CC, that second sweet spot...again

Questions and Answers about the best carb and Head mods available for the KDX.
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bradf
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Post by bradf »

I got to ride today, first day on the new DFIII's and experimenting with the 2nd SS. SS is exactly at 2 1/2 out. CC, previously I stated I "thought" I had pinging on decel. I did not. You were right. What I heard was a "rich crackle" during off throttle in the pipe if that makes sense. I had the carb off a while back to change the pilot to a 42 (shoulda left it alone) and my gorilla hands pressed the float up too far creating a very high float level. When I changed back to the 40 I noticed what happened. Finding the 2nd SS this time was easy. Anyways, the bike easily started out in 3rd gear, 4th was OK but had to slip the clutch a tad. 3rd and 4th roll-ons are so smooth from almost idle RPM all the way through. Bike doesn't even need first or second gear anymore. Everything is perfect. The package I have now pure fun. Anybody reading this (newbies) do yourself a favor and send your carb in to RB Designs now, don't wait, get up and take it off right now, go, while the weather is crappy, ship it in with your cashiers check for $165 to Ron. BUT WAIT, be smart and spend the extra $20 for the adjuster screw. I didn't do this and wish I would have. The air screw actually is a great tuning tool now.
'04 220 w/'01 KX250 USD forks, '02 RM125 Showa shock, Rekluse EXP 3.0, LHRB & all RB'd
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canyncarvr
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Post by canyncarvr »

Does your bike pull harder in those higher gears with the air screw further out than it did?

re: Bike doesn't even need first or second gear anymore.

Part of that is Ron's modification part of it is the reed valve. At least that's my point of view from having the two done at different times.

Ron will still send you an air screw! It's not like you had your chance and that was it! ;) Have some more fun! Spend more money!!

Good to hear you like the setup.

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bradf
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Post by bradf »

CC, yes the bike pulls harder, but smoother as well all the way to the top of the RPM. It seems like the power curve is linear rather than having a quick rising peak or immediate hard hit. Idle at 2 1/2 out is perfect. Plug check was perfect. I know the AS is out of the circuit at above 1/4 throttle so I played in the 0 - 1/4 range throttling up steep hill sides. The old decel crackle is gone, so is the quick jerk on roll on. 4th gear wheelies from moving very slow are easy and very controllable. I am not a wheelie expert, but now a roll on from idle brings it up. I am ordering my AS Monday morning. [/u]
'04 220 w/'01 KX250 USD forks, '02 RM125 Showa shock, Rekluse EXP 3.0, LHRB & all RB'd
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canyncarvr
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Post by canyncarvr »

Good deal!!

I can count on one hand the number of RB-mod riders that have bothered looking for it. Well...the number of them that have said anything about finding it anyway. Their loss.

re: 'I know the AS is out of the circuit at above 1/4 throttle..'

But...it's not. Not with the pilot circuit modified as it is. Take it back down to 1 1/4 or so. You will find that you still have good 'pilot circuit' response..but you don't have the pull in upper throttle positions you do at 2 1/2.

re: '..very controllable'

Yup! Isn't that cool? :grin:

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bradf
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Post by bradf »

CC, I did have it at 1 1/4 for a very short time. That's where I started dead cold or where the "normal" perfect idle AS adjustment was. Bike ran good, idled good, and I will cold start there as it may not run too well stone cold at the SS. I think you mentioned that somewhere else. So how far into the throttle do you think the AS has an affect? I know it is up to 1/4 cuz even with my very limited 2 smoke experience I can feel it. Making the mistake of mishandling the carb, screwing up the float, really helped me in learning the sounds of the bike. I had never heard a rich crackle before. Ritz Cracker, but not a rich crackle. You know, once the 2nd SS is found it is like a whole new, smooooth motor. When I hit it I was thinking to myself...no more crackle...so much pull...can't see over the front fender!!
'04 220 w/'01 KX250 USD forks, '02 RM125 Showa shock, Rekluse EXP 3.0, LHRB & all RB'd
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bradf
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Post by bradf »

update: I received my finger adjustable kool knurled knob end AS from Ron yesterday. So of course I had to go ride. The 2nd SS on the RB modded PWK is definitely a fine tune find. At 40 degrees the 2nd SS was exactly 2 7/16 out. Yesterday it was 50-55 degrees and the AS needed to be 2 1/2 out. There was a slight rich crackle on decel at the richer setting. In short, the 2nd SS is most definitely there and as CC says it is a very finite location. 1/8 turns are too big to find this.
Last edited by bradf on 02:12 pm Feb 03 2005, edited 1 time in total.
'04 220 w/'01 KX250 USD forks, '02 RM125 Showa shock, Rekluse EXP 3.0, LHRB & all RB'd
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canyncarvr
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Post by canyncarvr »

You got it!!

Great!!!

Yep...1/16 certainly matters. Isn't it kind'a funny that being a whole 1/8 off can turn the bike into a relative pig, 'eh?

Just shows to go 'ya....jetting matters!!

YeeHAw!!

This stuff is fun!!!

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