spittin carbs

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When you sync your carbs it adjusts those butterfly valves. They won't necessarily be all the same. Once you get your carbs back together you'll need a sync gage and hook the lines to the ports in the manifolds. You have to take those plastic "H" covers to see them. Using drill bits to sync carbs is what's done for Keihin flat slide carbs. Mikuni CV's...nope.

Mark
#1098
 
well got carbs synced, still runs like its on 3 cly till it gets up around 3000 rpms, more noticeable town riding, perfect after 3000 or on road. mech thinks its electrical problem now that the carbs are out of the way and im out 450 dollars on them bastards. so here is whats going on, i left spark plugs in it and took two plug wires off one side it reved up and idled pretty good two have two plug wires off, did the same to other side and it wouldent hardly rev up and would crack and pop when i held it at 3000 rpms, and it would quit on me at idle whicth the other side dident. could it be the coils? im about to the end of my sanity with the max please help. my e mail adress is [email protected] please mail me with any info on this. i have trouble finding where anyone answers my questions. thanks again
 
Remove the spark plugs and then fit in the plug boots. Now set them so the plugs sit on the valve cover or engine so they're grounded. Push the start button and make sure all four plugs are firing.

Mark
#1098
 
First off, what year is the bike, how long have you owned it and when the problem start?

Footnote: You should never have the engine firing without having the plug wires grounded. This could destroy your ignitor unit.

If you don't have a service manual, you will need one. You can find one online at the vmaxoutlaw site.

Now, if all 4 plugs have proper spark after testing them (by removing all 4 sparkplugs, leaving them plugged in the spark plug wires and grounded to the engine - turn ignition on and hit the starter botton). If they all spark, than I would check the complete carb system first. Use the step by step in the sevice manual.

Remove air box or individual filters, complete carb bank and complete manifolds vboost system. Check condition of rubber o'rings between the manifolds and engine heads. Check vboost and manifold rubber boots for cracks (can only be done by taking the manifold assembly apart and bending the boots to see for cracks. Next take the carb bank apart, then each carb completely apart (one from the bank at a time) Check all rubber o'rings including the ones from the air/fuel mixture screws. Check the rubber diaphram for cracks and remove the needle set and make sure the all the pieces are there (compare to diagram in service manual), than reinstall it and make sure it is seated properly. Use carb cleaner and compressed air to clean all passages. Reassemble the carb, set the air/fuel screws to 2.5 turns and set the float levels and put back on the carb bank and on to the next one.

Put carb bank back on and air box/filters, throttle cables, etc... Start bike, warm it up and do the carb sync and go for a ride.

Is this alot of work, YES, but if you have the mechancal ability and follow the step by step proceedure in the service manual, it should solve the problem you where having or you will know for sure that it is an electrical problem. Either way your carb system will be 100%.

Completely redoing your carb system from start to finish will save you alot of aggrevation and second guessing. Just make sure you follow all the steps in the service manual.

Good luck

Mike
 
i had the carbs cleaned twiced, same shop checked electrical system, said i needed to change my pilot jets. bike is all stock and runs great on road above 3000 rpms its the town riding is when its like its running on 3 clys when it gets to 3000 its like i hooked up the 4th plug wire. it will crack and pop if you let it sit on stand and hold throttle at a steady 3000 rpms. any help on this before i take it to a differant shop tommorow and spend another 500 dollars? 2000 stock v/max
 
Did the shop remove the pilot fuel jets from the jet block when they cleaned the carbs? I always do that....otherwise there's a good chance they'll still be plugged. If it runs great at the top end it's unlikely a problem with the ignition system.

Mark
#1098
 
I've had slides intermittently stick and cause this, hard as hell to find.

Pull the air filter and reach down in the carb throat with something small diameter like a long screwdriver and push the slide in a make sure they go in easy and come back out quickly without hanging up.

Mine ran like crap when it did this and I could have sworn it was an ignition problem.

It was caused by a misalignment on the needles making them drag and stick on the neddle jet.

Rusty
 
yes he said he did take them out. but another mechanic there said it was a lean pop. i got the bike at 7000 miles and it was doing it then. im about to give up.
 
yes the slides are free not sticking. i dont no if they checked the coil down by the stator. what would this do if its bad?
 
The ignition would cut out....similar to pulling a plug wire. When mine went bad it dropped to 3 cylinders. Others have had it drop 2 or it wouldn't fire at all. Mine's an early model so there are two p/u coils. Late models just have one.

Mark
#1098
 
i had the carbs cleaned twiced, same shop checked electrical system, said i needed to change my pilot jets. bike is all stock and runs great on road above 3000 rpms its the town riding is when its like its running on 3 clys when it gets to 3000 its like i hooked up the 4th plug wire. it will crack and pop if you let it sit on stand and hold throttle at a steady 3000 rpms. any help on this before i take it to a differant shop tommorow and spend another 500 dollars? 2000 stock v/max


I know a guy in Pittsburgh that might be willing to work on it for you.He is one of the best with these carbs if not the best.

pittsburghpaul,Where'd you go?
 
pittsburg is way to far for me. my zip is 25550. wv. my shop said the coil by stater cant be checked, besides i dont know how to get that pick up coil out with no puller. dont no where to turn. may go look at used hayabusa today. its fuel injected.
 
Yes, it can be checked. You measure where it connects to the main harness. Just follow the wires from that rubber cover on the left side. They go by the clutch bleed nipple. One of the bundles is for the stator and has 3 white wires. The other is for the pick-up coil. Resistance of the coil should be about 110 Ohms at room temp.

Mark
#1098
 
pittsburg is way to far for me. my zip is 25550. wv. my shop said the coil by stater cant be checked, besides i dont know how to get that pick up coil out with no puller. dont no where to turn. may go look at used hayabusa today. its fuel injected.

Don't give up now...

I have a fuel injected bike and yes it's nice but that by no means means it's trouble free...:whistlin:
 
Don't give up now...

I have a fuel injected bike and yes it's nice but that by no means it's trouble free...:whistlin:

+1 to that - any bike has it's weak points ans all require a certain amount of maintenance. Also, I learned a long time ago that most shops and all dealerships charge high $$$ to fix your bike and they have apprentices service the bike. I'm not saying that all apprentices are bad, but at $75.00 to $85.00/hour - no thanks, I'll do it myself.

Have a look at the VMF links - to vmaxoutlaw - there's a service manual online - after looking at the carb section, you find it easier than you think to fix yourself.

Good luck
Mike
 
i dont know where to start this time. any ideas? may check valve clearance, i have manuel but does anyone know what mm the valves should be at when cold? thanks. gonna do another spark plug check in morning. its been a real head banger. thanks. ps after getting carbs cleaned twiced in less than a year, i would like to look elsewhere for my problem. the next carb job will be done at mad max/s.
 
The manual has a chart and specifies the range in inches and millimeters. Intake and exhaust clearances are different.

Mark
#1098
 
is it very likely to be in my valve adjustment? it has 11000 miles on it and never been adjusted, when its warmed up i can hear one louder than the rest, its the one where spark plug is a dark grey the others are light grey. could this be a sign of hope? or if i ckeck my timing would that tell me my valve adjustment is ok if it showed up being in time? thanks.
 
Valves are adjusted every 26,500 miles so yours should be fine. Have you done a compression and/or leakdown test?

The timing on a Vmax is fixed but you could still check it.

Mark
#1098
 
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