it has been suggest to install wheel extenders on my 650 LE to gain stability, any comments?

 

You don't state why you really want the extenders or what problems you are having to ask about the extenders.
A set of the ITP C-series wheels will set your wheels out further over the stock wheels.
If you are still using the Stock GY Radials, then change them out to a wider tire, like a 26x12x12 rear, have at least a 9 or 10 inch wide on the front, you can still use your stock wheels or go even wider with the C-series units.
I wasn't impressed with the MT Radials on my Cat 650, stability was not good with them at all. I switched to a set of Goodyear Mudrunners 26x12x12R & 26x9x12F, this tire change made a very big improvement. Recently I have gone to a set of the 25 inch Carlise Badlands Radials, these Badlands are great & I will use the Badlands as my summer tires & the MRs as my winter tires.

 

I have a 98 500 I can do almost anything and I won't tip off camber, hills anything... the thing is a rock. However I took the 650 out the front wanted to come up and I needed to ride it like a snowmobile..... so I wouldn't tip over... I have ordered some ITP blackwaters. 26/12/12 for the rear and 26/8/12 for the front I have aired down the tires etc but it still is really tippy... just wondering if the wheel extenders would give me the width I might need.... thanks for the input

 

I hear you on the light front end. My 650 is too the LE model. I also have 2 fender bags mounted on the front fenders (IPI thru Cabelas) & a soft bag on the front rack where I keep my heavier items like my complete socket/wrench kit, other tools, tire repair kit, tow straps, bailing wire & so forth. I did removed the 9 Lb. rear heavy bumper.
Crank up the rear shocks to #5 as a experiment, this helps your 650 from sitting down on the rear suspension. I have my fronts on #4. If you are using the Stock Radial tires, then they need to be aired up to at least 8psi, due to the too soft side walls. When you get your Blackwaters on, you will get better stability. If you are using a hard box on the rear rack try not to overload it with heavy items. Your 650 has the gas tank low but it is to the rear too & bigger than your 500 gas tank, you have allot of weight there, which makes the front lighter.
Since I have been using the fender bags, front bag, switched over to the Mudrunners, been careful about not overloading the rear rack with heavy items, I really haven't felt the lightness up front that much. It still is there if I punch the throttle while climbing a very steep hill but I have learned to be extra careful in doing that. Now I am using a set of the Carlise XTR Badland Radial tires in place of the Mudrunners, I also have them mounted on the high-lifter lite steel wheels & I have found no complaints in the way this Cat 650 handles.