RB Carb Mod

[RBD]

Here is a new performance enhancer for the gasgas 250 and 300. This is a complete carb mod to help with some of the problems that some people experience with low end throttle response and want to get the best performance out of their bike. I have been working on this mod for the past year now and field testing has gone extremely well

This is not just another jet kit; it's a complete carb make-over that helps with the over-all tune-ability for all situations from the very bottom-end through the top-end.

This mod is not meant to compete with other jetting kits out there, its taking carburetor tuning another step higher.

Your stock carb is bored to 39 mm (a little better top-end) and my proven divider plate is installed (helps with low to mid range throttle response and tune-ability). The low speed circuitry is modified along with the slide, this helps bring the mixture screw into play. The mixture screw now becomes a very sensitive fine tuning tool for altitude and temperature changes.

The carb mod will come jetted very close and ready to ride, plug and play so to speak (Note! Some fine tuning maybe necessary). As this is an “Experimental” carb modification with on going research and development, your feed back will be very instrumental in the on going refinements of this product.

Thank you,
Ron

[PEB]

How much for the carb treatment?


Paul B

[RBD]

Originally Posted by PEB

How much for the carb treatment?


Paul B

More info Click Here

[Boomhauer]

All,
I was very lucky to be chosen by Ron to do some testing on this new carb mod he is talking about. I can not even begin to tell you how much a difference these carb mods made my bike run & react. Below is an e-mail that I sent Ron after the 1st test I did. Please read it. You guys should have Ron do this mod for you. Only small adjustments will be needed.

Robby
__________________________________________________ _______________
Ron,
Pardon my language but HOLY SHIT!!!!!!!!! This carb is awesome! I put the
carb on my bike Friday night. I did some research and found that the factory
jetting was suppose to be a 180 main and a 42 pilot, so just to be on the
safe side I put those jets in the test carb.

I started the bike in my garage and got the base line set for air/fuel and
the idle just to see if the bike would idle smoothly. Well it did with
minimal adjustments. I kept the needle that you put in the carb and
did not even adjust the clip position. It was set in the middle position.

So I get out to our riding area today to unload and start up the bike to get
it warm for some full throttle testing to insure the jetting was close and
safe. I did 2 full throttle pulls with a new plug in the bike. When I first
gave it the gas the front of the bike came off the ground. The throttle
response was so smooth, quick, & clean. Right away I knew this was going to
be a fun day of testing! So I got fully geared up and went out riding &
testing.

The remainder of the day I just trail rode and put the bike thru some good
tests. At one point I went up a very steep hill in 1st gear just lugging it
to the point of stalling it and then cracked the throttle just the slightest
amount and the bike jumped back to life without hesitation. I can say it was
the smoothest my bike has ever felt! I did turn the air/fuel screw back in a
bit, and like you said it only took a small amount of adjusting.

I pulled the plug out at the end of the day and it looked like it was almost
just a bit on the lean side. If it is a bit lean I would hate to see how it
reacts when it is richened up a bit more. You know more gas = a faster bike!
LOL

I think you have hit the nail on the head with the mods on this carb. My
bike has never run so,so, good! I spoke with Girard earlier and told him how
shocked I was at how well this carb did and how well my bike performed. I would highly recomend
this mod for the bikes. It really works and I will vouch for it.

I really don't want to take the carb off and give it to Girard now but I
guess I will have to! LOL Being how I was so impressed with the carb.

A very Happy Rider,
Robby

[Cruiser]

Whats the turnaround time?
Steve

[GMP]

I would love to do this, along with the head. I have to pick a week when I'm not riding. After missing a lot of rides this spring waiting for the bike, I hate to lay it up. Fortunately my bike runs very well with just good jetting, but I know there are always room for improvements, especially concerning the air screw sensitivity. I have a good performance baseline now.

A bike that could really benefit from this is my brother's Husky WR250. The Mikuni is a PIA. First we would need to find a Keihin at a good price.

[Magellan]

I was also lucky enough to do some testing of Ron's work.
My review is posted here (in Product Reviews):
http://www.gasgasrider.org/forum/showthread.php?t=1140

Next up for me is the head mod.

[jeffd]

I rode Jimmy's (aka magellan) bike over the memorial day holiday. It had one of Ron's modified carbs on it. The bike ran and carburated very, very well.

It transitioned from one circuit to another very cleanly... I am very, very picky and sensitive and like things to be totally "dialed in". I ran it up and down a logging road a couple of times and I noticed a couple of things that I didn't expect. The first is that it pulled into the mid-range very strongly and then transitioned from there into the top end strongly. I had ridden Jimmy's bike before and it used to start to sign off as you went into the top end - I previously attributed this to the pipe and port timing (I had an '01 and he has an '04). Now the bike accellerates cleanly all the way through and it is very fast. And I mean feel of a very constant acceleration in your gut fast - not burst, uncontrollable hit of power that makes people think a bike is fast when it isn't ...

I am not a big believer in "power now" devices (divider plates), etc. But I think the combination of things that Ron does all work together in an extremely efficient package.

1. I felt a stronger transition and smoother acceleration off the lower mid to the upper mid - I attribute this to the divider plate installation. But it is more linear power delivery through this transition - so it "puts it to the ground" in a very efficient way (you go fast, quickly and it does not surge or yank).
2. The bike rev'ed on top like it didn't before - I attribute this to the boring of the carb to 39mm. I was surprised at how noticable this is, I didn't expect it to be as noticable as it was. I attribute this to two things working together - the divider plate + the 39mm bore. It pulls into the top end strongly due to the divider plate and once you "get up there" - it pulls longer due to the increase in bore size.
3. The bike started very easily and this was with the old short oem kickstarter that I despise (I had a yamaha kicker on mine). I didn't really work the bottom, off-idle transition - Because on the logging road, it just "got up and went" and I was quickly mid to top... It "revs freely".

I can't comment on the ease of adjustability that this carb mod also provides. Jimmy said it was very easy to tweak in the air screw - the carb block mods that Ron makes adds sensitivity and adjustability. Jimmy also had a nifty air screw adjustment knob mounted on the carb that Ron machines up for the pwk - it makes the air screw adjustment a tool-free affair for trail side adjustment, etc. Here is a link to this little doo-dad on his website.

jeff

[Boomhauer]

Guys,
The air screw adjustment is minimal to get results. I just turned the air screw the slightest amount and got big results.

I was also lucky enough to try out Ron's newly designed needle with his carb and my carb. I can tell you that the results were great.

Being as how I am getting ready to sell my bike to buy an 07 I did not want to send Ron my carb to do the mods. Instead I told him to ship me a new slide that he cut down and his new secret weapon needle.

If you don't do all of the mods to the carb let him cut your slide and buy one of his needles. This needle really did wonders for the performance of my bike. It now has zero hesitation and the throttle response is amazing with no bogging on the bottom end or the top end. The bike just kept pulling hard.

Buy one of his needles you won't be sorry!!!!!!!

Boom

[texta]

Will this available to be shipped Internationally as I would love something like that over here in Oz.