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Discussion Starter #1
Long story ... I rebuilt my carburetors, bought the big kit. The kit had all the rubber diaphragms, jets, floats - float needles and mixture screws. Tore them down, soaked them, cleaned them, put them all back together and got them on the bike. The bike ran very sluggish on take off, the throttle was very flat at low RPMs. I figured out that I had my jets reversed, so I took the Jets back out and replaced them correctly. Now I have the opposite problem. It takes off fine, but the throttle has a bad flat spot at high RPMs. It doesn't sputter or miss it just loses power at high throttle.

Could this be the mixture screw, which I don't know much about?

Any tips from all you CXers would be greatly appreciated ... Thanks
 

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Discussion Starter #4
it has the original big air box under the set with a fairly new filter in lt ... the only difference is the little air-scoop cap rotted to pieces and came completely apart. i had no choice but to cut it off.

so the top of the airbox is pretty open right now
 

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As Phreak said, put the original jets, floats, needles and seats, and mixture screws back in. Those replacements that come in those kits are garbage.
 

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Your air filter likely isn't an issue, missing snorkel or not. Aftermarket pod filters can be though.

Just to be sure - the larger jet fits into the brass emulsion tube and the smaller screws directly into the carb body.
 

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Discussion Starter #7
oh man ... that sucks ... i did keep all the old brass but one of the old rubber diaphragms had holes in it
 

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If it's ####ed it's ####ed and can't be used anyway.

With the air cut valve diaphragms the important thing is that the brass knobs are the same. If so, they should be good to go.
 

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One question do rule out the obvious ... when you say "flat spot at very high rpms", at what rpm's do you feel the flat spot. 5k? 6k? red line?
 
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Discussion Starter #13
i was at about 6 or 7k ... but its all fixed now ... i just did what CXPHREAK said to do, and BOOM all fixed ... did it last night
 

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Discussion Starter #14
It's crazy ... the parts in the new kit it all looked exactly the same as the old parts that came out of the carburetors. The Jets even had the same numbers on them. The only difference that I could tell was the old parts we're heavier.

The brass Parts in the new kit were a very light yellow ... Like maybe they had some alloy mixed in.

but anyway ... thanks yall ... this is the best its ran since iv had iit
 

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'84 CX650E that is evolving into a GL500
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Here's an example of why so many of us keep saying not to use those shiny new parts that come in the kits are junk. There have been reports of jets that were not the sizes that were stamped on them, emulsion tubes with the wrong number & sizes of holes and float needles that were the wrong length too.
Pic below from Randakk's (link above), courtesy of Mike Nixon. When 2 guys like that tell you something you should probably listen.
Aftermarket Float Valve
 
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