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5th gear BOG ,,new FCR

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I installed the FCR 39 flatside carb,,pulls great all gears except 5th

If im doing sat 50 .55 MPH 1/2 throttle and wack it to full throttle,,It BOGS out big time if I keep on full it hesitates a spit second then pulls good but seems very slow to get to higher RPM's :thumbsup: DONT know the jet sizes

this motorcycleCarbs place would not tell me (BIG Secret) I think its the main jet from what ive read,,I bought a 160 & 158 main at the local store,,

1. where is this main jet located ?

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pull the float bowl off and it is the one in the center.the needle slides into the hole the main jet screws into.there is an access bolt that is in the center of the float bowl,you can take that out to access the main jet as well.if you take the float bowl of you will be able to see all the jets in there and get the sizes off of them for more info.also sudco has a diagram of the fcr.it makes telling what jets are what much easier.

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Do you think this BOG is caused by a main jet problem,,If so should I go up or down in size :thumbsup:

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Do you think this BOG is caused by a main jet problem,,If so should I go up or down in size :ride:

You need to know all the jet sizes in your carb, without them it is all guesswork.

And if it is the main jet, it could be lean or rich, or a combination of needle and main jet.

Neil.

:thumbsup::applause::applause:

Sudco Carb diagrams here.

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A bog in only one gear tells me that maybe you are lugging it in that gear :thumbsup:

What is your final drive ratio?

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gotta know the main jet and needle thats in there.

Dont know ,, I will pull carb today,,and I felt it it all gears with very high Rpm's

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A bog in only one gear tells me that maybe you are lugging it in that gear :thumbsup:

What is your final drive ratio?

Sorry but Im new at this ,and i DO not know what this is or means

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Sorry but Im new at this ,and i DO not know what this is or means

divide the front sprocket tooth count into the rear sprocket tooth count

15 div 47 =3.13 ratio

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divide the front sprocket tooth count into the rear sprocket tooth count

15 div 47 =3.13 ratio

OK I do know what this is ,,,15/46=3.06

thx

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Your final ratio (15/46 or 3.06) is low enough that I wouldn't think you were lugging it at 55mph but I could be wrong there. Check you jets and then try what eddie recommends for it.

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The Main Jet is 160,,and it has an EMM needle,,

Im getting better not Older ,,I can take that carb out and back in 2 hrs

I ordered an EMN needle ,,,they said its in the box,,NOT

they are sending me a new one

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