elsinore250 Posted October 2, 2013 Share Posted October 2, 2013 Hi there, I am brand new to this forum and could really use you fellas help. After wanting a DT 175 MX since I was an 11 year old boy growing up in Leeds, England (my 18 year old neighbor had one back in 1979). I finally found one a few miles up the road from where I now live in Atlanta, USA. Bike is not sparking from plug cap or ht lead. I pulled the ignition cover only to find the flywheel compartment one third full of two stroke oil. Is this usually the case with a DT that's been sat for 30 years? Bike had been stored in a covered shed. It was very dusty from storage. It does have some surface rust that wipes off easily with fine wire wool. Looks like the carb is also toast as the slide was so gunked up with old fuel it is stuck in the carb body. One more thing.... Can anybody recommend a good battery for this bike? Any help or advice would be sincerely appreciated. Cheers, Paul Link to comment Share on other sites More sharing options...
elsinore250 Posted October 2, 2013 Author Share Posted October 2, 2013 Here are a couple of pics of the bike as I found it. http://www.flickr.com/photos/24167983@N04/10046410224/lightbox/ http://www.flickr.com/photos/elsinore250/10046395224/lightbox/ http://www.flickr.com/photos/elsinore250/10046529013/lightbox/ http://www.flickr.com/photos/elsinore250/10046514683/lightbox/ http://www.flickr.com/photos/elsinore250/10046618533/lightbox/ http://www.flickr.com/photos/elsinore250/10046617243/lightbox/ Link to comment Share on other sites More sharing options...
Moderator Airhead Posted October 2, 2013 Moderator Share Posted October 2, 2013 Greetings Paul so then, your bike is a DT175E or F in the USA, much the same as our UK DTMX's with a few differences I'll post an ignition fault find this evening...There should be no oil in the magneto casings. New here? we have a new members section where you can post a little intro Link to comment Share on other sites More sharing options...
elsinore250 Posted October 2, 2013 Author Share Posted October 2, 2013 Airhead, thanks for getting back to me. Bike was actually manufactured in 6/79. I believe that makes it an F model. Electrics are not my strong point (especially anything with lights). Same thing goes for oil injection. Do you think the 2 stroke oil has seeped through bad crank case seals? I have never really done much messing with road/trail bikes only vintage/evo MX and Trials bikes. Very excited to get started on the DT. I am actually going to use it to knock around on weekends and evenings. Thanks again, Paul Link to comment Share on other sites More sharing options...
dt502001 Posted October 2, 2013 Share Posted October 2, 2013 Hey Paul the only way for 2x oil to get into the mag is from the crank seal,a bike of the vintage should have the crank seals replaced as by now the will have dried up and will blow the motor if they suck air. You will need a puller to remove the flywheel. 20-30 bucks tops.to replace the seal on that side. As for the carb soak it in desiel for a few days and see if the slde will come free. Link to comment Share on other sites More sharing options...
elsinore250 Posted October 2, 2013 Author Share Posted October 2, 2013 Thanks for the diesel fuel tip. Carb cleaner didn't do anything to help. I first noticed the oil when I pulled the plug and kicked it over to check for a spark. I was thinking maybe the oil would have helped preserve the seals. I have got away with it with many of the other vintage bikes I have messed with. Do you guys think I am going to have to switch out the clutch side crank seal? Thanks again Link to comment Share on other sites More sharing options...
elsinore250 Posted October 2, 2013 Author Share Posted October 2, 2013 Should I buy a Yuasa battery or?? Link to comment Share on other sites More sharing options...
blackhat250 Posted October 2, 2013 Share Posted October 2, 2013 Aye elsinore "[ honda yeh] of a district in Calafornia, ? Anyway boiling water will free slide as the alloy expands different rate from slide,, Link to comment Share on other sites More sharing options...
blackhat250 Posted October 2, 2013 Share Posted October 2, 2013 If the clutch side is goosed it will suck gear oil. white smoke ,, . i would go gell battery nowadays , Motabatt Link to comment Share on other sites More sharing options...
elsinore250 Posted October 2, 2013 Author Share Posted October 2, 2013 Thanks blackhat250. You got it on the Honda thing, love 79 & 80 Red Rockets. I will give the hot water idea a try. Thanks for recommending battery type. Is the auto lube system likely to need a lot doing to it? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted October 2, 2013 Moderator Share Posted October 2, 2013 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...
elsinore250 Posted October 2, 2013 Author Share Posted October 2, 2013 Airhead, thanks for all the electrical info. I will let you know how I go on after I get into it. Link to comment Share on other sites More sharing options...
elsinore250 Posted October 23, 2013 Author Share Posted October 23, 2013 Got the bike sparking, freed up the carb. Had to remove the flywheel to replace the crank seal. Timing is not my strong point. Just ordered the tool on the following link. Will it enable me to correctly time my bike or do I need a timing light? Please see the attched link showing the marking on my flywheel and case before I pulled it. Can somebody please explain exactly what I need to do. Sorry for sounding like a muppet, like I said timing is not my strong point! Ta very much for any help offered. http://www.flickr.com/photos/elsinore250/10444173093/ http://www.flickr.com/photos/elsinore250/10444128476/ Link to comment Share on other sites More sharing options...
Moderator Airhead Posted October 23, 2013 Moderator Share Posted October 23, 2013 Hi Paul It looks to me like your timing is not adjustable because all you have is two countersunk holes for the screw...NOT screws and a slotted hole. If it isnt adjustable then it must be timed right...right? Link to comment Share on other sites More sharing options...
elsinore250 Posted October 23, 2013 Author Share Posted October 23, 2013 Correct Airhead. The counter sink scews just tighten up. No option to move the backing plate. Do I have to position the piston before I tighten the screws or won't that make any difference? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted October 23, 2013 Moderator Share Posted October 23, 2013 It will make no difference Paul. What is important though is that you tighten the flywheel retaining nut to the specified torque, this meams getting a good hold on the flywheel...you wont do it by hand! I use a chain type filter wrench and a fabric backed rubber strip cut from industrial work gloves. Link to comment Share on other sites More sharing options...
elsinore250 Posted October 24, 2013 Author Share Posted October 24, 2013 Airhead, thanks for all your advice. I actually spotted the chain filter wrench in a couple of your other posts. I went out and bought one this morning. Rotor is back on and correctly torqued @ 39.5 ft/lbs and I have a lovely fat blue spark. Would you stick an 8 or 9 plug in it? The Bike will be used for short low speed 10 mile round trips and the odd light trail ride. Can't believe how many NOS bits are available and how cheap they are. I have removed, cleaned and greased/oiled just about every moving part on the this little bike. Absolutely loving it! Going to collect the fuel tank Friday afternoon (my pal has cleaned and sealed it). Looking forward to firing it up. Will let you know how it goes. Thanks again for all your help so far. Paul Link to comment Share on other sites More sharing options...
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