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Accelerator Pump Tuning Tutorial: Where is it?

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Before you flame me I have searched and searched and searched the jetting forum....

Wheres this tutorial at?

I ordered the replacement AP diaphragm and link rod only to find out that I ordered the 06' version.... aka, not the updated 08' version with stiffer spring.....That being said, should I return my 06' package and buy the 08' part # 16021MENA01 or keep the 06' and buy the merge spring? Aka, are the merge spring and 08' pump identical, or is the merge stiffer?

I plan to finally kick this carburator issue in the butt this week! :smirk:

Edited by macklikesbikes

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Before you flame me I have searched and searched and searched the jetting forum....

Wheres this tutorial at?

I ordered the replacement AP diaphragm and link rod only to find out that I ordered the damn 06' version.... aka, not the updated 08' version with stiffer spring.....That being said, should I return my 06' package and buy the 08' part # 16021MENA01 or keep the 06' and buy the merge spring? Aka, are the merge spring and 08' pump identical, or is the merge stiffer?

I plan to finally kick this carburator issue in the butt this week! :smirk:

The '08 pump diaphragm will not work on an '06 carb unless you remove the check ball. Stick with the '05/6 parts.

The spring that comes with the diaphragm repair kit is the diaphragm spring (in part #1 grouping), not the linkage detent spring (aka merge racing) (shown as the inner spring in part # 13 grouping) which is what you want to update the apump action. Different spring.

http://www.bikebandit.com/houseofmotorcycles/2006-honda-crf450x/o/m2273#sch413732

And yes, the diaprham spring you see in the '08 repair kit is stiffer than the '06 stock spring, but all you have to do is 'strech' the stock '06 spring 1" to get the same results.

There are several dozen videos on utube on adjusting the apmup.

- leak jet size (50 is what you want) determines fuel quantity, and squirt duration (1.3 seconds is what you are shooting for)

- linkage detent return spring puts pump and throttle in sync, with a slight cushion to prevent binding (oring kind of does the same thing, but poorly, and not for long until it breaks)

- linkage adjustment screw determines when the squirt begins. You want it to begin as soon as possible, without hitting the slide. Generally you can adjust the screw to put the linkage 1mm spaced from the throttle linkage.

This page on youtube has lots of videos

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Awesome Krannie, I almost went and reordered the newer kit.

By 1" do you mean pull it 1" inch then let it go back or get the total spring length an entire 1" longer?

I also just put in a #35 leak, do you recomend going to a #50?

Also: When I run this test will the gas in the float boal be enough or will i have to hook the tank up?

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Awesome Krannie, I almost went and reordered the newer kit.

By 1" do you mean pull it 1" inch then let it go back or get the total spring length an entire 1" longer?

I also just put in a #35 leak, do you recomend going to a #50?

Also: When I run this test will the gas in the float boal be enough or will i have to hook the tank up?

Make it longer

35 will probably be fine.

Float bowl should be enough, but only for about 10 squirts.

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1 More question then shes goin back together....

My link rod has a little play in the ball socket, is that OK or normal?

Should I replace the black plastic link arm?

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1 More question then shes goin back together....

My link rod has a little play in the ball socket, is that OK or normal?

Should I replace the black plastic link arm?

I'm not sure about that one. I don't see how having slack is good........

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1 More question then shes goin back together....

My link rod has a little play in the ball socket, is that OK or normal?

Should I replace the black plastic link arm?

When I dialed mine in last year, I remember that ball being very tight in that spot. I could not even pop it out without feeling like I was going to break it, so I didnt. Just my 2 cents on what I remember from over a years worth of tinkering ago.

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