- Posts: 4216
- Thank you received: 2414
VM26SS sync questions
- Wookie58
- Offline
- Moderator
Please Log in or Create an account to join the conversation.
- Mikaw
- Offline
- Sustaining Member
- Posts: 5007
- Thank you received: 1918
Be carful here, switch on to test yes, but should limit the “on” to a couple minutes per test. Leaving the coils powered up for more than a few minutes without them firing (discharging) can cause them to fail.remember to do your voltage checks with everything connected (back pin) and the system switched on
Primary coil connection is the battery positive connection. Yellow/red wire directly from the “off-run-off” of the right hand control. The coil secondary is black for 1-4, and green for 2-3. As Wookie mentioned ignition on, “off-run-off” to run. Black meter probe on battery ground post and red to yellow/red of 1-4, then move red to yellow/red of coil 2-3. Voltage needs to as close to battery voltage as possible. Test battery voltage on the lead block not the screws or wires. If you’re less than 1.5 below than battery you have resistance in the old harness, corrosion in the connectors, or switch contact point. Resting battery voltage needs to be 12.6. It wouldn’t hurt to test coil primary while cranking the engine when cold. Again low voltage will cause your hard start and sooty plugs til the dynamo increases the voltage. Which should be about 14.6-7 at around 2500 rpm.
You also need to test coils resistance. And the HT (plug) wires.
EDIT, Reading what is in the red square has a mistake, verified from other FSM’s. The Brown wire mentioned in the last sentence needs to yellow/red.
1976 KZ 900 A4 kzrider.com/forum/11-projects/613548-1976-kz-900-a4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
1980 KZ 750 E1
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
Please Log in or Create an account to join the conversation.
- motomisfit
- Topic Author
- Offline
- User
- Posts: 122
- Thank you received: 49
Did I mention this bike is very, very fast? Well, for a ‘76 bike anyway. It sure is a head turner. Love it
Please Log in or Create an account to join the conversation.
- motomisfit
- Topic Author
- Offline
- User
- Posts: 122
- Thank you received: 49
Please Log in or Create an account to join the conversation.
- Mikaw
- Offline
- Sustaining Member
- Posts: 5007
- Thank you received: 1918
Getting back to this what did you do with your rebuild. Your first post died with a mix up of number and measurements. Did I miss the rebuild comments.Getting better every day and I have to think that there is a bit of breaking in to do with new valves and rings.
1976 KZ 900 A4 kzrider.com/forum/11-projects/613548-1976-kz-900-a4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
1980 KZ 750 E1
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
Please Log in or Create an account to join the conversation.
- motomisfit
- Topic Author
- Offline
- User
- Posts: 122
- Thank you received: 49
Here's a pic I took while syncing my VM 28 carbs on my 76 LTD, high miles bike with freshly rebuilt carbs.
I bought a kit just like this. It had these little adjuster screws in the bottom of each gauge. I’m going along doing the syncing and all of a sudden one of the gauges started going crazy. The adjuster screw came out and got sucked INTO the hose! Holy crap! I’m freakin out but luckily the screw was too big to get sucked into the carb holder port. Whew. Lesson learned, take these screws out before you hook up.
Actually, this kit from Amazon is garbage and it’s going back. One of the gauges is stuck on 5. I ended up just using a single vac gauge I’ve had forever. Made in USA…..yeah, it matters.
I think I’m pretty dialed in on the syncing. Those are some fine adjustments for sure to get them all even. Will double check them all tomorrow, put it back together and go for a ride. Thanks again for all the help
Please Log in or Create an account to join the conversation.
- TexasKZ
- Offline
- Platinum Member
- Posts: 7593
- Thank you received: 2245
www.ocdmachine.com/carbtune-pro-4-column.html
1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough
Please Log in or Create an account to join the conversation.
- Nessism
- Offline
- Sustaining Member
- Posts: 7550
- Thank you received: 2864
I have a Carbtune and like it. Before that, I had a container of mercury, and some glass tubes. That worked fine, but despite care, the mercury would occasionally spill.A good synchronizing tool is a must-have. I have read that mercury sticks are available again (outside Kalifornia). Some guys swear they are best. I use a Morgan Carbtune and am well pleased with it. A good set of vacuum gauges are great, but hard to find and surprisingly expensive.
www.ocdmachine.com/carbtune-pro-4-column.html
Please Log in or Create an account to join the conversation.
- Mikaw
- Offline
- Sustaining Member
- Posts: 5007
- Thank you received: 1918
EDIT, How about posting pictures of the faulty set you bought to help guide new members away from junk. Thank you
1976 KZ 900 A4 kzrider.com/forum/11-projects/613548-1976-kz-900-a4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
1980 KZ 750 E1
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
Please Log in or Create an account to join the conversation.
- motomisfit
- Topic Author
- Offline
- User
- Posts: 122
- Thank you received: 49
Please Log in or Create an account to join the conversation.
- motomisfit
- Topic Author
- Offline
- User
- Posts: 122
- Thank you received: 49
It was a pain doing it this way, but I am now even on all 4 carbs. It was 90 degrees here in the desert all weekend, so I had to let the engine cool off several times. They ended up at 9 inches vacuum, fwiw. I was only able to take it for a short ride up and down the block and it’s running pretty darn smooth. Will go for a long ride later today and post final thoughts and pics of the bike. Will also post what I did in my rebuild and why.
Please Log in or Create an account to join the conversation.
- motomisfit
- Topic Author
- Offline
- User
- Posts: 122
- Thank you received: 49
A good long ride today. Ran great but still a little pop out of the #1 carb every so often. Syncing the carbs, although I’m glad I did it, didn’t seen to make a whole lot difference. Spark plugs are still blacker than they should be. I have now the Dyna S ignition kit and it will be my next upgrade. I haven’t checked my voltages at the coils yet but battery voltage static is fine. It starts now cold with full choke instantly so that’s a good thing. I honestly don’t know why it was taking so long before but as I said in a previous post, it might have been the fuel. I’ll post again when I get the Dyna system in.
Please Log in or Create an account to join the conversation.