TOPIC:

wrote:

wrote:

You can run it on prime until you know you have everything working.






 

This is essentially like "ON" on a normal petcock?  I've almost got everything back together and would love to ride tomorrow if possible

Yes.

Well I got it running.  But it idles at like 5k.  I've tried adjusting the idle screws and that doesn't get me anywhere.  The throttle cable doesn't have any tension.  I don't know whats going on.  I have basic zero knowledge of how to troubleshoot a carb.  Can anyone advise me?  Based on the poor experience I've had with Speed Moto Co's kit, I wouldn't be surprised if they put in all the wrong jets and setup it blindly.

Do you have them mounted in a way that you cannot look into the inlet of the carbs to see the slide?  (Whatever you do, don't look in closely while running. Only when stopped, or from far behind the bike.)

You should be able to see the slides close all the way as you turn out the idle-speed screws.  If the slides don't drop all the way, then there must be something hanging them open.  Since you have a 3-piece throttle cable, there are several pitfalls to watch out for. It's not enough to see slack in the main cable.  Both secondary cables must be slack too.  That is what that adjuster is for where the cable goes into the top of the carb.  If the adjuster is all the way down, and the cable is still not letting the slide bottom out, you will have to shorten the cable housing on the secondary cables (as evenly as possible).  It could also be that the secondary cables are not seated all the way inside the splitter-slide.  That is the cylinder that the three cables all go into.

Dumb question, but do you have one or both of the chokes on?

wrote:

Dumb question, but do you have one or both of the chokes on?
 

No.  And no dumb questions here.  Everything is game.

wrote:

Do you have them mounted in a way that you cannot look into the inlet of the carbs to see the slide?  (Whatever you do, don't look in closely while running. Only when stopped, or from far behind the bike.)

You should be able to see the slides close all the way as you turn out the idle-speed screws.  If the slides don't drop all the way, then there must be something hanging them open.  Since you have a 3-piece throttle cable, there are several pitfalls to watch out for. It's not enough to see slack in the main cable.  Both secondary cables must be slack too.  That is what that adjuster is for where the cable goes into the top of the carb.  If the adjuster is all the way down, and the cable is still not letting the slide bottom out, you will have to shorten the cable housing on the secondary cables (as evenly as possible).  It could also be that the secondary cables are not seated all the way inside the splitter-slide.  That is the cylinder that the three cables all go into.
 

I guess tomorrow I can remove the carbs from the intake boots and see if they close all the way with the idle screws out.  I'll have to check for slack in the lower two cables.  I have the adjusters on the top of the carbs screwed all the way down to provide extra length.  How can shortening the cable help me here?  Seems to me the length isn't long enough.

Again I'm not familiar with carbs, I'm a total dumbass when it comes to them.  But the small, thin rod that is in the middle of the cylider slide that has about 6 possible positions for adjustment.  Could it be that?  The plate that sits loosely on the bottom of that cylinder. Seems the small rod adjusts the height of that little plate that is almost pacman shaped if you follow me.

I should also say,  there is a noticeable amount of difference in the RPM range when I just move the gas tank around.  Anything going on here?  It seems to me I need to make all my fuel lines strictly below the outlet of the petcock.

Not sure if any of this will be of any help or not.  I would assume that you have routed the throttle cable along the frame back bone under the tank, if moving the tank around changes the rpm it could be that the tank is pinching or pulling the cable in a way that changes its length.  As to cables they sort of work the opposite way one might think they do.  
By making the outer cover longer, you shorten the inner cable length. By shortening the outer cable you increase the inner cable length. 

I said shortening the cable housing, not the cable.  As gd4now described, shortening the housing effectively gives you a longer cable for additional slack, in case that is what you find you need.

Also, I agree, if the cable runs under the tank, and moving the tank changes RPM, the tank may be interfering with the cable and causing movement and/or preventing the cable from allowing the carbs to close all the way.  Those 3-way throttle cables are finicky. They do not like being disturbed.  It throws off the sync and can bind them open as you describe.

Since I had to build that ugly brass tee that was shown in a previous post, I have a considerably extra more fuel line than what is normal.  Is it okay if it loops above the petcock opening?  I had the brass tee zip tied to the frame, so gas would have to travel up.  My thought was that it wouldn't matter because the engine would create a vacuum and suck it in.  Or does it really need to directly feed by gravity?

Float bowls are vented so there is no vacuum in the bowl chamber.  The fuel tank is also vented.  Only gravity pulls the fuel down.  As long as all of the fuel line is below the fuel level in the tank, gravity will do its job.  The only time there could be an issue is if a paper filter is used for the fuel.  They sometimes need more than gravity pressure to push fuel through.  The preferred filter type would be a scintered metal or metal screen filter.  Doing loops can trap an air bubble, but as long as there is no other obstruction, and enough fuel in the tank, gas will dribble past the air bubble.

It's easy to check.  Just pull a fuel line off at the carb and see if gas pours out.  Or better yet, open the drain on the carb bowl if it has one and see if gas pours out.

Found the culprit.  Just ziptieingthe cable to the frame was enough to cause the engine to rev so high.  I snipped the zip ties, started it, and bam! the engine was running at 1k rpm.  So now I'll just have to dial in the idle speed identically, which is a pain with them so tightly in there.  But I'm glad I have it fixed and I can ride today.  Gorgeous day!

Just another thing I hate about the Speed Moto Co's kit - the throttle cable is too long!  That's why I had it zip tied.  It's probably an extra 5" too long, I have a large loop coming out from my headlight to my throttle grip.  I'm going to have to get Motion Pro make me a new throttle cable.

Moral of this long ass story - which is still going on (we'll see how she actually performs now) - don't buy Speed Moto Co's kit.  It's not worth it.  It was supposed to be a simple bolt on, and it's not.  I'm going rip them a new one, maybe get BBB on them.