89 Vmax tries to start be won't

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I'll do the voltage ck today.

as for the sync, I sync'd them up last year when it was running and when I rebuilt the carbs I didn't turn those screws. But as it is now it won't run long enough to look a vacuum. Maybe I should take a short video so you guys can see what is going on.

It will have changed a little bit but not enough to where it won't run, doesn't sound like sync is the problem.
 
thanks for the input Danny.
the input so far says monitor battery voltage during start and ohm out the pickup coils, both will done done in a couple hrs. I also hope to up load a short video.
 
what is the job of the pickup coil? Is it for the charging system or spark?
For spark. Your model year max has one pickup coil, earlier model years have two. It works in conjunction with magnets on the flywheel to send signals to the igniter unit, initiating the firing sequence of the coils/plugs (that was "winging it", off the top of my head, maybe an electrician could explain better)
On 1993 - on models, disconnect the pickup coil connector (located behind the left side cover, two-pin connector, black and orange wires), and measure the resistance between the wires, on the pickup coil (lower) side of the connector.
At ambient temperature,(68f.) the resistance should be 80.8-121.2 ohms.
Checking history on this forum indicates that several members have had the pickup coils fail the resistance test after the bike has come up to running temperature, but this shouldn't be the case with your bike, if it won't start.
Hope this helps. Cheers!
 
Hum, the 95 model (my parts bike) has the single pickup coil and therefore a 2 pin connector. The 89 has a 6 pin connector but only 5 pins used so I am guessing it has 2 pickup coils.
I looked on a parts list for an 89 model rotor and it called out a part number 1FK 81450-10 00.
The 95 calls out 3UF 81450-10 00... so maybe the rotor assy aren't interchangeable ??? could that possibly be the problem ?
 
Hum, the 95 model (my parts bike) has the single pickup coil and therefore a 2 pin connector. The 89 has a 6 pin connector but only 5 pins used so I am guessing it has 2 pickup coils.
I looked on a parts list for an 89 model rotor and it called out a part number 1FK 81450-10 00.
The 95 calls out 3UF 81450-10 00... so maybe the rotor assy aren't interchangeable ??? could that possibly be the problem ?


Oh yeah! The pickup signal and the ignitor have to "talk" the same langauge - they must be compatible.
The ignitor was also upgraded when the pickup coils went to the single mode style.
IMHO - flywheel, pickup coil, and ignitor must be matched.
Lets have some more opinions!
Cheers!
 
That would absolutely be the problem.. The flywheel will not work. You have to have the proper flywheel to match the pickup coils on the bike.
 
Hum, the 95 model (my parts bike) has the single pickup coil and therefore a 2 pin connector. The 89 has a 6 pin connector but only 5 pins used so I am guessing it has 2 pickup coils.
I looked on a parts list for an 89 model rotor and it called out a part number 1FK 81450-10 00.
The 95 calls out 3UF 81450-10 00... so maybe the rotor assy aren't interchangeable ??? could that possibly be the problem ?

Here is a list of changes

modest flywheel change 1990. The 85-89 VMax's and Ventures are interchangeable. The 90-07 VMax flywheels are interchangeable and some years venture (though the year they started escapes me). The Venture flywheels are heavier, have more magnet surface, and will run smoother but slow down engine response.
 
Well, that answers that.... time to get on ebay and see what I can find. unless someone out there has a rotor/flywheel which will work for an 89 vmax?

Thanks for the help guys!
 
1990+ is the 'new' single pickup sensor & flywheel. Yes, they must be from the same era, 'old' or 'new'. Wire harness will need to be changed if you want to go from the old to the new design too, along w/some of the plug-ins.
 
not sure it's worth trying to replace the entire wiring harness to solve this problem. I'll just get the correct flywheel and slap her on...
 
got the new/old flywheel installed and we have a runner, started right up. I went to sync carbs, got all adjusted to the master carb, connected the sync tool to all 4 carbs and when I started her up I gave it a bit of gas. Now sync tool has that blue liquid all over their internal tubes and can't get it to retreat back to their reservoirs. Not sure if this makes any sense. Not an expert at verbal expression.
 
Sounds like you might have forgotten the air correctors on the sync tool. No biggie. Just order a Morgan carbtune or the diligence tool from the guy on here (I think there's a banner ad now). Those motion pro sync tools are notorious for being sort of sucky.

Glad it's running anyway.
 
Glad that it is running. I used to have the motion pro sync tool. First time that I used it...I sucked up fluid from one of the tubes....into one of the carbs. Didnt hurt anything because it is blue water, but then I bought the morgan....so much better.

You can rebuild the motion pro. If I remember right, there are adjustment screws to even out the liquid in the tubes on the back of the device. Do you have a copy of the instructions?

https://www.motionpro.com/images/documents/syncpro_tech.pdf

https://9007c0109a70412e8f84-17cbb5...rackcdn.com/articles/2575_I08-0415__rev6_.pdf
 
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