Hello everyone, this is my first post after a long time having a few issues with a bike I purchased a couple of years ago. The problem is I can get the bike running just fine with the choke pulled out, I let it warm up a few minutes, and then when I take it out to ride it stalls on me when I pull up to stop sign or whatever. I have taken it to get the carbs cleaned twice professionally, the most recent time the mechanic said it sounded like something wasnt recharging the battery while riding. So, he checked it out and said that I need a new rotor and stator kit but wasn't completely sure this would solve my problem. The things I have done are change oil, put a brand new battery in, replaced ignition switch, fuse box, had the carbs rebuilt (professionally of course). I have heard from a couple of other avid bikers that it may be the regulator. And of course the mechanic I took it to recently said that the rotor/stator kit can only be purchased through honda and would cost upwards of $600. He also said that I could run it ok without it stalling for about 50 miles before I would have to throw the charger on it the battery again. This bike is in nearly perfect condition with only 4000 miles on it. I would love some opinions on where to start. I am going to try to tackle this myself and save me some money. Any advice would be greatly appreciated! I have attached a picture of my beauty. Just wish I could ride it. This bike did sit for a few years in a garage without being ran according to the previous owner. Thats the reason I have had the carbs gone through (also because the floats were getting stuck and causing fuel to leak out of them). It does have fresh gas in tank and no rust or anything inside tank either.
1980 CM400T stalls
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Welcome aboard. Nice example of this model. We'd appreciate a post over in "Member Intro's" to let everyone else know a bit about you and the bike.
I hate to say it but your mechanic does not know this bike at all. The ignition system is completely separate from the charging system. In fact you can run this bike without a battery once you get her started. The electrical system runs all the lights, horn etc. that's all.
The idle speed for this bike is 1200 rpm so if it's set too low then it will stall. You didn't mention if it restarts easily, I'm guessing it does. Are the carb insulators soft and flexible or are they rock hard? You may have a vacuum leak. Are the mixtures set correctly? Carbs sync'd? Typically on these there is very little choke needed to start them and then you shut it off after a minute or so.
PM sent about a manual
I hate to say it but your mechanic does not know this bike at all. The ignition system is completely separate from the charging system. In fact you can run this bike without a battery once you get her started. The electrical system runs all the lights, horn etc. that's all.
The idle speed for this bike is 1200 rpm so if it's set too low then it will stall. You didn't mention if it restarts easily, I'm guessing it does. Are the carb insulators soft and flexible or are they rock hard? You may have a vacuum leak. Are the mixtures set correctly? Carbs sync'd? Typically on these there is very little choke needed to start them and then you shut it off after a minute or so.
PM sent about a manual
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Welcome to the forum. Great to see another 400 series here.....and you are right....it is a 'beauty'.
I would also check the plugs are the proper number.....non-resistor. Are you running it above 3k rpm's regularly?
I would also check the plugs are the proper number.....non-resistor. Are you running it above 3k rpm's regularly?
The plugs were replaced with new ones I purchased from a honda dealer when I first got the bike. The rubber on the carbs seems to be soft. A little stiff but not rock hard. And as far as running it above 3k, I have been trying too but I can't keep it running because of the stalling issue. When I first got the bike and got the oil change and plugs done it was a little difficult to get started and to keep running. Then i had the carbs gone through that next summer by a retired harley dealership owner and he found a few things in there causing float issues. Just recently had them gone through again because of the stalling issue and I thought that would fix it and it didn't. Is syncing the carbs something i can do myself of do I have to have some kind of instrument. I do have a good friend of mine that is willing to help me out with things I may not know how to do HAHA. Im just tired of having to keep taking it in and not have any results because Im taking it to the wrong people. Hopefully with the mass knowledge of all of you guys, we will be able to figure out. Thanks again for your info!
Syncing the carbs requires a manometer or two vacuum gauges. You'll also need two vacuum fittings, the ports are there but are plugged with screws. It's a bit unhandy to get at the adjustment on these bikes.
It's common for folks to clean these carbs multiple times before they get them right. How does the bike run above idle? It could be as simple as getting the idle speed and mixture adjustments right (along with the carb sync).
I agree with Jim, your mechanic may be a wizard with the bikes he knows but he's missing some information here. Possibly if you and he were to sit down with the factory service manual (do you have one?) you would get better results.
It's common for folks to clean these carbs multiple times before they get them right. How does the bike run above idle? It could be as simple as getting the idle speed and mixture adjustments right (along with the carb sync).
I agree with Jim, your mechanic may be a wizard with the bikes he knows but he's missing some information here. Possibly if you and he were to sit down with the factory service manual (do you have one?) you would get better results.
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OK, lets start by getting the basics handled so we know those are done and correct.
Correct plugs, NGK D8EA gapped at .026"
Valve adjustment, .004" intake ,006" exhaust
Compression test, spec is 185 +/- 14 psi
Cam chain adjustment, done at idle directions in the FSM
Get the carbs sync'd, a bit of a PITA to do but you'll get used to it.
Mixtures properly set after the above is done.
To do that ride it for 2-3 miles to get her hot. Put it up on the center stand and adjust the idle speed to 1200. Now adjust one carb to get the highest idle speed, rest the idle to 1200 and adjust the other carb the same way. Reset the idle again and repeat the adjustments. Ride 2-3 miles and recheck.
Correct plugs, NGK D8EA gapped at .026"
Valve adjustment, .004" intake ,006" exhaust
Compression test, spec is 185 +/- 14 psi
Cam chain adjustment, done at idle directions in the FSM
Get the carbs sync'd, a bit of a PITA to do but you'll get used to it.
Mixtures properly set after the above is done.
To do that ride it for 2-3 miles to get her hot. Put it up on the center stand and adjust the idle speed to 1200. Now adjust one carb to get the highest idle speed, rest the idle to 1200 and adjust the other carb the same way. Reset the idle again and repeat the adjustments. Ride 2-3 miles and recheck.
Thanks everyone. Going to possible have someone help me take a look at it this week. I will do my best to get through the list of items you wrote out Longdistancerider. I will let you know how it turns out. Also going to take a look at possibly buying one of those carb adjusting tools if my friend doesn't already have one.
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Model #08-0119, I just realized I got mine on ebay but the prices are the same ~20.
Awesome thank you thank you!
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This a 6 year old topic, one member hasn't been back since the last post and the other over a year ago. Start a new thread in the SOHC Fuel section with the specifics of year/model modifications and symptoms and we can probably get you straightened out.
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But before you post your question, check your Conversations since this is your first post since joining
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