Brian Russell Posted November 10, 2011 Share Posted November 10, 2011 Hi there hope this is in the correct section of the site to put this... Having a nightmare trying to get to the root cause of why this bike will not start and needing a point in the right direction from someone to establish what to try next… It's been sitting in the garage and I have taken a notion to get it back on the road. To give a brief history the Bike is a 1985 DT125LC with 1 previous owner (I bought it from the previous owner in 1986 and I have owned it since then) that has covered just under 7K miles and has been unused and kept in the garage unmoved other than the occasional push about to get to something in the garage since circa 1988, it was stripped down in 1986 and rebuilt as a winter project as the previous owner had hand painted it completely black with skull and cross bones etc… it was returned to it's natural colour of red, a new loom fitted, rear wheel re-spoked, new battery, throttle cable, brake pads, spark plug etc… I would say I used it for a year or so with no problems and it's been in the garage at home since. It was running when left in the garage way back then. What I have changed/done to date over the last couple of days is as below and have the original Haynes workshop manual that I bought in 86' when fixing it up then that I have been using for reference to now… it won't kick or bump start; 1. New battery fitted. 2. Drained old fuel from tank and carburettor and replaced with new. 3. New spark plug BR8ES fitted which is giving a decent spark, also have double checked the gap on the old one which was also giving a spark and was tried originally etc… (wet with fuel after kicking) 4. Checked compression which is sitting at 135 Psi. 5. Removed cleaned and re-fitted the reed valve assembly which was in very good undamaged or fouled condition, gave a good clean anyway and put back together ensuring thread lock was used and gasket seal applied. The YEIS reservoir was clear of anything... 6. Removed cleaned and re-fitted the carburettor. Floats fine etc… cleaned the jet needle using fingers and petrol which is now sparkling with the inside of the carb clean. Petrol was allowed to flush through it to ensure clean. 7. Removed cleaned and re-fitted the air cleaner element which really was spotless anyway, cleaned that with petrol. Checked for any blockages between air element and carb with it being blockage free. What I did find was that the duct 34X-14437-00 that sits above the sponge air element that sits between that and the the outer cap was missing. It ran before without that so at this point putting that to one side. Not done but contemplating/planning it... 1. Remove exhaust and clean both sections internally with caustic soda to ensure no blockages, original full system still on the bike so would like to try and keep that rather than fit an after market system… have not removed yet as the screws/bolts were rusted, they been soaked with WD40 before I even contemplate that incase break something which I know I would regret. The bike other than the re-spray and new wiring back in 86' is essentially 100% in original state. 2. Opening up the YPVS to see what it's set at and if clean… have never ever been in there but the bike when used always easily went up to and I believe beyond the 80mph shown on the clock. It definitely hit the 80mph on the clock. 3. Check that the oil pump junction box cable is ok, the old plug was a nice colour so doubtful it's that but... I am presently going to double check the carb settings incase something there is out but I would have hoped it would have at least at this point given some indication about starting. It gives the normal sound when just kicking but nothing to indicate that it wants to burst into life. Hopefully someone can come back and give me a pointer on what to try next… I was going to take the throttle cable off and replace that and possibly the the twistgrip as well as when twisted it is not keen to return quickly. When twisted by hand back and forth the twist grip and cables appear to work fine so other than me being paranoid that is not really going to be an issue but I will be checking the oil pump cable end as above... Hope to hear from someone... Cheers, Brian. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted November 10, 2011 Moderator Share Posted November 10, 2011 After standing for 24 years my bet is the crank seals have perished. TBH as will a lot of the other seals too. Try giving the inside of the flywheel cover a drenching in wd, that may help get her running after a fashion if it is the seals, Link to comment Share on other sites More sharing options...
leightonbike121 Posted November 10, 2011 Share Posted November 10, 2011 hi,is the spark plug getting wet? if its dry it is going to be a fuel problem,possibly the crankseals as cynic has suggested.if the plug is dry,try priming it by pouring a little fuel into the spark plug hole (5ml-ish),i would think that it would at least fire.also;try removing the rubber air filter tube at the clamp at the rear of the carb,block the air intake on the carb completely with your hand/fingers or rag etc,hold the throttle open & kick it over a couple of times,if the fuel system is ok-ish your hand/fingers or rag should be soaked in fuel......hope this has helped Link to comment Share on other sites More sharing options...
Brian Russell Posted November 11, 2011 Author Share Posted November 11, 2011 Cynic and Leightonbike121 many thanks for coming back yesterday with suggestions and pointers, replied to each of you guys with PM's but neither has overcame the starting problem, even just to initially get it into life so that it can at least be seen running… have tried Cynics suggestion last night and this morning again with a new plug with no change, thanks for the try it straight after the WD40 is sprayed reminder getting that use to spraying to ease of things and protect without thinking about sealing there and then… any further ideas/suggestions out there before start getting deeper into it over the weekend which will undoubtably unless a simple solution is found end up with the bike getting stripped down which whilst not being a bad thing given the time it has sat and a very good refresher on these engines for me personally it would be nice to hear it going before deciding whether to head down that road or not. Cheers, Brian. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted November 11, 2011 Moderator Share Posted November 11, 2011 So you are certain the carb is clean and the choke is working? So have fuel, and spark. This is an oldskool trick i have used in the past that may work although it normally costs a bit of skin. Get a plug you KNOW is good, gap it clean it then heat the fkr with a blowlamp till its proper hot, then stick it in the motor quick as you can and try and start it. It should give you a few clean kicks before she floods. Have you tried bumping? I'm still leaning towards the seals, one of the symptoms is being hard/impossible to start, but word of warning she may rev her spots of if she does run. Due to being lean due to the seals so be prepared. Esp if you try bump starting. Link to comment Share on other sites More sharing options...
leightonbike121 Posted November 11, 2011 Share Posted November 11, 2011 once again,i agree with cynic regarding warming the plug,i also seem to remember that putting a little pencil lead on the plug was used to aid the spark ( havnt heard that one suggested for quite a while tho....old school) did you know that the spark plug may be sparking when you check it but it may not spark when under compression? seals look like prime suspect tho,as previously suggested by cynic.i picked up a 1971 ts125 duster a while ago,been stood for god knows how many years,was completely covered in ivy,leaning against a shed,you couldnt even see the bike, i got it home & had it running in less than an hour,so,live in hope & if all else fails,rebuild the motor,not too difficult & you couldnt put a price on the satisfaction when it eventually bursts into life. Link to comment Share on other sites More sharing options...
Brian Russell Posted November 13, 2011 Author Share Posted November 13, 2011 Well guys here's an update, did a few more things earlier today in the order below... 1. Completely opened up the throttle cable and oil pump cable junction box giving it a good clean along with removing and re-fitting the throttle cable (same cables used, none renewed), still not 100% happy with it but it's feeling a bit better than it was. The tension in there is just not correct, when you twist the throttle backwards and forwards by hand it all moves ok but there is not enough tension to the throttle cable from the oil and carb cables between them to simply pull the throttle cable back into position in the junction box bringing the twist grip back into a starting position. 2. The nuts at the exhaust after spraying and tapping away at this week were deemed ok to try and remove, came out a treat was just some surface rust down there, better are than sorry. The exhaust gasket definitely needs replaced, about 1/6th of the inner diameter is slightly damaged (squashed) so probably not a great seal. That's being ordered and the exhaust will be cleaned internally and the front pipe put back on for now then the tail pipe when all's ok... 3. Kicked it after the exhaust was taken off and it burst into life 1st kick, let it scream and I mean scream away for about 15-20 seconds then switched it off… Wishing had not now, would not kick start again after that neither did it fully bump start but when bumping it did a couple of times give a little burst and away it went but that lasted only a couple of seconds each time but definitely encouraging stuff. 4. Tried the heated plug as advised, no change… the spark is a good healthy one. What I plan on doing now is again tinkering about with the throttle from the twist grip back to the carb but need to get to a position where I'm happy with the workings of that junction box, at least it started and presumably now I have to assume maybe wrongly of course that in general the seals are ok given that it did start and appears willing to start, it's not been discounted as an issue though and will be checked sooner rather than later. That all said I really am thinking now it's a fuel problem but the plug is always wet when I take it out. It's always sat in a dry warmish garage along with a couple of other bikes that seem ok, took the old K reg Kawasaki GPX600R out of the same garage today which has also sat unused for a lengthy period of time with just trickle charging the battery the past week and that burst into life and went relatively ok, clutch cable was a bit squeaky at first and the front brake needed eased off as it had locked up but it went up and down the road fine after a bit of pushing about. Will keep posting how it goes, if can advise on anything to do please do guys it's very much appreciated and keeps me going in the correct direction. Link to comment Share on other sites More sharing options...
Brian Russell Posted November 14, 2011 Author Share Posted November 14, 2011 Ok guys tonights update as it stands just now after a quick tinker about... After taking the junction box apart again and the carb to change the carb cable settings the sliding movement is a great deal better than it was, still not where I want to be with it but it is better and bursting into life after each and every kick which is comforting though it is revving straight up to 8-9K with the twist grip untouched, going higher if twist slightly so plan on tinkering about with all this some more until I can get it as good as I believe I can, very sure now this is the root cause of the problem… still have those seals at the back of my mind though. Any thoughts please shout out… Link to comment Share on other sites More sharing options...
Moderator Cynic Posted November 14, 2011 Moderator Share Posted November 14, 2011 Now don't shoot me here, but it is possible to put the slide in incorrectly so it stops on the peg that aligns the slide in the carb. This will give around 2/3rds throttle. Link to comment Share on other sites More sharing options...
Brian Russell Posted November 14, 2011 Author Share Posted November 14, 2011 Never would shoot anyone that's helping … the throttle sleeve in the carb should be in there correctly with the slot sliding up and down the locating pin/bump, there is a circa10mm gap at the base on the air intake side that you can see through and it is going up and down easily when you twist the throttle and feels to be bottoming out inside the carb. Could see nothing in the Haynes workshop manual I have about this gap but I did see a old carb the same model on the web that showed this gap at the air intake side and fully closed at the reed side which is what I have here. Gonna nip off and have a look though… you never know. Link to comment Share on other sites More sharing options...
Brian Russell Posted November 14, 2011 Author Share Posted November 14, 2011 Cynic checked there and after originally getting what I had put above with the gap at the air intake side (the half moon on the sleeve base) and the other flat side bottoming out the sleeve was when put together earlier positioned correctly and moving freely but was sitting high and locked when I opened it up there which will explain why it was revving so high, it felt easy enough moving up and down by hand and was doing so using the throttle before fitting the carb back onto the bike… whilst giving it a gentle little tug to free it the the cable snapped , what I found however was a tiny indentation on the corner edge of the slot on the sleeve that has stuck on the locating pin when going up and down… never looked too much at the sleeve as it appeared to be sliding freely earlier but it has not been quite 100%. The smallest things… it's been smoothed down with wet and dry now. Ordering a new carb cable tomorrow but hopefully fingers crossed that's it solved. When I get that I'll post how that went. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted November 14, 2011 Moderator Share Posted November 14, 2011 that gap is the slide 'cutaway' all carbs have them but to different degrees some are big and some are small Link to comment Share on other sites More sharing options...
Brian Russell Posted November 21, 2011 Author Share Posted November 21, 2011 Well guys I got my grubby little paws on the new number 2 throttle cable tonight, fitted it all back together and hey presto we have a nicely running bike with a freely moving junction box inners, throttle and carb… the exhaust has already been given a clean up and a re-spray and out of necessity a new silencer was ordered last week that will hopefully be delivered this week so that can finish it off as far as getting her up and running goes. The inners of the original silencer that had been on from day one literally fell out the end like grains of sand when cleaning it up, apart from that it's all stayed in pretty good nick mostly thanks to it being sprayed liberally with WD40 and greased up years ago. A couple of bits like the carrier on the back have been sanded down and repainted (the TLC part) so when that's all done she can head off for an MoT then get tucked up safely into the garage awaiting a sunny day next year. Link to comment Share on other sites More sharing options...
Brian Russell Posted November 30, 2011 Author Share Posted November 30, 2011 Well that's her all sorted and tucked away in the garage again for a sunny day... http://imageshack.us/photo/my-images/9/20111128142004.jpg/ Link to comment Share on other sites More sharing options...
NE0 Posted December 2, 2011 Share Posted December 2, 2011 Well Done, brian. However, if you're tucking it away for the winter, may i suggest (if you've not done it already) you mentioned in the first post ............."new battery"! The least you can do is disconnect it, even better: keep it charged up every month...mark it on the calender otherwise come february it will get forgotten and die and you'll be paying out for another..... I'd also kick it over every 2 to 4 weeks otherwise you're going to be faced with every chance she won't start again! Afterall..............prevention is better than cure Link to comment Share on other sites More sharing options...
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