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Honda Diaphram

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After reading AP101 I realized that I installed a Honda diaphram on my dual sport. Is anybody else running this version on their street/dirt bike? If so, is it working out well?

I think my bike runs well but I don't want to destroy the motor. I have stock jetting with an OCEMN needle and o-ring mod.

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The stock needle will do more harm than the Honda diaphram.

If you don't have any bogging issues the I wouldn't worry about the AC pump.

A lot has to do with your riding style.

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if your main jet is still stock....then it is way to rich for the OCEMN needle.

I might help to know what year and model you have

DBM

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All you did with the Honda diaphram was shorten the duration of the AP squirt when you twist the throttle.

No biggie there....That in fact will make your bike snappier and more aggressive off idle when combined with the proper jetting.

What your real issue is with that EXC 4 stroke (Depending on the year) is the ridicoulously lean settings that it came with stock. Those lean settings combined with the plug in the exhuast equal lots of heat and poor performance. Excessive heat is bad. Do yourslef a favor and drop a few bucks on the JD jetting kit. You will be glad you did!

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It is a 2007 525 engine with:

178 main

42 leak (?)

85 pilot (?)

OCEMN needle in the 3rd position, o-ring and Honda diaphram.

In Dave's AP101 he mentions that the Honda diaphram is too lean for light throttle openings commonly used on the street. It will burn up the motor. For the dirt it's works great where there is tire slippage, I think.

If this has been covered adnausium, please disregard, but if the bike is lean from the factory, why wouldn't changing to a slimmer needle be the same as installing a larger jet?

OK, I do still have a slight bog occassionally, but I just bought this bike so I am still working on getting the combination right.

Thanks for the input. :)

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you should be close to these specs

158 or 160 main

42 pilot (I use a 40 in Fla)

# 60 leak jet

2 turns fuel screw

OCEMN (3)

DBM

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I agree with DBM approx jets. Also if afraid of the Honda diaph then get a Yam, I think they make 3 and at least one of them is between the Honda and KTm with about a 1.5-2sec squirt, split the difference.

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In Dave's AP101 he mentions that the Honda diaphram is too lean for light throttle openings commonly used on the street. It will burn up the motor. For the dirt it's works great where there is tire slippage, I think.

:)

i was going to say the same thing from what i've read for dual sport use you need the longer squirt. your just cant ride aggresive enough on the street and end up lean off the bottom.

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