running issue. its got me beaten

[aussiegold]

no noise from the primary chain. it is new, along with the primary chain tensioner from a 1200. i did try all the advance curve on the C5. no change. i am reasoning that if the valves seat correctly and no fuel leaks through in a static test, then all would be good in a running situation. in other words, i reckon the spring tension would be good.
i am a little concerned about the effect of high voltage , or rather , high amperage, on an electronic ignition, but i am thinking that it would have some kind of built in protection.
anyway, having got the heads off, i have at least eliminated the valves themselves from the equation.

ps
i would rather be an compulsive obsessive, than an obsessive compulsive......... arty: arty: arty:
it's all good, i will solve this ..

 

[Ansimp]

:doh:

 

[aussiegold]

not a lot of work done on this problem so far, been a bit busy with other things :moped:
what i have done so far is too much to list here. i have decided to work with just this carb rack. ( almost new ) and i am also certain the C5 is working correctly.
i have just given the valves a little going over and i am satisfied all is good there. the engine has been bored, honed, new Honda pistons and rings.
these carbs have all new ( Randakk ) o rings and new Honda float valves and seats. little or no firing on cylinder one . first i have switched the plugs and wires , still no go. now, this is at idle ,
when i lift the revs, it may or may not be firing. i am in the process of making a fitting to fit into the fuel bowl drain screw to see the level of fuel in each bowl while running.
as my boss says... one :sensored: up at a time... :smilie_happy:
it idles very well on three pots, i am putting this down to the high performance of the C5. i am posting a link to a video of it running and pullimg the plug leads ,one at a time ( hope it works ) :clapping:
https://vid1335.photobucket.com/albums/w ... 72ef0a.mp4

 

[joedrum]

ok we are at number 1 ....you should run it like that a bit like the video ...them pull that plug and see if it getting drowned in gas or dry ....if heads good.... compression good ...spark good ...it has to be in the intake runner or carb....or the gas feed to this carb ....

seems your getting close ...from look of plugs fronm the pics id say it straving for gas ...witch makes me think its leaking air here ...but id for sure try to figure for sure whats up drowned or straced before taking anything off ...i might take that intake horn off and re seal it in hopes its leaking a bit of air ...it tough with the stock carbs all tied together you cant work one by itself ..... opcorn:

 

[Ansimp]

Getting closer :good:

 

[mcgovern61]

Switched the plugs and wires and no difference when you pull #1 wire still?

 

[aussiegold]

mcgovern61 » Mon Oct 06, 2014 6:20 am[/url]":2obynkrc]
Switched the plugs and wires and no difference when you pull #1 wire still?

no, no difference. and (as Joe suggested ) i had let it run for a while and pulled the plug. dry as the proverbial......
so, for what ever reason, no ( or not much ) fuel getting to that cylinder at idle. i am making a fitting for the fuel bowls out of an old fuel
bowl drain plug, an air fitting and some clear hose . so i can see the actual float levels when running. if they are ok then, move on to the internals ( again ) :wave:

 

[dan filipi]

aussiegold » Sun Oct 05, 2014 5:36 pm[/url]":18w45lui]

mcgovern61 » Mon Oct 06, 2014 6:20 am[/url]":18w45lui]
Switched the plugs and wires and no difference when you pull #1 wire still?

no, no difference. and (as Joe suggested ) i had let it run for a while and pulled the plug. dry as the proverbial......
so, for what ever reason, no ( or not much ) fuel getting to that cylinder at idle. i am making a fitting for the fuel bowls out of an old fuel
bowl drain plug, an air fitting and some clear hose . so i can see the actual float levels when running. if they are ok then, move on to the internals ( again ) :wave:

Ok but as I understand it your having the same problem running a different rack, a rack that runs fine on another engine?

 

[aussiegold]

yes. :head bang: and its a little too much too think that the other rack would have the symptoms on this bike and not the LTD.
but having had the heads off, all valves removed and cleaned again, and it most definitely has spark, the only thing it can be is fuel.
my compression tool is a cheapy and i cant rely on its accuracy , but all cylinders are even .
so, with all that looked at , i have decided to get it running right with this rack.
it's keeping me awake at night........ :smilie_happy:

 

[Steve83]

Did you check the fuel pump pressure? You said it has good flow, but low fuel pressure would cause a lean condition. It just doesn't make sense for a carb rack to work perfect on one bike, and act up on another, unless there's a fuel delivery issue.
Another thought - could it be something causing rolling resistance? Wheel bearings, dragging brakes, too much oil in the engine... :headscratch:

Has anything in the C5 programming been changed?

 

[aussiegold]

fuel pump has been changed with a known good one. the original had a slightly perished diaphram. no difference.i have ruled the C5 out because i swapped it all back to DYNA. coils and points replacement module. here is a picture of a fuel bowl gadget i knocked up.
hopefully , ( when the JB Weld sets ) i will use it and see how much fuel the bowls are holding. should also be able to see if the float valves are letting fuel in and shutting off properly.
as far as the other carb racks go......i just dont know... :headscratch:

 

[joedrum]

opcorn: :yes: opcorn:

 

[aussiegold]

here are some pictures of the fuel levels in the fuel bowls. and this is the way i tested each carb.

turned fuel tap off
drained fuel bowl and fitted the clear hose.
turn fuel tap on, start engine and watch hose fill . let it run a few mins and take a picture.
( on cylinders 2,4, and 3 the revs pick up slightly as bowl fills to running level. no change on cylinder 1 )
turn fuel tap off, turn engine off and drain fuel bowl into small bottle. take a picture of the measurement.
turn fuel on, restart engine and watch fuel level in the hose again.
drop clear hose into a container with engine running. lift hose and watch fuel drop to normal level.
turn fuel tap off , see fuel level drop, turn fuel tap back on and watch fuel return to running level.
did this twice on each carb.
i have no idea where the level is supposed to be. this afternoon i will measure the fuel in my LTD carbs, to give me an idea. the fuel levels in all these ,looks high to me.

 

[joedrum]

well if there is gas in bowl and seems to work right..then idle circuit has to be pluged enough to not drew gas in at idle ...later in rpm the secondary and main jet kick in and it probably runs ...its one thing to get jet cleared ...its entirely different to get passages clear ..these stock carbs have very small passages and 90 turns in them also ...hmmmmmm need a micro roto rooter for some of these carb racks ...what else can it be hmmmm

 

[slabghost]

Not certain on these carbs but on other cv carbs the fuel level should be 1-2 mm below the top of the bowl with bike level. So to me they all look a bit high.

 

[dan filipi]

Hmm, too high gas in the bowls can cause an over rich condition also.

Could it be it's running too rich when you feel the surging?
Could it be the one spark plug that appears lean, is the only cylinder that's burning properly, the other 3 too rich?

 

[slabghost]

Could be it runs right under acceleration because the bowls are still filling but at steady throttle they overfill and return to normal. Cycling like twisting the throttle back and forth.

 

[aussiegold]

i will get to the bottom of it, eventually. it looks like , so far, the idle circuit on no 1 is not functioning. that could be for a couple of reasons.
a blocked passage, ( i know the jet is clear) or maybe the bowl gasket is not sealing the idle circuit. ( one of it's functions )
or, ( most unlikely ) there is a massive air leak on that carb, letting it suck air in, enough to prevent the idle circuit to work correctly.
have taken a couple more pics, just to document the process.
first is a spare fuel bowl with the exact amount of fuel thats in the four carbs.
second is that bowl with the floats in. i know that's not indicative of how it runs, but it shows that amount of fuel is not too much.
third ( to prove that theory ) is a picture of the clear tube on the LTD ( running )
and lastly is the LTD fuel bowl , measured in the little bottle. ( some may have noticed it is a different colour to the fuel in the blue bike. it is 95 octane, the blue bike has standard unleaded )
so, i am satisfied that the float levels are right on my blue bike. and , that the float valves work as they should. next, is to take the rack off again and attack that number one carb. :salute: ( again) :Egyptian:

 

[slabghost]

Did you check the fuel level with the floats pushed down to the level of the bowl tops? Look how much higher they are just floating unmounted.

 

[aussiegold]

slabghost » Tue Oct 07, 2014 5:10 pm[/url]":1ctnai08]
Did you check the fuel level with the floats pushed down to the level of the bowl tops? Look how much higher they are just floating unmounted.

yes i did... until i remembered that they float... :smilie_happy:
i am off to Adelaide for a few days work. this pile of crap will have to wait a while. :head bang: