Performance Issue

[Fastatv]

What's up guys? Hey, I've been fighting an "off idle " now for a month or so....finally about to give up and ask for some knowledge here. Details/info:
- After the engine completely warms up, most of the time it's difficulty to start, requires a little throttle
- After warm up, sometimes has a bit of a hesitation from 1000 to about 1600 or so rpms...almost a "spit" if I may as this isn't easy to describe

What I have tried:
1) Synced carbs
2) Adjusted air/fuel from 2.25 to 3.25 turns fron seat...worse at 3.25 ( rich )
3) New K&N air filter
4) By now, probably 2 cans of Sea Foam
5) New plugs gapped at .032

Runs absolutely great everywhere else. The PO told me that the Max does not run well under 3,000 rpms but that doesn't fit with me...any engine should be capable of being dialed in at any RPM.
Anyway, this only happens when the engine is really warmed up....after normal running at 60 to 70 mph. In regards to the temp indicator, at full warm up, the temp needle is about 1/32" or so under the black dot ( apparently the center of the gauge ). Is this where it should be? I ask because to me, this seems to be somewhat of a heat related issue. Thanks for any help on this. Rick

 

[tugla]

have you tried doing the pea shooter and shot gun cleaning methods for the carbs. will help clean up the idle circuit.

 

[firefly]

Try the pea shooter first, its easier to do, use an eye dropper with seafoam and follow the procedure, scroll down the page.

http://home.comcast.net/~onlyone12/carbs1.htm

 

[acammer]

I have this issue too, I end up (what I think is) very rich at full hot idle, and I have that off idle stumble when blipping the throttle. Or, if I roll on too much throttle under 2000rpm I'll get a pretty abrupt stumbling as well. 2500rpm on up, I can slam it wide open without the slightly issue, and pulls hard and clean to the rev limiter. I settled it down some with a/f adjustments, but I can't seem to get it dialed out, partly because my two right side screws are fouled up - thank you prior owner. When I tear into the carbs for a rejet, I will probably drill and remove those stuck screws so I can get it 100%. But, for the most part, I just live with it - it doesn't stall, and it doesn't hurt performance in other than a very narrow window of operation, and only if I push it to that point.

 

[VMAX1260]

many V-max engines have the hot start problem. so i dont think this goes with your problem.
you may have synchronized your carbs ,a/f ratio plugs e.t.c but you dont know what you will find int he carbs when you open them. i think you need to open them and clean them. if your problem is in the low rpm then before opening them do one thing. remove one by one the air fuel screw and blow inside compressed air . i had the same problem once and that solved my problem in 5 minutes. if that doesnt cure it. then you must clean them in all means.

 

[CaptainKyle]

Damb I must be delirious from driving all day I saw the title of this ( performance issue) & my mind went in the gutter I was thinking some one needs to talk to there wife or doctor.:rofl_200:Soory hope I did not defend any one I just have a warped sence of humor.

 

[The Beekeeper]

+1 on the shotgun, developed runability/performance issues, performed this procedure on the carbs and it was like magic!..............not that difficult to do and doesn't take too long..........................Tom.

 

[firefly]

What's up guys? Hey, I've been fighting an "off idle " now for a month or so....finally about to give up and ask for some knowledge here. Details/info:
- After the engine completely warms up, most of the time it's difficulty to start, requires a little throttle
- After warm up, sometimes has a bit of a hesitation from 1000 to about 1600 or so rpms...almost a "spit" if I may as this isn't easy to describe

What I have tried:
1) Synced carbs
2) Adjusted air/fuel from 2.25 to 3.25 turns fron seat...worse at 3.25 ( rich )
3) New K&N air filter
4) By now, probably 2 cans of Sea Foam
5) New plugs gapped at .032

Runs absolutely great everywhere else. The PO told me that the Max does not run well under 3,000 rpms but that doesn't fit with me...any engine should be capable of being dialed in at any RPM.
Anyway, this only happens when the engine is really warmed up....after normal running at 60 to 70 mph. In regards to the temp indicator, at full warm up, the temp needle is about 1/32" or so under the black dot ( apparently the center of the gauge ). Is this where it should be? I ask because to me, this seems to be somewhat of a heat related issue. Thanks for any help on this. Rick

Check charging voltage & idle voltage across the battery terminals you should get above 12.50 at idle and 14+ at 1500RPM.
when the bike is hot does it feel like the battery is weak when trying to start?

 

[alorio1]

I would recommend the shotgun treatment, you will have to remove A/F screws so make sure you have a screwdriver that fits well into the A/F screws. I would spray a little PB Blaster in the A/F screw holes and let it soak in for a bit before I attempted to remove screws. Also make sure air box is seated on carbs and clamped tight. I always disassemble needle assy to make sure PO has the needles installed correctly in the slides and if he has shimmed needles. There is a small plastic spacer that has a point that needs to go into a hole of the slide. If this is out of place it could cause performance issues because the needle is not setting straight and is about 1/8 shorter making things richer. When reassembling needles be sure not to over tighten plastic headed screws because they will snap the head off in a blink of the eye. I always use two fingers on screwdriver when tightening these. The A/F screws have an O-ring which usually stays in the carb when screw is removed, but sometimes it will come out with the A/F screw and fall to the floor never being noticed because of their size and they make no noise when the hit the floor. I have noticed carbs do not react well to adjustments when these O-rings are missing from screw. If the O-ring is not on the screw it either stuck inside the carb housing or it was never there because someone else blew it out with compressed air. When I pull a A/F screw and the O-ring doesn't come out with it I have a stiff small wire, with a small pick like bend on the end, and fish for it so I don't make the mistake of adding another O-ring which might affect adjustments also. If the shotgun method doesn't help the you may have to do what VMAX1260 suggested.

 

[Fastatv]

Check charging voltage & idle voltage across the battery terminals you should get above 12.50 at idle and 14+ at 1500RPM.
when the bike is hot does it feel like the battery is weak when trying to start?

I'll Check this tomorrow. Just seems like a heat issue to me but I do sometimes get tunnel vision.
No, the battery doesn't seem week at all. Question: does the 95 Max have accelerator pumps? I ask this because it starts better with a little throttle. If it doesn't have pumps, this would mean more air which would confirm a rich issue. If pilots were somewhat dirty, that would indicate a lean issue....
Where does your temp gauge indicate when fully warmed up? Thanks, Rick

 

[Fastatv]

I would recommend the shotgun treatment, you will have to remove A/F screws so make sure you have a screwdriver that fits well into the A/F screws. I would spray a little PB Blaster in the A/F screw holes and let it soak in for a bit before I attempted to remove screws. Also make sure air box is seated on carbs and clamped tight. I always disassemble needle assy to make sure PO has the needles installed correctly in the slides and if he has shimmed needles. There is a small plastic spacer that has a point that needs to go into a hole of the slide. If this is out of place it could cause performance issues because the needle is not setting straight and is about 1/8 shorter making things richer. When reassembling needles be sure not to over tighten plastic headed screws because they will snap the head off in a blink of the eye. I always use two fingers on screwdriver when tightening these. The A/F screws have an O-ring which usually stays in the carb when screw is removed, but sometimes it will come out with the A/F screw and fall to the floor never being noticed because of their size and they make no noise when the hit the floor. I have noticed carbs do not react well to adjustments when these O-rings are missing from screw. If the O-ring is not on the screw it either stuck inside the carb housing or it was never there because someone else blew it out with compressed air. When I pull a A/F screw and the O-ring doesn't come out with it I have a stiff small wire, with a small pick like bend on the end, and fish for it so I don't make the mistake of adding another O-ring which might affect adjustments also. If the shotgun method doesn't help the you may have to do what VMAX1260 suggested.

I may check these tomorrow. Bedsides the "O" ring, shouldn't there also be a small flat washer that the "O" ring seats on ....screw, spring, flat washer, "O" ring?

 

[alorio1]

Yes, there is a small washer I forgot to mention.
A few more issues that could affect performance;

Leak in manifolds & carburetor boots
Carbs out of synch
Floats out of specs

 

[alorio1]

You may already have this but here it is again;

 

[Fastatv]

Check charging voltage & idle voltage across the battery terminals you should get above 12.50 at idle and 14+ at 1500RPM.
when the bike is hot does it feel like the battery is weak when trying to start?

Charging checks good. I'm going to try to adjust the a/f screws once more...per acammer's idea. If this doesn't help/resolve, I'll move to the "peashooter and/or the "shootgun" method. This problem doesn't have much affect on actual drivabilty....just sucks not be right. :bang head: Thanks

 

[davidon]

Your pilot fuel jets are clogged. gotta disassemble jet blocks pull pilots out and spray them out with cleaner..only way to resolve it

 

[Fastatv]

Charging checks good. I'm going to try to adjust the a/f screws once more...per acammer's idea. If this doesn't help/resolve, I'll move to the "peashooter and/or the "shootgun" method. This problem doesn't have much affect on actual drivabilty....just sucks not be right. :bang head: Thanks

Problems appears to be resolved. I took acammer's advise ( also read this in the "how to " area ) and adjusted each carb, one at a time after complete warm up. Took each one in till cyclinder was dead...opened the a/f until engine smoothed out, then another half turn. The "spitting" and stumbling is completely gone....starts much better when fully warmed up. There was also a slight popping in the left side exhaust ( when cold ) which is now also gone. unk:I haven't checked but I think the a/f screws vary from 2.75 to 3.25 turns out. For some reason, I thought each carb should be set exactly the same ( experience with previous bikes ). Guess I'm still learning. Thanks to all for your tips and recs. Rick