RB carb mod
- canyncarvr
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I did a search on this board for 'throttle response'.
I found a number of posts with exact how-to on adjusting the pilot circuit.
One thread pretty close to the top of the list was authored by some guy with the nick 'awoodman'.
That post covers modified and unmodified carbs.
That post covers the SSS, also.
I found a number of posts with exact how-to on adjusting the pilot circuit.
One thread pretty close to the top of the list was authored by some guy with the nick 'awoodman'.
That post covers modified and unmodified carbs.
That post covers the SSS, also.
Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis
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- canyncarvr
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***stringburner wrote:Look to the subject line and all will become clear (RB Carb Mod).canyncarvr wrote:I don't know what that means.I see most people raving about the mod on their 220's, but not alot about the 200's. I was thinking the head mod gave better results on the 200 than the carb. mod. Not so?
What 'the mod' on the 220, but not the 200?
I was referencing the subject in context, then I mused that the head modification seemed to get more praise than the carburetor modification, on the kdx 200. I figured boring the 220 carb would give better results because its bore is smaller than on the 200's carb, and the 220 has more displacement, and is basically starved for flow at upper rpm's. Clear? I understand it's not all about the boring, but adjustability too.
Your post had no subject. ;)
Got it. My apologies. I rarely read the subject with the thread. A personal foibile (one of many).
My earlier statements still fit.
I don't want to let it sit that the head modification is preferable to the carb modification for the 200. It is not. Maybe it should be, seeing as they cost the same.
Just kidding! Simply adding more confusion to what is already a thread that has exceeded my escape velocity.
****
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- stringburner
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I think that's the point I was getting at actually. Which, if you were only going to do one, would be recommended. I'll probably do both, but likely not the air stryker carb. That is a little high (to me). I just want it to run clean and not feel like it's running against itself. I couldn't get my bike to wheelie whatsoever. Proper jetting would probably help alot. I'm around the same elevation as Inda I think (600~ish), so I may try his jetting specs. Anyway, sorry for hijacking the thread.
- canyncarvr
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If you're only doing one, IMO the carb modification would be it, yes.
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- awoodman
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I am trying to tune the air screw while it is around 50 degrees F outside. The jets are meant for like 70+, so how big of a difference is +/-30 degrees? And also, I have stock reeds. Will this make a big difference on the carb mod performance?
Last edited by awoodman on 07:32 pm Dec 19 2006, edited 1 time in total.
- canyncarvr
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Regardless of the temp, the air screw will be adjusted in the same way. Probably won't end up in the same place, but you do it the same way.
I have not run a modified carb with OEM reeds. I would be surprised to find the reeds have anything to do this discussion. I mean, preventing the carb from performing the way it does with aftermarket reeds or reed cages.
They (OEM reeds) will make a difference in performance (less than other choices), certainly. The carb will still function fine.
I'm assuming stock reeds in good condition. Trying to jet a bike with any reeds that are NOT in good condition is a huge waste of time. You will never get it 'right'.
I have not run a modified carb with OEM reeds. I would be surprised to find the reeds have anything to do this discussion. I mean, preventing the carb from performing the way it does with aftermarket reeds or reed cages.
They (OEM reeds) will make a difference in performance (less than other choices), certainly. The carb will still function fine.
I'm assuming stock reeds in good condition. Trying to jet a bike with any reeds that are NOT in good condition is a huge waste of time. You will never get it 'right'.
Consider the source
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- canyncarvr
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Sorry. I assumed that to be understood.
Re: '..will i need to change the jetting for these colder temps?'
Yes.
If you want it to be 'right', you do.
I change my air screw (effectively changing jetting) several times a ride, more often in colder weather. That's due to there likely being a wider range of temps with the sun out during these shorter days of the year.
Don't misunderstand. It is NOT necessary to dink with your carb 20 minutes for every 15 minutes of riding. My bike isn't jetted 'correctly' MOST of the time for that very reason. Being 'right on' by the numbers, by procedure and jetting method is something to yak-yak about, but certainly isn't required to have fun riding!!
A few motos in a covered arena over the timespan of a single day ain't the same a'tall as starting a ride without the sun in the 20ºs, and ending up riding in the sun in the 50ºs.
Don't give yourself a hernia over it. Understand the basics, change things as often as suits 'ya!
This is supposed to be FUN!!
Re: '..will i need to change the jetting for these colder temps?'
Yes.
If you want it to be 'right', you do.
I change my air screw (effectively changing jetting) several times a ride, more often in colder weather. That's due to there likely being a wider range of temps with the sun out during these shorter days of the year.
Don't misunderstand. It is NOT necessary to dink with your carb 20 minutes for every 15 minutes of riding. My bike isn't jetted 'correctly' MOST of the time for that very reason. Being 'right on' by the numbers, by procedure and jetting method is something to yak-yak about, but certainly isn't required to have fun riding!!
A few motos in a covered arena over the timespan of a single day ain't the same a'tall as starting a ride without the sun in the 20ºs, and ending up riding in the sun in the 50ºs.
Don't give yourself a hernia over it. Understand the basics, change things as often as suits 'ya!
This is supposed to be FUN!!
Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis
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- awoodman
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Are you at low rpm (around idle) and snapping the throttle wide open instantly? My bike bogs under those circumstances, no matter what jetting I use.awoodman wrote:you mean that when I have it at 0 throttle and i go WOT right off the bat, it shouldn't bog at all? because it does badly. Theres no whay to tell which way to turn the airscrew?
Try rolling on the throttle for a short moment until the revs build just a little, then you should be able to snap the throttle wide open without a bog. If you want to launch fast, rev the bike with the clutch in and feather the clutch out while adding throttle.
What jetting are you using? Try raising your needle by 1 clip. I went from CEK-3 to CEK-4 and it cured a bog I was developing when the temps dropped. Getting your jetting close is not too hard once you get the hang of it. Like CC said, it does not need to be perfect to have a blast.
Good luck!
Tony
- canyncarvr
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Questions are fine.
Re: 'Are you at low rpm (around idle) and snapping the throttle wide open instantly?'
..and this:
Re: 'Even with colder temps, i shouldnt need to change the jets..'
sounds real familiar...within the past week?
What grump said is right.
Even with colder temps...you SHOULD rejet...if it WAS jetted properly for 20-30º higher.
Re: 'Are you at low rpm (around idle) and snapping the throttle wide open instantly?'
..and this:
Re: 'Even with colder temps, i shouldnt need to change the jets..'
sounds real familiar...within the past week?
What grump said is right.
Even with colder temps...you SHOULD rejet...if it WAS jetted properly for 20-30º higher.
Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis
bike profile: !clicky!