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Ed_Buratti

XR650L aftermarket cam ?

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XR's Only sells a competition cam for the L. There is a guy on the xrlug yahoo group that has a WB cam installed on his L, along with pumper carb and a high compression piston. It's pumping out 52 hp. :)

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I did the White Bros cam (I think) and high comp piston and light port to head and geared it down. I was dissapointed for the money. I'm not saying it wasn't faster, just not what I was hoping for. I want to do the cam and piston to my 650R now and am afraid of the same dissapointment per $ spent so I am holding off for a while.

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Hotcams also offers a cam for this bike.

Most of the aftermarket cams offer an incease in high-rpm power by increasing duration. This lowers effective compression at low rpms, taking away significant low rpm power. Increasing the compression ratio with a piston will bring some of this lost low rpm power back. On a 650L you can increase the ratio a point or two, but there are limits to this unless you want to run race fuel (it doesn't help matters any that it's an air cooled engine). A cam with greater lift but equal duration will increase power without so much loss of low end, but since the valves must open further in the same length of time, this type of cam tends to be tough on valve train parts.

Most people replace the cam and piston at the same time, which is logical, but when you are done, it's impossible to tell which mod did what. I put the hi-comp piston in with the stock cam and mild bowl work on the head, and it gave the bike a noticeable boost in power (especially on the bottom) but I wouldn't call it a night and day difference.

So far I have resisted trying a cam, because I make use of the low end power 10 times more than I rev the engine.

Also, keep in mind that depending on the cam and the condition of your stock valve springs, it may be recommended to put in heavier springs. Heavier springs put a bit more wear on the valve train, but will help prevent valve float and other nasty problems.

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I've got the XR's only HRC grind in mine, if you're gonna be in to the motor anyway, yeah it's worth it. Mine'll run with my buddy's KX500.

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I've got a Barnum's cam in mine, and it woke her right up. Toss in a Edelbrock carb, and you've got power for days. :thumbsup:

Where di you get your cam from? Price? would you recommend getting one installed? Thanks :thumbsup:

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If someone answers you will know how durable their cam was... Nine years and still going strong!

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