Surging

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gtotiger1

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My 88 max all the sudden started surging between 2000 and 3200 rpms, when cruising, can this be a clogged pilot? I tried the shot gun with no difference, changed the plugs also, is there a way to clean the pilot jets without breaking down the carbs? Also tried alot of seafoam, no difference !
 
Just to say, it's caused by a too lean condition.. Running Untreated Ethanol???? Trash may have worked into the carbs. Try draining the carbs into a Paper Cup or Glass Jar to see if fine particles are in the carbs. Screw is loosened on the right side of each carb and the drain hose is the one that sticks out under each carb.
 
I have recently started using startron enzym to treat my fuel, seems to make no difference, any other suggestions guys?
 
My 88 max all the sudden started surging between 2000 and 3200 rpms, when cruising, can this be a clogged pilot? I tried the shot gun with no difference, changed the plugs also, is there a way to clean the pilot jets without breaking down the carbs? Also tried alot of seafoam, no difference !

Hard to say. The short answer to your question is, no, there's no way to properly clean the slow speed or pilot circuits without removing and disassembling the carburetors. But before you go disassembling the carburetors, a little more information would be helpful:

When you say all of a sudden, did anything change? For example, did you just get gas?
When you say surge, do you mean hesitation, missing, breaking-up et. al.?
Does the bike idle steadily at 1,100 RPMs?
Does it pop or backfire on deceleration?
 
I did not recently get new gas, surging to me is if held steady at 2500 rpm it wants to go more, but just surges, there is no backfiring involved, and the 1100 idle has a bit of a miss too

thanks
 
I did not recently get new gas, surging to me is if held steady at 2500 rpm it wants to go more, but just surges, there is no backfiring involved, and the 1100 idle has a bit of a miss too

thanks

It's possible that one or more of the carburetors have a slow speed circuit problem, but that wouldn't happen all of a sudden as you describe. That would be noticeable after the bike sat for awhile with untreated fuel in the carburetors.

You say it misses at normal idle. Does the idle speed surge at all? If so, it could be an air leak. That's easy enough to check. When it's idling, spray each intake manifold with carburetor or brake cleaner and see if the idle changes. If it does, that indicates an air leak.

When you're through checking for air leaks and assuming there's no problems, I'd check the carburetor synchronization. It's quick and easy to check provided you have access to vacuum gauges.

Putting the low mid-range surge aside for a moment, how does the bike accelerate from right off idle through the mid-range? Any misses. bogs, etc?
 
I use Sentry if I'm out and have no choice but Ethanol. The bikes runs the same as they do with Non Ethanol..
Without treatment, it's hard to keep them running, they miss, stumble and surge.
 
The idle does not surge, its a bit loppeyer than normal it may be missing, i tried the propane trick, and found no air leaks at all, as for sync its spot on, synced it at 1500 rpms, the acceleration in the low to mid is a bit sluggish, but once it hits about 4000 rpms she pulls good
 
It sounds like you have a plugged idle circuit. Remember, the idle circuit has primary control over fuel flow until ~4k rpm when the needle take over. You can also do the peashooter as well, this requires removing the idle mixture screws. Be very careful with the idle mixture screws when removing them. It takes a small flat blade screwdriver and the screws are made of brass. If it stops turning do not force it or it will strip out on you and then you have issues.
 

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