Topic: 78 matic will only run with choke.. please help!

[totherunner43]

Hello everybody! So i picked up a 78 hondamatic in really good condition. its been in a garage sense 2003 though. But its running now and i drove it around town and on the highway this past weekend sesne it was nice out (i live in Denver...) and everytime i turn the choke off and put it in gear and go to drive it will die. now i have noticed that idle solenoid is not really doing its job to well as the idel between nuteral and first gear do not change. I think this may be my problem but i am not sure also, not to familar with these bikes all to much and i understand that this hondamatic aint quite the fast bike, but i am really surprised at how ssssssssslllllllllllooooooooooowwwwwwwww it will accelarate. I had to let a grandma in an oldsmobile pass be sense i could not pick up enough to get infront of her!! is this just me or is that the norm for the rest of you guys? thanks for reading and i hope to hear back from someone!

[raymond10078]

If the idle doesn't change when shifting from neutral to first, then the idle solenoid is working.  When the idle solenoid isn't working, the idle will noticeably drop when you shift into gear.  Regardless, you can watch the dashpot/diaphram "pull in" when going from neutral to drive (this test best done with the bike on the centerstand, and the park brake locked).

If you are saying that even when the bike if fully warmed up - and you turn off the choke, the bike dies (or won't idle) - sounds like you need a carb rebuild.  These carbs are very, very finicky - and must be very, very clean.  Is the gas tank rust free?  Regardless a fuel filter is always good insurance and recommended by most.

My 78A is slow from a stop, but when it gets rolling 20 mph or so, it picks up pretty good.  Was this the 78A on craigslist?  I believe I saw one for sale on the south side of the metro (not in Denver but south)?  I was just in Denver this past weekend - could have stopped by . . . .

At least in Denver you do have help nearby, if you can't do things yourself.  Hondaman lives in Englewood (I think), or thereabouts.

[salukispeed]

Sounds like the carbs are in need of a good cleaning and adjusting including sync. It is usually a good idea to review and do a real tune including points adjustment and timing. When I got my 77 the point advancer was siezed and never advanced beyond base timing and the performance of my 1966 305 dream was better. Now with everything fixed it runs fine and performs a lot like an old school 550 or 650 and highway speeds and passing is no real issue. Definately no powerhouse but a nice easy going daily driver.

[totherunner43]

thanks for the response!

kandrtech... tomorrow is my day off and i will take a look at the idle solenoid a little closer. When the bike is fully warmed it will idle in gear and nuteral, just when i put it in gear and touch the trottle it wants to die... and i hope it is not a carb issue because i just got done paying a shop $750 dollars to rebuild them!!!!! There might be a little rust in the gas tank too but i do have a fuel filter. I am starting to think this shop did not do to much for me 

and no this is not the 78A from craigslist. I actually picked it up from a friend i work with at Coors Brewery. He got it from an older gentlemen who had bought it back in 2003 in wyomming then passed away while trying to restore it. From my understanding this bike has not ran sense 2003 and I took it on its first ride over the weekend

I might have to look up this hondaman.... I know of a guy in the northern denver area that has been a savior as far as parts and knowledge of this auto's and 750s...


salukispeed... The guys at the shop said they did the cleaning and sync. I am assuming they adjusted the time and points as well. I will look into it more deeply though, thanks for the advice!

[totherunner43]

well, i checked the selnoid and it is working. i adjusted the idle and that did not fix it. i also sprayed some carb cleaner around everything with the bike running to check to see if there were any vaccum leaks and i am all sealed up.. BUT, and i appologize for my stupidity but i did not mention to you guys earlier about my airbox. the airbox that came with the bike when i got it was missing on of the 2 nuts that holds it together and i was riding around with the airbox not fully closed up. There is also a K&N filter and not the oem filter. i talked to my parts guy about it and also the shop that i sent it to and so i was told that it might not be getting the proper air ristriction... The bike does ride well with the choke slightly on and i am hoping that once i get my hands on a new airbox and orginal air fliter that it will solve my issuse. i do have a question for you all, the airbox reads 750 F on it. are these airboxs the same between the A models and the F models?? anyway, here is a picture of this bad boy for you

[raymond10078]

Sorry to say - but I think you are on the wrong path.

I (and others) run a K&N with no problems.

The air box top on the A for the 78 is unique to that year(#17 on parts fiche) - but I don't see how this could EVER cause the condition you describe.

The air box mid piece on the A is the same as the 77/78 K and F models (#12 on fiche).

The air box bottom on the A is the same as the 76/77/78 F and 77/78 K models (#13 on fiche).

The mid piece and the bottom were changed over the years - more restrictive - so if these two weren't right, you may be on to something - but since the parts are the same as the F bike, your theory goes out the window for these two parts.

I would ask your shop if the pulled and cleaned the emulsion tubes.

Lastly, be careful about a stock air filter. I bought one from ebay - it was not original Honda - it looked stock, but was too restrictive.

[salukispeed]

2nd that on the K&N. Never had any real problem with one. Does the air cleaner top have the rubber stacks in it. Had a guy years ago that cut the stacks off in the box thinking he got more air that way. Didn't run well off idle and mid range. I believe they are matched to the carbs/intake runner length and necessary.

[dave the welder]

3rd on the K&N the one i am using i bought over 30 years ago.just cleaned and re oiled.p.s  i think i got my moneys worth out of it

[Stev-o]

$750 for a carb rebuild? Sorry to say, but you were robbed.
Hondaman charges $200....


http://sohc4shop.com/catalog/index.php?manufacturers_id=12

[totherunner43]

I would ask your shop if the pulled and cleaned the emulsion tubes.

Thanks for the info and heads up! i will look into it and let the shop know!

2nd that on the K&N. Never had any real problem with one. Does the air cleaner top have the rubber stacks in it. Had a guy years ago that cut the stacks off in the box thinking he got more air that way. Didn't run well off idle and mid range. I believe they are matched to the carbs/intake runner length and necessary.

Hmmm not sure, i will look into it though, thanks!

$750 for a carb rebuild? Sorry to say, but you were robbed.
Hondaman charges $200....

yeah i would say so It was not just a carb clean that they did but i still feel a little ripped off seeing how they gave me the bike back not fully working properly but sure as hell charged me as if it was... i am having them fix it and i am not giving them a cent more... thanks for that link!

[chickenman_26]

$750 for a carb rebuild? Sorry to say, but you were robbed.
Hondaman charges $200....

I suspect Hondaman isn't running a 10,000 square foot dealership with 20 employees and all the rest of the overhead. The amount paid is less important than the result. Why would anyone pay $750 or any other amount to NOT fix the problem? Where do I get a gig like that? I wish consumers were a lot more aggressive about not paying these lazy, ignorant clowns until after a short test ride before taking delivery.

I was in a dealership service department last week where one mechanic had been struggling with a set of GL1500 carbs. I asked how it was coming with that, and he says "all finished. They're right in front of you".
All I saw was a set of the filthiest carb rack I've seen in a long time. He'd pulled the float bowls and sprayed out the guts with carb cleaner. The customer got a $700 bill. 

Stu

[totherunner43]

I wish consumers were a lot more aggressive about not paying these lazy, ignorant clowns until after a short test ride before taking delivery.

well when i picked up my back it fired right up.. first click of the starter. then it idled for a while and i went and payed. The guy told me that i would need to leave my choke on until it warmed up a little more then i could put it down. So i drive it the 20 miles to my house and put the choke down and it did not want to stay running. I called them right back and the next buisness day i was dropping it back off at the shop. I do not plan on giving them 1 more cent. They realize this too... hopefully haha

[chickenman_26]

well when i picked up my back it fired right up.. first click of the starter. then it idled for a while...

With the choke partially on, I assume? The choke has an idle-up feature that likely kept it from stalling. By the time you got back from paying, the bike should have been more than warm enough to ride with no choke applied. One has to wonder...if the bike still won't idle without the choke on after 20 miles of highway use, how in hell did the "technician" set both the warm base idle rpm and the in-gear rpm? With the choke partially on?     My money is on plugged idle jets, and I'm certain that guy doesn't even know how to remove them for cleaning.

The guy told me that i would need to leave my choke on until it warmed up a little more then i could put it down. So i drive it the 20 miles to my house and put the choke down and it did not want to stay running.

Never ride with the choke on, especially not for 20 miles. All that's likely to do is foul plugs and compromise cylinder/ring lubrication.

I called them right back and the next buisness day i was dropping it back off at the shop. I do not plan on giving them 1 more cent. They realize this too... hopefully haha

Yes, I'm sure they realize it. I'm definitely on your side here, but the problem now is that they have your payment. What's their incentive to keep at it (for no additional pay) till they get it right? I wish you luck, but I've seen this play too many times before. And it seldom ends well.

Stu O

[motorhead419]

That sounds like a case of plugged up pilot jets to me. Them pin holes must be fully clear and the correct float level for them to work properly.

[totherunner43]

chickenman_26... i hear what your saying. i appricaite what your saying and thats why i started my account and reached out for you guys sense this is my first A and i am still pretty new in the world of motorcycles. I dont wanna be ripped off and i am not gonna let them screw me anymore then they have. I am still a man and no how to deal with these type of people. in all reality all i want to do is ride the bike hahaha.

That sounds like a case of plugged up pilot jets to me. Them pin holes must be fully clear and the correct float level for them to work properly.

i am afriad of that... i stressed it to them when i saw them to, so we will see what has changed when i go back to pick it up.

[78unknownA]

im running into the same problem with only the choke being on, is it possible to pull the carbs off and clean the idle jets and put them back on without resycing them. or should I wait until I buy one, wanting to fix it but dont want to make more problems for myself.....