Need O-ring mod link

I have searched here, the jetting forum, google, I can't find it Please help

tell me about slipping an o-ring under the ap linkage. Do you have a link to that?

in the conversation i had with Brian Kinney (and have posted on here several times!!!) he specifically said that the ultimate solution just may be changing the leak jet *provided the timing of the squirt was correct*.

if your squirt duration is 3-4 seconds with a 40LJ, then you obviousally need to take it out and use a 70, 80 or 90..... AND (big and) it is not so easy to do the BK mod on the newer carbs as they don't have the tab like the 01's did.

Nice, I would like to hear the feedback. Thanks.

the best solution i have found is just get your jetting right. all these little tricks only help if your jetting is wronge. if you go richer on your piolot jet you can jet out the bog.

the best solution i have found is just get your jetting right. all these little tricks only help if your jetting is wronge. if you go richer on your piolot jet you can jet out the bog.

Yes, and no. Getting the jetting right is paramount. You can overly richen the pilot circuit at the expense of idle - 1/4 throttle power and some midrange response...

That still doesn't overcome the physics of opening the throttle and the loss of engine vacuum going low enough to reduce pilot nozzle flow. It's just that if the pilot circuit is set overly rich, the a/f mixture stays in the combustible a/f ratio range longer when vacuum is lost. But then the carb is not set to the "best power" a/f ratio at the bottom end of the throttle arc, and since the pilot circuit works all the time, it affects the needle transition by also having the low-end of the needle operation too rich for "best power" as the throttle transitions to mid-range. (That was a lot of words, I hope it reads sensibly).

The FCR carb has a basic design flaw of inadequate/variable accelerator pump pressure due to aeration in the AP reservoir. The safety wire and o-ring AP mods force the AP cam to move with the AP link, raising the AP squirt pressure, purging aerated fuel quicker, and compensating somewhat for this particular design flaw. The Powerbowl, QS2, and other bowl/ap reservoir replacements attempt to deal with this design flaw - some designs being more effective than others, and some depending on how well-tuned a given carb is.

the best solution i have found is just get your jetting right. all these little tricks only help if your jetting is wronge. if you go richer on your piolot jet you can jet out the bog.
While I agree that the best solution is to properly jet your bike, I disagree that these fixes only help if your jetting is wrong. I believe these fixes make good jetting slightly better (especially the O-ring mod), but your underlying jetting problems will remain, regardless of the mods. I have also found that dependable E-starting is highly dependant on good pilot circuit jetting; that is, neither too rich nor too lean are good.

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