Author Topic: cb400 poor acceleration  (Read 13847 times)

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Offline txterror

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Re: cb400 poor acceleration
« Reply #75 on: February 08, 2013, 02:29:12 PM »
To the II marks? if so, yes i did.
1975 cb400f

Offline dave500

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Re: cb400 poor acceleration
« Reply #76 on: February 08, 2013, 04:24:56 PM »
at last,im outta here.

Offline txterror

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Re: cb400 poor acceleration
« Reply #77 on: February 09, 2013, 03:24:13 PM »
Thanks for your help dave and all others
1975 cb400f

Offline HondaMan

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Re: cb400 poor acceleration
« Reply #78 on: February 09, 2013, 10:30:15 PM »
I just solved this same problem on a '75 400F.

The emulsifier tube's holes were calcified shut, for the most part. Pulled them all out, ran tiny drills thru them to clean them out, presto...  ;)
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

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Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
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Offline dave500

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Re: cb400 poor acceleration
« Reply #79 on: February 09, 2013, 10:36:03 PM »
the first post he says the carbs are cleaned,do we have to ask every time if the emulsion tubes were part of that cleaning?

Offline txterror

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Re: cb400 poor acceleration
« Reply #80 on: February 11, 2013, 06:58:55 AM »
tubes were cleaned, no updates yet as i am waiting for a brake hose. I dont have the balls to take this sucker out with only back brakes.
1975 cb400f

Offline Ridgerunner

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Re: cb400 poor acceleration
« Reply #81 on: February 11, 2013, 12:18:25 PM »
tubes were cleaned, no updates yet as i am waiting for a brake hose. I dont have the balls to take this sucker out with only back brakes.
Reminds me of one of my brothers golden rules.  "If you can't stop it, don't start it."  And that applies to more than just things with motors.  Like chemical reactions and fights and.....................

Keep us posted on this.
"Good sense is the enemy of creativity" Pablo Piacaso

Offline txterror

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Re: cb400 poor acceleration
« Reply #82 on: February 11, 2013, 02:23:58 PM »
will do
1975 cb400f

Offline txterror

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Re: cb400 poor acceleration
« Reply #83 on: February 12, 2013, 07:19:15 PM »
does anyone have or know where to get 5.5mm fuel hose. Besides the bulk stuff on ebay. Theres a couple listings for smaller lengths but shipping is **it
1975 cb400f

Offline Retro Rocket

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Re: cb400 poor acceleration
« Reply #84 on: February 12, 2013, 08:47:38 PM »
does anyone have or know where to get 5.5mm fuel hose. Besides the bulk stuff on ebay. Theres a couple listings for smaller lengths but shipping is **it

Search the forum mate, there was a member here selling some recently.... ;)
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Offline txterror

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Re: cb400 poor acceleration
« Reply #85 on: February 12, 2013, 08:52:10 PM »
They sold out
1975 cb400f

Offline zachz

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Re: cb400 poor acceleration
« Reply #86 on: February 12, 2013, 09:36:34 PM »
If you've got a VW dealership somewhere in the vicinity, they should have nice metric fuel-grade flex hose available. 

Ah, you're near Houston.  Go have a flying saucer pie for me while you're out.

Offline txterror

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Re: cb400 poor acceleration
« Reply #87 on: February 14, 2013, 03:01:24 PM »
Local Honda Dealership had hose, i got 5' for $13. Flying saucer downtown?
1975 cb400f

Offline HondaMan

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Re: cb400 poor acceleration
« Reply #88 on: February 16, 2013, 09:56:57 PM »
tubes were cleaned, no updates yet as i am waiting for a brake hose. I dont have the balls to take this sucker out with only back brakes.
Reminds me of one of my brothers golden rules.  "If you can't stop it, don't start it."  And that applies to more than just things with motors.  Like chemical reactions and fights and.....................

Keep us posted on this.

I'll bet he never rode a CL72? ;)
They may have had the least front brake of any 250cc bike ever, at least before 1966 when they made it the double-leading-shoe version from the SuperHawks.

I have a fully restored and [now 266cc] CL72 for sale, with the OEM front brake still intact. If you regularly use those spring-type grip builders, you can stop it: if you're a keyboard typer like me, it takes all I've got to generate a good stop up front! Good thing it's only a 250!

I never expected that after my old SuperHawk: that baby could lock the 3.00 front tire solidly!
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline txterror

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Re: cb400 poor acceleration
« Reply #89 on: February 28, 2013, 09:35:21 PM »
Its been a while, as i have not had time to work on the bike. Bikes still accelerating poorly and running rich.But a situation has arose and i need yalls opinions. Im really close to getting this bike right, but man it takes a toll on you (especially your pocket). When its one thing after another. I just wana ride, and not wrench as much. But than again i like having this beaut that you dont see everywhere you look on the road. My options are sell it and get a more modern bike, or keep her and slowly get this bike right. She starts right up but just doesnt pull like she she should. I have spent some long hours cussing and learning, but man. Is a used more modern bike gona be less wrenching and more riding. Or do i have alot of potential with this sucker? I dont know, I thought for sure i could just let her go but i started thinking twice while i was having a little photo shoot with her. Help me decide guys. I feel like its goin to be a never ending battle with this 38 yr old girl money wise. But anyways, I currently have a person lined up for the weekend thats offering $2300, should i take it or keep her? At that price im breaking almost even on what i got into it.
« Last Edit: February 28, 2013, 09:42:36 PM by txterror »
1975 cb400f

Offline hondamatteo

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Re: cb400 poor acceleration
« Reply #90 on: February 28, 2013, 09:45:36 PM »
i know this means pulling the carbs one more time but are you sure your slides are installed the right way? Because they can be installed backwards and if they are they WILL make your bike run rich. I know this from personal experience on my 350f. There is a bevel on one side and it has to face away from the engine.
'74 CB350F

Offline dave500

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Re: cb400 poor acceleration
« Reply #91 on: February 28, 2013, 09:57:17 PM »
if your even half thinking of selling it then your hearts not in this bike,just go ahead and sell it,you said your breaking even,,you want to ride not wrench,,after all the wrenching then you can ride,,but you want to ride now.

Offline Retro Rocket

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Re: cb400 poor acceleration
« Reply #92 on: February 28, 2013, 10:10:04 PM »
Yes, i've noticed a lack of patience from some members on the forum lately....   Hang in there mate, these bikes are ultra reliable once sorted out properly. Why don't you look for another member who's close to help you out..?
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Offline txterror

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Re: cb400 poor acceleration
« Reply #93 on: February 28, 2013, 10:38:00 PM »
Bike started first try today and really got me second guessing my decession to take the $2300. I paid 1500 for it and put another 800 so far and probably gona need to spend more. Is a used modern bike gona be less money hungry? I really wana keep this awsome machine. I just dont want to keep forking money into it. Wish i could just take it to a shop and be done but i know they will take all the money i dont hav. I really dont want to regret selling her in the long run. I took her out for a spin yesterday and noticed the clutch grind/knock a couple short times. Nothing crazy just for a short time while i was trying to shift into first or second i think. Its just lil stuff like this that makes my decision hard. I recently changed clutch plates so wat the heck. Like i said always something. Just really dont know what to do. As these bikes are new to me and dont know how much money its gona take  in the long run to get her right. I do wana ride now but dont wana lose a classic either. Ive read about these old timers that regret selling their cb400's and how much fun they were. Really hipes me up to know that i have a piece of history in my garage. And also that you cant  just go out and buy a 1975 cb400f. Deep breathe
1975 cb400f

Offline dave500

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Re: cb400 poor acceleration
« Reply #94 on: February 28, 2013, 10:58:04 PM »
the modern cb 400 is a great bike if you get them where you are,shops can be good and bad at doing old bikes,you can spend money for a so so result,doing it yourself you can go the extra mile for free,,if your prepared to go the extra mile a few times maybe backtracking along the way,someone who knows these bikes will fix it in a jiffy ill bet?or are you just expecting more power from it than it has?this has four pages now,enough for a complete project thread?

Offline txterror

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Re: cb400 poor acceleration
« Reply #95 on: March 01, 2013, 06:24:57 AM »
Just want a daily commuter for work.
1975 cb400f

Offline flybox1

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Re: cb400 poor acceleration
« Reply #96 on: March 01, 2013, 07:26:10 AM »
lemme ask you this....what is your method for accelerating when you feel it stumble?
do you hammer it like its got FI expecting it to take off?
if you roll it on steady, does it comply?
boggles my mind that this is still occurring with timing/advance set, a good air filter, and carbs clean as you say they are (..which BTW, I still say prove it.  with pictures  ;)  )
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Re: cb400 poor acceleration
« Reply #97 on: March 01, 2013, 09:20:30 AM »
We own these old bikes for different reasons. For me, it's mostly about recreating some of the experiences of my ill-spent youth. I've spent much more money restoring my 400 than I ever expected, but I enjoy wrenching on it and solving its problems. And because it's not my only ride, I can take as long as I need to get it just right.

It seems that none of the above applies to you. This isn't meant as criticism. We have different expectations. My advice would be to sell it and buy something like my SV650. Frankly, the development that occurred over the 30 years between the 1975 Honda 400 and the 2004 Suzuki 650 is pretty amazing. I think you will be happier with something from the 21st century.

Bob

Offline txterror

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Re: cb400 poor acceleration
« Reply #98 on: March 01, 2013, 09:27:51 PM »
Thanks for the posts guys, i really appreciate you opinions. As you guys know far more than i about these machines. Flybox when accellerating the bike would go flat once in higher speeds. Today i went for a good cruz and took it easy on the throttle and it seemed to perform pretty good (complied). I think she has more in her, but i had fun today. Cool Bob and Dave thanks for the suggestions. I will take a look at those slides once i get the carbs off and will also take pics for flybox  ;). Also kinda happy to say that buyer backed out of deal. So i will continue to pick your brains and create project sized threads over my progress (if you wana call it that) of learning this addicting machine. I apologize and really do appreciate you guys taking the time to answer my silly yet helpful questions.

1975 cb400f

Offline dave500

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Re: cb400 poor acceleration
« Reply #99 on: March 01, 2013, 11:28:54 PM »
be patient if you keep it and sort it,all these old bikes are as reliable if not more so once sorted,a simple fuse can stop a bike,dosent make it unreliable though, once you sort why it blew the fuse,and youll know what to look for next time,if the carbs have been hermetically cleaned and your 100% sure dont pull them again,,this is where people get pissed off and sell bikes,repeating the same #$%* to get no gain.