75 CB360 - bad omen "yatagarasu" build

adventurco

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Pretty sure float height on the 360 is somewhere between 19-21 mm. 25 mm would lean it out not enrichen.
 

MiniatureNinja

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Re: 75 CB360 - bad omen "yatagarasu" build

advCo said:
Pretty sure float height on the 360 is somewhere between 19-21 mm. 25 mm would lean it out not enrichen.
Ok so off the carbs come to change float high to 21mm, but again... that probably won't fix it.

Bike doesn't behave rich, it has plenty of power. But it doesnt need choke at all to start (then again it's hot as fuck here in fire central northern california)
 

crazypj

Split personality, I fake being smart
You measured float height wrong if you got 25mm, I set them to 21mm. Original points shouldn't be a problem, they are good to at least 10,500rpm. Battery sounds good @13.6 v, what was it showing at idle? Did you check pilot jets? They are under flat slot plug to side of primary and secondary main jets
 

MiniatureNinja

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Re: 75 CB360 - bad omen "yatagarasu" build

Pilot jets good. Measured like the manual says, vertical body and a micrometer. Just pulled them to check again and sure enough 25mm. I'll set them to 21


Also, plugs look like this, wet... oil? Not a spec of smoke comes out of the pipe... so I dont know what to make of this
 

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crazypj

Split personality, I fake being smart
Don't know3 where you saw how to measure but that's wrong. Carbs inverted, tilt to about 70 degrees so arm is just contacting spring loaded shut off valve. Measure from gasket face to highest point of float. Service manuals always show carbs completely inverted but that is only to make the pictures easier to fit into the space available. Here's a quick pic of carbs I got Saturday, level is way too low
 

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MiniatureNinja

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Re: 75 CB360 - bad omen "yatagarasu" build

Ok so the manual says to make the throat vertical. I then watched a few videos and read that the carbs need to be tilted. I did it the way you show in your picture

Carbs are sorted so I'm just trying to figure out the rest. I'm hoping the valve steam seals aren't leaking, or the rings aren't bypassing oil, because to me that plug looks pretty bad
 

crazypj

Split personality, I fake being smart
If your getting 25mm at that angle, the only thing I can think of is the retainer screw came out and valve seat has moved. I've never seen or heard of it or had it happen but anything is possible
 

cb360j

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crazypj said:
Don't know3 where you saw how to measure but that's wrong. Carbs inverted, tilt to about 70 degrees so arm is just contacting spring loaded shut off valve. Measure from gasket face to highest point of float. Service manuals always show carbs completely inverted but that is only to make the pictures easier to fit into the space available. Here's a quick pic of carbs I got Saturday, level is way too low

Do these happen to be my dilapidated carbs? haha
 

irk miller

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crazypj said:
If your getting 25mm at that angle, the only thing I can think of is the retainer screw came out and valve seat has moved. I've never seen or heard of it or had it happen but anything is possible
Or the floats are upside down?
 

crazypj

Split personality, I fake being smart
cb360j said:
Do these happen to be my dilapidated carbs? haha
Uuhmmmm,maybe, if your Shawn ;) Not having 'screen name' with carbs makes it 'interesting' trying to communicate. Not a problem when I only have one every two~three months but 3 in a week confuses the hell out of me ;D
 

cb360j

Member
crazypj said:
Uuhmmmm,maybe, if your Shawn ;) Not having 'screen name' with carbs makes it 'interesting' trying to communicate. Not a problem when I only have one every two~three months but 3 in a week confuses the hell out of me ;D

Haha nope I’m Jared
 

Cursh

Loves Stock Airboxes
is 21mm float height for 378 only or also factory displacement? (sorry to but in here)


I think I set mine to 19.5 (from the manual)


(I know we've moved past float height for ninja, but I'm just trying to get my knowledge on)
 

crazypj

Split personality, I fake being smart
21mm for all 360's using E10 plus it works fine even if you can get non-ethanol
 

MiniatureNinja

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SPEAKING OF FUEL
I realize some of my problems - my initial 2 tank fill ups were with the gas we were using on the LS race bike - a 50/50 blend of 104 leaded and 89 regular

not sure if that is gonna have any downsides, but it wasn't burning like it should, and was also using too cold of plugs, so I put the proper plugs in, regular gas and she's doing MUCH better.

still slight misses if I am cruising around 4k rpm... not sure what that's about but a couple more tanks and i'll start doing plug chops and see what I can do with that

I also REALLY need to dynamically time the bike, and am waiting on a center stand from eBay to come in the post
 

teazer

Active Member
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When we ran our CB160 race bikes on the dyno we got slightly more power - consistently - with 89 octane street gas than we got with C12 race gas. If the motor doesn't have a ton of compression, use the lowest octane gas that it will run without pinging.
 

crazypj

Split personality, I fake being smart
If you do a compression check I would expect you to get around 200~220 PSI. Surprisingly, with GS850 pistons the combustion chamber shape seems pretty good so 89~91 octane works best. I've even used 87, doesn't seem to mind although I think my exhaust system helps as it's lon. Not sure how much lead is in 104 octane but lead does foul plugs and rot out exhaust systems.
 

MiniatureNinja

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so my K&N filters keep drying out in the sun. like I'll park for a day while at work and come out and the filters are grey and dry.

that's not good

would someone tell me about the UNI UP-6200 filters? are they good and will they work well with my setup?
 

irk miller

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I ran them on my 378. They were great, though maybe a little rich on the bottom end. Hard to say, since my memory is shit and the bike is sold. Also had a "desert sled" style exhaust, so there were variables not common.
 

MiniatureNinja

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Re: 75 CB360 - bad omen "yatagarasu" build

Found a brass pipe nipple, seams the right diameter to slip over the kicker if I chop the end nub off. Couple of fancy holes and drill and tap the end of the kick lever for a retaining bolt should be a nice touch
 

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yellowheader

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Hi Ninja, I've read your whole build thread and it's great. You've got some really experienced people giving you pointers, so hats off to them too. You've done some pretty cool stuff with that 360. I'm doing my first build on a CJ and I'm learning a lot from your thread. I'm staying with stock pistons and air boxes so I don't expect any big leaps in performance, but it will be a lot lighter (even without all the drilling you've done LOL). Looking forward to seeing your finished project!
 
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