Strange slight miss

[donebysunday]

I've been checking carbs on my 79, Horse, that was running well but a bit rich last year.
Had it spit from the carbs on the first 2 sets I tried so went back to the original 79 carbs that I found the PO had raised the main needles and I returned them to middle stock position. Same spit only less, spit/hickup from 2000-3500 rpm., this tells me carbs but I think I'm wrong. I feel it's coils, pickups/wires/caps. It idles great, it takes off under FWO very scary fast pulls real hard. Driving through a parking lot not good, keeps jerking. Thought I'd post after spending much time and maybe prevent going off in the wrong direction. Things I've changed, one size smaller shim on #1 & #4 exhaust valve and UNI pods to make carb swaps easier.
Thanks Guys ! Done

[motoman]

I've been checking carbs on my 79, Horse, that was running well but a bit rich last year.
Had it spit from the carbs on the first 2 sets I tried so went back to the original 79 carbs that I found the PO had raised the main needles and I returned them to middle stock position. Same spit only less, spit/hickup from 2000-3500 rpm., this tells me carbs but I think I'm wrong. I feel it's coils, pickups/wires/caps. It idles great, it takes off under FWO very scary fast pulls real hard. Driving through a parking lot not good, keeps jerking. Thought I'd post after spending much time and maybe prevent going off in the wrong direction. Things I've changed, one size smaller shim on #1 & #4 exhaust valve and UNI pods to make carb swaps easier.
Thanks Guys ! Done

Ignition, either primary or secondary is normally the root of issues, not fueling. I'd pull that left side ignition cover and tug right smartly every inch of those PU coil wires. Stretchy insulation=broken wire. At same time, unhook the vacuum advance rod from vacuum advance assembly and make sure the advance assembly rotates freely....as in floppy loose.
Could be other ignition issues added in, but this being the notorious symptom/issue would be a good place to start.

[DiverRay]

Also, look at the advance unit! I've seen a LOT of them with rust, and they do not operate smoothly. When they stick, the bike jerks and studders.

[donebysunday]

fixed but not cured

the blue wire on the upper pickup coil was broken inside, Ah HA but putting in a spice changed nothing. Come on it was broken fixing it should have changed something.


I did check the advance and it was very easy to move but when I started the bike no movement rev to 7K no movement.
Maybe a combination of things are broken ?
Thanks guys ! Done

[rdmcguy]

The miss

I had a similar thing a while back....no advance...
Discovered clogged passage on carb body...end of problem ..

[donebysunday]

Double check

ed the wires and my splice, seem OK.
Stuck a soft wire into carb nipple for the advance then sprayed brake cleaner into it, no change. Checked vacuum at the vacuum advance, seemed a bit light. Checked the hose and thought I found a hole near the nipple. Nipped off about 1/4" but no hole, had one heck of a time getting the new cut to slip over the carb nipple so maybe there was a little leakage at the nipple between it & the hose ?
Started up and now the advance works (seems a bit sluggish though ?)
Now the miss/spit is between 2K & 2.5. Before 2K it seems a bit strange, hard to explain, just not clean ? At 2.5K it kicks in and goes like crazy.
I'm thinking back to coils/wires/caps ? Then carbs again ?
It's getting better, if I was not crazy I'd be tempted to just run it but after a short run it seems a bit hot, I'm talking just in the hood doing 25-35 MPH.
Thanks Ya'll ! Done

[donebysunday]

My advance

does not work this easily.
https://www.youtube.com/watch?v=-CgQ3Uf_7WU

[DiverRay]

IT SHOULD! If you pull it out, and inspect it, you will find rust, crud, etc. on the advance mechanism itself. It will pull out so you can clean it well, then lube it up and replace it. I use synthetic grease smeared very lightly on all the rotating points for lube.

[motoman]

IT SHOULD! If you pull it out, and inspect it, you will find rust, crud, etc. on the advance mechanism itself. It will pull out so you can clean it well, then lube it up and replace it. I use synthetic grease smeared very lightly on all the rotating points for lube.

+1!..................also, I STILL suspect PU coil wire(s). No offense, but that IS an iffy connection with that big ole' butt connector. On the other hand, NOT soldering WAS a good choice.
Using a dremal, and cutting the butt connector really short, just for each wire to go into, allows for more freely movement of wires AND advance plate.

[LoHo]

Get her running and check for a vacuum leak with starter spray. You might be surprised...I was.

[donebysunday]

Octi

is strange ? LO HO I sprayed some starting fluid on all the carbs, no difference. Then I tried carb cleaner and no difference at first, while spraying suddenly a drop in RPM ? Tried again 3 Xs nothing ? Then spraying around again RPM drops, took 3 more tries to see it was the the spray on the octi that was causing the RPM drop. Pulled the vac. hose to the octi capped off the nipple, turned to prime and started the advance is now nearly right, no more spitting. So I replaced the vac. line with new and the advance works but not as fast as I think it should at least not like the video.
Just for the heck I tried spraying carb cleaner on the octi again and if enough was sprayed it killed the engine ? ? ?

Ray are there ant tips for pulling and lubing the advance ?

Motoman, I made a little tiny crimp conector to replace that one I put in.

Thanks Guys ! Done

[IanDMacDonald]

Yes. There is a great thread on cleaning and lubing the advance and pod.

[donebysunday]

Yes. There is a great thread on cleaning and lubing the advance and pod.

Could someone push my nose into this advance clean and lube thread, been searching can't seem to find it ?

[donebysunday]

Ok

of coarse in the process of removing the gigantic butt splice I put in, I lost some wire, tried to use some speaker wire that I had that seemed flexible. Not flexible enough, bends right where it should not. Been checking around town, used 1/2 tank of gas only to eventually be pointed towards an RC (remote control) race car store. Ordered some silicone 18 ga. but seems to thick and a bit stiffer than factory. Now looking at online sellers and 20 ga. so as to slice in about 2" to cover the area from the pickup that bends the most.

[IanDMacDonald]

There yah go Don: http://www.xs11.com/forum/showthread...hlight=advance

There is a great thread within the past month concerning high temp appliance wire being used for your pickup coil wires as-well.