Jump to content
Sign in to follow this  

Quick: shims and jetting

Recommended Posts

So my valves are tight after the rebuild.

Left Intake .001 👍

Right Intake .003

Left Exhaust .008

Right exhaust .008

Anyone know what size shims I should get?

And I pulled my plug. What do you think? I might mess with my fuel screw a bit cause it seemed a tad rich.

sparkie.jpg

Share this post


Link to post
Share on other sites

They always tighten up a bit after they seat in. Your manual has the formula on how to figure out your new required shims (but you probably knew that?). I'd leave your exhausts alone, they are good to go. Its recomended to run the exh. valves at .008-.009"

Share this post


Link to post
Share on other sites

Would it be stupid to run them as they are for a ride? Cause I can always bump start it and really want to ride one more time before summer ends. Then after that it would start fine once warmed up.

Share this post


Link to post
Share on other sites

Looks like you are running rich, what main jet size do you have in it right now? I would drop down atleast 5 sizes and then ride again and get a new plug reading. So if you were at a 170, go to a 165.

Exhausts are perfect where they are 👍

Your right intake isn't too bad. But would be nice to get it to .004"

Left intake at .001" I don't know if I would want to ride with it that tight personally. But if I had that clearance on my bike and I didn't have the time to shim it and wanted to ride, I would just ride. So use your judgment on that.

For the Left intake you would want a 0.10mm smaller shim size to get you back to .005" for that intake valve. So if you were at a 1.75 (175), you would go down to a 1.65 (165) -- re check clearance after putting in new shim.

Share this post


Link to post
Share on other sites

To tell the truth I have never messed with my carb and have no idea what my current jets are. Im guessing stock though.

Share this post


Link to post
Share on other sites

If you put in new valves and didn't cut the seats that's why they have moved already, you can shim them but as fast as they have moved you're really asking for trouble because they're going to move again real fast and you're running the risk of sucking a valve into the seat and or breaking off the head of the valve and doing some real costly damage. You really need to have the seats cut and then put in the new valves.

Share this post


Link to post
Share on other sites

he did have the seats cut, and used the OEM shims with the new valves. You need to use smaller shims b/c of the seat cutting.

And valves can seat in around .001"

So, re set your intakes to where they should be.

Share this post


Link to post
Share on other sites

If the valves moved .003" to .004" to close up to .001" when seating in that's way to much and they're going to keep moving. With a good quality seat cutting job and new valves you shouldn't get more than .001" movement after seating in.

Share this post


Link to post
Share on other sites

The point I said earlier was that he used the OEM shims, so the clearances were probably off from the start.

I think you'll be able to ride tomorrow. I wouldn't worry about it too much. Like I said, if I were in that circumstance and didn't have time or parts to shim the valve, I would JUST RIDE! 👍 - If you have the stuff it will take you around an hour to do.

Share this post


Link to post
Share on other sites
If the valves moved .003" to .004" to close up to .001" when seating in that's way to much and they're going to keep moving. With a good quality seat cutting job and new valves you shouldn't get more than .001" movement after seating in.

Well i reused the shims from the old head.👍 So technically they didn't move, just never were correctly set from break in. Do you get what im saying?

Share this post


Link to post
Share on other sites
Yes my seats were cut. So your saying I shouldn't ride tomorrow?

First off I didn't realize you used the original shims after the rebuild so you very well could have been at .001" - .003" from the start. At this point the only way to be completely sure of the condition of the valves is to remove the head and inspect them.

Share this post


Link to post
Share on other sites
Well i reused the shims from the old head.👍 So technically they didn't move, just never were correctly set from break in. Do you get what im saying?

Yeah, if they didn't actually move and that's where they were from the start, just shim them correctly and ride, you'll be fine.

Share this post


Link to post
Share on other sites

weird I put my bike back together, choke on as always when starting, a few blips of throttle, it started 2nd kick. Let it cool down for a few hours tried again later same thing. I dont want to mess with the jetting just yet cause I will probably make it worse.

Share this post


Link to post
Share on other sites

ya if you couldm't have gone riding i would have just gone to milestone with my buddy. but glad it started because i did not want to bump it haha i am to lazy:thumbsup: i am all ready to go for the morning 👍

Share this post


Link to post
Share on other sites

crf rider...can you please clean up your pms...sry for off topic this is the only way to get a hold of you.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×
×
  • Create New...