Carburetor idle circuit cleaning

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We see this all the time.The mechanics do not know the vmax.They do not see them very much or if at all.
You need to run some seafoam through it and then probably do the shot gun or peashooter to clean it out.
 
Marky_max said:
I am new to the forum and have a similar rough running problem.
Funny thing is the bike just came back from a big service that cost me 500bucks. But that is another issue.

I think I want to also check my fuel filter.
Can anyone tell me where to look to find it?

Under the seat. Take off the four bolts holding it on (flip the middle forward and there will be two screws clearly visible in the sides and the last two run through the pivot area - don't worry the springs won't go flying all over). Then you can leave them out as the seat isn't going anywhere once it is clicked into place.

Sean
 
Thanks Sean and One2DMax.
I'll look for the filter. My mechanics here tell me they can get one in for about 10 bucks.
Anyways, I have run the nearest equivalent to seafoam that I could find through the system.
First day after putting it in it actually exacebated the problem. I mean serious backfiring coughing and sputtering.
But as soon as it got hot and run around a bit it was perfect.

I thought I would test it this morning so I went out early. Started perfectly, no hesitation rode it gently while it warmed up, no backfires, no stuttering, no hesitation. When it was hot it was the same. So like the issue has completely disappeared. It seems the seafoam, or in my case the nearest equivalent I could find, is just the ticket. :eusa_dance:

Now just one other little annoying thing. My bike has been tight and clean since I bought it, even though it has now done 23000 miles. But in the last couple of days I have seen a little oil, not much, about the size of a quarter, spot under it. So maybe the mechanics didn't get a perfect seal on the oil filter gasket.. very annoying...:damn angry:
 
Well I have got my bike working perfectly again.
After I poured a few tanks of system cleaner through it beleive it or not it was actually getting worse.

Then I remembered. I put a T-boost kit on it and at the same time an ITAM (Integrated Timing advance Module). Anyways, I checked that, (this meant I had to take one of the faux scoops off) and it was set at 3 degrees advanced, which is where I had put it based on trial and error when I fitted the T-Boost. So I thought, lets play with that.

There are 3 settings, 0 degrees advanced, 3 degrees advanced and 5 degrees advanced. I thought it would be best to try it at 0 degrees advance just to be safe and voila. Like I have a new bike. Starts great with choke, idles at like 6-700 rpm with choke off straight after that (well that is what the gauge says) and runs smooth right through the rev range. Still pops a bit on decel but nothing like before and it is smooth as butter on accelleration..

I think I did notice that it is just a tad less exciting on the wind up into the higher revs and if I were racing it in hot weather with the engine warm I think I might go back to the 3 degrees advance but it is running perfectly for burning around town and just playing with the sports cars at the lights and stuff...

Oh and the oil spots seem to be going away, maybe they just didn't clean the bike underneath. Well they said the thread on the drain plug was worn so I have a new plug on order. I am also getting a new fuel filter. I guess I don't need it now but then again it can't hurt and it is not really expensive, about 15 bucks I think he said...

Big smile is back on the face...
 
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Where did you find an ITAM?I have never heard of one on a vmax.I just bought a dyna 3000 ignitor for mine that is adjustable.Mostly for the 2 stage rev limiter.I personally do not like tboost either!I had one for a week and then removed it.To me it felt slower than stock.

Did you disconnect the stock ignition advance to hook up this ITAM thing?
 
Marky, about that oil leak. I found that when you change the oil and torque it at the rec. spec. 14ftpds. It will leak a drip or two for a day or two. For some dumb reason it takes a bit for the ring to seal. I torque at 18 now.
 
Ibrahim, if you blow through the mixture screw hold air will blow out from PAJ1 at the top of each carb and also PAJ2 behind the slide diaphragm. I would remove the slides, mixtures screws and get carb cleaner in each oriface. That includes the main air bleed, 3 holes for the purge jets, mixture screw hole, and both PAJs.

Something else you can try is a fuel additive called Seafoam. You can get it at O'Reilly's or any other auto store. It comes in a which can with red lettering. I put a 3rd of a bottle in the tank and it'll clean your entire fuel system including the carbs and combustion chamber. Idle seems a bit more crisp.

Take care,

Mark,I'll second that seafoam cleans them out real good.carbs,valves,I even use it for stabilizer over the winter.I run about a 1/3 bottle through mine every 3-4 tanks.The quality of the gasoline nowadays is very questionable anymore.Summer is coming,corngas is on the way.Techron is supposed to do well too. Shawn

SeaFoam is a great product and so is Techron additive. If you can't find the seafoam the Techron works just as well.

Sean

I'll fourth this one and I know my buddy (4warnd) will 5th it... It works wonders... :drool:

They also make a bug remover that you spray on before wetting the vehicle then let sit for 30 seconds and wipe with a wet rag and they come off clean without scrubbing...:surprise: AWESOME!

I have shot the shootgun and it works but it is time consuming. Remember to cover the top of the carbs when spraying the carb cleaner in the idle screw holes because it comes spraying right out the top and lands on the bike. Carb cleaner and paint don't mix...:whistlin:
 
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That sea Foam works great! I put about 1/3 of a can in a 1/2 tank of gas and now she's running alot smoother:punk:
 
I did the shotgun today on my 06 max, after winter storage vmax was running very poorly due to the right rear carb backfiring, all other carbs seemed fine (discovered this while syncing carbs) I tried sea foam, but the one carb would not clean up, backfiring and running very bad at low rpm operation but seemed fine after 2800 rpm. i did shotgun to just the one carb (even bought an air compressor for the job=150.00 instead of 350.00 the dealer wanted to take out and clean all carbs!) This bike had only 4200 miles and i stored it properly for winter but needed this shotgun procedure because now vmax is running like new again!:rocket bike:
 
Seafoam is also an excellant fuel stabilizer for winter.Read the can.I put it in all my tanks everyfall.Might even clean some tuff shit out sitting for 3 or 4 months.
 
My bike, 1998 Vmax was running ragged off and on since I got it. I ran seafoam through it, several tankfuls, very heavy, over 1/2 can to 3/4 of a tank. I screwed with carbs enough I had to take it in for a resync. After that, the bike ran great for about 3 days, then started missing under heavy load again (full throttle 1st thru 3rd). Actually thought it was electrical but before going that route thought I would try the shotgun. It worked fantastic and the bike now runs great. I had to replace an idle screw, previous owner(s) had messed one up pretty badly. The dealer actually had 1 in stock :surprise:.

Thanks to all the guys and the knowledge they offer on this forum. Without you folks us newbies would be at the mercy of the dealer, and I think it is understated that they (in most cases) don't know crap about these bikes.

If your bike is running ragged, try the shotgun before you even think about going to a dealer. The first post in this thread has a great link on how to do this.
 
John, glad your bike is running tip-top!

Thanks, it is sure nice to be able to get on it and have everything working properly. I love this bike and have since I had read about them and from the day I laid eyes on one back in 1985. No other bike looks like it or runs like it.
 
I am at my wits end! :bang head: I have an 03 with 4000 miles. It will run only with the choke on. I have cleaned the carbs 3 times ie. blowing out the idle circuit, checked fuel pump operation, vacuum leaks etc. I always stored it with Stabil.
Diaphragms are good.

I can start it with full choke, but as soon as I start backing of the choke it dies. If I really rev it I can kinda keep it running but as soon as I let off it dies.

My latest theory is plugs. I was only able to get champion plugs and figured they would be ok to get it running. Could this be an issue?

Any advice would be greatly appreciated.
 
How does your fuel filter look?

Drain your float bowls to see how fuel looks and see if bits of dirt come out. Check your float level too.

I have never used Champion but heard of issues with them. You can get NGK plugs at Advance, Pep Boys, O'Reilly's, etc.

If it still runs like crap, time to split the carb rack and disassemble and clean your jet block.
 
I woke up one morning and my Vmax ran like crap. It ran perfect the day before. Had to keep the choke on to keep it running. Got on this webpage and read about the Shotgun. Did it and now the bike runs great again. A month later the bike still runs good.

BTW. I went ahead and pulled the #1 and #2 air jets even though it didn't look like I really needed to. I drilled out the idle jet plugs. The jets are actually quite a ways up in there, so not too close behind the plug. I set the idle jets about a 1/4 turn richer. Seems to have a smoother transition, but could be just because it's cleaned up inside now.

Just one more vote for the Shotgun.

thanks to whomever posted this procedure.

Smackdown
 

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