First time working on multiple carbs on the Trashboat

[motoman]

Plugs looks good.........you have some sort of secondary ignition issues, pick-up coil wires, etc. The other thing is, have you checked the advance unit under that left cover to make sure it EASILY moves by hand.....as in floppy loose. If it's not, your gonna have to remove it and clean the whole advance unit of any rust. Just throwin' out ideas, and that IS a biggie to get these to run smooth under load.

[Rasputin]

Without going back and reading all the posts I have a couple of thoughts here. Not trying to bust you or anything but I think the synch and the idle position screw are off their proper spot.
Was the gas cap vent not working during the synch? Video shows the thing with the tank on backwards. If the synch was done before the vent was fixed I would suspect the synch is off.
Did you keep an even temperature while doing the synch? I notice on the video that there was no fan present, so if that was the case when synching the carbs it would have gotten increasingly hotter. This would make a decent synch next to impossible. I have even had issues with using too strong of a fan and cooling the center two cylinders more than the outer ones. Used a leaf blower without any diversion on that one.
Were the carbs preset before installation? By that I mean did you use the bread tie method or the three hole butterfly method before installing them? If so, how far was the idle position screw turned in from the stop. If it is too far off the stop position the carbs could be set to where "they think" they are halfways open.
One can set the idle and synch in this position and then it will run like crap. I personally made this mistake "no DAMHIKIJD".
Was the synch done before or after the tight throttle cable was noticed. It may have been pulling a wee bit during the synch and threw it off a little.
I think it was Nate who asked if you set the idle air with the morgan carbtune, but I think I recall you mentioning that you did it by ear, but as pilots play a bigger part than just during idle I wonder if that could be out a bit.
Are all the vents to the carb free and clear?
Did you take the carb bodies off the rail when you cleaned them?
Is your choke linkage still in place with all it various springs and balls etc and were they cleaned as well?
Did you spray around the carb system with water or propane or anything else to detect leaks or just order new carb boots and install them?
Is your timing spot on?
Have you checked the valve shims and compression etc?
Like I say, just a couple of thoughts and questions that I ask in case you missed something or it jogs another members memory. Every once in a while a "Dumb" question (like mine) asked by another member will get the whole groups thought processes flowing. Good luck!

[sparkfly88]

Found myself some bad pickup wires!

[motoman]

Found myself some bad pickup wires!

Well, if that outer sheaving stretches, you've found the culprit! For the fix, would NOT solder. Take a naked butt connector, shorten it with a dremal cut-off wheel or equivalent, slip a short piece of shrink tubing over one wire, crimp each wire into the shrtened connector and slip the short piece of shrink tubing over the repair and shrink it. The smaller the fix area, the better movement the wires have for the centrifical advance.

[sparkfly88]

Well I did the fix using the repair tip.

I soldered and heatshrinked it.

Still didn't fix it.

I did adjust the spark advance to make it run better. Seems all the way counter clockwise makes it run pretty dang smooth.

Still likes to hit a wall at 5-6k rpm.

Turning it to prime helps ( I think) but not much.

The throttle is still sensitive, I only have an inch or so of travel to work the whole bike.....

[sparkfly88]

Installed cam chain auto tensioner, kept petcocks at prime position and I got the RPMs at the highest they have ever been, and I actually think I hit the rev limiter!

[motoman]

Installed cam chain auto tensioner, kept petcocks at prime position and I got the RPMs at the highest they have ever been, and I actually think I hit the rev limiter!

no rev limiter on these motors

[motoman]

Well I did the fix using the repair tip.

I soldered and heatshrinked it.

Still didn't fix it.

I did adjust the spark advance to make it run better. Seems all the way counter clockwise makes it run pretty dang smooth.

Still likes to hit a wall at 5-6k rpm.

Turning it to prime helps ( I think) but not much.

The throttle is still sensitive, I only have an inch or so of travel to work the whole bike.....

Rotate that unit back to the factory setting where the screw marks were originally. No need to change it. You've got timing so retarded it'll never catch up, so to speak. If that advance unit doesn't freely move(floppy loose), that'll have the same thing happening.

[bikerphil]

CCW is timing advanced. Just be sure to listen for detonation, if it pings some, dial it back a bit.

[sparkfly88]

Well, under load, same thing, hits a wall at 5K rpm.


I decided on my way back home today that I'm out of options in my mind...

I dropped it off at a local bike shop to pray they can figure it out

[bikerphil]

Are you running those pod air filters on there? Some of them have an inner lip that obstructs the air jets in the back of the carb inlet. JAT

[sparkfly88]

Nope, OE airbox with an antique K&N that came with it

[bikerphil]

Did you check that mechanical advance unit under the left ignition cover. The weights and springs can freeze up from sitting, keeping the timing from fully advancing at higher RPM, JAT

[natemoen]

You need to unclip those wires and check them all better. If one is broken others most likely are too.

[motoman]

You need to unclip those wires and check them all better. If one is broken others most likely are too.

Hope that works out for you taking it to a shop. Unfortunately, that likleyhood is a stretch at best.