I read an article in another magazine that you can replace the stock yfz throttle with a honda unit, but I cant find the article or remeber the honda model that works. By doing this it greatly improves the effort needed to work the throttle. Any help will be greatly appreciated.  

Buy a mod quad throttle lever . Its longer so It takes less  effort to push it.If you ride for a long time and your hand starts to hurt you can use your palm of your hand to throttle your yfz.The MQ lever is desighned just for that.It works good I had the same problem.I have no idea about putting honda parts on a yamaha.That doesnt sound right.  

Yes YFZoldman,

You got that correct. We ran a story called "YFZ Throttle Cures" about two years ago. I'm an avid YFZ rider, and I can promise you that the Honda TRX400EX throttle assembly on the YFZ is the very best way to go. Honda dealers don't offer the whole assemby as a kit, but you have to order each part from thumb throttle all the way down to the cable. Call a Honda dealer and order the whole deal. You will be much impressed. I promise.  

Thank you all for the help. I have the extended lever. My daughter has inheritaed the bike and still a little to stiff. Thanks editor i have heard this is the way to go.  

I was wondering how the 400ex throttle hooks up to the yfz. If you say it works what has to be done on the carb?
Do i just need the 400ex throttle cable up and the cable connects right to the carb?

Thanks  

the stock throttle cable should thread into the new Honda housing with no problems. The only thing i have had to do in the past is some grinding of the throttle housing on the inside to achieve full throttle opening. it isnt much but has needed to be done in the past. Just check to make sure and you should be set.