RB vs FRP carb / head mods

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iswenson
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RB vs FRP carb / head mods

Post by iswenson » 08:40 am May 22 2014

I see that both RB designs and FRP (Freddite) have the carb + head mods on their websites. Is there a difference between the two.

FRP: 148 bucks total

65 - head work
83 - carb work

RB designs: 218 bucks total

50 - head work
168 - carb work


I hear a lot about the RB work ( a whole section of this forum is dedicated) but I do not hear much about the FRP work. Can anyone fill me in as I am planning on doing this, and I am intrigued by the large cost diff.

Ian

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Julien D
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Re: RB vs FRP carb / head mods

Post by Julien D » 09:26 am May 22 2014

You can look at the details on both sites and see what is included. FRP bores the carb throat and swaps jets. RB bores, adds divider plate, reworks low speed circuit, modifies jet block, modifies slide, new needle, new jets.
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iswenson
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Re: RB vs FRP carb / head mods

Post by iswenson » 09:40 am May 22 2014

OK. Any idea what or how much better the Rob carb works, is it worth it

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fuzzy
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Re: RB vs FRP carb / head mods

Post by fuzzy » 09:51 am May 22 2014

Yes, for a 200 I would never even bother with the FRP mod. For at 220 at least youre getting a 36mm bore job. The RB carbs pull off idle like no other. Can't speak to his head work
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iswenson
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Re: RB vs FRP carb / head mods

Post by iswenson » 10:14 am May 22 2014

Cool sounds like Rob is the way to go. Both are actually pretty cheap. Gotta love 2 strokes

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Re: RB vs FRP carb / head mods

Post by KarlP » 12:10 pm May 22 2014

I don't know what FRP does to heads. I'm sure it is an improvement, the 220 is pretty de-tuned by design.

I do know the RBD head work was great on my 220. It made a huge difference.
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Re: RB vs FRP carb / head mods

Post by Julien D » 01:18 pm May 22 2014

The FRP head service is milling only, AFAIK. RB mills and reworks the squish band.
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iswenson
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Re: RB vs FRP carb / head mods

Post by iswenson » 02:09 pm May 22 2014

Awesome. Really sounds like a 'must-do'. Plus I gotta check if the '04 220r I just bought has the original piston or not....so the head is coming off anyways.

Speaking of which...can I check if the piston is the original or an aftermarket w/o pulling the jug? Any pictures showing stock vs. forged (wiseco) would be helpful

Ian

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Re: RB vs FRP carb / head mods

Post by KarlP » 03:00 pm May 22 2014

You'll have to search around on here. I know I've seen such pictures of the piston tops.
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Re: RB vs FRP carb / head mods

Post by Joshmcmillan » 09:05 pm May 22 2014

iswenson wrote:Awesome. Really sounds like a 'must-do'. Plus I gotta check if the '04 220r I just bought has the original piston or not....so the head is coming off anyways.

Speaking of which...can I check if the piston is the original or an aftermarket w/o pulling the jug? Any pictures showing stock vs. forged (wiseco) would be helpful

Ian
You can take the expansion chamber (exhaust) off, and shine a flash light in the end and have a look at the piston. You may be able to see enough to tell if it's oem or aftermarket that way, and if you can't, well you would have had to take the exhaust off anyway.

Short of that, you do need to take the jug off. Don't take the top cylinder head off or you have to replace the head gasket. So leave the head on, disconnect all coolant lines, top engine mounts, exhaust, carby etc... undo the 4 jug bolts and pop it off.
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RB vs FRP carb / head mods

Post by pumpguy » 09:47 am May 23 2014

You might try using a mirror and light to look at the piston top through the spark plug hole. Typically Wiseco pistons will have a multi-letter/number marking on the top of the piston dome, while the Kawi piston will only have a letter.

If there's not too much carbon on the piston dome, you might be able to see the markings without having to take anything more apart.

Good luck.

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RB vs FRP carb / head mods

Post by iswenson » 10:12 am May 23 2014

thanks guys. I was planning on taking the head off anyways to do the RB head mod, so I was thinking about NOT taking the jug off if I knew it was a wiseco.

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RB vs FRP carb / head mods

Post by scheckaet » 11:30 am May 23 2014

I thought there was some marking on top of the piston as well as under?

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Re: RB vs FRP carb / head mods

Post by GOT WOODS? » 10:32 pm May 23 2014

I just put a Wiseco in my 220 and interestingly while it had the "dot matrix" number etchings on the crown, the "W" on the bottom that I had seen in several pictures on here was not there. So if the piston top is carboned up you may not see the numbers on it and if you are looking for the W on the bottom you might not see that either. The one main identifier that I have seen in pictures to identify the stock piston looks to be the "cross hatch" pattern stamped on both sides by the piston pin.

On another note, anyone else ever use acetone to remove carbon off the head and piston? I had a can laying around and I figured "why not" and tried using it to get the carbon off. Pretty much cleaned it off almost (but not quite) instantly. Did I invent something new or am I late to the party? I never tried it before, I was impressed. Or did I just kill my bike somehow???
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2003 KDX 220:
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Turbine Core 2 silencer
Fat Bars
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