I think I am done..

[Crazcnuk]

Other than all that has been mentioned already, I had the same problem and it was #2 carb idle (sync) was opening the plate allowing vacuum to pull on the vacuum advance at idle. It would rev up to 2500-3000 too.

The other thing that can cause this is a vacuum leak on one of the cylinders... Check the hoses and those little caps on the blocked off vacuum ports.

[thewiz]

Jat ..

I have seen a slightly bent throttle lever on the carb rack itself, where the cable connects, become jammed on a misplaced clamp from a nearby carb holder not allowing full throttle movement ..

[BigRed]

Some things to check

I haven't read through your previous posts, but here are a few thoughts on what you might want to look for if you haven't already:

Check your pick-up coil wires and vaccuum advance mechanism. If it won't rev over 5500 rpm, this would be the spot I'd look first.

Check for vaccuum leaks; spray some starter fluid or WD-40 on your intake boots and carbs and see if the revs pick up.

Actually... now that I see those two things side be each, if the vaccuum advance line or diaphragm were leaking, it may cause both these problems.

Check your vaccuum synch tubes on the intake boots; I read a post from another memeber where one of these tubes had pushed into the boot, and was messing up the flow inside.

Didn't want to go into details on how to do these checks in case you already have done them or know how to, but if you have any questions, post back!

Good luck! Glad you've found some local help.

[GARTHXS]

you are in good hands

The Wiz is a true guru not just someone who fluffs

[Shawnb]

i am almost done

Clean your carbs, wait hold on check for spark, and clean your carbs, clean your carburators.

[Rettic]

Just recently, like a few/two months ago, Ultrasonically cleaned them. Just checked em two days ago and still looked real good. I will be checking for vacuum leaks tomorrow. Got a few other tips to check/try. Need to reset the idle screws to see if that helps. This weekend is seeing alot of work being done to it. So we will see. I am optimistic thanks to all the comments.

[Rettic]

Update

Howdy all,
Well thanks to thewiz, I know where my problem is. He had a bike he was working on for someone else, and had them bring me their carbs which were known to be good and put them on the bike. Well it appears my beautifully clean carbs are not right. They seem to be FUBAR'd. The loaner set worked perfectly. So i know where to swing the sledge hammer. I have 2 sets of carbs here. The ones that came with the bike got 2stuck idle mixture screws. They would not budge with all the tips and tricks on here. I tried.... yeah I did... tried to drill them and messed em up more. So I bought a 2nd set. used them, they worked for the most part, just top end issues. Then the compression came back and messed the sync up and exposed other problems. So I am going to be taking the internals from the original set and putting them in the new set to see if that helps. I will let you all know... I love the sound of this bike, I have since the very first time ever started it up. Well heres to 4 hrs of switching parts. I will update when it gets done.

PS Compression on all 4 without carbs and without spark plugs is 185. Yeah I stumped to why it is so high. But... they are all the same so Seafoam in the oil got the ring unstucked.

[thewiz]

Right on !!

That's really good news. Chris ... at least you know the set you picked up on here is bad ... this whole deal has reminded me of the Crazycnuk neverending carb thread from hell . experience. Learned from that thread ... but OMG ... poor Crazy ... 'bout made him crazier, I think ... lol.

For the high compression issue, try removing all the plugs and pour an oz or two of MMO down each hole and roll the motor over by hand a couple of times then let it set with the MMO on top of the pistons for the next week while you mixing and matching your carbs back together. Will kill off any carbon build up pronto.

[DGXSER]

Nice work figuring out the issue!!! Good job on the helping hand Wiz!

Carbs can be the demon of a lifetime, but once you get them right, it feels SOOO good. Keep working on them and you will get there.

[Crazcnuk]

It's almost worth having a 'known' good set of carbs on hand at all times. Takes a TON of guesswork out of it.

[clcorbin]

It's almost worth having a 'known' good set of carbs on hand at all times.

Just don't leave any gas in them when they are not in use or they won't be 'known' good for long!

[Crazcnuk]

The only way I know to keep them 'known' good, is to have them on the bike you use the most.

[3Phase]

We'll get it.

Way to go, Wiz!


Regards,

Scott

[thewiz]

Yerp, Craz ....the carbs were 'known good' alright ...

They came from the bike that I had just sold a few days earlier and the new owner hadn't taken home yet. The bike is here waiting to get a 4/1 put on and re-jetted by me. I was able to convince the somewhat skeptical new owner, who lived near Chris (Rettic) in Charlotte and who was here visiting his new Eleven on Saturday ... lol ... to 'lend' Rettic the carb bank for a few minutes to try on and probably illuminate what I believed (and Chris probably feared) was most likely the true problem ... lol. We'd discussed about everything else over the phone for a couple of hrs. and Chris is a very competent wrench with the good tools ... so .... that's pretty much what it had to be. A bad set ... kinda like Craz's, IIRC... mix and match parts? ...who knows? ...that part remains unknown still.

Real thanks go to the new owner of my (former) gorgeous F for allowing it to happen.

It worked out pretty good this time.

[Rettic]

Errr

I changed out everything internal. Made sure to clean anything that looks dirty, still pretty much perfect on the inside. I put the parts from the other set in, and get them back on the bike, it starts first try. Awesome cut choke down let it warm up. Cool, take choke off completely. Idles... for the most part, rough, to be expected. At least I have some vacuum to adjust sync with, not much. But some is better then none. Get them synced. Throttle it up, it hangs, but the sync is nice and even. So then I check the mixtures, tweak em. Find out #1 is the culprit this time. The header is only warm, not hot. Pop diff spark plug caps off, 1 does nothing, 2 it dies, 3 it dies and 4 not quite but stumbles. Color tune on 1 confirms, no fuel seems to be getting through. I adjust mixture in and out with no change.

So I get to pop those carbs off again and figure out what is wrong with #1. Good news is that it does run a bit better then before. Well till tomorrow. Hope it is just something clogging up something else and a good squirt of carb cleaner and a ton of air from the compressor takes care of it. Still stressed over it, but getting better.