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'76 cb360 Tappet Confusion

10276 Views 56 Replies 10 Participants Last post by  Brly, 
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I'll do my best to keep this short, but no promises. My brother picked up this 360 a couple years ago. It was not running when he got it and we knew nothing about it. It did come with a Clymer manual. I cleaned the carbs, twice, and did some of the other tune ups out of the Clymer manual, but I was stupid and impatient and skipped some of the more important things. We got the bike running once, but it was only running on the right cylinder, and only with the choke on. We kinda jumped into it without any knowledge of bikes and shortly thereafter, my brother lost interest. Now the bike is basically in my hands. After reading tons about these bikes, I know a tiny bit more about them so I'm pretty much just trying to start over from scratch.

I checked the compression today. Right cylinder was at 150 psi, left was at 145 psi, everything good there. Then I went to valve adjustment and ran into a problem. I followed the Clymer manual which states turning the alternator until the intake valve opens completely and then starts to close, then continue turning until the LT mark lines up with the index mark. "Note that both valves for the left cylinder are fully closed at this point."....... They're not.

When my brother and I worked on this bike, I did pretty much all of the mechanical stuff except for one part that I wasn't around for. The head gasket was leaking, and since he had a gasket for it, he decided to put it on. I honestly don't know what the top end of that motor looks like, but I'm thinking the cam was not oriented correctly when he put it back together. Any thoughts on this? What else could it be?

Also, if this problem gets worked out and I can actually adjust the valves, where exactly do you put the feeler gauge? The Clymer manual says insert a .002 inch feeler gauge between the tappet adjuster screw and valve stem but I just don't get it. Am I having trouble with this because of the above mentioned problem?

If there's any more information needed, let me know, I'll see what I can find. Any help will be greatly appreciated.

Ben
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Wow, thanks for the quick reply. I forgot to mention that I performed the cam chain adjustment per Clymer. This is the same as the timing chain correct? The book says that chain slack will automatically be taken up by the tensioner mechanism, but how do I know that for sure? I vaguely recall reading something to the tone of gunk interfering with the auto chain tensioner. Could this be the case here?

Thanks again,
Ben
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tbpmusic, big time thanks for the manual.

A few questions.
When I did the compression test, the bike was cold because it doesn't run, and it was like 30 degrees. Should I try to warm it up with a torpedo heater or somethin? I understand the difference that will be made with a warm engine. Also, I didn't check to see if the choke was on or off as it wasn't mentioned in the Clymer book. I did have the throttle wide open; at least I got one part of it right.

About the cam/crank timing. Am I missing something in the Honda manual? Everything I found referred to the cam chain tensioner and how to loosen the lock nut and let the tensioner do its work. What I'm asking is how do I adjust the cam/crank timing?

Thanks,
Ben
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I will definitely check the compression again.

I'm still not sure what is happening. The bike ran on one cylinder after the top end had been put back together, and you say that the bike will not run if the cam sprocket is not aligned correctly, so does the fact that it ran rule out that problem?

I have to go over the valve adjustment again because the Honda manual is quite a bit different than the Clymer.

I really appreciate your help with this.
Ben
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I'll check it ASAP, but that might not be until this weekend.

Thanks again,
Ben
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Well, I figured out the valves, there was nothing wrong with them or the cam, I just didn't understand what was happening. Anyway, the tappets were a bit snug so I adjusted them and rechecked with the feeler gauge and everything seems to be good there. I reset the points gaps and set the ignition timing.

Then I did the compression test again. Choke off and throttle open, but it was still cold, about 34 degrees. I got 153 psi on the left and 147 on the right. I realize the right cylinder is under the 149 psi mark quoted by the Honda manual, but the bike was stone cold. Also, I read an interesting article by TwoTired over on the SOHC board about using a compression gauge that is meant for testing automobiles, which mine is. So, I would like your opinions, but I honestly feel alright about those numbers. I will do another compression test when I get it running and warmed up.

On to other things. I started going through the wiring, cleaning connections and reassembling with dielectric grease. The harness actually looks to be in good shape, except for the spark plug wires, one of which I completely broke off this afternoon. I'm sure most of you are aware that the plug wire goes into the sealed ignition coil. Is there an aftermarket coil that I can replace the stock coils with or do I have to find the exact Honda replacement? Other options?

Thanks,
Ben
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Thanks guys, I really appreciate it. That's what I wanted to hear. I'll probably be making an order for those parts soon.

tbpmusic, I understand you're concern with the compression. If this bike turns out to be something worth putting that much more time into, I will definitely do the rings and what-not to keep it around. Right at the moment I would like to get it running well and I'll probably kick myself later for not doing it now, but that's how it goes.

You'll be hearing more from me as I progress through this.
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Wooo freakin hooo!

Yesterday and today I worked on putting the bike back together. I got the new ignition coils, wires and caps from mikesxs Thursday (thanks for that), made a bracket to mount them in the same place and got em wired in. I wrapped up all the other stuff I had torn apart and then took the carbs off for a super cleaning in simple green. Got some in-line fuel filters and some new oil this morning, charged the battery, put it all together and fired it up on the first kick. Couldn't believe it! This really made my day.

When I started it, I had the choke on and it idled pretty decent. Then I took the choke off and the idle jumped up to around 2000. From that point if I revved it up to like 4000 and let the throttle back, it would hang at 4000 and very very slowly come down a little, but not all the way down to 2000. I let it run for a while to warm up and after that, it would still idle around 2000 with the choke off and if I put the choke all the way on it would die, but, with the choke somewhere in the middle, I could make it idle anywhere from 1000 to 2000.

When my brother got the bike, the air boxes were gone, but that wasn't a problem because he wanted to put pods on anyway, so he got some. I'm guessing the pods are my problem. I set the mixture screw 1 1/4 turns out and have the idle screw all the way out. To adjust/correct for the pods, I need to increase the jet size, correct? Do I need to replace the main and the pilot? I'm not exactly sure what to do here but I would like to keep the pods.

Also, my brother bought some real cheap emgo slip on shorty mufflers. They're LOUD and they leak terrible at the header/muffler joint. I know I could fix the leak, but I'll probably get something different. Has anybody used the Mac 2-1 they make for this bike? Or do you have any other suggestions? The original mufflers are toast by the way.

Sorry about the long post, I'm just excited.

Thanks for all your help
Ben
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Thanks for the links tbpmusic.

I wouldn't mind getting some up-swept slip on mufflers, I'll have to poke around some more.

I'm glad to hear I might not have to rejet. I guess I should get the mufflers I want before doing the carb sync? I would just have to do it again anyway.

I'll let you know what happens.

Thanks again,
Ben
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If the butterfly valves are the round, thin plate discs that rotate with the shafts, no I didn't take them off when I cleaned the carbs. If the butterfly valve is the linkage piece between the carbs that ties them together, yes I did take those off. I'm not exactly sure which part you are referring to, so let me know if I'm wrong.

Before I sync the carbs, I would like to get the mufflers that I'm gonna stick with. I'm looking for a 2-2 up-swept slip on muffler, I found some that are made to replace OEM BMW mufflers that would fit the 360 header, but they're pretty long at 31 1/2 inches or so. I put a tape measure on the bike tonight and that leaves the end of the pipe all they way out at the end of the rear tire. I'm not sure how good that would look (the stock 360 mufflers are about 28 inches). I'm looking to stay relatively cheap, and I'm keeping in mind that I'll probably get rearsets eventually. I'll continue to look but if anybody has any suggestions, they're very welcome.

Thanks,
Ben
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Thanks MNellis,

If the high idle problem still persists after some other tweaking, I'll give the butterfly valves a second look. I have no idea when this bike ran last and what has been done to it until I got it, so it might be worth a quick look.

Ben
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Well, I'm waiting on some parts to come in so I figured I should start the cosmetics. I just cut the front fender down, needs some filler and then primer, paint,etc. Anyway, this got me thinking about what the bike needs to pass inspection. Some of the bikes I've seen don't have front or rear fenders, turn signals, mirrors or whatever else. How do they pass inspection? Do they bolt the needed parts on and then take em off afterwords?

I'm curious because I won't have a true fender on the rear, just some type of mud guard so I don't throw road grime all over the carbs and motor.

Ben
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Well, I've been busy the last couple weekends. I got wheel bearings and swingarm bushings and put them in, cleaning and inspecting as I went. Finally got everything back together today. I also ended up getting the Emgo wide mouth slip on mufflers. I decided I better try to sync the carbs. I checked the tappets again, then started the bike on the first kick, as usual. I had planned on taking the spark plug cap off of one cylinder and trying to tweak the carb on the running side. Well I popped the right cylinder plug cap off and the bike died. Tried starting on the left cylinder only, no go.

Sometime last week I started the bike and it was running ok for a while. It finally stalled and I couldn't get it started again, so a few days later I went down and it wouldn't start. Then I recalled tbpmusic suggesting new plugs. When I took the old plugs out, both were wet. I put the new plugs in and it fired right up. Today I noticed that after it ran for a while, the right side header was good and hot but the left side was only warm; I could put my hand directly on the left header.

So, the fact that the left header was warm means that the left side had to fire at some point right? For whatever reason, it didn't occur to me to check the spark on the left side. I am getting fuel to both carbs (checked the float bowl cleanout). I got the new mufflers sealed up, no leaks at the joint.

Any ideas?

Appreciate it,
Ben
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I'll recheck the points. I'm confident they were set as good as can be had with static testing. Both ignition coils are brand new from mikesxs. I will check the ignition wiring on the bike itself also.

I don't think its a carb issue at this point, but I could be wrong. After I cleaned the carbs, I put inline fuel filters on so nothing should be plugged up and also the left cylinder was getting gas, noted by the wet spark plug.

I will definitely check the points again. Any other ideas?

Thanks 66sprint,
Ben
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Will do. Thanks guys.

Ben
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Ah, more problems.

I reset the points gap and timing today, fired it up and the left cylinder still won't run. Checked the spark on both sides and the left is definitely weaker than the right. So I started tracing wires around and ended up at the regulator (the regulator is the little cylinder with two posts, one for the positive battery and plug, the other for the starter cable, right?). Anyway, I ended up taking the screws out and pulling the internal wires apart. Stupid. So I need a new regulator. Is this something I can get at Autozone? I've also read about using a rectifier/regulator combo but I don't have the slightest idea of how they would be wired.

Note: The ignition coils are brand new and I will not be using the electric start.

I'd really appreciate any suggestions or comments.

Thanks again,
Ben
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Haha, well I did F up, so you don't have to be nice about it.

YES I would like you to tell me how to bypass it for the time being.

Can't tell you how much you guys have helped me out. Thank you.

Ben
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Sounds easy enough Steve, before I do that there's some more info I found today.

It appears that there isn't even a voltage regulator on the bike at all. I looked the part up on bikebandit.com and also confirmed with the wiring diagram from the Honda manual, and it's not on the bike. From the wiring diagram I see that three wires go to the regulator; black, yellow and green. I found a yellow and green wire, neither of which were plugged into anything. I did not find a spare black wire. Another problem I'm having is that one of the previous owners spliced a lot of wires together. In most cases, a small section of the insulation was cut off, the other wire ends wrapped around that spot and then a drop of solder on everything to hold it tight, finished with a wrap of electrical tape. Everywhere this is done, all of the spliced wires are the same color. Sometimes its three wires but I've seen as many as five spliced this way. To me, not knowing much at all about electrical work, it makes it hard to understand what's going on.

How could I run the bike without frying electrical components without the regulator. I have been blowing one of the 7 amp fuses. One of the wires from that 7 amp fuse goes to the hi/lo beam switch on the left handle bar, the other goes to the right handle bar control, which is brand new.

Let me know what you guys think.

Thanks again Steve.

Ben
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Sounds good Steve. I preferably would not like to use your time telling me how to rewire everything point to point, but that's down the road anyway.

So I'll wire the ignition circuit like you say. I found that the left side spark was weak. What should I be looking for to fix that problem?

Thanks

Ben
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Starting to sound like a broken record here.

The bike starts right up first kick, but only on the right cylinder. When I throttle up to about 3000 RPM and the ignition advances, the left cylinder fires.

I took the points plate off and cleaned the advancer today, then reset the points gap and timing. I tried setting the gap at the low end of the range (.012 I believe) and the upper (.016), timing after each adjustment. No change in the left cylinder. The timing checked out perfect, the test light came on exactly when the proper marks aligned.

I have the ignition wiring jumped over the solenoid like 66sprint advised me to do, from the battery positive directly to the coil wires.

Could this be a carb problem? I'll take em off and clean em again if I have to, but I really thought I got them spotless this last cleaning, and I've had fuel filters on since then.

Excuse my ignorance.

Thanks,
Ben
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