• Husqvarna Motorcycles Made In Sweden - About 1988 and older

  • Hi everyone,

    As you all know, Coffee (Dean) passed away a couple of years ago. I am Dean's ex-wife's husband and happen to have spent my career in tech. Over the years, I occasionally helped Dean with various tech issues.

    When he passed, I worked with his kids to gather the necessary credentials to keep this site running. Since then (and for however long they worked with Coffee), Woodschick and Dirtdame have been maintaining the site and covering the costs. Without their hard work and financial support, CafeHusky would have been lost.

    Over the past couple of weeks, I’ve been working to migrate the site to a free cloud compute instance so that Woodschick and Dirtdame no longer have to fund it. At the same time, I’ve updated the site to a current version of XenForo (the discussion software it runs on). The previous version was outdated and no longer supported.

    Unfortunately, the new software version doesn’t support importing the old site’s styles, so for now, you’ll see the XenForo default style. This may change over time.

    Coffee didn’t document the work he did on the site, so I’ve been digging through the old setup to understand how everything was running. There may still be things I’ve missed. One known issue is that email functionality is not yet working on the new site, but I hope to resolve this over time.

    Thanks for your patience and support!

Last question about 400 enduro (sorry)

cOrPsE

cOrPsE

Husqvarna
A Class
Sorry for spamming you guys with so many questions lol. So the bike is like 98% perfect. Everything is fine besides the fact it wont idle. It starts right up with the choke on (its cold here in MA).

So my step dad and I tuned the carb today and it would not idle no matter what we did. I noticed there is a lot of throttle cable slack. So we lightly adjusted it to not put much tension and all of a sudden the bike starts to idle PERFECT. Then i give it some gas and it fuckin FULL REVS. luckily i quickly got it to stop (kill switch wouldnt even work, although it normally does). Any tips? You guys have helped me bring this bike from death to glory so i appreciate it.
 
If you are running a Mikuni VM, there is an idle adjustment screw that will gently raise the slide to gradually increase your idle. You may have put a little too much tension on the cable and it may have stuck. You should check the ends(both) of the cable for fraying and replace. Cable are much less expensive compared to an engine rebuild
 
jimspac said:
If you are running a Mikuni VM, there is an idle adjustment screw that will gently raise the slide to gradually increase your idle. You may have put a little too much tension on the cable and it may have stuck. You should check the ends(both) of the cable for fraying and replace. Cable are much less expensive compared to an engine rebuild
Click to expand...

Yea its a mikuni vm. I tried that too and couldnt get it to work.
 
Don't want to insult you Corpse but the slide aint in backwards is it ?
Cutaway goes to the airfilter.

I have seen this done [ done it myself when I was a pup ] and the results sound like what you are getting.
 
No problem asking all the questions you want, however we do strive for a civilized level of discourse here; please refrain from use of the F word or similar :oldman: Its expected to say that in the garage while its revving like the starting line at the local MX track, but Im sure you can find a forum friendly translation in the future.

Thanks
 
Slacken up that Freakin' throttle cable to be sure you have plenty of slack. No, it's not possible to put the slide in backwards with a Mikuni...there's a groove machined into the slide that must line up with a pin in the carb body in order to slide down all the way.

Once you're sure you have no tension on the cable, then twist the throttle on/off quickly to make sure you can hear the slide returning freely (you'll hear a definite clunk). If not, it's binding up somewhere. Then, start the bike and keep the throttle grip part way open if needed to keep it from dying, the adjust the throttle slide stop screw (clockwise to increase idle) a little at a time to get your idle stable (all that screw does is to lift the slide a small amount....that same effect as twisting the grip).

After your idle is stable, only then go back to the cable to adjust out any slack (but do leave enough to allow about 1/16 to 1/8" play up at the throttle grip).

And after all that, then ride the "F"unny thing at various stages of load and no-load, and check the plug burn and adjust jets as needed (that's an entire separate discussion that goes way beyond this post).

And hey, don't fret asking multiple questions. Keep 'em coming until you've got her all figure out! That's what this forum is all about.
 
Old Geezer said:
Slacken up that Freakin' throttle cable to be sure you have plenty of slack. No, it's not possible to put the slide in backwards with a Mikuni...there's a groove machined into the slide that must line up with a pin in the carb body in order to slide down all the way.

Once you're sure you have no tension on the cable, then twist the throttle on/off quickly to make sure you can hear the slide returning freely (you'll hear a definite clunk). If not, it's binding up somewhere. Then, start the bike and keep the throttle grip part way open if needed to keep it from dying, the adjust the throttle slide stop screw (clockwise to increase idle) a little at a time to get your idle stable (all that screw does is to lift the slide a small amount....that same effect as twisting the grip).

After your idle is stable, only then go back to the cable to adjust out any slack (but do leave enough to allow about 1/16 to 1/8" play up at the throttle grip).

And after all that, then ride the "F"unny thing at various stages of load and no-load, and check the plug burn and adjust jets as needed (that's an entire separate discussion that goes way beyond this post).

And hey, don't fret asking multiple questions. Keep 'em coming until you've got her all figure out! That's what this forum is all about.
Click to expand...
It is possible to put it in upside down...don't ask me how I know this:-(
 
Old Geezer said:
Slacken up that Freakin' throttle cable to be sure you have plenty of slack. No, it's not possible to put the slide in backwards with a Mikuni...there's a groove machined into the slide that must line up with a pin in the carb body in order to slide down all the way.

Once you're sure you have no tension on the cable, then twist the throttle on/off quickly to make sure you can hear the slide returning freely (you'll hear a definite clunk). If not, it's binding up somewhere. Then, start the bike and keep the throttle grip part way open if needed to keep it from dying, the adjust the throttle slide stop screw (clockwise to increase idle) a little at a time to get your idle stable (all that screw does is to lift the slide a small amount....that same effect as twisting the grip).

After your idle is stable, only then go back to the cable to adjust out any slack (but do leave enough to allow about 1/16 to 1/8" play up at the throttle grip).

And after all that, then ride the "F"unny thing at various stages of load and no-load, and check the plug burn and adjust jets as needed (that's an entire separate discussion that goes way beyond this post).

And hey, don't fret asking multiple questions. Keep 'em coming until you've got her all figure out! That's what this forum is all about.
Click to expand...

that is great advice
 
Old Geezer said:
Slacken up that Freakin' throttle cable to be sure you have plenty of slack. No, it's not possible to put the slide in backwards with a Mikuni...there's a groove machined into the slide that must line up with a pin in the carb body in order to slide down all the way.

Once you're sure you have no tension on the cable, then twist the throttle on/off quickly to make sure you can hear the slide returning freely (you'll hear a definite clunk). If not, it's binding up somewhere. Then, start the bike and keep the throttle grip part way open if needed to keep it from dying, the adjust the throttle slide stop screw (clockwise to increase idle) a little at a time to get your idle stable (all that screw does is to lift the slide a small amount....that same effect as twisting the grip).

After your idle is stable, only then go back to the cable to adjust out any slack (but do leave enough to allow about 1/16 to 1/8" play up at the throttle grip).

And after all that, then ride the "F"unny thing at various stages of load and no-load, and check the plug burn and adjust jets as needed (that's an entire separate discussion that goes way beyond this post).

And hey, don't fret asking multiple questions. Keep 'em coming until you've got her all figure out! That's what this forum is all about.
Click to expand...

Wow this is awesome advice, sounds like its gonna work, thanks. I'll let you guys know.
 
I think something might be wrong, no matter how much i spin the slide stop screw it doesnt change anything
 
Thinking your slide might be worn where throttle adjustment screw lifts it. Worn so much that turning the adjustment screw won't lift the slide...!
 
justintendo said:
mikuni vm wont let the slide go in backwards...
Click to expand...
You had me doubting my memory so I went out to the shed got my old Mikuni vm carb and put the slide in BOTH ways just to check , to make sure I wasn't just gobbing off without knowing what I was talking about .
Put the slide in the correct way and it goes to the bottom and the bike behaves correctly .
Put the slide in backwards and it does not go to the bottom , the cable has a heap of slack , the slide idle screw does not work and the engine can rev it's ring off.

Just to make it worse there are right and left hand vm carbs and it's possible to fit the wrong slide [ rh slide in a lh carb and lh slide in a rh carb which will also give some weird problems.]
Fitting the wrong slide puts the cutaway to the engine in this instance as well .
Buy a new carb and fit an old slide is a quick way to find out about this .
 
Perhaps we're not on the same page regarding the slide location. Time for a pictorial, showing the locating pin and adjusting screw in the carb body, and the corrrect/incorrect slide installation. If you get that slide turned 180 degrees and the groove doesn't line up with the locating pin (thus not allowing the slide to drop all the way down) I doubt the bike would even start....and if it did, it would race to the moon!

SEE LOCATING PIN, DIRECTLY OPPOSITE THE ADJUSTING SCREW POST
vm body pins.jpg

PROPERLY INSTALLED SLIDE, SITTING FULLY DOWN IN THE BODY
vm correct 2.jpg

INCORRECTLY INSTALLED SLIDE. PIN IN BODY NOT LINED UP WITH GROOVE IN SLIDE, PREVENTS SLIDE FROM DROPPING FULLY
vm wrong 2.jpg

IDLE ADJUSTMENT SCREW RIDES IN THIS GROOVE (OPPOSITE SIDE, YOU CAN BARELY SEE THE EDGE OF THE MACHINED GROVE WHICH MUST LINE UP WITH THE PIN IN THE CARB BODY.
vm slide adjust.jpg

I ran out of room for pictures (can only download 4 per message). Yes, it is possible to put the slide in upside down...that would really screw things up, huh? But it can't be put in turned 180 degrees (edit: Can't be put in FULLY INSERTED) because the pin and groove won't line up and the slide will ride too high as Dukkman alluded to)....unless the pin in the body is worn down to nothing, but I've never seen that in over 45 years of riding with VM Mikunis.

Pictures tell a thousand words, hope this helps!
 
I'll be working on it again today didnt have time yesterday. Mine is like how geezer shows. Its in right i made sure when installing it.

If this helps: The bike drives, of course i dont drive it because its not running right, but i have driven it 1-3 and it has power etc etc. We tuned the bog out, but it still doesnt want to idle. I'll pull that idle screw today.
 
when you pull the idle screw take a picture of it and include the spring, I have seen people loose the spring and use something from a hardware store and if it has the wrong coils won't allow the screw to go far enough to engage the slot in the slide
 
The end is shaped how its supposed to be idk if you can tell the pic quality sucks
T8AiUDv.jpg
 
There is one other thing that can happen.
If you put the slide in with the needle fitted and the needle does not go into the needle jet but slips into the groove around the outside of the needle jet hole then the slide sticks until the plate inside the slide lifts up and the needle bends .
The slide can now almost close.
The engine will not idle properly , the throttle cable has more slack than normal and the slide can stick when you open the throttle which makes the engine rev it's ring out.

I have put the slide in a vespa backwards when I was very young and never did it again.
All the things I have mentioned I have seen in the last 3 months and I was telling a retired bike shop owner about this post and not being able to fit a slide backwards and he laughed.
Apparently it's more common than you would expect.
 
cOrPsE said:
The end is shaped how its supposed to be idk if you can tell the pic quality sucks
T8AiUDv.jpg
Click to expand...

That spring may be too heavy and coil binding not allowing the screw to actually contact the slide. You can test this by installing the idke screw without the spring. If you then have idle adjustment you need a shorter or even lighter spring . That spring looks too heavy for the application
 
You must log in or register to reply here.
Back
Top