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Discussion Starter #1
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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Yes, it does sound like cam/crank timing is off..... Start there with the timing chain.......
 

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Discussion Starter #3
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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The tensioner takes up the slack, it does NOT adjust the timing to any great extent...The cam and crank MUST be timed together so the valves open and close at the appropriate times Also, remember that left and right are as if you are sitting on the bike......and the crankshaft rotates twice for each cam revolution.....
 

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First off, do yourself a favor and put the Clymer in the outhouse where it belongs.
Here's the Honda Manual -

Much better descriptions of the tuneup procedures here...

Secondly, on page 30 of this manual, it states that 171 psi is the desired compression, and 149 pounds is the "red flag" that indicates a top end job.
So measure your compression again - engine warm, throttle wide open, NO CHOKE.
If you still see the same readings you got before, you have overriding problems to deal with, because the readings you posted would be considered marginal.
Could be caused by tight valve tappets, but more likely bad rings/valves.
 

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Discussion Starter #6
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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Check the compression again, as I outlined. A warm engine will give you maybe +5 pounds or so.

The cam/crank timing cannot be "adjusted" at all. It can only be checked.
With the alternator rotor "LT" mark lined up, the two lines on the cam sprocket should be perfectly horizontal - if they are not, the bike ain't gonna run.

When you put it back together, be sure to observe the Manual's comments about filling the cylinder head's oil bath reservoirs, it's important.....
 

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Discussion Starter #8
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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It may barely run if it's a little off up there, but usually not.
It would affect the compression readings.
Check it and report back.....
 

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Discussion Starter #11
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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There's a post on here about switching to aftermarket coils gotten from MikesXS. TPBMusic did it and thought it worked out quite well. A search will turn up more.

GB :mrgreen:
 

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Ben -

Lots of folks proceed with compression like that, and the bike runs fairly well for a while.
The time is not far away though when it will get hard to start and run crappy.

Yeah, that discussion about compression readings over at SOHC is a good one.
I re-posted it at the now-dead 450 DOHC forum and instantly got flamed severely for my trouble. :? :x :| :cry: So I never posted it here... enough flamage for me.
There's certainly merit to the argument, you can't simply ignore the logic of it.
It's not really an issue with me personally, because my compression gauge is a real old one, one of the very short-stemmed ones with a rubber tip that you jam into the spark plug hole. You wouldn't be able to use it on the Fours because of access, but works fine on the Twins.
Using it, I read over 180 psi on my recently re-built 450 project (valve job, new pistons/rings /bore job).
But compression is one of my pet peeves, so i always harp on it.... you can feel free to join the legions of folks (including Wifey) who ignore most of what I say....

Anyway, Mike's XS shop offers a pretty good deal on replacement coils - I think there's a post with photos I made a while ago in the 450 section here. Almost a bolt-up, just had to make a couple of little mount plates for the 450 - should be about the same on a 360.
I can recommend them highly, they work great, and you can get rid of those nasty old coils for not much money - get some new wires and caps too.
 

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Discussion Starter #15
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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Discussion Starter #16
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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Sounds like your carbs are not synched and balanced - that can cause the idle to hang up.
So can tight intake valves.

You may or may not have to re-jet, don't just assume you need to.
Get those carbs synched up first.
You've been messing with the choke, so you need to put in clean plugs and get some plug readings.
Then think about jets, if required.

There are lots of inexpensive aftermarket mufflers - for about $50 each you can score some real nice, shiny mufflers that work good.
http://www.crc2onlinecatalog.com/Index_Main_Frame.htm

Many times aftermarket mufflers will leak at the exhaust pipe/muffler joint.
Gotta stop that - way down at the bottom in this link you'll see how I did it....
http://home.comcast.net/~tbpmusic/id54.htm
 

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Discussion Starter #18
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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Brly said:
Wooo freakin hooo!
..... 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 you took the carbs apart for cleaning did you remove the throttle butterfly valve from the shaft it's mounted to? How about the choke butterfly valve? Did you remove that from the shaft as well?
 

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Discussion Starter #20
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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