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Discussion Starter #1
I found on a post that mentioned factory shim size for the exhaust is 1.825mm. Is this the same size for every CBR250r that comes off the factory line? Also what is the intake shim size (from the factory) if different?

For those that replaced the their shims, what size shim did you go down to for intake and exhaust?

I'm looking to order several shims sized smaller than the factory size to save a trip to the dealer for my 600 mile service. I considered the shim kit but it is costly and comes with lots of size that I will probably never need to use.
 

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You will have to start by measuring the valve clearances first, and if found outside of the factory spec, you will need to remove the shim in question, and measure it to determine which size shim to replace it with. The whole procedure is outlined in the Service Manual.

It would be impossible to order shims ahead of time, and get the ones you would need for your specific motorcycle... you would just be guessing. Due to the fact that these bikes are mass produced, and as such will have varying tolerances, there really is no "standard" baseline shim size that the factory uses.
 

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buy a used shim kit on ebay from someone who was decent enough to note which shims they have already used from the kit. Got mine that way for $40.

Sent from my cm_tenderloin using Motorcycle.com Free App
 

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Discussion Starter #5 (Edited)
Just measured the my valve clearance.

Ex Left
.009 in
Ex Right
.009 in
In Left
.008 in
In Right
.007

I know my exhaust side needs new shim since it is tight. I'll get those replaced. I'm going to leave the intake side alone since they are loose and from what I heard, shims will get tight overtime. (someone let me know if I heard wrong)

Both my exhaust shim from the factory is 1.92mm (.076in). I'll be looking for 1.80mm shims (hope my math is right) at dealership nearby.
 

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Just measured the my valve clearance.

Ex Left
.009 in
Ex Right
.009 in
In Left
.008 in
In Right
.007

I know my exhaust side needs new shim since it is tight. I'll get those replaced. I'm going to leave the intake side alone since they are loose and from what I heard, shims will get tight overtime. (someone let me know if I heard wrong)

Both my exhaust shim from the factory is 1.92mm (.076in). I'll be looking for 1.80mm shims (hope my math is right) at dealership nearby.
I appreciate this man! Thanks a lot.
 
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