CL360 High Idle

[Arne]

I'm working on a buddies 1973 Honda CL360 and for some reason it idles really high once its warmed up.

Can't find any airleaks and everything in the carbs are clean. Starts great, runs great, but when it's warm the idle just goes right up.

Carbs are balanced, timing is on, jets are correct, idle screw is right on, all the standard stuff seems correct.

Anybody had one of these before that could point me in the right direction?

Arne

[rngdng]

Maybe a valve problem, or leaky headgasket. I don't know, that thing has too many strokes!


Lane

[Arne]

Maybe a valve problem, or leaky headgasket. I don't know, that thing has too many strokes!


Lane

Good point - I don't necessarily think twice about the valves if they have good compression. I'll run them through the paces.

Thanks - Arne

[frappy]

Arne, Ever figure out this one? Dane

[Arne]

I picked up a running complete parts engine from a 1976 CB360t with the carbs and a set of carb kits for it, so it'll be running soon.

Apparently the mechanical spark advancer likes to stick open on these but that isn't it on this one.

If I had to venture a guess I'd say the valves are leaking air by their seals when its warm (it smokes a bit out of the cam breather tube.)

I can't seem to see any issue with the carbs, but a different set off a similar model (carbs from the CL360 and the CB360t have same jets and general fitup but are a couple numbers off in the parts numbers)

I'm hoping to get to switching the parts over tonight, just haven't gotten to it with my work going crazy (we've been overly busy lately with the past weak dollar, but I'm waiting to see what happens now while it's getting stronger - international work throws a few curveballs in the budgets that way.)

It snowed out now, so I imagine I'll get some more garage time in as well.

I'll let you know how it turns out, this appears to be a fairly common problem with the CL360's and CB360's (but it's fairly common with all carbureted motorcycles in general so that's probably not saying much).

[Arne]

Well, it runs good now.

It has:

New used carbs, cam, cam housing, valves, head off a 76 CB360T.
New carb kits.


Its a bit funny though, I basically put a new top end on the bike and it didn't start at all.

Then I pulled off the in line fuel filters I told my buddy to throw on there and it ran perfectly (they were the good filter fabric glass type in line fuel filters).

I hope the fuel filters weren't the problem all along, but I guess it'll be hard to tell now.

Anyways, if I had to guess I'd say the valve seals were leaking air in and blowing smoke out the breather.

Good luck! Arne

[frappy]

A fellow four-stroker on another forum got seriously all over my case when I posted that I was running an in-line filter on my CB350F. Evidently restricts flow of gravity?

He said if the integrity of the petcock's fine brass filter screen is good then there's no need for an addtional in-line filter! I have good petcock screens now and no longer run in-line filters on my Hondas.

(I do wonder about the petcock "cigarette filter" screen on my T500 as in addition to the one attached to my petcock - 2 loose ones came out when I cleaned my tank. Wonder how long those were in there!)

[rngdng]

A decent in-line filter will not significantly affect your fuel flow. Also, I have had crap from the tank get through the filters in the tank, and the petcock, which the inline filter caught.

You may notice that some "classic" Honda guys are extremely anal-retentive, and a bit delusional. Sorta like "classic" Suzuki guys. Some of us aren't.



Lane

[frappy]

What's your definition of a "decent" in-line filer?