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Carb Adjusting

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roguevfz1

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Got the carbs back together after having them cleaned (I didn't take them apart- pulled all the jets out, tops off, slides out & my buddy soaked them in a sonic bath, blew all the ports out & checked everything over, said they looked good. I know I took a shortcut there but didn't wanna go through al the springs & attachments this time.) & put new bowl gasket's & o rings on all the jets & 1 choke plunger that had the end broken off that attaches to the #1 carb that the previous owner rigged with a hanky plate & zip tie. New plugs, fuel filter, air filter was nearly new, drained the radiator & runnin 50/50 distilled water & white vinegar for a good flush while I sync & adjust the carbs.

I bench set the mixture screws @ 1 turn out & didn't touch the idle speed cable screw at all. It ran pretty good @ around 1k after warming up before I pulled the carbs. I haven't fully adjusted the cable ends @ the carbs as the service manual says to sync the carbs 1st, left that for after. I also need to get a angle screw driver to set the mixture screws Please suggest which 1 is economical & works well!

It started right up with full choke after I cycled the fuel pump a few times & made sure I saw fuel go into the new fuel filter. When I started to let the choke off, it seemed like idle was low so I turned the adjuster a bit to get it to idle around 1k. But then when I turned the throttle grip a little bit, it either died or did some popping out the exhaust. Started it again & it revved a little with a twist then stayed up around 3k so I shut it down. Now it won't allow me to twist the throttle at all. What's the next step? I will say that only riding it twice, I didn't notice how much the grip twits to get to full throttle, but now it only twists about 1/5 of a turn before it hits the stop. Seems like I may have either something binding the throttle cables @ the carbs or I'm just not used to how short a throw this bike's throttle has. Both cables @ the carbs have the nuts run all the way back to give it as much play as it needs & there's virtually no play in the grip.

Thanks in advance for any thoughts.
 
The Gen 1s have 1/4 turn throttles so it sounds like that’s not the issue. I thought the mixture screw settings were suppose to be closer to three to 5 turns out. 3 for stock and closer to 5 for jetted i.e. Ivans

The issue of not being able to transition from choke to throttle may be related to the carbs being out of balance. I’ve had similar issues with needing to turn up choke after carb rebuilds and that was the problem.

It could be that at only one turn out the carbs are starved for fuel…. requiring the choke.
 
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Start with checking the throttle cable connections on the carbs and routing.
For the carbs, apparently the brass covers were already drilled out on the carb bottoms as you could adjust the A/F screw? By chance did you note what size jets were in the carbs as it could also impact the A/F settings.
1 turn out is most likely the issue. I'd go back and set at 2.5 turns out for each and try that.
 
Eff-Zed-1 said:
Start with checking the throttle cable connections on the carbs and routing.
For the carbs, apparently the brass covers were already drilled out on the carb bottoms as you could adjust the A/F screw? By chance did you note what size jets were in the carbs as it could also impact the A/F settings.
1 turn out is most likely the issue. I'd go back and set at 2.5 turns out for each and try that.
Click to expand...
My buddy who did the cleaning pulled the brass cover out for me as they were still in.

I need the proper angled long screwdriver to set the screws now as I don’t wanna go through taking the carbs back out to set the screws. Looking into that now. Thanks.
 
This looks like the 90-degree screwdriver that I used for my Gen I. It can get in to the mixture screws easily. slight pressure on the bit end and slowly turn the knob, and you'll fee the bit go into the screw. After it's in the screw, one turn on the knob is 1 turn on the screw, so it was easy to work with.

Bevel screwdriver on Amazon
 
Blue Flash said:
This looks like the 90-degree screwdriver that I used for my Gen I. It can get in to the mixture screws easily. slight pressure on the bit end and slowly turn the knob, and you'll fee the bit go into the screw. After it's in the screw, one turn on the knob is 1 turn on the screw, so it was easy to work with.

Bevel screwdriver on Amazon
Click to expand...
Mine is not this fancy! It'll be here tomorrow. Mixture screws should be nice & clean so I don't expect any binding there so my less powerful screwdriver should be fine. I'll keep you all posted. Will start with 3 1/2 turns out then sync & see how she responds. Have to tune an 81 BMW R100 RT 1st. Keepin my sticks active these days!!
 
Blue Flash said:
This looks like the 90-degree screwdriver that I used for my Gen I. It can get in to the mixture screws easily. slight pressure on the bit end and slowly turn the knob, and you'll fee the bit go into the screw. After it's in the screw, one turn on the knob is 1 turn on the screw, so it was easy to work with.

Bevel screwdriver on Amazon
Click to expand...
Hey. My screwdriver just came in. It looks exactly like yours without the attachments. I did #1 & 2 carb easily. The bit in mine is too short for #3 & 4 carb, as the timing chain adjuster is in the way of a straight in approach and angled up above the timing chain adjuster doesn't catch the screw, so I need a longer bit & looks like the kit has the longer bits & adapter to insert them into. Does your driver ratchet a little too? I pulled mine apart & shot a little chain lube in the end piece but doesn't seem to make a difference, still ratchets a little. Just wanna make sure that your driver IS the 1 in the picture or if it's a different 1. My driver feels pretty cheap. Here's the link to mine; https://www.amazon.com/dp/B0CND328NG?ref=ppx_yo2ov_dt_b_fed_asin_title

Let me know your thoughts. Thanks.
 
That looks very similar to the one I used. I don't remember it ratcheting or slippin, though.
I think I Thad to tip it a bit too get it into the "tunnels", but I didn't have issues with engagement or slipping.

It seemed to have olenty of reach. Did you put a finger under the shafts to hold it on the screw? That should get it to reach the screw.

Maybe a standard drill / screw bit just a tad longer could reach?
 
Blue Flash said:
That looks very similar to the one I used. I don't remember it ratcheting or slippin, though.
I think I Thad to tip it a bit too get it into the "tunnels", but I didn't have issues with engagement or slipping.

It seemed to have olenty of reach. Did you put a finger under the shafts to hold it on the screw? That should get it to reach the screw.

Maybe a standard drill / screw bit just a tad longer could reach?
Click to expand...
The angle I have to get it into 3 & 4 just doesn't allow the bit to fully engage with the screw & I don't have the option to change bits like yours does.

I'll return mine & get the 1 you posted & see if that works.
 
Rogue, I’ve had similar issues with the most expensive of these screwdrivers (Motion Pro). I actually had better success on carbs 1 thru 3 using a small ignition screwdriver with 75% of the handle cut off so it’s about 2 1/2” long. #4 carb is tough no matter what you use. For me it was knowing I was fully seated in the carb’s adjusting screw. I would have to fully close each screw each time to make sure I had the turn count right.
 
Isleoman said:
Rogue, I’ve had similar issues with the most expensive of these screwdrivers (Motion Pro). I actually had better success on carbs 1 thru 3 using a small ignition screwdriver with 75% of the handle cut off so it’s about 2 1/2” long. #4 carb is tough no matter what you use. For me it was knowing I was fully seated in the carb’s adjusting screw. I would have to fully close each screw each time to make sure I had the turn count right.
Click to expand...
Yea, I needed up trying a Stihl carb adjusting screwdriver to do 3 & 4 but didn’t work as I can’t get my hand in there far enough to turn it.

I’ll see what this new screwdriver with longer bits does. Should work.
 
Blue Flash said:
This looks like the 90-degree screwdriver that I used for my Gen I. It can get in to the mixture screws easily. slight pressure on the bit end and slowly turn the knob, and you'll fee the bit go into the screw. After it's in the screw, one turn on the knob is 1 turn on the screw, so it was easy to work with.

Bevel screwdriver on Amazon
Click to expand...
Got the 1 you mentioned from Amazon yesterday. It's really a piece of crap! Maybe it's just me being used to using quality tools, but as soon as I tried the fixed screw bit end, it wasn't long enough to # & $, so I pulled it apart to attach the apadater to fit the other bits & it was horrible! Ratchety & wouldn't turn well @ all! I pulled it apart again, greased the bit end & that was no help. The gears in the adapter end are not well machined.

Anyway, The other problem with this tool, as I tried it before pulling it all apart, is that the longer bit do not fit in the barrels of the mixture screws. They are the same size of the barrel, causing the driver bit to bind on it, not allowing you to turn the screw. I needed up pulling the carbs back off (as I'm now becoming an expert!!!), and checking the mixture screw turns. Thats when I found out the screw bits don't fit. I took them to the grinder, found them down on each side of the salt end, including the barrel deep enough to go into the car barrel & voila!! They fit well! Got the handle, inserted each bit to check they worked & they did!

I'll be buffing out the gear on the adapter so it will not be ratchety. I'll post the update after!
 
So, after setting all the mixture screws to 3 turns out, not syncing the carbs, TPS not fully adjusted & slightly loose in its position before I started this & the cable adjusters still a bit loose, I started the bike. Full choke keeps it running @ around 1k rpms.

As soon as I try to crack the throttle the least bit, it stalls, no matter how warm I let it get. There's a small coolant leak that's dripping from the center of the engine right down onto the header that I have no idea where that's coming from, but needless to say, I didn't let it get very hot. I have 50/50 dislled water & vinegar in the system to flush it. Checked all the carb fitting for coolant & they aren't leaking, from what I see.

Is this happening from not syncing the carbs before trying to throttle up or is 3 turns out on all stock jets with a cheap slip on causing this? The bike ran pretty well when I test rode it but needed to fully warm up before it ran well. I thought that was from sitting so long & carbs got gummed up.

I'm also going through Pat's notes on all the carb stuff to see if anything there tells me something I've either skipped or overlooked. Nothing yet but still reviewing.

Any help is appreciated!
 
roguevfz1 said:
Got the 1 you mentioned from Amazon yesterday. It's really a piece of crap! Maybe it's just me being used to using quality tools, but as soon as I tried the fixed screw bit end, it wasn't long enough to # & $, so I pulled it apart to attach the apadater to fit the other bits & it was horrible! Ratchety & wouldn't turn well @ all! I pulled it apart again, greased the bit end & that was no help. The gears in the adapter end are not well machined.

Anyway, The other problem with this tool, as I tried it before pulling it all apart, is that the longer bit do not fit in the barrels of the mixture screws. They are the same size of the barrel, causing the driver bit to bind on it, not allowing you to turn the screw. I needed up pulling the carbs back off (as I'm now becoming an expert!!!), and checking the mixture screw turns. Thats when I found out the screw bits don't fit. I took them to the grinder, found them down on each side of the salt end, including the barrel deep enough to go into the car barrel & voila!! They fit well! Got the handle, inserted each bit to check they worked & they did!

I'll be buffing out the gear on the adapter so it will not be ratchety. I'll post the update after!
Click to expand...
Hmmmm.... Well, I bought mine 20 years ago, and the one on Amazon really does look just like mine in the pics. It worked great - I loved that one. Sorry this one didn't work out!
 
Checked up on Pat's page for specifics on carb syncing.

I attached my CarbTune sticks & started the bike. Used about 1/2 choke to keep it running & idling around 1500. After a couple mins as it started to increase in idle speed, I lowered the choke a little. No readings on the sticks yet. When I revved it a tiny bit, it increased to about 3k rpms, the sticks finally registered; 1-3 were around 23-26 & 4 was around 5. I let the choke all the way out & the bike stalled. Put a little choke on & started the bike again. Idled around 1500 again & no readings on the sticks @ that low rpm. The idle adjusting knob doesn't seem to do anything to increase or decrease the idle @ all?? I never touched that cable when removing or cleaning the carbs. Why does it not adjust the idle speed?

I also checked the TPS position. Put it into setting mode & tach read 10k. I moved the TPS both ways to full stops (not that it moves all that much) & it didn't change the tach reading at all. Could the TPS be bad?

Starting to wonder what I'm missing?? I've owned & worked on many bikes with success with every 1 of them but this perplexing! Feelin a little lost here!
 
The idle adjusting knob should be making a difference. Any chance one of the carb balance springs fell out? Not easy to see them with carbs installed. It does sound like not all four carbs / cyl are pulling evenly.

The TPS is really for fine tuning. You could loosen the TPS set screws and move it to it’s stops in both directions while riding and you wouldn’t notice much difference.

Using the choke all the time could have fouled a plug. Have you tried adjusting the balance screws. I know you're not at the recommended RPM for setting them but you need to get them closer than you’re reporting.

Per your PM my Wizard distinction just means I’ve posted a lot……... so more about quantity than expertise.
 
Isleoman said:
The idle adjusting knob should be making a difference. Any chance one of the carb balance springs fell out? Not easy to see them with carbs installed. It does sound like not all four carbs / cyl are pulling evenly.

The TPS is really for fine tuning. You could loosen the TPS set screws and move it to it’s stops in both directions while riding and you wouldn’t notice much difference.

Using the choke all the time could have fouled a plug. Have you tried adjusting the balance screws. I know you're not at the recommended RPM for setting them but you need to get them closer than you’re reporting.

Per your PM my Wizard distinction just means I’ve posted a lot……... so more about quantity than expertise.
Click to expand...
I didn’t take the carbs apart from each other or remover the idle adjusting cable when I did the cleaning. I just took each float bowl, jet, float needle & floats, slide out. My buddy removed the mixture covers & mixture jets out, put them in a sonic cleaner & cleaned them. All the springs were left in place that connect the sync screws & springs, so all should still be working properly, unless something was wrong with them from before.

I took the TPS sensor out of the right carb before he soaked them. When I reinstalled them, I put the sensor back in & positioned it on the same mark that they were in before from the screw mark on them.

I’ve only started the bike a few times since they were clean & new plugs went in then too. Not sure a plug could be fouled with just the little starting I’ve done so far.

I’ve only just put the sync sticks on the last couple times of starting the bike & not really getting a reading @ 1100-1500 rpms. The tubes for the sync ports well. Don’t think there’s any leaks there. It only registers a cull at higher revs. Weird, right?

I’m thinking that my early shortcuts of not taking out the choke plungers & separating the carbs for cleaning may be something I need to do to insure that all pathways through each carb is done properly. I only have a solvent dunk take that can soak 1 carb @ a time, but I see in the service manual that solvent soak is not recommended. I guess that’s because of some of the plastic parts? Pretty sure I broke them down to the point there’s no plastic left in them.
 
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