Carb Sync

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Kenreesesr

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Looking for a really good tutorial on how to sync the carbs. Has anyone made a video on the subject for the Vmax?
 
There's one on YouTube, but doesn't show him adjusting the screws. If you have the Morgan, it's real simple.
 
There are some u-tube clips on this, plus the manual isn't too bad with sync info.
You can get a free on line manual here http://www.vmaxoutlaw.com/main.html It's in the vmax tech and info section.
And, great to have. I'd bet there is a lot more info on this forum too. Usually a thread search can lead to helpfull infomation
on almost anything Vmax related.
 
Last edited:
Looking for a really good tutorial on how to sync the carbs. Has anyone made a video on the subject for the Vmax?

Kenreesesr, attached is a PDF quick reference guide I use; compiled from VMF site info. :worthy:

Hope it helps.
 

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  • Carb sync procedure sept11.pdf
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If you use a homemade sync,use restrictors.I tried with and without & found it easier with them.less fluid bounce plus if carbs are way off,it will buy you more time before your max drinks it.
 
There's a sticky post in the carbs section.

http://www.vmaxforum.net/showthread.php?t=3959

Thanks for all the responses. Joining this forum has been incredible. Almost as good as the Vmax itself. I've gained much knowledge from this forum. I hope I can return the favor. I'm currently working with Pit Bull on a set of stands for the 1st Gen Vmax. The custom rear stand is on its way to me, and I'm sending the required dimensions for the rear stand to Pit Bull. They have been great to work with. I'll post pictures once I receive both stands.
 
Tip: Small changes on the screw will have great impact on your readings....actually, just putting pressure on the screw will change it some. So make small changes and always blip the throttle after each change.

Practice is a big thing with sync, the more you get the better you'll be at it.
 
If you use a homemade sync,use restrictors.I tried with and without & found it easier with them.less fluid bounce plus if carbs are way off,it will buy you more time before your max drinks it.
The closer the restrictors are to the manifolds, the less the flutter.
Steve
 
Thanks for all the responses. Joining this forum has been incredible. Almost as good as the Vmax itself. I've gained much knowledge from this forum. I hope I can return the favor. I'm currently working with Pit Bull on a set of stands for the 1st Gen Vmax. The custom rear stand is on its way to me, and I'm sending the required dimensions for the rear stand to Pit Bull. They have been great to work with. I'll post pictures once I receive both stands.


Who needs a stand for the Vmax? Even if your centerstand tabs were cut off for an exhaust a run of the mill ATV lift (two pad lift) works perfectly and lifts both wheels off the ground. You can get them at Harbor Freight for like $50 if you catch them on sale.


Anyway in a nutshell....

1. Remove the two "H" covers off the manifolds. Two philips screws on each.
2. Remove the three rubber covers from the nipples. The left/front one has a line that runs to the vacuum advance (boost sensor). Just pull it off.
3. Hook up your carb sync tool to the four nipples.
4. Start the engine and let it warm up until you have a steady 1000RPM idle.
5. Adjust the flathead screw on the left side of the bike, between the two carbs, until carbs 1/2 are balanced in vacuum to each other. Blip the throttle after each adjustment. Make small movements, like 1/8 turn at a time.
6. Adjust the rear screw on the right side until 3/4 are matched, or nearly so.
7. Once 1/2 and 3/4 pairs are in tune, use the front right screw to balance the left pair to the right pair. Again, blip the throttle after each adjustment.
8. Remove gauge lines, reinstall covers/sensor line, and reinstall the H covers.

Once you've done it once or twice it takes around 10 minutes start to finish, and 5 of that is warming up the engine.

The best I could ever do was get all four within 1 inHg of each other, and for me they all hovered between 6 and 7 inHg vacuum at idle.
 
Who needs a stand for the Vmax? Even if your centerstand tabs were cut off for an exhaust a run of the mill ATV lift (two pad lift) works perfectly and lifts both wheels off the ground. You can get them at Harbor Freight for like $50 if you catch them on sale.


Anyway in a nutshell....

1. Remove the two "H" covers off the manifolds. Two philips screws on each.
2. Remove the three rubber covers from the nipples. The left/front one has a line that runs to the vacuum advance (boost sensor). Just pull it off.
3. Hook up your carb sync tool to the four nipples.
4. Start the engine and let it warm up until you have a steady 1000RPM idle.
5. Adjust the flathead screw on the left side of the bike, between the two carbs, until carbs 1/2 are balanced in vacuum to each other. Blip the throttle after each adjustment. Make small movements, like 1/8 turn at a time.
6. Adjust the rear screw on the right side until 3/4 are matched, or nearly so.
7. Once 1/2 and 3/4 pairs are in tune, use the front right screw to balance the left pair to the right pair. Again, blip the throttle after each adjustment.
8. Remove gauge lines, reinstall covers/sensor line, and reinstall the H covers.

Once you've done it once or twice it takes around 10 minutes start to finish, and 5 of that is warming up the engine.

The best I could ever do was get all four within 1 inHg of each other, and for me they all hovered between 6 and 7 inHg vacuum at idle.


I'm confused... What supports the weight of the bike with your harbor freight lift?? The exhaust on a vmax hangs below the frame.
 
Yes, the stock pipes are strong-enough to support the bike if the jack is positioned properly.
 
I just built a wooden frame that lifted via the frame rails and not the head pipes. Have two so can lift two different bikes without touching anything but the frame. Only problem is getting the wooded frame under the bike, especially if the bike is lowered any.
 

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