lotty

Dear Cynic. Well, after all, I reckon the truth is we are all stumped. It's a come down for us all, perhaps. I mean, we just don't know. It's a leveler. Tough deep down. But....well.....er......at least we are 16 again haha x

Another update. I began to get my wiring head on by reading the manual and just looking at the loom and the components. What a mess. looming tape falling off, odd wires here n there, dirty connectors, ancient repairs, tangles, and all oily dirty, the type of grime where badness resides. So I set about cleaning all the wiring, venturing into places never ventured ever before since day zero. It looked a bit iffy here n there. Other owners had clearly left their home made repair hacks over 50 years. But gradually I found this component and that component and got my head into it. The big shock was under the seat where the main trunk of wires runs, it threads under the frame, ie right onto the top of the exhaust!, and under this frame cross member 8 of the 15 or so wires had melted into a solid block and many had corroded through........a real mess. Amazing anything had ever worked. I'd never noticed because It was just too dark and dirty under that bit. So I had to chop that section out and rewire that 4 inch section. By this time my parts had arrived. I replaced the rectifier which was just a little one inch square bit of plastic which had 'blown', blistered open. I fitted a new battery. I used many new connectors. The whole thing started looking orderly and tidy, none of that grimy badness, just now happy goodness. Eventually it was time to turn on the ignition and see what didn't work, but it did work.....indicators, stop lamp, horn, and neutral light. Fantastic. At last some reward and a weight off me. Now there is just the head and tail light and however the battery gets charged. I realized this will need me to have the engine running, which means outside in the winter cold. I plan to try it, but if it needs some time on problems then I may have to wait till warmer weather. But for now I will take it outside and try the lights. One other thing i did discover: I knew the two-stroke oil tank was showing low in its little window, so I topped it up; then for some reason i decided to just have a quick look at the oil pump and so took the cover off. As soon as i did all the oil spilled out all over the floor in one big flood...a mug full. I cleaned the oil pump and casing dry and went to top up again so i could see the leak....BUT nothing, no leak, tank still full. Bone dry. Not a drip! I left it for two days and still the same. So I think it must only leak when the engine is running. Anyway, I have bought new oil pump oil seals and gaskets and this is next weeks job. Saved a fortune in beer haha

I was also awake, pottering, turning, thinking and wondering if a decompressor helps navigate a tricky bit of terrain like a rocky drop where much control and finness is desired and a decompressor could help by being able to keep the bike in low gear without having any power on or stalling. So it seems none of us win a warm feeling in the pit of our stomach....haha

Thanks NEO. that DVLA info is very helpful indeed, and that insurance sounds just right.

Thanks for that NEO. I myself can only think there must have been a good reason why the designers would have put in an extra spark plug hole, so it's still a bit of a mystery. For some reason i never ever have ridden a trials bike. I watched them a lot, but that riding never appealed to me, though that tv programme 'Junior Kickstart' presented by Peter Purves was very watchable. It seemed a very different skill, and they had a little lever on the handle bar to decompress, and i suppose the use of it would only be known to a trials bike rider. But maybe even a DT in certain situations could benefit from a decompressor. But I don't know. Doug

Its been a few years since i rode my DT 175 1974, but now I can't wait again. But things have changed a bit i gather, that I don't need to tax it and MOT it, but will need to insure it. Do I have to register the bike with dvla as historic? Can I get very low cost historic insurance as probably only do 100ish miles a year?

The top of my DT 175 cylinder head has a port for the spark plug going in vertically, but it also has another port going in at 45 degrees (blanked off with a bolt). The only thing I can think of is for a decompressor which if I remember rightly was to help kick over large engines, and I seem to remember as a young lad that some of the trials bikes had decompressors. So, what is that 45 degree 2nd port for, and how are decompressors used when riding trials bikes? The correct answer wins a good feeling in the pit of their stomach, haha. Doug

Just an update. I bought a bike stand, the scissor type, so can get the flywheel to eye height, sat on stool. Superb, on castors, too. I have forensically cleaned the whole thing. No I am psyching myself up for the light electrics. I'm rubbish at posting pictures, but this youtube is totally identical in EVERY way, though mine has an 18inch rear wheel and 21inch front; this one looks like they are both 18inch, but probably the photo, so may as well post it. This bike looks in good condition, but cannot be better than mine. You would struggle to find a square mm of rust anywhere, and it is ALL original totally. It runs totally wick, like this one. I can't wait. It's been six years since i last rode it. It has done 6.5k genuine miles (I had to change the original perished tyres). Ps, my headlight is cream, and my chain guards and back brake bar are orange.

Well, the fat lady sang, but she didn't make the grade. Carb kit came. New o-ring on main jet and spang into life on 2nd kick. It's been an ordeal.....for me....pushed and tested me. But at my age I've got used to how it can be. I am very grateful for the support here and rex's for the coils rewind. Life certainly throws 'em at a person. I'm drained, haha. Thanks everyone.

Just a quick post to put this thread to bed. So the stator got rewound, the three coils and all cleaned up and re-wired and tested. A superb job by Rexs Speed Shop. I also purchased a new old stock flywheel magneto ( My old flywheel was stamped F-140, as is this new one, which means, according to the manual, that my bike is a UK series DT175. If it wasn't UK series it would be a CT175 and be stamped F-130) because i needed a new advance/retard which sits in the bottom of the flywheel. I wired it up and put it all together. Very difficult as always to set the points because so awkward and at the highest point the contact gap can be seen but the adjustment screw can't be got to! Anyway, I took a stab at it and kicked over for a spark.........which I got.....hooray. So it should work, BUT, with the plug in I kicked it over and eventually determined that no fuel is getting through at all, so I am having to service the carb before I can start the engine. But it should work. The stator coils rewind and re-wire is a good job and i'm sure it is right, just like new and all tested with the results.

Thanks, just the advice i need to begin the journey. The magneto is coming tomorrow. I'll get it all working and get familiar with the wiring and then try what you wrote and post how it has gone or is going so far. A great little winter job. It's a superb bike, great nick, untouched. I'll get my girlfriend to work out how i can show photos of the bike.

My headlight and tail light bulbs blow within a minute. I don't know much, but do know some. It wasn't the earth. These two lights get their electricity straight from the magneto, not via the battery. So I reckon it is basically that the voltage regulator isn't working right, and that is what is blowing them. I think it is under the tank. I'm sorting a little problem with my magneto at the moment, so i know the lighting coils are good and so is the condenser, so i would like to just continue a bit further and get the headlight and tail light working. I suppose the best thing would be to replace the parts like the regulator and whatever. I wouldn't be able to test them, and i can't keep blowing bulbs to see. So, to do this job, what should I order? I'll try myself, for certain, but if anyone can help with some advice i would welcome that very much. Doug

Cheers pal. It's on its way. What a good do. I really appreciate your help. Nice one. It does pass quick. Was all chatting the other day at my daughter's. Age came up. I looked at her and casually said, 'Well you're knocking on a bit now. what are you, 34'. Her face. Stunned. First time she'd ever heard anything like that about her. She said 'Yes'. I said, so your are only five and a bit years off forty!'. Suddenly she was almost 40! Ha ha. I did use this to make an important point, saying 'If there is anything you want to do, do it, don't hang about'.

Hi NEO and Cynic. Yes, the advance and retard arm. That picture of it in the flywheel it right. Cynic, sorry i couldn't find the picture on fb......it's me, I'm hopeless. I need another advance and retard arm. At least i know what it is I'm seeking. Not going to be easy. If anyone knows of a possible one then please let me know. On my damaged one (beyond repair), on the arm was some black plastic which I reasoned was debris fallen from the plastic coating of the magnets, so that is something to keep an eye on...chunks fall off and into the mechanism and could have caused the damage. So thank you. The advance retard arm. And thank you for explaining the reason for it and how it works. PS. I used to have a 175 mx. Sold my AP50 and got the mx all ready for my 17th birthday. A superb bike. My 4 other mates all sold their mopeds and got MXs. We drilled an extra hole in the monoshock to get em a bit higher. They were great bikes. We'd all shoot off over Pendle Hill and stuff. Take our baffles out and blast round muddy fields firing mud all over eachother. Even in the snow going home from the factory, cars and buses skidding sideways, and we'd go back over the tops riding through drifts. Great days. Once again, thanks. Doug