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02 Sep 2019
Your admin has not been on the site much as of late as my main computer apparently seized up :( I have had limited access, but will be back soon. Thanks. Mako

TOPIC: New Owner Greetings & PIC of bike

New Owner Greetings & PIC of bike 23 Jun 2019 22:45 #11

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I agree on draining autolube tank, filling with correct oil, bleed pump and then bleed line at the barrel. I'd also make sure throttle cable oil pump cable relationship is correct. They need to be or autolube pump will pump oil incorrectly. READ MANUAL ON THIS, there is also a tutorial on video that is informative on pump workings, and checking. THIS IS A 2 stroke, requires oil mixed in fuel by autolube pump, or pre-mixing oil with fuel. Thats a nice lo miler, you'll have tons of fun with.
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New Owner Greetings & PIC of bike 25 Jun 2019 14:01 #12

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Thanks for the input.

Drained gas. Pulled carb. Have a new battery. Will have key Friday. Thx for heads up on ebay key source, seller cyclekeysonline had it cut and shipped within a couple hours.

Carb bolts on one side, only had the lock washer. Weird I thought until I noticed the flat washer was inside the flange like this. Must have been running lean with an air leak? Hopefully didn't cause too much trouble.



Couple more pics of carb. Do I 'gotta' go deeper in carb right now, or can I spray carb cleaner where I see now and blast with a can of compressed air? I'd like to get a bit more familiar with it before I break something while fixing it.

The discolored tube in last pic.... does that just go down draft to nothing? It pulled up from the nether regions where I can't see. What tube can I replace with? There are 2 small tubes and 1 larger tube, not sure of size but seems it needs to be petrol safe and good with high heat.

Thanks for the tip on running 32:1 until I confirm oil is pumping. Best way to confirm that? Just look for oil to be lower after a tank of gas? Think I read something about watching the tube dribble oil. How much should dribble from the tip?

If I do pull the bowl either because you convince me too, or because I just can't help it I haaafta look.... am I in for a gasket for sure? please please tell me amazon prime will have it here in an hour...





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New Owner Greetings & PIC of bike 25 Jun 2019 15:35 #13

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Welcome & i'm not sure but if not mentioned already the most important Oring on the bike is the tiny one in the carb. If that doesn't have good tension when sliding the bowl back on then it'll leak & bypass the main jet acting like a giant size main jet. If it feels under tension then it'll be ok--you'll soon know if its not. Also if no key then simply unplug the ignition switch & away you go--simple--no battery needed at this point--just make sure you have the throttle slide back in right & can hear the throttle slide shutting right down or you'll be looking for a way to kill it. If air boot is off for the first star well you could just choke it to kill it with your hand. Shouldn't be necessary though, just scare tactics sorry. Number 5 in link below.
www.partzilla.com/catalog/yamaha/motorcycle/1972/ct2/carburetor
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Last Edit: by RT325.

New Owner Greetings & PIC of bike 25 Jun 2019 15:57 #14

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I'd open the carb to clean the inside and check on that o-ring, and make sure nothing is missing. I once had a bike that the PO was running without a main jet, so it's good to verify that everything is there. Though from the condition of your bike I'd imagine everything is there, then again that out of place washer...maybe that's what got it parked. They are about as simple as they get and you won't get into trouble.

The discolored tube is for excess gas overflow, which can happen on a cool day when you park the hot bike and engine heat radiates into the fuel and expands it. The tube just helps dump it on the ground instead of on the bike, not exactly environmentally friendly ;)

You won't for sure need a gasket if you open the bowl, ~75% of the time I've been able to use the original.

While you're at it with the carb off, it's worthwhile to replace the carb to intake spacer o-ring, because if you don't you'll be tempted to overtighten it to achieve a good seal, and it's possible to get it too tight, which warps the carb and may cause the slide to stick.
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1972 Yamaha CT2 175
1972 Yamaha RT2 360
1972 Suzuki TS 185 Sierra
1995 Suzuki DR 350

New Owner Greetings & PIC of bike 25 Jun 2019 18:38 #15

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www.partzilla.com/catalog/yamaha/motorcycle/1972/ct2/carburetor

When I rebuild a carb, I replace the following from the diagram:
#3 needle (inlet) valve washer
#5 all important O-ring
#7 main jet carrier gasket
#11 bowl gasket
#18 gasket inside cap
#35 manifold O-ring
#36vent pipe
#37 vent pipe
#22 rubber cap
Check numbers on #1 & #6, the pilot jet (No. 25) and main jet (No. 200) respectively to see that they are Mikuni & standard size

Do you have to? No. But I just do it. It's been 40 years and perhaps several PO's. But yours may be in much better shape.

Open and disassemble the carb, soak it in Berryman's, and blow out all the passageways with compressed air. If you don't trust your memory or mechanical abilities, take a bunch of digital pictures before and as you take it apart. Might help when putting it back together. Don't force anything, and ask here if you are unsure.

I taught school for 28 years; the only dumb question is the one you don't ask.

Edit: Oh, and count the number of turns in the air screw (#26) and the idle screw (#24) from where you found them to all-the-way-in so that you can start again with them in the right places.

You can do this; we can help.
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Last Edit: by Mothersbaugh.

New Owner Greetings & PIC of bike 26 Jun 2019 00:55 #16

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Greetings from the UK. Nice find!

If no-one's mentioned it already, I'd fit a voltage regulator (6v don't forget) - this might save you a lot of headaches with blown bulbs. I'm not clever enough to explain why, but MarkT has posted at least one detailed explanation on the forum and you could search for that if you're interested.

Whilst I'm too lazy to post a link to Mark's post(!), I have attached below a link to the relevant document in the Tech section.

yamaha-enduros.com/index.php/workshop/se...e-voltage-regulators

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New Owner Greetings & PIC of bike 26 Jun 2019 07:35 #17

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Ok fellers - THANK YOU for the input help encouragement.

Pulled bowl off gasket is okay for now, float looks buttery.

I’m going to rebuild carb exactly as @Mothersbaugh suggested. That post is just too good. But first I’m gonna fire it up today. I think :)

Premix ign pulled airbox palm plug eject access at the ready then just pure glory. I think. Plan anyway.

Blasting carb first. Question about this:

Mothersbaugh wrote:
Edit: Oh, and count the number of turns in the air screw (#26) and the idle screw (#24) from where you found them to all-the-way-in so that you can start again with them in the right places.

You can do this; we can help.


5 1/4 big 3/4 little. But I don’t trust them because of the air leak from washer. Is there a default number of turns maybe more trustable?

I’ll capture vid of first kick :) hopefully glory shines through. Brap braaaap.

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New Owner Greetings & PIC of bike 26 Jun 2019 08:01 #18

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5 1/4 big 3/4 little.

Little is the air screw; start at 1.5 turns out on it. Big is the idle; take a peak in the inlet orifice to the carb, and if 5 gives you about a 1/8" gap you could stick a 1/8" drill bit in between the cutaway and the inlet floor, that would be good for starters. Might be too much, might be too little, but once it fires and starts to run, adjust it with the screwdriver you will have standing by in your pocket.
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New Owner Greetings & PIC of bike 26 Jun 2019 10:02 #19

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okay guys... first hurdle. no braaap.

new pre-mix gas, carb all cleaned up and hooked up. tried first just removing contact plate from ign, wasn't sure on the advice to just unplug ignition? looks like a good opportunity to clean contacts anyway.



kicked over, it did not sound like spark at all. so i hotwired with my daughters hair band in the #1 key position.



nothing. compression feels good. tried with battery in and battery out. turns out the battery i ordered was wrong one, so i'll have new correct one on monday. orig battery only charges to 3.5v think it has dead cell. but tried it installed anyway, not sure if running without battery, just leave positive hanging, or if it needs to be connected?

pulled the plug it has gas on it. i blew the gas off plug, grounded it and kicked with plug out to clear fuel and also check spark. i don't see any spark at all.

how to chase spark?

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New Owner Greetings & PIC of bike 26 Jun 2019 11:03 #20

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Baaah... ignore my chase spark thing. I'm learning here... first lesson is to listen to those with experience. when I sunk throttle piston into carb, it was super smooth and I paid attention not to go ape chit tightening down carb flange, thought I went just snug, but I didn't check throttle inside like I shoulda. Sure enough, the throttle sleeve was stuck up WOT. backed off bolts to almost strangely loose and throttle piston up and down good. Guess need to use some locktite for those bolts and just barely get a seal with o-ring?

Bike fired up. It pissed out a handful of oil at the exhaust flange on head and smoked quite a bit, but settled down. Sounds pretty good, responds well. Won't stay idle. I suspect throttle was adjusted with the air leak and I need to open up throttle a bit. POs... gotta love em, but they are the path so need to learn to deal with 'em :)

Any suggestions on adjusting throttle and the two screws (in what order and what to listen for or what RPM idle?)

I'll post a vid in a bit...

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