buzzard

While snowed in, it's time to fiddle with things. I read about these two products on this site, and decided to buy them, and install them. I have had an issue with the accelerator pump ever since I removed the carb, looked into the engine side of the carb, worked the throttle and squirted myself in the eye. Seriously, I have felt that the pump delivered too much fuel. This diaphragm has a taller metal pellet, which limits the stroke of the diaphragm. The end result is a pump stream of about .75-1.0 second, instead of the three second stream it has had. This kit from Honda includes the new diaphragm, o-ring seals, actuator rod (identical to stock one), aluminum pump cover, and a new spring. All for about $20. Then there is the new needle jet from Factory Pro (Factorypro.com), which has holes in it that the stock one doesn't. At their website, they have an amazing video of two carbs (one with, one without) showing how the stock one delivers fuel out of the needle jet in blobs, while the one with holes aerates the incoming fuel, delivering it as a mist. Again, about a $20 part. I have them installed, but have not thoroughly tested them. A couple of big donuts in the snow felt great. I have a bit of wonderment about the new aerating needle jet. Factory Pro says it will not affect jetting, yet it introduces air into the incoming fuel stream. Hmmm

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husabutt

Hi Buzzard:

I couldn't find the video for the Factory Pro needle jet. Could you possibly post the link?

Also did you consider their Husaberg jetting kit that they sell? Does the kit come with the modified needle jet? It doesn't appear to.

Thanks,

Eric

sandskipper

buzzard,

Nice write up and information. Keep the group updated on your experiments and findings on these products as they do help other members in their quest for carburetor bliss. Keep the rubber side down.

Regards,

buzzard

Go to factorypro.com, choose Carb jets emulsion tubes on the lefthand column. It will take you to a long list of produucts, drop down to HDJ High dispersal jet, on the right hand side of that row will be a "click here", click it, and the video comes up. It is impressive. I talked with the folks at Factory Pro about the jet kit, and thought it was a lot of money for what is mostly a custom needle. I'm not that far off with what I have to need a new one, though I would love to test one without buying it! The gentleman at Factory Pro said that, in his opinion, no one had the FCR figured out very well. They developed their kits with a dyno, he said. I will definitely report back with results when the Arctic conditions subside a bit.

sethro

i tryed the honda diafram that you have there on my 07 650 and it produced a bad bog(lean) when I wacked the throttle open, not enough fuel , I had to go back to stock, may or may not be the case for everyone.

Sethro

Johnf3

There are lots of variables involved in jetting. I'm the one that brought up the use of the Honda diaphram here on this forum. A short (or even disabled) AP pump doesn't work right with the stock needle. Husaberg has the long AP squirt duration to "fill in" for the very lean stock needle. Once you change to a richer needle, you can alter the AP duration.

buzzard

Johnf3, can you tell me what needle you used? I wonder if the stock needle the CRF450X uses is a good starting place. My jetting dilemma has centered around the accelerator pump. When in tight going, on and off the throttle, it gets artificially rich due to the pump. I have not had the chance to try the new mods in trail conditions yet. Blazing around the yard in a foot of snow, it feels good. Also, with this Honda diaphragm, the stroke(duration) of the pump is somewhat adjustable by turning the adj screw. With the screw backed all the way out, there is nearly zero pump action. As you turn the screw in, you increase the pumps action. With the stock diaphragm, you had adjustment- lots, or really lots of fuel. This FCR had more accelerator pump action than the Q-Jet on my old Chev 454! Well, maybe not quite. I am determined to fully understand this FCR, and to learn how to make it do what I want it to.

sethro

I did replace the needle, I have been using honda diaframs for long time with all my bikes with 41 pumpers, a good little trick, but the hussy 650 needs the fuel so back with the stock part, not that that is bad, runs like a raped ape!!!!!!!!

Seth

buzzard

I couldn't stand it any longer, I went for a snow ride today. Climbed some snow hills, roosted in rocks and ice. I do have a lean condition cracking the throttle at times. However, it runs better than ever excepting that! After some research on the internet, and at the local Honda dealer, I found that the CRF450X comes stock suited to meet EPA certification. It too has the same lean condition. Honda never quits amazing me. They make a needle that goes in the 450X if it doesn't need to meet EPA regs. Honda part # 16233-MEN671. I have one ordered. It will be here next week. I will install, and dutifully report the results. Of course, it is $20. This will be a $60 spruce up before it's done. We're getting close! As a postscript, Sorrels are not bad riding boots.

husabutt

Since your in the mood for testing................

http://www.slavensracing.com/p_nobog.htm