Honda-SOHC

SOHC.co.uk Forums => CB350/400 => Topic started by: yorky10 on April 29, 2013, 09:47:57 PM

Title: fuel starvation?
Post by: yorky10 on April 29, 2013, 09:47:57 PM
hi ,yorky again[R regd400-4],all new carb needles, jets,floats reset,21cm as per the book took apart again,air line in every orifice,timing checked new plugs,now it fires touch of button revs up for a few seconds,dies out.its on its last chance,any ideas.very tired,large scotch later things don't look any better.yorky
Title: Re: fuel starvation?
Post by: Norniron on April 29, 2013, 10:24:46 PM
Is your tank vent clear?
Title: Re: fuel starvation?
Post by: yorky10 on April 30, 2013, 09:27:25 AM
Yes,i have not fitted it yet,?yorky
Title: Re: fuel starvation?
Post by: hairygit on April 30, 2013, 09:32:50 AM
How about the internal filter on the tap, is fuel flowing fast enough from the tap? Unfortunately cleaning the filter on the tap involves removing it from the tank >:(
Title: Re: fuel starvation?
Post by: PatM on June 02, 2013, 11:33:47 AM
Yorky- Did you solve it? Im going back through old posts as I have a similar issue. The bike starts on the button, but has no power after 3k, coughs and splutters as you give it some gas. So, I REPLACED the carbs with some I had rebuilt, new everything. Still the same. I had the fuel tap off a while back and cleaned the filter- Ive even put an inline one it, as I suspected fuel problems. There seems to be a healthy steady fuel fill from the tank, so Im sure its no longer petrol starvation. I cant imagine its points, as I checked them and the timing a while back and it was running fine. I just hope its not something more serious, like a burnt-out valve.
Title: Re: fuel starvation?
Post by: PatM on June 02, 2013, 03:47:38 PM
Oh, don't you just love it when you end up answering your own post and somewhat tail-between -legs for a self-inflicted wound. Anyway, owning up to a problem and hoping I will learn and others might- The problem was that I had put a replacement aftermarket seat on the bike and not ridden it- the seat was blocking off the air-intake. I wouldn't mind, but Id actually had this happen once before, so didn't learn. I took the plugs out and they were sooted up- that was the clue- no air. Anyway- its running now, plenty of poke and revs up nicely. Its a bit hesitant till over 3k, but I think its always been a bit that way- its nearly 2 years since I rode it. Ive ordered a set of replica pipes from DS and some points- to give the old girl a new lease of life. The Hondas just one of those bikes I haven't ridden- you cant ride them all, can you? ;)
Title: Re: fuel starvation?
Post by: K2-K6 on June 03, 2013, 08:22:23 PM
That is amusing PatM, I remember friends doing something similar years ago by putting things like waterproof over-trousers under the seat and getting the same result.

At least you've got it sorted and can take it out in the good weather.
Title: Re: fuel starvation?
Post by: PatM on June 03, 2013, 08:35:08 PM
Note to self and anyone else fitting a fibreglass framed seat- THERE ARE NO BUNGS HOLDING THEM CLEAR OF THE FRAME- you have to fit your old ones.....otherwise the seat and fat arse cover up the carb intake...
Title: Re: fuel starvation?
Post by: yorky10 on June 10, 2013, 08:12:36 AM
bike polisher,tried every thing still no good,not put air filter back on yet so its not your problem..need another set of carbs to check if its my carbs at fault.?yorky .any chance any one got a spare set buy or borrow,
Title: Re: fuel starvation?
Post by: PatM on June 10, 2013, 09:28:56 AM
Yorky- Some nearer will help with a loan set of carbs- Im too far away to be of any help. It does sound like fuel starvation- ie, floats not moving or float bowls not filling. My petcock filter was vey bad when I first got the bike- Im amazed I even got it started,
Title: Re: fuel starvation?
Post by: Rozabikes Tim on June 10, 2013, 01:40:26 PM
Hi Yorky,

I did offer my carbs to try before. They are on the bike but no airbox etc so simple enough to get off. Just across the village from you. If you wish I will gladly pop round with them and add my 5 peneth!

Tim
Title: Re: fuel starvation?
Post by: yorky10 on June 10, 2013, 07:23:38 PM
tim,any help would be very welcome,at the moment I am not doing much after an operation,if offer still stands in a while the imput of a fresh brain may just solve matters,in the mean time I will keep looking for a set of carbs.your welcome to come and look.yorky
Title: Re: fuel starvation?
Post by: Rozabikes Tim on June 11, 2013, 08:49:40 AM
Hope the op not too major. Let me know when you are up to it and I will pop round. PM me with address / phone number. Got a lot on myself for the next week or two.

Tim
Title: Re: fuel starvation?
Post by: yorky10 on June 11, 2013, 07:25:56 PM
will be in touch in a while,thanks again ,yorky
Title: Re: fuel starvation?
Post by: yorky10 on June 26, 2013, 08:33:19 AM
Tim after total rebuild of carbs every spring. washer .jet .fuel runs ok.rubber seal. all been looked at cleaned,the bike now starts on tick over no choke,runs ok ,but still wont rev without choke,float heights spot on timing spot on.?yorky
Title: Re: fuel starvation?
Post by: PatM on June 26, 2013, 01:31:16 PM
Yorky- to me it sounds like too much air is getting in. Are the screws in ok on the inlet stubs where you screw the balancing pipes on? My issues have always been not enough air and thats been restriction on the air-inlet under the seat- I didnt have seat-bungs fitted. Also, if the o rings are worn, then the fuel gets sucked up the sides on the main jet.
Title: Re: fuel starvation?
Post by: fisjon on August 15, 2013, 05:23:21 PM
Hi guys,
If you want to send me your carbs I will ultrasonically clean them and zinc plate all the levers and fixings for £40.
This will include a complete strip and each carbs will receive individual attention. (Putting the carbs in an ultrasonic cleaner as a unit of four will knacker the fuel seals. They will dry out and may disintegrate after some use.)
I will replace nuts, washers and any fuel seals that have passed their sell by date.
You will be responsible for postage and for the cost of any parts required to rebuild.
I will keep you up to date via email as and when including photos of work progress.
Send me a pm for more information.
cheers
john
SimplePortal 2.3.5 © 2008-2012, SimplePortal