Carb problems

[jonesy_NC30]

k team a brief history on whats happened so far.

vfr400 nc30
V4, 4 carb

over the last year i have had the bike its been a right royal bit*h to start cold.
-choke has done stuff all not been able to start it with it on, and when its put on when running its bumped up the revs a tad, and rough running
-running realllllllllllllllyyyyy rrrrich, even when hot
-running good

last weekend
off came the carbs,
-bottoms off, jets cleaned out, made sure correct jets and needles are in correct carbs (front and rear carbs)
-still running factory main jets
-choke linkage adjusted to max travel
-noticed the pilot screws were all 3.75 turns out (specs say 2.5) changed to specs
-didn't separate the carbs
-plugs out cleaned, gap checked, look near new

didnt check float heights, nor pull apart the choke internals nor balanced them (feel like a twit now for not doin it)

now the bike
-bit*h to start when cold (maybe a tad easier to start) unable to start with choke
-when hot it starts 1st go or out in the sun in the afternoon
-when started cold and try and give it choke it fully dies, also when hot
-high gear low revs, give it sum stick and it cough abit then slowly revs a bit then takes off
gives me the impression its running lean


now its time to pull them off again.

any ideas??

guessin i should pull the choke internals apart and clean them out

balance the carbs
-anyone able to help out with the bench top or drill bit method (hear of them unsure tho)
thinking of changing the pilot screws to 3 turns?

any other ideas?????????

cheers all


any CHCH bike mechanics that do cashies?

[Akzle]

just as well you censored the word b*tch.




cos shit like that really fucks the mods off.

http://bsa.govt.nz/publications/rese...n-broadcasting

[caseye]

It does not too, fuck ya Akzle you "bitch".
LOL, now go on and tell the nice budding motorcycle mec an ic what to do next instead of being so darned worried about some mods.
Right track! Carbs off again, find out why yer choke ain't working, probably find it's all interconnected and once you sort that it'll all smooth out.

[Akzle]

fuken balancing the cunts would be a good start.

[Drew]

Carbs off again, find out why yer choke ain't working, probably find it's all interconnected and once you sort that it'll all smooth out.

You might be surprised, just how unlikely it is to get one of those Vf fours to run smoothly through the rev range.

I don't know how to sort it sorry. I know a bunch of people that have tried and couldn't get it right. They reach a certain age and just can't be set up for one reason or another. I think wear on parts, allowing air and fuel to go where it shouldn't.

New emultion tubes and needles to start. In fact, all the brass inserts in your carbs couldn't hurt. You would probably spend less time in the end, to get an Ignitec injection system and have someone set it up for you.

I know that sounds dumb, but they are cheap and a few guys from on here are putting them on their race bikes. They tell me buckets are real race bikes.

[jonesy_NC30]

fuken balancing the cunts would be a good start.

anyway of doin it without the vacuum tool?

float heights??

[Drew]

anyway of doin it without the vacuum tool?

float heights??

Float levels are pretty easy.

Balancing isn't too hard. A piece of hose is all you need. One of the butterflys is direct connected the throttle cable wheel at the carbs. Place the hose at the bell mouth with the motor running, and listen. Then move to the next butterfly in the sequence to that and repeat. There's an adjustment screw that is spring loaded. Make the sound of the two match with teh hose at the exact same spot on the bell mouths, and then move onto the next one.

It's fiddly, but you would be surprised how close to spot on can be achieved.

[Akzle]

anyway of doin it without the vacuum tool?

float heights??

you, son, need a motherfucking manual.

Carbs can be bench syncd (you mentiond drill bits?)
by looking up the snout and twiddling knobs till the butterflies look the same in relation to the bypass/idle circuit holes.

Then ride it to some nigger with a manometer and do it proper like.

[jonesy_NC30]

Float levels are pretty easy.

Balancing isn't too hard. A piece of hose is all you need. One of the butterflys is direct connected the throttle cable wheel at the carbs. Place the hose at the bell mouth with the motor running, and listen. Then move to the next butterfly in the sequence to that and repeat. There's an adjustment screw that is spring loaded. Make the sound of the two match with teh hose at the exact same spot on the bell mouths, and then move onto the next one.

It's fiddly, but you would be surprised how close to spot on can be achieved.

o yep so the screw with the springs would be circled?

[Akzle]

o yep so the screw with the springs would be circled?

you need to balance one bank, then bring it in with the other

[Drew]

o yep so the screw with the springs would be circled?

Yep. The one without a screw is your baseline.

you need to balance one bank, then bring it in with the other

Yep. Balance the two side by side, front and rear. Then a front and a rear with the linkage adjuster.

[Taxythingy]

Then ride it to some nigger with a manometer and do it proper like.

Presumably a manometer will just read zero, given it's a Honda.

[Akzle]

Presumably a manometer will just read zero, given it's a Honda.

shit. It escaped my notice.
He'll need a fagometer then. Altho itd probably go off the chart....

[splatcat]

well its taken me awhile to sort out my vf700c and carbs can be tricky but once youre done it in correct order they are sweet.
not sure what type of carbs you have on yours or the system .mine had cali emissions control on it but all sorted now.the idle screws wind out for more fuel in for less.
if can help let me know .pic of area with question will help best i can .
cheers

[splatcat]

k team a brief history on whats happened so far.

vfr400 nc30
V4, 4 carb

over the last year i have had the bike its been a right royal bit*h to start cold.
-choke has done stuff all not been able to start it with it on, and when its put on when running its bumped up the revs a tad, and rough running
-running realllllllllllllllyyyyy rrrrich, even when hot
-running good

last weekend
off came the carbs,
-bottoms off, jets cleaned out, made sure correct jets and needles are in correct carbs (front and rear carbs)
-still running factory main jets
-choke linkage adjusted to max travel
-noticed the pilot screws were all 3.75 turns out (specs say 2.5) changed to specs
-didn't separate the carbs
-plugs out cleaned, gap checked, look near new

didnt check float heights, nor pull apart the choke internals nor balanced them (feel like a twit now for not doin it)

now the bike
-bit*h to start when cold (maybe a tad easier to start) unable to start with choke
-when hot it starts 1st go or out in the sun in the afternoon
-when started cold and try and give it choke it fully dies, also when hot
-high gear low revs, give it sum stick and it cough abit then slowly revs a bit then takes off
gives me the impression its running lean


now its time to pull them off again.

any ideas??

guessin i should pull the choke internals apart and clean them out

balance the carbs
-anyone able to help out with the bench top or drill bit method (hear of them unsure tho)
thinking of changing the pilot screws to 3 turns?

any other ideas?????????

cheers all


any CHCH bike mechanics that do cashies?

the nuts on choke screws ( enricher needles) must only be finger tight as needles will not reset in place when choke off causing flooding and will run like crap. yes you should of bench syn carbs with a thin shim strip. use main idle screw to set up and down. idle mixer screws start at 1 7/8 turns out .
then do rev down system to set final air mix.hope that you check all diaphragms for holes and that main jet barrels move smoothly up and down .diaphragms are lined up with vac holes and caps on correct way.
i wont be in chch till end of oct sorry to say.
cheers