carb problem?

[vmaxinID]

So did it spark?

 

[trickster]

yes like ba good un!.....lol:rofl_200:

 

[johnpclynch]

is your butterfly opening on that carb?
could it be a carb linkage problem?

 

[trickster]

thanks
but all seems ok mate
cheers
rick
alls working but backfire is there!

 

[06VMAXIMUS]

Did you sync the carbs?

 

[johnpclynch]

I don't think the issue is with your carb, if there's a vacuum being produced then the slide should open (regardless of fuel/blocked jets)
It looks like you are loosing alot of vacuum (not just through worn rubber seals) or not getting any at all and you have exhaust deposits (maybe even flames) all the way back up to the carb!
To me it can only be a problem further down maybe with valve clearances/stuck valve/holed piston (in ascending order of $$$)

 

[deekjx]

is your butterfly opening on that carb?
could it be a carb linkage problem?

Well it seems that what I was hearing was backfire through my carbs. I can see the smoke lingering in over the carb once I turn the engine off. For me its actually the carb on cylinder 1 not 3. Something I noticed with my issue was the choke setting triggers it. When I look at the choke linkage, the choke is opening on that cylinder well before the other three. That cylinder ends up getting more air than the others when I open my choke. My intermittent nature of my issue may have to do with engine temperature. because once the engine is warmed up, it doesn't seem to happen anymore. I can only reproduce it on a cold engine. There is a screw that connects to the rod that opens the choke on that carb that I can adjust and I'll do that. Hopefully my trouble is over and it really wasn't something serious for me. :eusa_dance: I think I'll do the shotgun on my carbs today while I have access to them.

This clearly isn't your problem trickster as I don't think the choke matters in your case. Let us know how the compression test goes. Hopefully its not the engine.

 

[PATMAX]

D, wear eye protection when shooting the cleanet through the circuits/openings. Don't ask how I know this is important!

 

[jfeagins]

deekjx - there shouldn't be any adjustment for only one carb choke at a time. Seems the linkage rods have small indentations in them from the factory. The set screw for each carb choke should sit down into the corresponding indentation. Only one way to assemble - and the only way to get one outta sych with the other 3 chokes would be if there's a screw completely backed out. Least ways, that's the way my 85 is built.

 

[deekjx]

deekjx - there shouldn't be any adjustment for only one carb choke at a time. Seems the linkage rods have small indentations in them from the factory. The set screw for each carb choke should sit down into the corresponding indentation. Only one way to assemble - and the only way to get one outta sych with the other 3 chokes would be if there's a screw completely backed out. Least ways, that's the way my 85 is built.

You are correct. Further examination of this linkage proves that. Carb 1's starter/choke when tighten returns to the exact spot it was before I started. When I adjust Carb 2's starter/choke, it actually tightens up into alignment with Carb 1. Now I have two carbs that open before the other two. The other two were properly tightened. I followed the linkage and saw that the connecting rod for the two sides was bent in multiple places. Clearly one of the previous owners did something to it. I had to adjust one of the bends to get carbs 3 and 4 to open thier starter/choke at the same time as carbs 1 and 2. Now they are all fairly synchronized. The back fire occurred at least twice after this adjustment. :bang head: It's difficult to say how much this has affected anything because its hard to duplicate when the engine warms up. I've started the shotgun process but just discovered my favorite precision screw driver doesn't reach into the hole to where the idle mixture screw is. Its off to the hardware store for me so that I can finish this procedure.

Edit: correction, seems a normal screwdriver fits so proceeding with the shotgun.

Edit2: Carb 1 has a hole in the diaphragm. Looks like the previous owner tried to repair it.





I take it that this would cause a vacuum leak, and be the source of my backfire for that carb. I'm going to try to repair it again so I can continue to ride but also look for a replacement to fix it.

 

[deekjx]

Patching the hole in my diaphragm took care of my issue.

 

[davesax36]

I left a comment on that video asking what the owner did to correct it. I wouldn't hold my breathe for a response though. He posted that a month and a half ago so if he does respond it might even be to say its still broke.

It's my video. sorry i've been busy with work stuff. I got everything running, but I think i have clogged pilot jets. No more backfire through carbs, though. I took everything apart again and put it back on. I'm pretty sure it's pilot and really bad sync. I'm going to have one more go at it, then it's off to a board member to actually fix things.

 

[deekjx]

It's my video. sorry i've been busy with work stuff. I got everything running, but I think i have clogged pilot jets. No more backfire through carbs, though. I took everything apart again and put it back on. I'm pretty sure it's pilot and really bad sync. I'm going to have one more go at it, then it's off to a board member to actually fix things.

No need to apologize and thanks for taking the time to respond to both the youtube video and the forum post. You rock unk:.

 

[trickster]

well thank s to all you guys on here for showing interest in my problem
just come back from a camping weekend she ran crap but she got me there and back
alot of talking at the camping, with like minded folks
it all points to valve promlem ?
all pots spark she will still motor along up to 75mph
when under load this soon drops and a lot of gear changes take place
all carbs are getting fuel
but nummber three pot is blowing up the carb
if you put your hand over the top of the carbs 1,2,4, you can feel them sucking air but on number four its totolly different its not sucking but BLOWING !!!!
so do you think that alls well but with the valve not sitting properly ][carbon build up or bent vavle][ its letting the [or small amount ] exhaust gas blow up the carb losing vaccume and popping?
just got to get my hands on a vaccume gauge to test the compression, will keep you informed
thank again
cheers
Rick

 

[trickster]

tester orded
does anybody know what the compression gauge should read so i have somthing to work to?
cheers
Rick

 

[jfeagins]

All four cylinders should test close in psi. Not sure how many psi, but know they should all test close to each other, with only minor, if any, variance.

In your case, I would think there's going to be a huge difference between the affected cylinder and any one of the rest of them.

 

[trickster]

i'll vote for that........lol

 

[trickster]

just thinking out aloud
does anybody know ,should i have to replace the rear head/valves has there been a change from 1985 to 2007 or are the "heads" the same?
thanking you
Rick

 

[trickster]

right i am realy puzzeled
compression tester came
tested the pots....number1...125psi.....number two....80psi....number..three[the problem
pot]....150psi.....number4....80psi
number2/4....low

 

[deekjx]

wow. How many times you test each one?

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