02 Valve change

Jan 28, 2009
3
0
I need advice about changing my valves. I purchased Factory Valves and springs to do the job. Can I do it myself or should I take it to a professional? I have the knowledge to re shim my bike but never went that far into my bike.
 

Matt90GT

Member
May 3, 2002
1,517
1
First off do you have the tools to do it? Valve spring compressor for sure.

You need to lap in the steel valves (exhaust) and just make sure the TI intakes seat properly. Otherwise you will need to have the seats cut.
 

spark250

Member
Feb 7, 2008
128
0
If you are changing the valves why wouldn't you get a valve job? It's almost a given at that point.
 
Jan 28, 2009
3
0
I thought changeing the valves and springs, was called a valve job or explain. Is a valve spring press the only special tool required?
 

IndyMX

Crash Test Dummy
~SPONSOR~
Jul 18, 2006
5,548
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Amo, IN
Yes, unless you need the seats cut. Which you probably don't want do yourself.
 

rmc_olderthandirt

~SPONSOR~
Apr 18, 2006
1,533
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deathmetalkill said:
I thought changeing the valves and springs, was called a valve job or explain. Is a valve spring press the only special tool required?


A "valve job" can mean several different things. Basically, it is repairing anything to do with the valves.

The basic components of the "valve" includes the actual valve, the seat, the guides, the spring and the retainer(s).

The wear on a "valve" will be in three distinctly different areas. The interface between the valve and the seat is the most obvious and will effect performance/durability the most. The valve guides will also wear, and when they get sloppy you will end up sucking a lot of oil into the cylinder past the intake quide and and allowing exhaust gases into the valve cover from the exhaust side. The spring will wear and get weak over time, and it is also possible for the retainer to fail from wear.

The valve and spring is the easy part to buy and replace, but that is only part of the job. If you replace the valve you MUST ensure that the new valves seat properly in the old seats. If you just put new valves in old seats it will probably make things worse than they were before. At least the old valves matched the old seats, the new valves will not.

If the basic cut on the new valves matches the old seats then you might get by with a simple "lapping" operation. You apply a little abrasive compound to the valve and seat, slide the valve in, then press on it lightly as you twist the valve back and forth. You can get a little tool that makes this task possible, it is basically a stick with a suction cup at end. The suction cup holds the valve and then you can twist the stick by hand (rub your hands together with the stick between them).

If the reason that you are doing a valve job is because the old valves were bad then the seats are probably bad as well and lapping won't be sufficient. In this case you need to have the old seats removed and new seats pressed into the head, and then the seats need to be ground to match the valve. This you will not be able to do yourself.

If the guides are bad then the old ones need to be pressed out and new ones pressed in. The guides will be undersized and will need to be reamed out to the proper size. Again, this takes special precision tools that you won't have.

If it was me, I would take the entire head to the shop and have it done professionally.

Rod
 

spark250

Member
Feb 7, 2008
128
0
This is probably mirroring what older than dirt said, but I just didn't have time to read all that. It sounds like you should take this thing to a shop if don't know what a valve job is. There are a lot of components that all have clearances and they need to be checked. (Guides, seats, etc....)
 
Jan 28, 2009
3
0
Thank you Rod. Could not have been clearer. Thank you for the advice. I am taking the head to a professional. The reason I figured I needed new valves and springs was the fact I am at the smallest shim on my intake valves. I believe they have stretched, what I've been told.
 
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