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Discussion Starter · #1 ·
I Was curious since my Intake Valves on my 2005 TRX450R have the smallest shims you can get and they still are to tight I cannot even fit my Smallest .0015" Feeler Gauge in the Intakes!

I have adjusted my valves 4 Times the past 3 years of owning my quad my valves are now on the Slimmest Shims you can get I ride allot of High RPM's so that's why they are worn out now FYI.

I was told by a guy I know who is a Honda Technician he said I can actually Run my bike with no Shims for the Intake valves and get enough Clearance temporary possibly maybe a bit over .006 and it should be fine he said till I can replace my Intake Valves. Can I actually do this?

My quad is Super hard to start when it's cold and I know it's because of the Intake Valves being so tight. I have allot of Experience on working on Bikes but I never heard of running no Shims but if I can I will get as much life out of them as I can till I throw my High Compression Piston in and then I can do my valves then.
 

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The thinnest shim available is a 1.20 - if you have less than zero clearance (-.05) then you would need a 1.00 shim to get correct clearance - if you take out a 1.20 shim and don't put in a 1.00 shim, then you have a calculated clearance of about 1.15mm which is over .035 inch.

If you get correct clearance with no shim, then the bucket is pushing on the spring retainer and not the valve. If this is the case, you will be riding a potential grenade.

It's your engine. If you trust your Honda technician, then go ahead, but it will never be done in my engine!

It's not just the high rpm's that wear out the valves - it's a combination of heat, degree of filtration on the incoming air and the number of times the valve contacts the seat that determines how often the valves need to be adjusted. Usually it's dirty air that wears the valves the fastest.

When my engine had Titanium valves in it, the valves needed adjusted 3 to 4 times a year. As the valves wore, the frequency of adjustment increased to about once a month. When it got down to having custom 1.00mm shims in it, I replaced the valves with Faction MX stainless steel valves - now my valves only need to be checked about once per year.

FYI -you can take some shims into a quality machine shop and have them ground to whatever thickness you specify
 

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Discussion Starter · #3 ·
Thanks for the Reply, that is kind of what I figured if I were to Try and run it with out shims the Buckets will push the Keepers out and drop a valve at some point.

That is why I got on here to have a 2nd opinion I will not do that and just get new Valves and Head Gasket kit, I Would take my shims in but There is such a Low Clarence I believe it's better if I throw in new valves.


Makes sense thanks for the reply man!
 
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