I need jetting spes for my fcr keihin on my vor 530cc so it runs well

Carburetor jet plugged or out of adjustment.
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THe accelerator pump is a squirt gun diaphram type of pump. To test it you need to be able to view the jets and actuate the throttle cable.

I would first make sure the power valve is decarboned and moves smoothly. Jetting is trial and error as so many things can affect the mix. Temp. humidity, gas quality, oil ratio etc. Tht being said you can make small changes and keeping a log with results. First write down baseline settings. Include main jet and pilot jet numbers found stamped on the jets and needle number. You don't say where it is you are trying to get power. 125s have poor bottom mid power, it is all on top for racing. Don't change and race or you may keep going when you should stop and melt something. Try to test at the altitude where you will race and read the plug often, cleaning or changing the plug between tests. Be alert for the surging feel of lean mix with racing idle do not let this continue. Remember 0 to 1/4 throttle, pilot and needle base width. 1/4 to 1/2 throttle controlled by needle mid taper. 1/2 to 3/4 throttle needle tip and main. 3/4 to full is the main jet. Find out the stock settings and make sure to start near there. I don't know about a spes pipe but pro circuit has charts for jetting and maybe a support line. I really feel you will get more from a clean powervalve, repack the silencer, clean airfilter and maybe v-force reed. Gearing can offer some options. I just read about a James Dean jet kit for cr250 that puts more power in the low mid. I might try that for my bike. Good luck, just remeber " too lean, too long- too bad"

if the airbox and intake boots are the same size then it should work, but your bike will run rich, you will need to re jet it.

best thing go to a dealership in your area, they will advise you and the cost of a jet is very small.

verify spark - fuel - air

No! It will not work on your bike! Save yourself some major grief by sending it to me! :thumbsup: :lol: But seriously folks... it will work great once whatever jetting changes that may be required are done. I'm thinking you'll have to do some throttle cable rigging and possibly adapters for the air boot and/or intake manifold. I have no experience with this conversion so I'm just assuming. Taking the carbs off for measurements would answer all those questions. Certainly a doable project and a mass improvement over the vacuum slide Mikuni!! I have every intention of doing a project like this once I'm back in my home state of Michigan. Just in my initial thought process I believe I would pick the 39mm carb over the 41mm carb. My primary reason would be to maintain and/or improve low end. There will already be a marked increase in top end even going to the smaller bore due to the superior flow design of the FCR carb. Good luck in your project.... I'm jealous! If you ever think of not doing the project for whatever reason I'd be interested in buying your carb