KDX 220 low end sputter

[jonooffler]

Hi thanks for the info I spoke to the guys at the local MX shop and they rode it it and came back saying that it was running rich and lean at the same time, when the the slide comes off the stop it runs rich to start with but then starts to lean untill it opens over the 1/4 to 1/2 mark, they suggested that I should lift the needle to the 3 clip and try that.So I now running 40-1 38 pilot 3rd clip and no snorkel I have yet to ride this setting but I will let you know how it goes.
As for the oil mix as I said the last owner claimed that he used 50-1 when he had it but I'm starting to think that he never took it out ( maybe he could not get it to run right) the problem I have is I do around 50% slow trails and 50% fastish road work so I'm not sure what to go with.
the silkoline oil I have says that it will work at 50-1 so I might drain the tank and re mix ( again :bang: ).
It's a real pain every one says how good this bike is at woods work but at the moment it's unrideable in low speed/rev work which is the sort of riding I do I would be nice to ride one which is sorted just to see if it\s the sort of bike that I'm looking for. I'm starting to think maybe a 4 stroke would be better for me.
Jono

 

[NCFRC]

I couldn't wait untill the weekend so I mixed up a fresh batch of 50:1 fuel.

First impression of a quick few mile ride is that it smartened it up quite a bit , not perfect but alot better than 40:1 . :cool:

 

[sr5bidder]

so Jono why have you not changed the main jet?, checked compression?, pulled the head to see if there is the stock piston in there with a crack (220's are known for doing this)????

also I don't know why there are 2 threads running on the same subject....

but anyhow as julien_d would tell you make shure the kips is not stuck open as this will cause your kdx to run like crap on the low rpms. with the kips open below 6000rpm the engine will have a lower compression ratio than it should

Please step away from the carb! :yell:

 

[jonooffler]

Hi there the problem is low speed running so the main jet should be fine it runs fine and pulls well in the high rev range.I have has two off road bike shops ( both MX based ) and they have both said the rings and piston are fine as the bike pulls so well, one of the shops ( a Kawa dealer ) said that the KIP valve is fine, so it has to be a carb/ jet issue or it's just one of those 220 problems.
As for the 2 threads one is from me the other is from another 220 rider with the same problem having spoken to other 220 owner they have taken a long time to get them running well.
I'm sorry that we both posted treads but I thought that was the idea of a forum.

 

[NCFRC]

The Maxima Oil I'm running has this posted on their technical information website . Most 2 strokes are over lubricated at idle , sufficiently lubed at half throttle and poorly lubricated at full throttle .

oil / gas ratios for various riding ,

Recreational 50-60:1
Moto X / Enduro / X-Country 32-40:1

 

[jonooffler]

Hi just tried out the new setting and it feels much better there is still a bit of a stutter but its better than it was 40-1 38 pilot clip 3rd and no snorkel.I think the oil mix might need to be changed I parked up to adjust the air screw and when I rode off after it had idled for a bit it had the stutter again,I'm going to ask around at silkoline and see what they say.
Thanks again all and sorry if I have been a pain over this.
Jono

 

[whenfoxforks-ruled]

Another circle jerk jetting issue erroneously made worse by messing with the oil ratio, duhhh? You was on the correct path down sizing the pilot. Start with replacing the float valve and checking the float height.

 

[jonooffler]

I must admit i don't like messing around with the oil mix to make the bike run, the label on the bike calls for 32-1 if the maker thinks that what it needs that what it should run with.
The float has been checked and is right, one of the dealers suggested going to a 36 pilot but that is way off what most 220 are running on, I might try to get one just to see how it feels.
Thanks for the input, I hope that I can sort this out soon I'm missing good riding at the moment.
Jono

 

[whenfoxforks-ruled]

Listen to the bike, not anyone elses, they are all different, just like people. Try the 36, see where the air screw adjusts to its highest rpm, with in 1/2 turn of the stock setting, good. If you still are scratching you're head, and blowing spooge, change the float valve. It seems you can grasp the lunacy of chasing a rich jetting issue by reducing the oil ratio, and there by putting even more fuel in. Have you read the plug for timing and correct heat range? This sites technical archives are number 1, and no one is hardly ever in there, its easier to assume they are the first with spooge?

 

[NCFRC]

When you throw out an question or comment you have to be open to receive all responses , if there based off knowledge / experience or just bull ****.

Good luck , you'll get it figured out.

 

[jonooffler]

Thanks for the support mate It's good to know that I have you guys out there.
I going to aviod messing around with the oil mix I want to stay at 40-1 I'm going to check the float level a few people have said about this I just need to know how to check it for my self as so call pro's have said it right but I don't know how they checked it.Jono

 

[whenfoxforks-ruled]

Long as you understand, reducing to 40:1 is making your entire throttle range richer. You will have to lean all the circuits. There is but 1 source of solid information, SAE documentation. Anything else is marketing and guy talk. There are builders, engineers, Doctors and scientists that have frequented this forum for over 10 years. Their input is in the technical archives, and the SAE websites. Awakening from years of blindly playing with dirt bikes, as does plenty of people, was not that big a deal for me. Others, good luck. I do enjoy finding out I am wrong, that means I learned something today, and it was not a waste. If the oem set the bike up for 32:1, it is not to screw you, all the parts in the carb, and the jetting baseline is wrapped around 32:1. Keep it simple. Here is where Okie lives(The Boss), read and enjoy, http://www.dirtrider.net/forums3/fo...1&pp=25&sort=lastpost&order=desc&daysprune=-1

 

[sr5bidder]

I have a rm125 that ran fine on the top end of the rpm range and had nothing down low..I DID a compression check and it was 90psi...tore it down and found a badly worn piston...
what you have posted is the experts said this and that was fine, but you did not say the experts said the compression was at xxx or the experts tore down and inspected the kips

I try to stay away from shops and do my own repairs, its sloww going at times but I have rebuilt 5 bikes in the last 2 years and chased carbs, tweaking and adjusting for hours on end and alot of times it was something else.

these bikes perform reasonable well at factory settings and properly jetting them makes them perform extreemly well so all I'm saying is if the carb clean, jetting is close and settings are correct, I would take a look at other areas reeds, kips system, cleaning and repacking the exhuast (yuk)

Have you tryed changing the heat range on the plug yet?

 

[NCFRC]

Thanks for the support mate It's good to know that I have you guys out there.
I going to aviod messing around with the oil mix I want to stay at 40-1 I'm going to check the float level a few people have said about this I just need to know how to check it for my self as so call pro's have said it right but I don't know how they checked it.Jono

Keeping your base line consistent is probably the most important thing . The other would be to keep good notes on what a particular change did to the bike and only make one change at a time . I've fallen victum to multiple changes , lets try that , and even if it did help you'll never know what actually fixed it.
Sometimes unless you find the right person , a dealer only knows the text book answer and doesn't have any real world experience.

 

[jonooffler]

Well the last setting works with a bit of a stutter but it's much better than it was it's now 38 pilot 40-1 mix and 3 rd clip I have just placed an order for a 35 pilot which I'm going to try just in case but I do feel that It's going the right way now.
Just before any one says the 35 is way to small the UK spec bike should have had a 38 fitted as standard.
Jono

 

[sr5bidder]

Jono is this an oil injected model 200sr?

I hate that the site no longer contains the "bikes" under the users name!! it leaves so much in the air when trying to help

 

[NCFRC]

That's another arguement for not comparing bikes , none are the same !
I've got a totally different combination , the bike fires up on the first kick almost
every time , runs 95% perfect and I'm very particular. A nice med/dark plug with very good low end torque. :cool:


05 / 220R
06 / 200H
Maxima Lubes
Lucas products
Prolong ETP

 

[sr5bidder]

must be the "my son's monster kdx" that "runs 95% perfect and I'm very particular A nice med/dark plug with very good low end torque"

look familiar?
I couldn't wait untill the weekend so I mixed up a fresh batch of 50:1 fuel.

First impression of a quick few mile ride is that it smartened it up quite a bit , not perfect but alot better than 40:1 .

from your low end sputter thread

as you said if there based off knowledge / experience or just bull ****.

alot of bull **** can be sorted by memory of what had been said previously

 

[NCFRC]

This thread is for more positive suggestions and if you'd paid attention we're talking about a 220 here not a 200 .

Thanks for your input anyway :bang:

 

[liven07]

If you were having problems with your kips your top end power would be lacking and your bike should run just fine with stock fuel/oil mix and jetting. If you are sure your carb is clean and the right jets, you should test the compression. If that is all good there is a very good chance it could be your reed valves, I would be willing to bet the bike is basically running off the power valve(high end), with the reed valve(low end) barely working . If there are mods on the the bike you might want to check those out and make sure there used correctly.

 

[Kaw4me]

According to Jeff Frederete this a very normal running characteristic of a stock porting 220 . Not that aftermarket porting would guarantee a fix.

I'm sure this was posted earlier in the thread but it's good to finalize things on a more positive note. :nod:

 

[Kaw4me]

I installed the 6mm slide today.

Man , what a difference ! :cool:

I didn't realize how much the stutter " rich " was effecting the
bottom end as now with just a quick blip of the throttle she'll
pick the front end.

I only had time for a short ride but this is deffinitly a major step in
the right dirrection. :nod: :nod: