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I too have an 810 kit in my 650 with VM24 carbs. It runs perfect with them. It sounds like your trying to say the engine hunts on steady throttle. If so raise the needle up by moving the clip down one notch.

baldy110 wrote: I too have an 810 kit in my 650 with VM24 carbs. It runs perfect with them. It sounds like your trying to say the engine hunts on steady throttle. If so raise the needle up by moving the clip down one notch.

I understand, yes, it only happens in a small "window", under normal driving and under 100kmh / 62mih I haven`t notice it, just when I goes up in high speed or deep hill in combination with some good speed...

If it were needle setting I would think it would occur regardless of how fast or slow you opened the throttle. OP said if he whacks it open it doesn't occur. It only occurs if he opens slowly.

How quick/slow I open the throttle have no impact on the issue.

It’s the throotle posistion compare to the actual RPM, when you tryto have steady RPM in the 6-7 range.

If you have the stock air box, i would give it a try. IMO i don´t like pot filters. Looks cool but made a lot of probs.

Scirocco wrote: If you have the stock air box, i would give it a try. IMO i don´t like pot filters. Looks cool but made a lot of probs.

Need to purchase one then…

I will check up the advancer and will then have much time to test it out during the weekend.

What is the symptoms of to low needle posistion?

Hi Gordone, Im still unclear about your symptoms. There seems to be some contradicting posts. I understand that English is not your first language but if you type into google translate in your native tongue and then cut and paste we may have a better understanding or the issue and be able to give a more definitive direction.
We may be missing something in translation?.

Warren3200gt wrote: Hi Gordone, Im still unclear about your symptoms. There seems to be some contradicting posts. I understand that English is not your first language but if you type into google translate in your native tongue and then cut and paste we may have a better understanding or the issue and be able to give a more definitive direction.
We may be missing something in translation?.

Do you have something spesific who are not clear?

I will try to explain another way

1. I have not noticed the issue when I accelerate.
2. I have only notice it when I try to keep steady RPM in approx. 6-7k RPM range.
3. I have a understand the issue in 6-7kRPM range only is presented when I have approx. around 50% throttle.
4. If I have 6-7k RPM and around 50% and the issue is present, and I freeze the throttle for a while the issue is there whole time… if I try to increase the throttle slowly the RPM start to pickup and then the issue disapear.
5. The problem has not been notified during acceleration.
6. When the issue is present in 6-7k RPM range and I accelerate to 9kRPM example, I have not tried to freeze the RPM at 9 to see if the problem comes back there also, but I don`t think so... will test more...

Under normal driving between 0-100km/h I don`t “see” the issue, only when I go in higher speed or combine with deep hill…

Between 0-100km/h is not often I need to use the throttle more then 50% in any gear…

So in city driving etc.. the issue is never seen.
My understanding the issue is present when I have high load and high RPM.

I will test more in the weekend, will have a long drive then…

Sort of sounds like your bike is jetted fine for power, for acceleration, but you do not like how it seems rich when held at certain throttle openings at steady state. This is totally normal for a carburetor. I always jet for power, for acceleration, so it pulls hardest through the rev range, and this same jet setting will then be rich for steady state riding, and there is no easy way around that, well there is, it's EFI. Carburetors have no good load sensing capabilities and they can't change fuel flow to adapt to different power settings. In theory the vacuum slide types are better for this, but it's been my experience that they fall short of this task. So, either jet for partial acceleration and accept that under higher loads the motor will be lean, but run smoother, or jet for hard acceleration and accept that it will be rich and not run so cleanly at part power settings.

DGA wrote: Sort of sounds like your bike is jetted fine for power, for acceleration, but you do not like how it seems rich when held at certain throttle openings at steady state. This is totally normal for a carburetor. I always jet for power, for acceleration, so it pulls hardest through the rev range, and this same jet setting will then be rich for steady state riding, and there is no easy way around that, well there is, it's EFI. Carburetors have no good load sensing capabilities and they can't change fuel flow to adapt to different power settings. In theory the vacuum slide types are better for this, but it's been my experience that they fall short of this task. So, either jet for partial acceleration and accept that under higher loads the motor will be lean, but run smoother, or jet for hard acceleration and accept that it will be rich and not run so cleanly at part power settings.

Thank you for the information, the bike is running fine, just a metter off make it perfect.

I`m not running constant in that speed we talking about either, so no big problem...

More that… is it possible to make it even better….

No, I don't believe you will get 'perfect' with carburetors. We are all so used to EFI in cars and newer bikes, younger people often have no idea what a carb is these days. If you want perfect, consider going down the rabbit hole of EFI, I am doing just that right now with a Microsquirt system on a GPZ500R.

Really, yes you can get carbs to run perfect at all speeds and rpm ranges. Been tuning carbs for over 40 years and I seem to dial them in perfectly. You just need to know what throttle setting effects which carb circuit then tune each circuit till it's perfect. EFI is not the magic bullet.
If the engine surges under neutral throttle which sounds like your problem then it's lean on the needle. By neutral throttle I mean your not accelerating or slowing down but keeping the throttle steady.