have done so... In the meantime, a spark plug cap has been ordered... Link to comment Share on other sites More sharing options...
Speedshop Posted June 24, 2012 Share Posted June 24, 2012 Failing to rev is normally an over rich mixture Link to comment Share on other sites More sharing options...
Recommended Posts