1974 Yamaha dt250 Enduro

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I was gifted this bike in original state but has not been played since '86 and ORV since '88. Kick start still moves and there's surprisingly no leaks of fluids anywhere. My question is, what oils do I need to start getting it ready to be fired up again?!
Thanks
 
I'd throw some kind of lube in the spark plug holes before anything. Drain everything, fill fresh, check the wires for oxide, clean the carb out, and try to start it. If it worked when parked, really these are the only things that will prevent it from starting and running just like it did the day you parked it.
 
Check the specs for oil, as old as it is it probably calls for 30w. I helped a friend fix one of those once, but a 350 i think. It was 2cyl and syncing the carbs was a biznatch. I use Valvoline 10w30 4 stroke oil in all my small engines. Does its job and i get it cheap at the local farm and home store. Its good for wet clutches if that has one. We didnt have to rip the motor apart on the 350, just fix the carbs, hoses, and wires.
 
It is a two stroke so make sure the injector tank is full of two stroke oil. Access under seat.Gear box/clutch should take 30wt. oil. Haven't seen a set of thermal flow shocks in ages!
Enjoy the your new ride.
 
I LIKE these bikes, 2T is a bonus
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I love these bikes. I have two. These are the true apocalypse motorcycles. 10w30 in the crankcase. Any oil will work. Doesn't matter if it's wet clutch compatible. The wet part is what's important not the oil. I put 10w30 conventional in mine. I would premix the gas but wouldn't worry about anything in the spark plugs hole. They have oil injection but it was a ancient design and not a really good one due to it's hooked to the throttle. Alot if these siezed because if your flying down the highway let off the gas no more oil to a high revving engine.
I unhooked the oil injection blocked off the oil feed into the crankcase and mix the oil 32:1 using a semi synthetic two stroke TC rated oil. I very had my little Yammies for over 5 years and they are a barrel of fun because they so little and wicked.
Lots of fun. I get more comments on my Yanaha DT at bike week then $20,000 Harley's. I love it.
 
Another thing I can let mine sit for 6 moths to a year and it usually starts by second kick.
Super simple, reliable design. You can take the battery out and still runs. I leave my battery in so the power has a place to go but truly a apocalyptic motorcycle that will run on anything.
 
2 stroke injector oil in that tank on the side below the seat, ATF or a 30 wt HDEO or a MC 4 stroke oil oil in the transmission. The DTs are beautiful.
 
I had a DT250 back in the day. Even the same color! I would take the oil tank off and clean it, and possibly the gas tank and carb as well.
 
Love the old DTs. I had a 74 DT 360 in High School. At the time the local PD had officers riding the same bike. It was strange seeing them around town on bikes just like mine.
 
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Put new tires on it. Tires that old are blowouts waiting to happen and a blowout at speed is something you do not want to experience on a motorcycle.

Back in 1973 I bought a 1964 Yamaha 175 2 stroke. I did not trust the 2 cycle oil injector so I pulled it off and ran pre-mixed gas.
 
Clean the mice out of the airbox.

I always left the oil injection pump in place and the oil tank filled, mine never quit - but I always added a tablespoon of STP to the gas, just in case!
 
Blast from the past. I didn't have one but riding buddies had them from 125 to 360 and beat them mercilessly. True jack of all trades ride. The only thing that seemed to kill them was letting the 2 stroke oil tank run dry. Looks real stock except for the rear shock upgrade.
 
Those bikes had oil injection. Due to it's age, and unknown condition, I suggest pre-mixing the gas and oil at 40 to 1. The oil injection pump is very likely to NOT function (at least initially) due to congealed oil, air or a clog.

Use any quality two stroke oil designed for air cooled engines.

Also, many of those bikes had a unique electric start feature. They energized the engine's generator with battery power to directly turn the crankshaft over. There was no starter motor.

I can't recall if that particular year had that feature, but I think so.
 
Originally Posted By: AZjeff
Looks real stock except for the rear shock upgrade.


Mine had those shocks too. Those are probably original. They were designed to "look" like the more modern shocks with a separate nitrogen chamber to prevent oil foaming. The Yamaha versions simply had an oil reservoir that looked like something it wasn't. If I remember correctly, one can simply unscrew the cap on the reservoir and fill it with oil.
 
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Use premix to get it running, and then check that there oil coming from the pump at the carb. Crank oil seals could be a problem if it's been sitting...the left side will make it run lean, right side may make it burn gearbox oil.
 
My brother and cousins and I use to take my 175 Yamaha to some abandoned strip-mine and take turns trying to climb mountains. We sometimes had bull-rope strung down whatever mountain we were trying to climb with several people holding the top of the rope at the top of the mountain. If you did not make it all the way up the mountain you could grab onto the rope instead of falling back down the mountain. That bike took quite a beating tumbling down mountains that it could not get up.

I still remember the first time we took it to the strip-mine. One of my cousins rode it during his turn and did not come back when he should of. After a while we went looking for him. He was on foot and trying to climb up a mountain that the bike was stuck half-way up. I thought that I could take this either one of two ways. I could get mad because he dumped the bike, or I could shrug it off and not say anything and let everyone have fun riding the bike. I decided to shrug it off. We ended up taking that bike to those strip-mines many times over a couple of years and we had a lot of fun. We even took it there in the winter. Those that were not riding it would try to hit the cylinder on the bike with big snowballs. If you hit it the cylinder would shrink enough to grab the piston and stall the bike for a half minute or so.

To the original poster, one thing I remember about that bike is that it use to foul spark-plugs quit often, and then the Yamaha dealer suggested I try an iridium spark-plug. That iridium spark-plug was un-foulable. That plug ran for a couple of years and was still good and in the bike when I sold it years later.
 
Use 10w40 or 15w40 in the gear case. 10w30 can make the clutch slip. Type F ATF also works well, but I prefer a 10w40 or 15w40. I always use Shell Rottella.
The oil pump will likely be non functional to start with, if it works at all as others have mentioned. Personaly I would premix at 32:1 with Yamalube 2r or Honda HP2 and forget the oil injection all together. If you must use oil injection rebuild the pump. I believe the pump off a Yamaha Blaster is the same, but am not certain. Dont use a TCW3 marine oil in it!
 
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