disastrous '71 yamaha CT1 restore?

[south]

a good friend's elderly father gave me his old '71 yamaha ct1 175 enduro a few months ago, as it had been collecting dust since 1976!

i cleaned the carb and put a put in a keyster kit, sealed the tank, replaced all the corroded gaskets, added new bel-ray oil in the injector, and she fired up today! when the smoke cleared, she seemed to be running darned good...though only with the idle/air screw screwed all the way in.

i warmed her up, drove around the block a few times, and was having a quite a blast...then suddenly...SMOKE...tons of it...billowing gray out of the tail of the pipe and the pipe/engine connection.

she died, and though i was able to restart her, she smoked like crazy and runs like crap. the plug was pretty fouled...but a new plug didn't make a difference. :(

ps: i hadn't changed the transmission gear oil yet..i was waiting til i got her warmed up.
ps2: i didn't test the oil injector first.
ps3: my girlfriend claims to have heard a "squeal" come from the bike before it started smokin'.

what happened?
now what?

 

[Skookill]

Are you sure you got the carb totally clean, Jets and all, let me repeat Jets... Jets... Jets!!? All those little holes. My 70 AT1 125 ran like crap untill I cleaned the carb a couple times and really got into all the little spots. These old bikes get alot of "sludge" from the tanks and a clean carb can muck up pretty fast. With your air screw set as is , somethings not right w/ the carb. Should be about a turn & 1/2 or so. Also put a fuel filter in the line from the tank. Just a tiny bit of crud knocked loose from the tank when riding can clog up you carb and make it run poorly. Much improved with this done. With the amount of smoke your getting also could have blown a cranck shaft seal. They tend to dry up and crack when these bikes sit for that long without running. My 70 AT1 sat for 25 years and (Knock on wood) I am still running the orig. seals. Good news is you can still find them on EBAY and I have an engine seal kit ready to go when they fail. Cheap and still availible. Another thought, try running a tank of pre mix fuel, your injector could be wacked. I bypassed mine because it was leaking and just do the pre mix. 32-1. And good god man.... POST PICS!!!!

 

[sm7482]

mostlikley your suckin gear oil. or your injector is wack, how many miles on it? also your air fuel screw shouldn't be all the way in you might have an air leak. when screwed all the way in it shouldnt run at all. i say if the injector is fine disconect it turn over the engine try to get all the gas-oil mixture out of the bike then once all the injector oil/gas mixture is out of the crank cavity kik it over and suck in as much pure gas as possible but dont start it! then pull the head+cylinder off and take a peek at the gas and the color of it in the crank cavity. if your sucking tranny case oil the gas should be the same color as your tranny oil. also if your seals are hard if your lucky they might soften up a bit, if your lucky.

 

[julien_d]

Sounds like you lost the RH crank seal to me. I'd follow sm7482's advice there.

 

[snowcat]

Ct1

Sounds like you've blown the seal on the clutch side of the engine, that allows the gear oil into the cylinder and it will smoke like mad. Don't forget to do the seal on the other side as will ( mag side)

 

[pryor]

changing seals on a ct1 is real easy, you can still get the seals and flywheel puller at your yamaha dealer.