02 426 troubles?

8 replies to this topic
  • motobeck

Posted April 26, 2006 - 09:35 AM


I hope someone out there can help me with this one. I recently installed the Hot Cams exhaust cam in my 426. Bike fired right up and ran like a champ. However, once the bike is up to op temp, I can not get it to idle and it is extremely rich (plug is black and sooty). It either idles very high or stalls. I've tried going leaner on both the pilot and main with no luck. I have rechecked the timing and valve clearances several times and everything seems to be spot on. One other notable item, once the bike is warm, it WILL NOT start until the hot start is pulled, then it fires up with one easy kick. Is it possible that one of the slow air circuits being plugged or dirty could be causing this? I'm at a loss here, any imputes would be greatly appreciated.

  • Florida_426

Posted April 26, 2006 - 12:20 PM


Past history says clean the carburetor thoroughly. Most of us have had this problem once, at least. The FCR is reallly sensitive to dirt and grime in the jetting circuits.


  • 642MX

Posted April 26, 2006 - 07:16 PM


I agree, start by cleaning the carb and put the stock jets back in too.

  • motobeck

Posted April 27, 2006 - 09:56 AM


Thanks. I've got a new top end to put in, so I'll do the carb while it's apart. :crazy:

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  • shanedut

Posted April 27, 2006 - 07:41 PM


Ok on one note if the bike is warm use the hot start to start the bike. Thats what its for. If it wont idle right like others said clean the carb. Another thing you can look for is sometimes people get too unscrewing the idle screw too far and it will come un-hooked. Take the black cover off of the side and look at it too make sure the linkage is connected.

  • racinteach

Posted April 27, 2006 - 10:26 PM


same issue..myidle rose pretty good then all of a sudden skyrocketed....like when a 2 stroke runs out of gas...mine has the cam setup...but sounds like it will run for a bit then stops abruptly...still think the carb?

  • motobeck

Posted April 28, 2006 - 04:22 AM


[quote name='shanedut']Ok on one note if the bike is warm use the hot start to start the bike.

I only mention this because before my problems started, I only had to use the hot start in the event of a crash or stall. Now, I have to use it EVERY time I start the bike while it is warm?

  • tom nolan

Posted April 28, 2006 - 06:56 AM


If you have to use the hot start button each time you attempt to start your bike after it's warmed, than it's running too rich. I might be your float sticking or the float valve in the carb. Do you have any fuel running out of your vent tubes?

  • motobeck

Posted April 28, 2006 - 09:46 AM


I have not noticed any fuel running out. It is running extremely rich even after going leaner on the pilot and main jet 40/168. Also, the last ime I rode it, I went thru a tank of fuel about twice as fast as normal. :crazy:

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