steve1979 Posted August 1, 2010 Report Share Posted August 1, 2010 (edited) Hi guy's, i'll try and keep this as short as possible. The bike which is a 2003 250 txt pro has been getting more difficult to start when warm after you have switched it off for a few minutes. Then on her last outing she just cut out altogether and after everyone there having ago at starting her the kick starter snapped off, in the middle of nowhere. Got a new kick start on and now she wont start at all even when cold. My checks so far are New plug New HT cap New HT lead cleaned carb thoroughly although it was spotless any way fuel flows freely from tank, so the breathers are fine. Looking at the spark it's not too strong looking but is blue, so i tested the resistance on the stator wires and got 100 ohms when it should be 99-99.9 and 20 ohms when it should be 26.1 on the blue wire's so i suspected the stator. A Friend has the same bike so yesterday we tested his wire's and got the same results and his bike runs great. So we put my CDI on his and his started and ran fine. We put his coil on mine and mine still wouldn't start. It did briefly start for a minute or so with my own parts and while it was warm we got 25 ohms at the blue wire's I tried every thing i could think of and nothing makes any difference, i did however get her to start today by heating the spark plug with a blow torch then quickly screwing it in getting burnt fingers in the process and she seemed to run okay, but as soon as you turn her off she wont start again. when she wont start after ALOT of kick starting the plug still seems dry. So where do i go from here, any suggestions apart from scrapping her lol Could the carb or the stator be faulty although they both seem fine, iv'e cleaned everything on the carb i thinks its probably cleaner than it was when it left the factory. There's no corrosion on any connectors at all so i can rule that out Stator rewind? New carb? New coil? All three... it starts getting expensive pretty quick Edited August 28, 2010 by steve1979 Quote Link to comment Share on other sites More sharing options...
tt5th Posted August 1, 2010 Report Share Posted August 1, 2010 I'd go with the stator based on that info. Quote Link to comment Share on other sites More sharing options...
steve1979 Posted August 1, 2010 Author Report Share Posted August 1, 2010 thanks for the reply tt5th, i'll try and get the stator rewound, i called motoplat on satarday but the fellow who deals with the stators is on holiday for 10 days so i'll try him again later according to there web page they deal with trials stators so that's prbably my best place to go, i did read on here to avoid west country windings and motoplat seem to have a fixed price, she's got the full lighting kit on her from new but i think i'm going to take all that off to simplify things. Quote Link to comment Share on other sites More sharing options...
jse Posted August 2, 2010 Report Share Posted August 2, 2010 (edited) Hi guy's, i'll try and keep this as short as possible. The bike which is a 2003 250 txt pro has been getting more difficult to start when warm after you have switched it off for a few minutes. Then on her last outing she just cut out altogether and after everyone there having ago at starting her the kick starter snapped off, in the middle of nowhere. Got a new kick start on and now she wont start at all even when cold. My checks so far are New plug New HT cap New HT lead cleaned carb thoroughly although it was spotless any way fuel flows freely from tank, so the breathers are fine. Looking at the spark it's not too strong looking but is blue, so i tested the resistance on the stator wires and got 100 ohms when it should be 99-99.9 and 20 ohms when it should be 26.1 on the blue wire's so i suspected the stator. A Friend has the same bike so yesterday we tested his wire's and got the same results and his bike runs great. So we put my CDI on his and his started and ran fine. We put his coil on mine and mine still wouldn't start. It did briefly start for a minute or so with my own parts and while it was warm we got 25 ohms at the blue wire's I tried every thing i could think of and nothing makes any difference, i did however get her to start today by heating the spark plug with a blow torch then quickly screwing it in getting burnt fingers in the process and she seemed to run okay, but as soon as you turn her off she wont start again. when she wont start after ALOT of kick starting the plug still seems dry. So where do i go from here, any suggestions apart from scrapping her lol Could the carb or the stator be faulty although they both seem fine, iv'e cleaned everything on the carb i thinks its probably cleaner than it was when it left the factory. There's no corrosion on any connectors at all so i can rule that out Stator rewind? New carb? New coil? All three... it starts getting expensive pretty quick In that the bike runs well when it runs, I probably rule out the carb as faulty. Have you looked at the killswitch as a possibility? You might want to check that by disconnecting it to see if that aids starting. I'd also take the stator off and throughly clean/sand the stator contact points where it meets the case. An NGK BPR5EIX plug at .024" takes less voltage to fire. I assuming you have used fresh premix after draining the tank/carb. Old fuel makes for hard starting. I'm not sure if you have the Kokusan V1 or the Ducati Digital V1, but both are good systems and generally don't degrade in performance (both were used in 03'). I'm assuming you've taken the flywheel off to check, so a sheared Woodruff key is not the problem. Jon Edited August 2, 2010 by JSE Quote Link to comment Share on other sites More sharing options...
steve1979 Posted August 2, 2010 Author Report Share Posted August 2, 2010 Hi Jon, yes i have new fresh fuel in. I have the multi function kill switch that does indicators lights horn etc but i have ordered a simple push button kill switch to do away with the lights etc but i took the one on at the moment apart and checked for corrosion but it all seemed fine i sprayed contact cleaner in anyway and blew compressed air into it. I have the Kokusan v1 system on mine i think she may be a 2002 sold in 2003 with 2003 graphics. I haven't taken the flywheel off yet although what paint i can see around the flywheel inside is quite flaky, i don't have a flywheel puller yet but i will order one tonight. My friend reckoned the fly wheel was still in the correct position by setting her to top dead center by using a probe in the plug hole and checking the position of the flywheel. And as he got the exact same ohms as me i assumed the stator was functioning properly although on the pick up i was only getting 20 ohms when cold but approx 25 when warm, but so was his. If i remove the flywheel or should i say when i remove the flywheel, will i need a new woodruff key and flywheel bolt also when putting the fly wheel back on after work has been done is it worthwhile heating the flywheel up in the oven a little to assist it going on the shaft better. I was going to order a either platinum or iridium plug too, i tried getting one here but no one stocked it. Thanks for your suggestions so far Jon Quote Link to comment Share on other sites More sharing options...
jse Posted August 2, 2010 Report Share Posted August 2, 2010 Hi Jon, yes i have new fresh fuel in. I have the multi function kill switch that does indicators lights horn etc but i have ordered a simple push button kill switch to do away with the lights etc but i took the one on at the moment apart and checked for corrosion but it all seemed fine i sprayed contact cleaner in anyway and blew compressed air into it. I have the Kokusan v1 system on mine i think she may be a 2002 sold in 2003 with 2003 graphics. I haven't taken the flywheel off yet although what paint i can see around the flywheel inside is quite flaky, i don't have a flywheel puller yet but i will order one tonight. My friend reckoned the fly wheel was still in the correct position by setting her to top dead center by using a probe in the plug hole and checking the position of the flywheel. And as he got the exact same ohms as me i assumed the stator was functioning properly although on the pick up i was only getting 20 ohms when cold but approx 25 when warm, but so was his. If i remove the flywheel or should i say when i remove the flywheel, will i need a new woodruff key and flywheel bolt also when putting the fly wheel back on after work has been done is it worthwhile heating the flywheel up in the oven a little to assist it going on the shaft better. I was going to order a either platinum or iridium plug too, i tried getting one here but no one stocked it. Thanks for your suggestions so far Jon Sometimes the multi-function switches are a weak spot in the electrics of off-road bikes as they are subject to a lot of moisture and grit, so that may be a contributing factor. Once in a while an electrical problem will be caused by a combination of several small problems and you need to trace all of them down. Since your bike starts/does not start, that a much bigger pain than if your bike would just plain not start at all. The not start at all syndrome is usually just one problem to trace down. The Kokusan V1 is a really good system and what I have on my 02 280 Pro and I don't remember hearing of a stator problem before, although there's always a first. It's not unusual for the flywheel key to shear on older bikes if the flywheel bolt has not been re-torqued. The huge number of heat cycles (in your case, almost 8 years worth) coupled with the heavy flywheel and shock loads a Trials bike engine encounters will loosen the hold the hub has on the crank stub over time. The "shear key" or Woodruff key does not hold the flywheel in alignment with the crank, it is only used to index the flywheel to the crank during assembly. If you could remove it after the bolt was torqued, the flywheel would still be held fast to the crank stub. When you get the flywheel off, you'll notice that the crank stub is tapered as is the flywheel hub and those tapers are ground at a slightly different angle from each other which results in them getting "stuck" when tightly pulled together, like with a bolt. That's why you need a flywheel "puller" to get them "unstuck" by pulling them apart. So, don't heat anything up when you put the flywheel back on, it's not only not necessary but counter-productive. The bolt will not need to be replaced but I like to put a little blue Loctite on the threads upon assembly. The NGK BPR5EIX is an Iridium plug and the best of all the plugs I've tested so far. Most shops don't stock a plug that "hot", a "5" as opposed to the normal "8" or "9" for most dirt bikes so I'm not surprized they had to order it. I think I've had the EIX in my Pro for over two years and I take it out and check it, no gap change so I put it back in and it's been perfect from 28 degrees at 12,000 ft altitude to 109 degrees at sea level, through rain, humidity even snow. I may put a new one in this year before I head up to Colorado but it will be out of mechanic's guilt, not necessity. Iridium plugs are designed to operate for 100,000 miles without replacement in a car. Jon Quote Link to comment Share on other sites More sharing options...
tltel Posted August 2, 2010 Report Share Posted August 2, 2010 Hi You said that the plug was dry after a lot of kicking, sounds like you are not getting any fuel in. have you checked compression or leaking gaskets, it could even be crank seals. Have you looked at the reeds(assuming they have reeds). To me it doesnt sound like elctrical. TLTEL Quote Link to comment Share on other sites More sharing options...
steve1979 Posted August 3, 2010 Author Report Share Posted August 3, 2010 Hi guy's, thanks so far. yes your right Jon, it would be better if it just did not start at all at least then it might have been solved easier. I'm retaking my bike back to my mate who has the same model that we tested the different components on, at the weekend, he also has the correct flywheel puller so we will take it off and have a look and see if that sheds any light this coming weekend. I'm really stumped though as to whether its fuel or spark, when i did get it started by heating the plug it was a bit lumpy as i eased of the choke, i had to fiddle the choke lever off and on to keep her running till she was warm enough to run with out, then i took her for a run around the field and i reckon she would have just kept running as long as i wanted once it was going, eventually i got off and just let her idle then after a minute or so she just petered out then would not restart again no matter how many kicks i gave it, i even try'd bumping her but nothing. Which makes me think surly if it was the carb it would not run at all. But then the same goes for the spark although by heating the plug is that somehow helping the spark. I'm no expert but the symptoms of her getting worse each time i was out kinda points to the stator to me but then i was getting the same ohms as my mates. From what i can see pointing a torch into the two holes on the flywheel and rotating it i cannot visually see any scorched or obvious defective parts on the copper windings. Perhaps when the flywheel is off it may reveal something. Quick question though, seeing as the flywheel and stator is coming off regardless would it be worth while changing the crank seal or should i just leave that alone and concentrate on getting her running again. Cheers guy's your comments are much appreciated Quote Link to comment Share on other sites More sharing options...
steve1979 Posted August 3, 2010 Author Report Share Posted August 3, 2010 (edited) Hi You said that the plug was dry after a lot of kicking, sounds like you are not getting any fuel in. have you checked compression or leaking gaskets, it could even be crank seals. Have you looked at the reeds(assuming they have reeds). To me it doesnt sound like elctrical. TLTEL Oh forgot to mention it got new reeds less than a year ago although i have had the reed block out and checked and they were still good. I do have a compresion gauge somewhere i will dig it out and do a proper check. Just noticed on the haven trials sport web page for parts it looks like the seal would have to go in by splitting the cases if so i wont go that far yet, Cheers Edited August 3, 2010 by steve1979 Quote Link to comment Share on other sites More sharing options...
steve1979 Posted August 4, 2010 Author Report Share Posted August 4, 2010 (edited) Okay, i did a compresion test and it came out okay, right at the top of the green bar. She was reading 148 psi so i'm guessing thats okay, i will post up my findings at the weekend to see what condition conponents are in behind the flywheel. Edited August 4, 2010 by steve1979 Quote Link to comment Share on other sites More sharing options...
jse Posted August 4, 2010 Report Share Posted August 4, 2010 Okay, i did a compresion test and it came out okay, right at the top of the green bar. She was reading 148 psi so i'm guessing thats okay, i will post up my findings at the weekend to see what condition conponents are in behind the flywheel. Fuel turned off, plug grounded away from the head, throttle wide open and several kicks in sequence? 148 seems a little low but not enough to cause the problems you describe I would imagine. On the subject of crank seals, you have two, inner and outer, on the alternator side as the transmission feeds oil to the crank bearings in the Pro, unlike any other two-stroke you are probably familiar with. Jon Quote Link to comment Share on other sites More sharing options...
steve1979 Posted August 5, 2010 Author Report Share Posted August 5, 2010 not quite, its an oldish compresion gauge and the type you have to push in place and hold so it's 2 man job, i held it and my dad kicked her over twice but i doubt he held the throttle open, i'll give it another go and see if we get a better reading. Iv'e been decribing the bike problems to various mechanics that work at the firm i work for and all them say iv'e done everything they would have done and have no suggestions. So if the flywheel being removed dosn't shine a light on anything i think my only option is then to have the stator rewound just to rule it out. After that i'm stumped Quote Link to comment Share on other sites More sharing options...
steve1979 Posted August 5, 2010 Author Report Share Posted August 5, 2010 Did a quick compresion test again on my own, wide open throttle / several kicks and got her at 165 psi. If i get her running again i'll treat her to new rings in the winter months Quote Link to comment Share on other sites More sharing options...
steve1979 Posted August 7, 2010 Author Report Share Posted August 7, 2010 Todays findings woodruff key was fine so timing's not the problem Stator looked okay and behind it was nice and shiney but i cleaned it anyway, still poor spark Swapped both little black boxes and still poor spark (one up at the headstock and the other screwed on to the radiator ) got the irridium plug put that in and still poor spark Done before but again swapped coil and still poor spark although both stators were getting the same ohms reading were going to swap stators tommorow I put the flywheel back on after cleaning behind the stator and torqued it up to 40nm but that seemed a bit weedy i would have expected alot more "heave" on the crankshaft bolt, could someone confirm the torque for that bolt please Thanks in advance Quote Link to comment Share on other sites More sharing options...
jse Posted August 7, 2010 Report Share Posted August 7, 2010 I put the flywheel back on after cleaning behind the stator and torqued it up to 40nm but that seemed a bit weedy i would have expected alot more "heave" on the crankshaft bolt, could someone confirm the torque for that bolt please Thanks in advance 40-42 Nm is the factory recommendation. Jon Quote Link to comment Share on other sites More sharing options...
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