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cleoent · Post by **cleoent** » 10:57 am Dec 03 2007

I need some more help as i can't seem to get my tuning woes fixed...

2001 kdx220
fresh top end with wiseco
boysen dual stage power reeds
stock air filter (cleaned), de-snorkled, airbox lid drilled
fmf pipe and silencer
145 main, 42 pilot, needle on 3rd down
elevation of 0-3000 feet

Here's my symptoms, the bike starts and idles beautifully. BUT, my first gear is mostly useless, i can go about 3 mph before it starts sputtering like i've hit a rev limiter, 2nd gear the same, 3rd gear i can pick up some speed and get into the upper rpms but 4th gear is when it really starts to move and i can use the entire power band. What does this mean? Why cant i use the entire power band in the lower gears? first is non-existent.

Any tips? I haven't touched the air screw... I dont know what to do there. No space to do a plug chop.

KarlP · Post by **KarlP** » 12:12 pm Dec 03 2007

Seems like I used a 140 main for the same setup, same bike.

try moving the clip up to the top groove. If life improves, your main may be too large.

You really need to find a place where you can get a plug chop or two in, once you get it in the ballpark.

I think a 145 main is too rich.

canyncarvr · Post by **canyncarvr** » 12:21 pm Dec 03 2007

Does the choke work? Meaning..can you tell a difference with it on from off?

Does 'start beautifully' mean you don't even need to use the choke? That's not 'beautiful'. That's a problem.

Verify that your reed block is installed correctly:

Note the tab on the lower left corner? Make sure it's not on the UPPER right corner. This piece installs 180º off just as easily as correctly.

That alone (reed block installed wrong) won't alone cause all of what you indicate is happening, but may be part of it.

Whether or not a 145 will be too rich on the main (at sea level?) isn't the point, yet. Same for the #3 clip position..but neither is going to cause blubbering as indicated..just off-performance and maybe a plug foul from time to time.

Who did the top end? What's the arrow on the top of the piston indicate?

IdahoCharley · Post by **IdahoCharley** » 01:37 pm Dec 03 2007

canyncarvr wrote: What's the arrow on the top of the piston indicate?

Good write up of ideas CC. My bet is the arrow is wrong direction

canyncarvr · Post by **canyncarvr** » 02:32 pm Dec 03 2007

I know it's a good day when IC agrees with something I said!!!

He's one fart smeller!!

cleoent · Post by **cleoent** » 02:39 pm Dec 03 2007

Arrow is pointing the right way.

i'll check the reeds, i was careful to put them the right way, i'll also lean it out a bit and put the 140 back there. So you guys think, the problem is too much air not enough fuel not the other way around?

Will give it a go, thank you :)

canyncarvr · Post by **canyncarvr** » 03:23 pm Dec 03 2007

Don't take the questions personally. The point is solve the problem. The top-end having just been done, the most likely culprit is something amiss with that process.

Example:
It's not the reeds being in the 'right way' that I questioned. When I ask about the reed block, and you respond with how the reeds were put in..it makes me wonder. Again no one is here to irritate or piss you off OR denegrate your ability..but to solve the problem.

Old story...but I spent WEEKS once trying to sort out a rider's troubles...lot's of emails back and forth..only to find that his air screw was black in color..and made of nylon.

That's what he thought, anyway.

It's impossible to tell where 'the basics' start with any particular question. To overlook the most obvious because it's too basic is ..well, basically a mistake.

BTW..'Arrow is pointing the right way' is incorrect. It doesn't point to the right!

cleoent · Post by **cleoent** » 04:07 pm Dec 03 2007

no sweat.

Reed block is pointing the right way as well. Arrow is the right way...

do you think i should dump the stock filter and go with a uni? Could that be the culprit? It was a lot worse this weekend up in the higher elevations that i ride in (2K+) than it usually is at my normal <1k feet elevations.

but even at <1k elevation it's not running right.

cleoent · Post by **cleoent** » 04:08 pm Dec 03 2007

btw- choke is needed to start in colder conditions. (cold starts)

canyncarvr · Post by **canyncarvr** » 05:48 pm Dec 03 2007

IF the condition is due to being too rich...it's WAY bad. It's not something a 142 vs: a 145 is going to fix.

How 'bout a stuck float? Any evidence of the 'too full' tube out of the carb peeing?

There isn't anything wrong with a properly cleaned and oiled OEM filter. Run it for a minute with it off..see if it just improves, or gets altogether better.

A couple steps back....

When did this start..what was done since it ran fine..how long has that been?

Although this isn't a classic KDX problem..it DOES sound a LOT like a classic XR problem..and that's a faulty exciter coil.

Was the rotor off?

Do you happen to have a high-tension (ignition) tester? One'a those LED devices you clamp to the spark plug wire and read thousands of volts in the wire?

Maybe take the rag OUT of the carb throat that you put in there during the rebuild proces to keep dirt out!

FTR...the arrow points toward the front of the bike...the holes in the skirt are toward the carby.

....for those that din't know there WAS an arrow on the piston. ..usually.

cleoent · Post by **cleoent** » 06:25 pm Dec 03 2007

maybe i'll pull the head cover and just make sure about the piston, i'm 99.9 percent certain it's pointing towards the exhaust.

Let me play with the jets and the air screw and see if that fixes it up.

Like i said, it was a lot worse this weekend in the higher altitudes than it usually is.

canyncarvr · Post by **canyncarvr** » 07:04 pm Dec 03 2007

Head cover?

If that means the head...don't.

Pull the pipe off...or take the reed cage out. Check it that way.

Re: '..whole lot worse...'

This: 'BUT, my first gear is mostly useless, i can go about 3 mph before it starts sputtering like i've hit a rev limiter, 2nd gear the same...'

..is worse enough! It don't have to GET worser'n that!!

cleoent · Post by **cleoent** » 07:12 pm Dec 03 2007

perhaps i wasn't clear...

that's what it was like this weekend in the higher altitudes, normally it's better.

cleoent · Post by **cleoent** » 12:12 pm Dec 04 2007

what does the air screw do? Can someone give me a good baseline?

Around where i normally ride <1k elevation, my mid throttle response is my only problem, i have full use of my power band if i give it full throttle. I've tried the clip on the #2 and #3 position, no luck, thoughts?

canyncarvr · Post by **canyncarvr** » 03:29 pm Dec 04 2007

Now I'm lost.

This:

BUT, my first gear is mostly useless, i can go about 3 mph before it starts sputtering like i've hit a rev limiter, 2nd gear the same...

..has nothing to do with this:

my mid throttle response is my only problem

...and <1k to 2k+ el change isn't going to make that difference.

The air screw adjusts off-idle response. That said, every circuit in the carb effects every other circuit to some extent. A way-off main will mess up your idle for example.

Adjust the air screw for best response. Basic method: 2nd gear, under load (say up a grade), walking speed, crack the throttle from idle to 3/8-1/2 or so.

Rule of thumb is: Air screw more than 2 out=pilot too rich. Less than 3/4=pilot too lean.

In an unmodified carb that is jetted 1/2-fast, you will be in the 1 1/2 to 1 3/4 area.

Don't jerk the measurement around..don't change the air screw from 3 out to 1 out and expect an immediate change in the above test method. 'Clean it out' a bit from one adjustment to the other.

The result you're after is no hesitation..no BOOO-WAH, no diving front end. The bike should just 'GO'....jump like a bunny wabbit.

cleoent · Post by **cleoent** » 09:04 pm Dec 04 2007

yeah i can see my thread is very poorly written, i apologize for that. Even though you guys are having to sort through my mess you've given me great suggestions.

I moved the needle up to the 2nd clip, and i put in a 142 today. I only rode it around my block but floored in second gear the front end wanted to come up even from a slow roll, excellent.

Does the wiseco piston and rings take a longer time to warm up? I noticed this weekend and even today that the bike will take a long time to run properly, 5 minutes or so.... is that normal? Or is that a sign of another problem?

cleoent · Post by **cleoent** » 09:09 pm Dec 04 2007

I'm also thinking about going and buying a new spark plug, i think i'm on the original one... should i just get the exact same one??

AwfulSmokey · Post by **AwfulSmokey** » 09:15 pm Dec 04 2007

cleoent wrote:I'm also thinking about going and buying a new spark plug, i think i'm on the original one... should i just get the exact same one??

NGK BR8ES

Post by **Indawoods** » 09:17 pm Dec 04 2007

Yes... you should always thoroughly warm up your bike when running a Wiseco piston!

Post by **Mr. Wibbens** » 09:31 pm Dec 04 2007

cleoent wrote:I'm also thinking about going and buying a new spark plug, i think i'm on the original one... should i just get the exact same one??

The original one??!

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more tuning questions

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