Anyone ever replace a valve guide in your Raptor head? Easy? Hard? Impossible without the yamaha specific tools? How critical is it to ream the guides? Are they that far off from factory? Will the valve seats always be off after a guide change? TIA

 

No clue David....Bob replaced mine with the valve job. [img]i/expressions/face-icon-small-confused.gif[/img]

 

Just add a little heat and they come right out. Yamaha specific tools are not the only way to do it. Just find something thats the same diameter and beat them out from the cylinder side. You will have to reuse the "seat" springs that sit on top of the guide. The 2 I replaced were tight and would not have lasted without reaming....probably off only a couple thousands though. I would recommend freezing the guides and adding a little heat to the head for installation. The guide should not change the valve seat or height if installed correctly. You really need to do a valve job while you are in there. All you need is some grinding compound and a drill with a chuck that will size down too the valve stem size.
Gary

 

Thanks Gary.
Are you talking of the valve seals that kinda snap onto the top of the guides? What did you use to ream the guide? Looking at the pictures of the tools Yamaha uses I was thinking I could find stuff that would work. The book also talks of heating the head in the oven to remove and install. Thanks again.

 

redskin, nice meeting you at FSW, RapFam is currently repalcing his valve guide, ask him for mre detailed help. PM if you want his email

 

CT, thanks for putting up with me at the starting lines, time after time, LOL. I have his email. Thanks for reminding me. Oh, by the way. Excellent pics of your lady and her friend [img]i/expressions/face-icon-small-wink.gif[/img].

 

We actually have a reaming tool. A small wire brush that fits inside the guide would do fine. Another method would be sanding the valve stem with some fine danspaper for the do-it-yourselfer. A couple thousandths is not going to hurt reliability anyway. Sorry about the late reply bro. Nice pics ctracingraptor....the atvs are OK to.
Gary

 

There is a spring towards the top of the guide that just rolls off. It's primary use is to set the guide at the correct height. It just rolls off the guide. Thats why the guide can only be removed from the cylinder side OUT.

 

my aren't i the popular one.....

 

Excellent, Thanks. I used to be skeered of doing these types of things to my quad. Sheeit, I can remember when I bought my pipe and jetted the carbs the first time. It was like rocket science then. LOL Thanks for the help.