Topic: 75 honda cb360

[Spillman]

ok got bike back today. As im driving down the road it starts sputtering and back firing. then it drops in speed from 55 down to 50 until it stalled.Banged on the carbs a little as i just cleaned and rebuilt them. Didn't wanna kill the battery so I used the kick start and got it running again. But then it wanted to stall if i tried to let it idle. Was able to ride it back home and take the carbs off. Carbs looked good. Gas tank does need a good cleaning. Some rust and gunk. Woundering if something just passed through to the carbs.Any idea why it would stutter like this?

[Spillman]

ok been messing with the throttle screw. its very touchy and somehow it wasn't up high enough so atleast it will idle and not stall. Gonna go take it for a drive now

[martino1972]

did you also clean the filter in the fuel tank..??

[Spillman]

I did. I also cleaned and rebuilt the petcock, the carbs and all new gas lines, filters and such. Just been trying to get bike to actually start. Prolly should have cleaned the tank before I got it running but I got ahead of myself. When it started to lose power i thought it may have been a float stuck. Did start right back up after some taps and along with throttle cable to loose.  Deffenitly gonna have to clean the tank up tho.

[Alan F.]

Does that tank have a vented cap like the sohc4's?  maybe it's clogged with rust and corrosion and needs to be brushed out and oiled?

[cb650]

Clean the tank!!!!  Why would you clean the carbs and petcock just to maybe dump #$%* back into them?

[Bill Vaughan]

Sounds like a fuel starvation problem and as others have advised, clean the tank.  It's certainly the best place to start in terms of identifying the issue.

[schwebel]

Been there done that. I tried to get out of Kreme job once on an old twin. I didn't think the tank looked that bad, but it did the exact same thing. You need to get the rust and gunk out of the tank, and line it. Then reclean you carbs, and check your lines/filter.

[Spillman]

Thanks for the input guys. Little update. I cleaned the tank. used diesel fuel and slingshot bb's. Cleaned it best I could then drained the diesel. Then I took the power washer to the inside and really blasted those bbs around. drained the tank and the bb's. counted and made sure I had all bb's out and flushed the tank two times. I then spayed carb cleaner all over the inside to help ivaporate any water that was left. Once the tank was dry I flushed it twice with gas. Drained it yet agian then put midgrade in. Did some light riding Sunday and about after 10 miles it loss alot of power limped home. Today after work it would start but was very sputtery and did not want to rev up or stay running.  My points are in bad shape, have new ones on the way. One is actually ok but other is very burned and wore. Gonna replace both anyhow.Took the plugs out one still looks new but the other had alot of soot on it. I then checked compression and both are very strong blowing my finger out of the hole. Still waiting on compression gauge to get here to get an accurate reading. before I cleaned the tank i did have some minor back firing out of the left side. It was off and on. I tried bench synching the carbs best I could but could only get bike to 1800 rpms to idle good. Right now I tore the carbs off and am giving them a simple green bath and then will change all the gas lines and filters again. Could the bad points be the culprit or did I miss some junk that slipped into the carbs? Carbs looked really good tho but didnt think to check the fuel flow from the filters.

[Spillman]

also on another note the starter works good when the bike has been running same with the blinkers. If the bike is cold blinkers just light up but wont blink and starter just kinda does nothing. Getting between 13-16 amps when I try to start. Brand new battery, checked the levels in the battery and everything checks out. Found a good buy on ebay for a used starter that I couldnt pass.

[Bill Vaughan]

A few thoughts:

1.  Bad points will greatly affect performance as will inaccurate gaps and timing.  When you get the new point set, be sure to take the time to correctly set gaps and timing, preferably with a timing light.

2.  Starters generally fail when warm/hot - not cold.  I would suspect a voltage problem as opposed to a defective starter.

3.  There can be several issues surrounding non-working winkers.  Again, since they work when warm, it seems like a voltage issue.

You don't want to be replacing parts without good reason, but you should be aware that resistor-type sparkplug boots fail with age.  The problem will manifest itself in intermittent firing.  If your bike has the original boots and one cylinder drops in and out, suspect the boots.  They are still available through Honda.  Of course, this should only be considered after you have changed the points.

[Spillman]

Thanks for the reply. Still waiting on points so no update. Been checking prices online for regulators, nothing but used on ebay that look terrible. Hate to spend what bikebandit is asking so guess I'll decide after points are installed. Woundering if I should upgrade the condensor aswell but will wait to see how it runs with new points. Carbs enjoyed there bath in simple green. the plug boots are newish, bike sat for last 8 years but condensor and most other parts like the boots were replaced before it sat.

[Spillman]

ok a little update. Got my new points and condenser on the bike. gaped the points to service manual specs with a feeler gauge. Borrowed a friends timing light but not sure how to read it. It kept lighting up I would say the same time or very close to when the LF was going pass the stator mark. Is this the way it should be? Also tried adjusting the tappets but if I loosen the adjusting screw I can't get it gaped right and have the nut tight. I just set it back to where it was. Kreemed the tank and recleaned carbs and put new fuel lines on and inline filters on. Bike started right up after letting the bowls fill with gas. Set idle down to 1200 rpms and it idles nice and smooth and the back fire is gone from the left side. I took it 2 miles down to the gas station to fill it up and a test drive, but once I stoppd and turned the bike off I opened the gas tank up and got that whoosh sound. I plugged the vent hole when I kreemed the tank and think some still may have gotten in. Problem is the bike started losing power like it was starved of fuel on the wayhome so I opened the tank up while I was driving and it stalled. Pulled it over and it started right back up and drove it home and it stalled just as I pulled into my driveway. Guess I'll put some acetone in the vent hole and hope that fixes the problem. Anything else I should check on other then vent hole? Bike ran great with alot more power then before on the way to the gas station but the last mile home was a little depressing as I was hoping I was gonna be done tinkering around with the bike.