Follow up on carburetor\1st gear\petcock problems

Hello, this is a follow up for these two posts

http://www.gtamotorcycle.com/vbforum/showthread.php?191343-Rough-1st-gear

http://www.gtamotorcycle.com/vbforum/showthread.php?191205-Petcock

I adjusted cable on the engine side for my clutch, that did not change a thing, therefore I would assume its time to change this cable. Tell me if I am wrong.

Now about the engine dying while idling with choke fully on(or off, which ever one is the one that you suppose to put it in when the bike is warmed up) - forum suggested to clean carburetor, I asked for a favour from my friends dad - he is a pro mech(for cars only), we spent over 1.5 hours taking the bike apart - had to remove all sidings, mirrors, fuel tank and such. When we took carb apart, it was pure inside - no indication of dirt or anything, he said it looks brand new(probably previous owner cleaned it before sale). Therefore choke problem is not triggered by carburetor, neither it is the air filter, as we looked at it and its brand new. So my question is, what could the problem be? I have 3 pairs of hands, 1 with lots of experience(OVER 30 YEARS, but cars), but no idea what to look for, as he says its usually air filter or carb...

Anyone?

I am not sure how you determined the carbs are clean, hopefully you checked all passages, jets, etc, there are some very tiny passages, just big enough for a piece of wire say from a wire brush to allow passage only so a good magnifying glass will aid to make sure all are clear

have the carbs been syncd ?

How ow were they cleaned in the past, a full tear down, and dipped or ultrasonic cleaning ? Or did some one just spray carb cleaner where they could and called it clean

have the o rings been changed are they all good

your bike is a bit newer for this site

http://www.thegsresources.com/_forum/forum.php

but the guys might help as for carb cleaning you can look here depending on your carbs

http://members.dslextreme.com/users/bikecliff/

carbs bs can be a pain,

does the the bike even idle, or it just stalls out

choke is usually need for initial startup, after 1-2 minutes it should not be needed any more, longer sometimes as the weather gets colder

here are my carbs taken apart for cleaning




And a different set

I have no information in regards of how there were cleaned, but when we took them apart, they looked pure, like new carburetor looks. We did not clean them however, perhaps we still will Tuesday. Everything there looks clean and in good condition, no tears or anything.

It does idle for roughly 20-30 seconds and dies, but even when you ride with choke in 10% of position, it jumps, its not a clean acceleration.

Also, where did you find the tool to sync? I cant seem to find it in any store, and paying 125$ + delivery for 1-2 time use tool, seems to be too much

make one.
http://www.powerchutes.com/manometer.asp

I'm a little unclear on what fault is attempted to be remedied here - it appears to be nothing related to the two originally linked threads but instead a warm-idle stalling problem. (Or is it a cold-idle stalling problem but you are taking the choke off too soon? Is it OK once the engine is fully warmed up?)

Explain ALL symptoms. Explain the timeline. Explain the sequence of events that causes the symptom to be displayed. The slightest detail that seems meaningless to you can be the tipoff to what the real problem is.

Anyway, IF the problem is stalling at warm idle ...

Slightly out-of-synchronization carburetors will not cause this. Grossly out-of-synchronization carburetors, to the extent that this 4 cylinder engine is only trying to idle on a couple of them, can cause this but will coincide with having a very rough-running engine just off idle (smoothing out as the throttle is opened more than just a fraction with the engine under load). If you have a dead cylinder but can get the engine to stay running at idle (raise the idle speed using the manual adjustment if needed) you can tell which cylinders are weak by taking a damp cloth and touching it to each exhaust pipe.

Carburetors in the late part of their era (includes yours) were frequently set up very lean at idle and just off idle, for emissions reasons. It doesn't take much being out of whack before it goes too lean to fire. If this is the situation, it will be worst after the engine is off choke but before it fully warms up. A lot of these engines want to have the choke left a little bit on for quite a while until the engine is warmed up. If this is the situation then the bike will likely benefit from having the carbs rejetted. It could be as simple as an extra half or one turn open of the idle mixture screws.

The carbs could be completely clean but out of spec: idle mixture screws too lean, float level out of spec (probably too low), etc.

Incorrect valve clearances, worn-out spark plugs, bad plug caps, tired engine with low compression are all non-carb-related things that can cause rough running, hard starting, stalling, etc.

Speaking of which, what do the spark plugs look like ...

shadowelement said:

Also, where did you find the tool to sync? I cant seem to find it in any store, and paying 125$ + delivery for 1-2 time use tool, seems to be too much

Click to expand...

I borrow one from my buddy, but he got his here - http://www.carbtune.com/

or as mentioned you could make one, I have never tried them

and

Brian P - is spot on with his comments.......

Hello Guys! My friends and car mech are coming over at 6-7pm, we will try doing all the suggested things.

From what I was told by previous owner, spark plugs were cleaned previous year, but will take a look at at them today.

Now to the details - after I start the engine will choke fully on, it starts at 2000 rpm and in less then 3-4 seconds jumps to 4-5-6 rpms, after that I move choke to 50% position and let it rev at 2500-3000 rpm for about 2-3 min, if I turn choke off, it will idle for roughly 10-20 seconds with visible rpm jumps and light panel blinking and die out.

Not sure about dead cylinder, I only have 1 exhaust, so perhaps I am misunderstanding you - how would I check each exhaust?

I don't like to clean plugs, I will buy new ones, make sure they are gaped correctly and install

so from what your describing it sounds about right, full choke on, start bike, runs at high rpm, you lower choke, rpms go down, so far so good, until you have no choke on at all, it then stalls

not sure what panel light is blinking, you don't say

so you could have a low idle set, can you increase the idle speed, if and when it does idle, what is it at, you should probably be around 900-1100 rpms for your idle ( just a guess )

something could still be clogged, floats are not set right, kinked fuel tube, petcock not working right

try to put the petcock on prime and start the bike and does it still die as you mention above ?

you have a 4-1 exhaust ?, but each cylinder has it's own down pipe, are they all warm or hot to the touch ( don't burn yourself ) you can tell if one pipe is hotter or colder than the rest

the joys of old bikes.......

Still sounds like your pilot jets. You sure they weren't obstructed? The hole is ridiculously small in those. I would soak them in Pine-Sol overnight and try again.

shadowelement said:

Not sure about dead cylinder, I only have 1 exhaust, so perhaps I am misunderstanding you - how would I check each exhaust?

Click to expand...

Look at the front of your engine, not the back ... I think you had better farm this job out to someone else.

And or poke all the holes with a wire......to make sure there is nothing in them holes

I have some Berryman dip for cleaning carbs and carb parts, you bring the parts over and we can let them soak for a 24 hour period,,,,,the Pine-Sol might work for you as well....

I can buy new plugs, as long as I am certain they are the issue, but once again, will take a look at them when home.

As what goes to idle rpm with choke fully off - under 1000 rpm

I bought a carb cleaning spray, so I can soak parts of it in there, perhaps that will help, but from what we saw yesterday - its pure, like very very clean. But I guess we can do it again.

I will try to put petcock to prime when I am home and see how will that work.

As what goes to brining the bike to shop, I would have already done so, but for that I need to put plates on it, for that I need safety and for that I need to bring the bike to the shop...I dont have a trailer and I really don't want to pay 100$ one way for a delivery. Maybe someone knows affordable mobile mech?

Buy new plugs, it's not a lot of cash, but your at least certain for the most part it won't be a bad plug

under 1000 rpm at idle sounds low, turn up the idle to about 1100 and tell us if it still stalls out

carb spray and spraying it will do almost nothing, proper carb cleaning is a full strip down, soak in Berryman's, Pine-Sol, and or an ultrasonic cleaning, all rubber O rings get replaced unless they are pristine, all holes are inspected and a wire is pushed through each and every hole, you then have clean carbs, you then set float level, bench sync the carbs, install, get bike running and do a carb sync

petcock on prime will just let us know if the bike is stalling due to starvation of fuel, prime will just let the gas flow freely, you can also hook up an IV bottle to the carbs directly so that you have fuel flowing without any restrictions

as for getting the bike to the shop, U-Haul bike trailer is 15 bucks for the day, assuming you have a vehicle with a hitch or a buddy with one.....

If you were close by, I give you a hand on the carbs and such, but it seems you are not so close to me....

Okay, well I guess we will have to wait till evening and then I will have more information!

As what goes to Pine-Sol and such, I can purchase them no problem.

I am located at Keele and Rutherford, which is right beside Wonderland. I am ok with paying someone who can fix and show me things I need to know (as again - new to this). Sadly I have no cars with hitch, all my friends drive either sport cars or small town cars...

one bottle of Pine-Sol and one bucket of hot watter, 5 gallon pail will do, remove the diaphragms and toss the entire assembly into the bucket make sure all is covered and under the solution, pull out in 24 hours, rinse with hot water, reassemble and try again

get a U-Haul van then, put bike in van and take to shop....just a suggestion....







even after the soaking, there was still crud in the bowls that needed to be removed



The Berryman dip, well that you can only get in the US

I have trouble removing one of the cables, its seems to be locked somehow, if I deep it with the cable, that should not damage it?

And just to make sure, this is the picture of the carb.

The cable will probably not get damaged at least not by Pine-Sol, it should come off, but I can't see by your picture how it's in place so I can't tell you how to remove it

remove the diaphragms as in my first picture, you don't want them soaking

so all those brass jets should be removed and inspected to make sure they are clean, to make sure all the O rings are in good order, as well as the float height is to where it needs to be...

there is a lot of work on carbs, take your time, take lots of pics on how things are and where they go, or do one carb at a time, and if your unsure of anything, take them to someone who will do them correctly

Good luck

Given that you have a rack of four carburetors assembled together, I would strongly recommend that you not disassemble the carb bodies from the linkages and crossbars that hold them together. Do not disassemble this unless necessary.

All that really needs to be done, once you have the float bowls off, is to unscrew the slow (pilot) jets and make sure they are clear, then blast the holes that they are screwed into with parts cleaner solvent. When you do this, you can easily confirm that fluid is passing through the idle screws and the transition slots/holes.

Hello Guys!

So this happened, we took the carb out and started looking at it and figuring out how we would clean it and so on, but as soon as we start taking out the jets, one of the pilot jets broke inside...we had to wait for my other friend to come with a special tool to take it out, as we were afraid of damaging the carb. We did took it out, but since I didn't have any spare jets we could no longer continue our work on carb. I will be ordering jet tomorrow, it should be here this Friday.

Since we had a lot of spare time, we decided to take a look at sparks - here is where our opinions clashed - some said that sparks look ok, some said they need to be changed, I am all about changing them, as one of them is looking way darker then others (pics attached). That I will buy tomorrow.

This being said, we also removed the rear fender and installed custom lights, however this had nothing to do with performance, but since there was nothing we could do at spare time, this seemed like a good use of time.