[ctandc]

Okay... that does point back to carbs then...

I'll know by lunch time tomorrow hopefully.

[ctandc]

Almost ready to throw in the towel

I took off work today. Pulled the carbs, took 'em apart and CLEANED EVERY NOOK And CRANNY. Pilot Jets, needles etc etc...all cleaned. All passages clear. Put 'em back on....same thing pretty much....#4 and #3 firing some (according to the inductive timing light) but those exhaust pipes are staying cool, even after I took it down the road and ran it a good bit.

So next up I swapped the signal generator from the 91 Kat 600 (which was running just fine before the engine swap BTW) onto the 750 motor. Test run...same thing.

Then I swapped to BOTH of my original coils from the 600 engine. Same thing.

Removed the 5 degree advancer and installed the stock 750 advancer.

Same thing....seemed a "Bit" better but at this point I can't tell what's what. #4 and #3 pipes STILL COOL to the touch.

So then I swapped plugs, to the new Irridium plugs I bought the first time....cleaned 'em off, installed 'em and it got worse. Backfire at idle...

Now I do have an exhaust leak where the mid-pipe hooks to the header, as I butchered my new $20 exhaust connector / gasket and need to get a new one now....but not enough of a leak to cause it to run like CRAP.


Well next up, tomorrow morning, I'm swapping the stock main jets, and stock needles / clips in to see what I get.

If that doesn't do it....I honestly don't know. I'm pulling my hair out right now with it.

The ONLY other possibilities I can think of:

- The 91 petcock has two fuel outlets... I've got one plugged since the 01 carbs have one fuel line...maybe somehow this is starving the two carbs on the end? (#4 and #3)????/

- I had a couple of wires that rubbed through (Causing the bike to trip the main breaker) before I started the engine swap. I found those wires in the main harness and I covered them in liquid electrical tape AND wrapped 'em up....maybe another messed up wire somewhere



I'm tempted to swap in the ENTIRE wiring harness from the 01 750 Kat, which would include the CDI, swapping LH and RH control + installing the dual throttle cable setup + splicing the wires to work with the pre 98 gauges.

I'm grasping at straws now. It's going to be Fall before I get this thing up and going..................

[steves]

A Back-fire or backfire is an explosion in the exhaust manifold, carburetor/throttle body or air cleaner of an internal combustion engine. Although an explosion in the engine's exhaust manifold or exhaust system, is often referred to as a backfire, it is actually an afterfire.

Common causes of back fires in the intake manifold are bad spark timing, or incorrect (usually lean) fuel ratio.

http://en.wikipedia.org/wiki/Back-fire

Okay... so you started at 4 turns out, and had backfires... then went to 3.5 turns out (leaning the mix) and it got worse.

So.... my WAG is try 4.25 turns? Or alternatively... go back to the stock jets and stock positions for the A/F screws.

Did you drain your airbox? I don't remember.... drain it if you have not, and report back on the contents and approximate quantity.

I'll assume it's not timing related, as you've had two separate sets of coils on the bike, and it's probably not wiring because it's not like it "cuts out" it's just back firing.

[ctandc]

A Back-fire or backfire is an explosion in the exhaust manifold, carburetor/throttle body or air cleaner of an internal combustion engine. Although an explosion in the engine's exhaust manifold or exhaust system, is often referred to as a backfire, it is actually an afterfire.

Common causes of back fires in the intake manifold are bad spark timing, or incorrect (usually lean) fuel ratio.

http://en.wikipedia.org/wiki/Back-fire

Okay... so you started at 4 turns out, and had backfires... then went to 3.5 turns out (leaning the mix) and it got worse.

So.... my WAG is try 4.25 turns? Or alternatively... go back to the stock jets and stock positions for the A/F screws.

Did you drain your airbox? I don't remember.... drain it if you have not, and report back on the contents and approximate quantity.

I'll assume it's not timing related, as you've had two separate sets of coils on the bike, and it's probably not wiring because it's not like it "cuts out" it's just back firing.

You're correct, it's an afterfire.

I'm going to remove the Ivan's kit and go back to stock on the carbs and go from there.

And maybe I posted something that didn't come out right...the A/F settings never effected anything. It's run like poo the entire time.

[steves]

But is there anything in the airbox?

[ctandc]

But is there anything in the airbox?

Besides the stock air filter? Nope...

Clean..........

If the jet kit removal doesn't do it, I might have a bonfire tomorrow

The worst part about it is, I could swear it's an ignition / electrical issue.

[hardlydangerous]

if you have the other harness you can try it befoe you install it, Just zip tie it ti the frame and unplug the old wiring and plug everything in to the 01 harness...
I'm can't say for sure that's the problem but I can't leave it alone either... I'm guessing that's your problem. With the 01 complete it was fine and it was not until you mix matched wiring and electronics...

[VifferJim]

The ONLY other possibilities I can think of:

- The 91 petcock has two fuel outlets... I've got one plugged since the 01 carbs have one fuel line...maybe somehow this is starving the two carbs on the end? (#4 and #3)????/

...

Okay, this has been bothering me (mostly because I mentioned it in reverse a few posts ago but said "nnnaaaah, prolly not) and probably has nothing to do with anything. But, if you reset the carbs back to factory and get nothing; swap the harness and still get no love... I gotta wonder if this isn't somehow the problem.

I wonder... did you say you already filled all four bowls manually?? If not, wouldn't pulling the tank, a clean set of plugs and four full bowls be enough to prove or disprove this as the problem.

[steves]

Besides the stock air filter? Nope...

Clean..........

If the jet kit removal doesn't do it, I might have a bonfire tomorrow

The worst part about it is, I could swear it's an ignition / electrical issue.

Nothing came out the drain?

[ctandc]

Nothing came out the drain?

Nope the drain was / is empty. I'm using the airbox off the 01 Kat, and it had some crap in there when I got the parts bike home (when it was running) and I drained it and cleaned it out before I installed it during the swap.

[ctandc]

Finally!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!

WOO HOOO!!!!!!!!!!!!!!!!!! we HAVE A WINNER!!!!

Today I removed the Ivan's jet kit (Which I confirmed was installed CORRECTLY) and put back the stock needles and the stock main jets.

I also threw in ANOTHER set of new NGK plugs (3rd set so far on this swap).

Also swapped back to the 750 coils since they tested good. (As did the 600 coils).

Got the carbs / airbox back on.... prime for a bit...BAM fired right up, no back or afterfire, and you can DEFINITELY tell when it's hitting on all 4. Wow....took it down the street...HOLY CRAP...it runs GREAT.

Just got done breaking out the Morgan Carbtune and synced up the carbs. I'm uploading video's of both so I can share my joy.

Now I'll install the 5 degree advancer back...and see how it runs...

I'm going to call Ivan from work Monday...I'm stumped why his jet kit caused that much trouble..and I chased my tail over that FOREVER.

THANKS FOR THE ALL HELP GUYS IT'S MUCH APPRECIATED


Video of it first cranking up after going back to stock with carbs
[YOUTUBE]http://www.youtube.com/watch?v=yl6Mq4L1qTc[/YOUTUBE]

Right after carb sync.. I'd say they're pretty close

[YOUTUBE]http://www.youtube.com/watch?v=6c9g8WJwhyI[/YOUTUBE]

[steves]

Awesome.

So.... are you going to try the Ivans kit again?

[ctandc]

Awesome.

So.... are you going to try the Ivans kit again?

.............................................Yeah probably...

[VifferJim]

Outstanding!! Congrats.