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Discussion Starter · #1 ·
Hi all!

Finally got my Xr650 converted for street duty.

Took it for its first voyage and had a clitch i cant figure out. At a cruising speed say 2-3 gear around 30 mph, if i try to mantain that speed, its hard to do so. The bike either wants to go faster or slower.... Kinda jerky ya know?

I do have a edelbrock carb on it, that is jetted for a aftermarket exhaust that i have, but is yet on the bike (still rocking the stocker) Think that could be the problem?
 

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There are so many things that can induce this, such as throttle tube, too much chain slack, to low of a gear ratio, et. But the one that pops into my head, especially with you saying you just recarbed and rejected, is the jetting. If it's lean, or even rich, when you get back on the throttle it'll clear and pull hard. The best thing for you to do is dig deep (for funds) and find a local dyno operator that is good at what he does, and he'll set you up and your bike will never run better. Sometimes you can get really lucky, being on a forum for the exact bike you have, and find out what the top tuners are using, then just do what they already spent their time and money finding out what works best for them. I got super lucky on my 2010 KTM 530. I brought it home, and there was a serious flat spot. I did a YouTube search for KTM 530’s and there’s a tuner for Two-Brothers racing with my exact bike doing a rejet for one of their endcans! He changes out the rear knobby to a street tire so it hooks up better on the dyno, does a run, and comes up with 37hp. Then here’s the amazingly great part. He rejets and changes the needle in the carb, but also tells you what he’s using. He then puts his endcan on, reruns it on the dyno, and comes up with 50hp!!! So for twenty dollars’ worth of parts, and a half hour work, my bike runs fantastic now. That’s what a good tuner can do for your bike. You really have no idea how bad it’s running until you have it running the best it is capable of. Take it in, or find someone with the right setup.
 

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Hes got an Eddy, no jets and a needle that can be adjusted to the moon...

You do have the needle adjuster on the outside of the carb installed right? You get any black smoke if you whack the throttle from off idle? I would guess you have the carb set up a bit to rich...

When i got mine up and running here is how i set it up.

1. Disconnected the pumper arm
2. With the pumper arm removed i went for a long ride tuning session. Making small adjustments to the needle to get it in just the right spot.
3. Hooked pumper back up
4. Another long ride tuning session. Adjusting the squirt to get the best out of the pumper side of the carb.
 

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Discussion Starter · #5 ·
thanx guys!

There seems to be a new problem now. The carb is just pissing gas. i went for a ride and the bike kept dying. After a couple kicks it finally started to run. I did a couple of pass's and everything seemed better. I then looked down and there was a puddle of gas under me. The carb was just puking gas out of the over flo. It would only stop when i turned the petcock off.

Any idea? Im thinking the float is stuck?
 

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thanx guys!

There seems to be a new problem now. The carb is just pissing gas. i went for a ride and the bike kept dying. After a couple kicks it finally started to run. I did a couple of pass's and everything seemed better. I then looked down and there was a puddle of gas under me. The carb was just puking gas out of the over flo. It would only stop when i turned the petcock off.

Any idea? Im thinking the float is stuck?
I'm thinking you're right. But what caused it to stick is the question. Must be something causing it to stick, unless the needle/seat is worn.
 

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Discussion Starter · #8 ·
ok so.....

got the eddy carb off. I put on my oem honda carb in the mean time so i can still ride it (damn throttle is sticky though, any ideas?)

As for the eddy carb im going to tear into the bowl tonight. I bought it used (almost new just 500 miles or so) but they said it was jetted for a aftermarket exhaust.

Im still running the factory exhaust, so will i be able to tune this thing to run correctly after i clean the bowl?
 

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I had a similar problem with my XR, I have the Edelbrock as well, and when cruising 30-40 mph, I'd be on the gas a tiny bit to maintain speed, and the bike would surge, and jerk. I found out the "pump shot" screw was shooting way too much fuel for the rpm when I would keep the throttle open a hair. I backed off the screw counter clockwise in 1/8 turn increments (its the small screw with the jamb nut located on the bowl facing the exhaust) until the problem went away.

However I have a fuel leaking from the overflow as well. This happened only after I replaced the pumper assembly, and the needle and seat. I'm assuming the float is set too high, and the little "flap" on the float needs to be bent. it only leaks when the bike is off, and leaning on the kickstand. My bike still stalls sometimes too, only when sitting at a stop though... could have something to do with the float level.
 

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Discussion Starter · #10 ·
ok so im going to try and put the eddy carb back on.

What is the screw for on the bowl? That screw is WAY out, is that screw some kinda bowl adjustment?

Where should it be set at?

Also the screw thats on the top of the carb, what does it do? Where should that be set?

I have no instructions with this thing. So im going at this blind.
 

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Discussion Starter · #11 ·
ok Here are the two screws screws im talking about:



#1- This is the one on the bowl. Where should it be adjust to? Right now its VERY far out.

#2- This the other screw on the top. My screw is red in color, with with a spring. Where should this be adjusted to?
 

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http://www.edelbrock.com/automotive_new/misc/tech_center/install/off-road_carbs/Off-Road_install.pdf

Here is a manual for the Edelbrock to get you started... The screw on the bowl is the pump shot screw I mentioned in my post. This adjusts how much fuel the accelerator pump squirts... if yours is way out, its possibly too lean. I think mine is set around 3 turns out from all the way in... The top screw should be 15-17 turns from full rich (all the way in) to get in the ballpark...

Either way, go through the steps in the manual, and you should be good to go!
 

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If you're uncorked with no aftermarket exhaust or opened intake then you'll probably want to start at 19 out, then try 18 followed by 17. Find the one that pulls well from about 1/8 throttle with a nice roll on, not wacking the throttle. Then fine tune to get the best steady state cruising speed feel, no jerky behavior.

From there you'll want to go in a 1/2 turn at time on the pump screw and test the bike in 2nd gear fast roll on just off idle. You want just enough pump so that the bike doesn't bog and responds with a crisp hard pull. Going slightly too rich will generally result in a slower build of acceleration.
 

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Discussion Starter · #14 ·
thank you so much gentleman!

That makes sense why it was poring fuel when ever i cracked open the throttle now. The pump was to rich from that screw being to far out.

Im going to put the eddy back on tonight and hopefully take it out for a spin and correct the issues and get her tuned.

So should i start with the pump screw out 1 1/2 turns then?
 

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Should be a good spot to start.
I found mine to be VERY sensitive to adjustments. A little one way or the other made a big difference in the way it picked up.

Now that its dialed in though, i have not touched the thing, solid as a rock.
 

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Discussion Starter · #16 ·
Alright! Finally some good news....

Put the eddy back on. Set the pumper screw to one full turn and one half turn out. Left the top needle screw as is for now. (just wanted to at least get her started)

Couple of kicks and bam! She lives!

Took her for a short spin, and man does she jerk and hesitate! Some definite tuning needed! But at least she runs and is not pissing fuel.

As for the the top needle screw. When you guys say 18 out? 19 out? 20 out? How do you know where to start? Which way is out and which way is in? Can i turn it in far enough that it will stop, then i can turn out 18? I guess what im asking is how do i get to zero? so i can count 18/19/20 out?
 

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Alright! Finally some good news....

Put the eddy back on. Set the pumper screw to one full turn and one half turn out. Left the top needle screw as is for now. (just wanted to at least get her started)

Couple of kicks and bam! She lives!

Took her for a short spin, and man does she jerk and hesitate! Some definite tuning needed! But at least she runs and is not pissing fuel.

As for the the top needle screw. When you guys say 18 out? 19 out? 20 out? How do you know where to start? Which way is out and which way is in? Can i turn it in far enough that it will stop, then i can turn out 18? I guess what im asking is how do i get to zero? so i can count 18/19/20 out?
To get to zero, turn the needle screw all the way in, this would be counter clockwise. Then count each turn out clockwise...
 

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Discussion Starter · #18 ·
ok.

First tuning session complete. Right now the jet needle is at 21 or 22 (lost track) Seem to be riding ALOT better. I can cruise now with little to no jerking. Im done for tonight. I will continue tomorrow afternoon.

Starts are still ruff, but im sure that because i have the pumper not hooked up for tuning.

Question- As for the clicks for the top jet. Im at 21/22 can you make small adjustments on the clicks? Like say a half a click? Or just full clicks?
 

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Discussion Starter · #19 ·
ok got it tuned :)

But.......

Sumpin is up with the throttle. When i twist it and let go it stays it doesnt really snap back. Its VERY slow on returning......

What can i do to stop that? There seems to be no adjust on the cables?
 

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ok got it tuned :)

But.......

Sumpin is up with the throttle. When i twist it and let go it stays it doesnt really snap back. Its VERY slow on returning......

What can i do to stop that? There seems to be no adjust on the cables?
Sounds like the throttle return spring, or the blade type spring for the slide is worn. I have no idea if these items are available anymore. Part #12 or part #17 here:http://www.edelbrock.com/motorcycle/carbs/carb_internals.pdf

Mine kinda does the same thing, it doesn't return very fast, but it works.

Check for binding in the cables too if you haven't already.
 
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