06 kx250f valve seats

Well its time for my intake valves to be replaced. Could someone please tell me the angles these seats need to be cut at. Also if there is a tool I could buy to do this myself. I know someone with the machine that cuts the valve seats on cars and diesel trucks but I'm not sure if this would work. Thanks for the help:thumbsup:

After doing some reading myself, it seems that the 3-angle valve job consists of the seats being cut at 30-45-60-degrees to allow for more flow at initial lift of the valve off of the seat. Stock seating occurs at 45-degrees.

Former posts seem to iterate that a SERDI-type machine should be used for the seat cutting as it is more precise with squaring the seat with the new valve. There is also another "old-school" way of cutting the valves but former posts seem to iterate that this should only be done by someone that is highly-experienced with modern four strokes and the manual technique (in other words, do not let your local motorcycle technician cut your seats).

Hope this was helpful.

Serdi or Rottler make machines that will cut seats in a motorcycle head. You can also get a kit from Neway that will allow you to cut your valve seats manually. These kits are about $500. I borrowed a friend's Neway kit when I rebuilt my KX250F head this winter. The secret is to take as little material away as possible to make the valves seat perfectly.

Alright thanks for the help guys. Is it mandatory to cut the seats or is it possible that They are still in good shape? I will tear down the bike tomorrow and check it out

In the past I had to have head work done. Someone recommended that i send the Head into MXtime.com. They will cut new seats, completly replace the valve assembly with stainless steel valves and HD Springs and ship it back to you all for $425. Right now there turn around time is advertised to be 1 to 2 days. :thumbsup:

Alright thanks for the help guys. Is it mandatory to cut the seats or is it possible that They are still in good shape? I will tear down the bike tomorrow and check it out

The seats need to be cut in order to maintain perfect fit with the new valves. The valves cannot be lapped in either, because it will just destroy the valves.

I already have the valves and I don't like taking my stuff to other people. I like to learn how to do it myself. I will buy the $500 tool before I take my head anywhere to get it done. Just wondering if that is really the only option to this.

Also which model neway kit would I need. There are a few different ones. Thanks

Just contact Neway and tell them which bike you have. They were able to provide my friend with a list of product numbers for his 03 CRF 450.

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