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CB360 ongoing work

12040 Views 144 Replies 14 Participants Last post by  sakibomb
So its still here, like had guessed. I've had 5 people email me for more pictures, telling me they are alll "very interested" and yet nobody has come to look at it. So this weekend i had enough to afford a 1/2" hammer drill and had a 5/8" drill bit in the garage. I went ahead and drilled the bastard out and the helicoil tries to thread it snuggly. I suppose later this week i'll pick up the 45 dollar kit from napa and seal that bizzle in.

I was using a compression style ignition tester. Mostly cause it was 3.99 at harbor freight and I always heard there were great for older things and small engines. Well lately i've become the neighborhood lawn mower repair guy. I thought pic one up and see how nice it is. Well something interesting happpened. My plugs on the twin are carbon fouled to the extreme. This is with less than 6 miles. I noticed with the compression tester i got one hell of an intermitant spark. I then noticed my batteries voltage was 11.59 at state of charge. I'm almost beginning to wonder if the stator isn't working.

I'll find out once i put the new plug in later this week. I figured i might as well fix it since having it run fine when someone looks at it may sell better than "i swear it only needs this done." I still don't plan on going much farther with it after this but if nobody comes by within the next week i may do some more work on it. I still don't really want to but i have this feeling i may keep it. Anybody have a triple clamp for a broke jobless bastard such as myself?? lol

I don't have much but i'm willing to neogotiate some prices. I may get lucky this week though. I went to a ford dealer this week and actually seemed to be pretty interested in myself. So maybe i'll have a job and :) get the stupid 4 foot tall 6 foot wide tool chest out of my garage and back into a shop. Plus its withing minutes from where i live so i'm really hoping i get this. Plus since i'm also staying with my parents and virtually have no bills i'm ok with very few labor hours a week. It would be more than i'm banking now thats for sure.
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Alright so i did a bit more work on her today and found some stuff i've never noticed/and been able to fix finally.

Finished welding the small spots it was leakin the in mufflers. Also instead of attempting to reweld all the rusty steel in the baffle plate i just took an air hammer and put about 6 holes in each one to "balance" the bad muffler with the half decent one. Seemed to make the engine idle better and now it has more of a harley sound lol. I still need torpedo's but this is a cheap fix.

Next i adjusted the floats higher. I ordered carb kits but those won't be here till like wednesday of this week. This was more or less a test to see if it would work. Bike started easier, not nearly as much cranking and throttle needed. 1 Gear, all the way to 8K not one misfire or buck. 2nd, just as strong. Stop sign.............stall lol.

So satified with the idea i left them be till i get my parts in and i'll reset them and see what happens. Plugs are still black, just not as wet looking.

So while it was idling in my driveway, i would rev it a few times and it would crack on the R cyl. I then noticed a back fire shooting out between the carbs and head.

Ah hah! An air leak, i'm not sure why i did this but i didn't put any RTV of any sort on the gasket surface. So i took off the carb boots, hondabond on both sides of the gasket, rebolted, bike revs down very quick now and crackle is gone. I'm done with it now, but glad to see i could finally make some sort of progress instead of going backwards for once.
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I'm bidding on a cyl head and valve cover for a 360. I have no idea wtf is up with my current head but i'm ditching it. I've had to helicoil a spark plug and its still not perfectly sealed.............which thats mostly my fault. There is still a broken stud inside the head the the exhaust is on pretty tight but not how i'd like it. I got it on ebay but someone clearly buggered with the one i got before i got it.

This one seems to be unmolested. I'm going to inspect the hell out of it before i swap them, hopefully being there's hardly any miles on the head gasket i won't need another. That and i've taken the damn top end off so many times now i'll bet i could swap heads within an hour. :roll:

However i think this is the root of most of my random weird problems. Well that and the retarded air leak i never noticed between the intake boots and cyl head.

Truthfully i'm almost enjoying throwing money at it now. The kawasaki has still taken me 1600 miles since december but i would love to have a more comfy bike to ride. The saki is great but i'm a giant on it and it has clubmans. The honda is stock so i have a more upright sitting posistion.

Back to the head, i still think its leaking somewhere. On the ....L side that isn't messed up oil seems to mysteriously leak out through the middle area above the spark plug hole....almost like there's a crack i can't find.

Anyway i'm rambling on, i'm tired, half drunk, got off work about 4 hours ago. I suppose i shoudl go to bed. Just simply stating to not bid on that since i need it lol. I've got 2 days to go , you best bet i'm gonna be watching that like a hawk.....espically since its only 9.99 w/o shipping an dhandleling.
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I think i may have to get these too! 30 bucks! I don't care about the head pipes since they state one has a hole. I just want the damn mufflers. damnit i wish i had my paycheck now, i can't stand waiting till thursday night, my ebay fingers are wanting to go click paynow!
Geez mate, those mufflers are a bit shaggy...maybe spending a little extra will net you a pair that you would be happier with in the long run? These look pretty rusty where it counts...
Here are the same mufflers, brand new for only $15 more...

>ebay link<
sakibomb said:
........ hopefully being there's hardly any miles on the head gasket i won't need another.
Head gaskets are only designed to be used once. Once they are installed and "crushed" they will probably not seal properly again. Given the problems you've had, I think you'll be chasing your tail if you try to reinstall a used head gasket, regardless of the miles on it.
MNellis said:
sakibomb said:
........ hopefully being there's hardly any miles on the head gasket i won't need another.
Head gaskets are only designed to be used once. Once they are installed and "crushed" they will probably not seal properly again. Given the problems you've had, I think you'll be chasing your tail if you try to reinstall a used head gasket, regardless of the miles on it.
I had a feeling. I know most every gasket is really only meant to be used once. I also didn't think i could use the same gasket as the torque it requires is much more than the others so naturally its going to be crushed more.

O well, if i get the head on ebay i'll just get a gasket when i got the dough and i'll do the swap down the road.

I also.........and i can't believe i'm admitting this, JB welded my spark plug insert. And to my suprise i got 153psi. I'm not sure why i never remembered this but i do recall pouring water into the valves when i first got it and do remember a small trickle coming through the valves.................. i think.

So i think i know why its still only at L160 R152 But anyway to my surpise the JB weld worked pimp. I've never really used it on anything besides an exhaust pipe before. I couldn't believe it when the compression jumped up to 150 in only like 4 cranks. I thought it woudl take much longer. No air leak or anything. Crazy stuff. But i still think that head is junk. The next one i'm going to look over better. Carb kits go on friday, i'll see how good she's runnin then.
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Minnesota Driver said:
Here are the same mufflers, brand new for only $15 more...

>ebay link<
Thanks, if thats still there tonight after i get my check i'm clicking buy it now. 45 bucks with FREE SHIPPING.

Uh...........thats a hell yea. The cb360 head is still going for 9.99. I hope i get lucky on that. Even though the bike pissed me off a few months ago i really am beginning to enjoy wrenching on it again, i would love to show off to the saki what this honda can do.

:edit: Actually those are 1 3/8". I need 1 1/2" pipes. Truthfully i want to get two flanges and just weld the flanges on so i can just bolt pipes on rather than the band. I dont know how much easier than that would be if any but just seems easier.

I got my cb360 carb kits in and they look awesome.

I pick up the carbs and take them over, the CB360's main and pilot are much smaller. I take the carbs inside and begin to swap parts and everything is too small.

So............someone show me cb360 carbs.......i'm beginning to think i don't have the right ones. I know they inlet is 50.5mm and the outlet of the carb is 40mm.

After just putting those number down i think something is horribly wrong now. ... ccessories

My carb kits are K&L and have a few more goodies in them but nearly identical to these. I'm almost for certain the wrong carbs are on my bike...........please tell me these aren't 450's.

:edit: ok i found a stamping on the side. Keihin 745B's. According to a webpage i found these are cb360 carbs. Was there some 360's that didn't have CV's?
I'm not positive but I seem to remember a lot of people having problems with K&L carb kits having the wrong size jets included with them.. I've never ordered a carb kit in my life. Just careful cleaning of the jets and installed new float needle valves, and everything I've ever worked on ran great.

I just installed a new float needle valve/seat, and new gaskets in a Zenith carb on one of my Allis Chalmers C tractors yesterday. It was leaking fuel from the overflow. That carb was screwed by the look of it too. Dirt and grime over an inch thick in places, bowl full of sediment, varnish, etc. The throttle response is amazing now, and no more leaking fuel.. ;) No new jets were installed. Those jets were the originals from the early 1940's.....

GB :mrgreen:
My triple still has the same jets in it when it was purchased. I just cleaned them up, i understand how little things can screw with them but in my mind its pretty hard to screw up a carb just by running the bike all the time.

However in the honda's case i think the fuel seat is bad and leaking gas in. The intake tubes were wet again today and the last time i ran the bike was a few days ago. Fuel's been turned off, boots were cleaned before i put hte carbs on. Nothing was done and more gas is in he tubes. So to work i go today.


I would like to nominate myself for the homer award.

I took the carbs to my guy and he glanced at them and checked things over matching numbers and said yea these are actually the right ones. I mentioned that the main jet don't look anything like the ones on the carbs.

He looks over and says "o those, those just hold the main jets. I'll bet on all of those mikuni's you've worked on there's never been a main jet holding tube."
" wait what?"
"Yea this, you break it loose with a wrench and thread the jet out the top"

at this point i noticed the surface lip he was referring to. I've cleaned the jets multiple times but never noticed a break at the top of the holder. I thought the entire tube thing was the main jet.

So i left with a laugh, and sized myself for a new First Gear armor jacket. Lesson learned, working on the carbs now lol. Still trying a good method to get the fuel seats out. Was going to get a screw extractor and see if that works.
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How have you come to the conclusion that the float needle valve seats are worn? If you use new float needle valves does it still pour fuel from them when the float needle valve is fully seated?

GB :mrgreen:


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........... :evil: :evil: :evil: :evil: :evil: :evil: :evil: :evil: :evil: :evil:

Nothing has really changed except the throttle response. Quick up, fast down. No biggie, have the carb floats at 18.5mm. Bike starts, bucks like crazy in first gear, stop sign it dies.

I fuckin hate this bike. I spend money on it only for it to just laugh in my face. I guess i'll stick it in the corner again still i dont' feel like pushing it over a cliff.

On a side note my fuel seats o-rings were torn as well on both carbs.

And you can still see it backfire occasionally through the R carb.
Alright, so i did a few things a few moments ago to maybe pin point the problem.

The plugs aren't actually as bad as they were. The tips are pretty white and the electrode themselves on the L is a nice medium brown and the R is black.

Could be a spark issue but i'm still not convinced thats it. So while it was idling i throttled it up slowly till it backfired the most. Once it sounded like popcorn it got to certain point where it was almost like a two stroke where all of a sudden it has power.

OK so i go down the road and while its rolling i clutch and Rev it up and dump the clutch just wanting to see what it would do. EXTREME SHUDDERING.

So i park it and begin to try to think of what is going on. My dad wants to see it and as its idling it dies and when it starts i put it in first and i almost dump the bike it shudders so much. Its becoming a death trap and an annoyance. If i dont' win the ebay auction for a new head i'm putting it on craigslist again. If that doesn't work eBay. Either way it needs to leave my garage.

Unless......... someone can come up with an idea of whats wrong. I've tested the coils and they are fine, the spark plug caps were replaced with 0 ohm ones and i forget the reading but its within spec easily. Only thing i can think of would maybe be points or condensors. But as said, when i adjusted the floats to out of spec range it began to run correctly.
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Have you synched the carbs? I recommend getting a pair of screw in ports just like Hogie did and making up a simple vaccuum guage to eliminate one more possibility from your ****-list.
I may try something like that. I just can't figure out this stupid bucking thing.

I keep checking the plugs and they are actually turning a nice brown color like its running correctly. I really wonder if its the coils though. I haven't replaced them but under a load it will act completely different. If you run it in first gear on the stand you can't make it do its stupid buck.

The moment you put it on the ground it struggles. What i just don't get is when its in any other gear it pulls just fine but doesn't do its stupid thing.

Something else that i HAVEN'T replaced that might cause this

I have never replaced the points or the condensors. I checked both spark plugs a bit ago and they are both some what a purpleish color.

I only have one friend that is into cars/motorcycles but i fear if had him look at it he would thrash the hell out of it and try to do wheelies and stoppies or something retarded.

I let him look at my triple before i realized one carb was missing pieces and sure enough, cold start straight to 8K. Naturally this was also at like 1am. It died and i told him i would just figure it out the next day. Naturally since he was half way down the street he was determined to get it back to my apt. So rev'n loud and dying he continued back to my apt. I'm suprised no one called the police.

After that, i never had him look at my **** again. Kinda pissed me off how he treated my baby.

I'm one of those understanding people who closes car doors easily, drives a car but doesn't put it to the extreme, shows appreciation for something that isn't mine.

How the hell am i a technician with no other car f'd up is that??!?!
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Bird76Mojo said:
How have you come to the conclusion that the float needle valve seats are worn? If you use new float needle valves does it still pour fuel from them when the float needle valve is fully seated?

GB :mrgreen:
I have no idea, i know when i pulled out the old fuel seats both rubber seals were torn. When i was talking to Ron at the cycle store he mentioned my capped off pilot jets were for cold starting and some bikes use them and some don't.

I'm almost afraid to ask this but should they in fact be capped off. I'm just so confused cause when i got the bike from my friend he never mentioned it doing anything stupid/weird. Only thing i did that would have changed stuff was i rebuilt the engine and adjusted the carb floats to 18.5mm.

Tis a shame the engine had to self destruct then before i had a chance to ride it. otherwise i might have had a clue what was up. As for the vaccum lines i may hit up a hardware store tomorrow or find someone that would have something i could use. I only have one Vac. gauge but i could still do things one at a time.
The bucking in first - I know this may be obvious but what's your chain slack look like? Clutch cable has a tiny bit of slack?

The pilot jets on those carbs I really have no idea? I'm at a loss man.

GB :mrgreen:
sakibomb said:
As for the vaccum lines i may hit up a hardware store tomorrow or find someone that would have something i could use. I only have one Vac. gauge but i could still do things one at a time.
Dude, did you even look at Hogies pages? Screw the hardware store, just order in the 5mm adapters from Motion muss-no fuss. As for the synch guage you can make one for only a few dollars that will do both carbs together (hence the synching).

I strongly recommend you synch the carbs before pointing the stick at other carby curiosities.
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