copemech Posted May 13, 2014 Report Share Posted May 13, 2014 The good, bad, and ugly! Well, if it just runs a bit and shuts off like you turned the key, that can be an ugly situation. Ignition is near certain culprit. Woodruff keys don't usually fix themselves, so I would rule that out if it runs normal while running. I am not a fan of taking resistance readings on these. You might find an open coil of something, but it seems it is usually the hall sensors that fail and I know of no way to properly test them. Would take some type dyno to do it I think. Steve at motoplat UK would be the overhauler of choice, although a week each way for post. Prolly cost half that of new. Last I knew, RYP had new only that comes with matching flywheel. Over $300 last I know, but good news is he will send you whatever you need for testing and you can return what you do not need as long as you don't screw it up. No real pattern on any of this, and the CDI may still be suspect, which makes a doner bike a real luxury here. Now that I think, Chris at Splatshop UK may have an o/h exchange unit he could send out and you would get the stator in a week or so. E-mail sales@splatshop.co.uk for availability if RYP has no o/h units. That is all I can tell you, good lock and keep us posted! Quote Link to comment Share on other sites More sharing options...
bigmark1972 Posted May 13, 2014 Author Report Share Posted May 13, 2014 Thanks Cope, Yeah I agree and am also not sure of the value of testing the coils in the stator when it's generally the hall effects switch that fails. AFAIK if I go with RYP the new ones will still come with the OEM hall sensors that are prone to fail? In that case I'd rather wait a week than possibly deal with this again shortly in the future. Probably better get one on the way from someone.... Going to have this bike for awhile won't kill me to have one on hand if it ends up not being the issue... -Mark Quote Link to comment Share on other sites More sharing options...
bigmark1972 Posted May 13, 2014 Author Report Share Posted May 13, 2014 (edited) Chris at Splatshop sent me a helpful email so I will share here for the benefit of others as it answers the question I had about the readings from the stator. Too be honest though looking at your test readings it looks like the stator might be ok, usually when they fail and the bike won't start one of the Blue, Black or Brown wires shows either a short circuit (0) or a open circuit (1), occasionally you get them reading correctly and they still don't run but usually if they read ok they will run or spark intermittently. I've asked him about testing the hall sensor as I am still wondering about that, will post his response (if any) Here is his response about the Hall sensor, so it seems you can test them; Yeah the reading from the Blue, Black or Brown wires are from the circuit board containing the Hall sensors but very occasionally (5% ish) they do still test ok but have a intermittent fault, these usually still run just badly. If they test bad i.e. a short circuit (0) or a open circuit (1) then they are always broken. Edited May 15, 2014 by bigmark1972 Quote Link to comment Share on other sites More sharing options...
copemech Posted May 14, 2014 Report Share Posted May 14, 2014 (edited) Chris at Splatshop sent me a helpful email so I will share here for the benefit of others as it answers the question I had about the readings from the stator. I've asked him about testing the hall sensor as I am still wondering about that, will post his response (if any) Catching an intermittent transistor in the failed state, open or shorted, that you may actually measure here is the issue. Would be better if it would just die! No idea which replacements Steve uses, All made in Tiawan! New is not bad, seems yours may have been around for awhile, your report is a bit different than most, with good running for short period then nothing. But I have seen so much weird stuff like that I never rule anything out! Hook up with Biff if you can, great guy and a wealth in himself. Edited May 14, 2014 by copemech Quote Link to comment Share on other sites More sharing options...
thats_a_five Posted May 14, 2014 Report Share Posted May 14, 2014 Sometimes you can "test" a hall effect sensor with heat. Take a hair dryer or heat gun and slowly heat the sensor, trying to run the bike at different temps. This worked well for finding intermittent sensors in some Ford and Mazda cars. No promises here, but it may help. Just don't get it so hot that things start to melt! Good luck Quote Link to comment Share on other sites More sharing options...
biffsgasgas Posted May 14, 2014 Report Share Posted May 14, 2014 Mark, Have you been in touch with the locals that I passed your way? Have you received your flywheel puller yet? Another way i have found a faulty sensor on one of my mazda's was to ice pack it. If it runs longer then you have probably found the root cause. Keyboard compressed air can cool down the stator through the flywheel btw... Thats_a_five knows what he is talking about. Found that Ford and Mazda use the same cam sensor for certain products. --Biff 1 Quote Link to comment Share on other sites More sharing options...
bigmark1972 Posted May 15, 2014 Author Report Share Posted May 15, 2014 (edited) BIff, Yeah I did call Scott and we talked for a bit, nice guy. I was going to have him measure his stator values but after getting input from Splat Shop decided to look at my key first. I have more evidence it could be the key (or timing) further down. According to Ryan my puller is on the way I expect it tomorrow. I did a little investigating tonight and found some damage to the spark lead where it had been rubbing on the frame and rerouted it (will replace it) just in case even it could have been grounding on me. I can not believe I did not do this sooner but I closed up the pole barn and turned off the lights and kicked it over. It absolutely has a spark (a lil blue one) and it is consistent. I'm used to Japanese motocross bikes with their easy to see monster huge sparks. I tried to start it and it looked to me like it was running backwards (it only runs a second or less if it starts). I got someone else to watch it for me and they also agreed it seems like it does not know what direction to run in.. AFAIK this definitely points to a timing issue... I'm hoping to find a sheared key or possibly the stator has come lose and lost it's timing under the flywheel. Will report back when I get the puller and have a look. CMON UPS.... Edited May 15, 2014 by bigmark1972 Quote Link to comment Share on other sites More sharing options...
biffsgasgas Posted May 15, 2014 Report Share Posted May 15, 2014 Well there was a recent thread in GASGAS where a weak coil caused a bike to run backward for a few moments as well. If you still have a 12 v MX bike around and you are good with some jumpers you might want to try that as well. It had a bunch of us baffled but it was a very similar issue. If that happens to be it.... I blame "Polar Vortex".... --Biff Quote Link to comment Share on other sites More sharing options...
bigmark1972 Posted May 15, 2014 Author Report Share Posted May 15, 2014 (edited) SOAB... I got my puller today and had a look. No sheared key, no lose stator, still spot on factory timing mark. I'm not sure what to think at this point, If I have a consistent spark the stator has to be OK I would assume? I suppose the coil could be weak. I still think it's ignition related might be some weird issue. I got with Splatshop and will get a Stator/CDI/new plug cap and wire on the way. If it ends up my stator is good I'll just sit on it. I love this bike and will probably have it for a long time... But if it keeps breaking on me I will have to sell it and buy a Honda / Mont Edited May 15, 2014 by bigmark1972 Quote Link to comment Share on other sites More sharing options...
copemech Posted May 16, 2014 Report Share Posted May 16, 2014 SOAB... I got my puller today and had a look. No sheared key, no lose stator, still spot on factory timing mark. I'm not sure what to think at this point, If I have a consistent spark the stator has to be OK I would assume? I suppose the coil could be weak. I still think it's ignition related might be some weird issue. I got with Splatshop and will get a Stator/CDI/new plug cap and wire on the way. If it ends up my stator is good I'll just sit on it. I love this bike and will probably have it for a long time... But if it keeps breaking on me I will have to sell it and buy a Honda / Mont Yea, well I never bought one of them when I found out about $600 fuel pumps! You seem to have a decent grip on things so you will get it squared away. Keep us posted! Quote Link to comment Share on other sites More sharing options...
thats_a_five Posted May 16, 2014 Report Share Posted May 16, 2014 (edited) Mark, I have a couple ideas for you. This will be easier with a helper. Reassemble the flywheel, etc, leaving the plastic cover off and the spark plug out. Make a socket drive that you can chuck into an electric drill or even a rattle gun. Click the bike into gear and give the crank a spin with the drill and watch the back tire to be sure it is turning forward. If not, reverse the drill motor direction so you know you are spinning the motor in the right direction. With that setup you can crank the motor continuously which is much better than the kick starter. Then click the transmission into neutral. With fuel turned off, and in a darkened area, attach the plug to the wire and clamp the plug to ground it so you can view the spark and not have to hold it in your hand. Then crank the engine with the drill motor and look for consistent spark. With the plug out, the engine should spin easily and the spark should be equally timed. Then take a hair dryer or heat gun on low to medium heat and while one person is spinning the motor, direct the heat behind the flywheel toward the stator / hall effect sensor. As things heat up, watch the spark. If it cuts on or off, you have found the fault. If not, move up along the wires to the coil, heating as you go. Go all the way to the plug if you have to. If the spark cuts on or off, you have found the fault. If it sparks consistently, then try freezing things by shooting Freon on R12 onto each of the electronic items one at a time just like you did with the heat. At some temp, an intermittent part will fail and the spark will stop. This is why you want to direct the heat and cooling to only one item at a time. You could also do this with the spark plug installed and the fuel on. This will require a stronger drill or rattle gun to spin the motor against the compression stokes. Just be ready to pull the drive off the crank bolt if the bike starts. Then if it does continue to run, continue the heating / cooling until it quits. Good luck and keep us posted. Bill Edited May 16, 2014 by thats_a_five Quote Link to comment Share on other sites More sharing options...
jfc Posted May 16, 2014 Report Share Posted May 16, 2014 Just a quick note, have you replaced the damaged HT lead (spark plug lead) if it has cut into the lead and the conductor is damaged you could get a week spark that will not spark when under compresson. Quote Link to comment Share on other sites More sharing options...
bigmark1972 Posted May 16, 2014 Author Report Share Posted May 16, 2014 (edited) Just a quick note, have you replaced the damaged HT lead (spark plug lead) if it has cut into the lead and the conductor is damaged you could get a week spark that will not spark when under compresson. Not yet, but I will soon. New one is on the way, also a stator and CDI from SplatShop. Tired of messing around with this now ignition should be covered. Edited May 16, 2014 by bigmark1972 Quote Link to comment Share on other sites More sharing options...
biffsgasgas Posted May 17, 2014 Report Share Posted May 17, 2014 mmmmm dont get discouraged. These are simple machines with complicated issues. If you dont get a ride this week to our local event i am willing to show up next weekend. It says something that you have been over the bars laughing all the way. Again if you have a coil from an MX try that. Got to be honest that i am 100% biased regarding the bike brand so dont take that as an insult. Its mainly due to my wardrobe and hascienda decoration.... that would all need to be changend. --Biff Ps. Hitch a ride if you can. We will find you an event to particpate if you head slightly east. Quote Link to comment Share on other sites More sharing options...
thats_a_five Posted May 23, 2014 Report Share Posted May 23, 2014 Mark, any updates on this? Quote Link to comment Share on other sites More sharing options...
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