Valve Adjustment Time

justducs

New Member
Just got my new shim kit in the mail today! Wish me luck on the valve job this weekend! First go at the 390

Shim Kit.jpg
 

UMZenki

New Member
debating doing this for first service during racebike prep. how much was the shim kit? post up how it goes and what difficulties you find unique to the 390!
 

OldVet

New Member
I'll be curious also...

My dealer said it's a pain in the ass to get to these things, the two that he has done has not needed any adjustment...
 

justducs

New Member
I will try and document it if i can. Maybe make a video or pictures (Which might be hard cause i'm by myself)

The shim kit ended up being $55 from some website called "The Hub" using a coupon code. I have never ordered from them before but its a good price and it got here fast!! I think they are normally around $70. Beats paying $350+ to have the dealer do it!

I'm doing the service Saturday. Ill keep you posted.
 

justducs

New Member
I have seen about a 50/50 on valves in spec and valves out of spec on this forum. Figured i'd waste a day and just figure it out to be safe.
 

OldVet

New Member
Not a bad idea since you are doing yourself all you are out is time and you will have piece of mind knowing they are in spec after you are done.
 

RC390 Fan

New Member
Good luck! When your finished, would you mind posting what the stock shim sizes are? I have a bunch already and it would be great if I could use them on the 390.
 

Bagwell

Member
Country flag
Every motor wont have the same stock shim sizes, but may be a general idea of whats in there. I cant remember what I had, I think 2.60 or so and cant remember the other one but it was a little smaller. Both of my Exh valves were out of spec, the Intakes were fine.
 

UMZenki

New Member
i just picked up a shim kit as well. called the dealer and he said they charge 4 hours for the first service whether its just the valves or the entire thing as the valves will be the time sink. At $85/hr, i think im going to pass, so it looks like im going it alone!!
 

justducs

New Member
alright guys. Well I managed to do the valve check in about 4 1/2 hours. Everything was in spec so no adjustment was needed My exhaust were both at .13 and the intake at .09 and .08. Since they were in spec i didn't go thru the extra effort to remove the cams and check the current shim sizes (sorry @rc390 fan) since i was already at about 4 hours and getting a little tired of being in the bike.

Step one is to remove all of the body work. If you don't know how to do it look in the service guide. It's detailed in there.

Step two is remove the battery and gas tank. There are 3 bolts in the battery box to remove and 2 bolts at the rear of the tank. You have to remove the computer off the front so be careful with that. I ended up zip tying it to the rear sub frame to get it out of the way. There are 4 connections under the tank. 3 tubes and 1 electrical. Just unhook everything and pull tank off.

There is a big plastic cover on top of the motor. I ended up just cutting mine out and not putting it back.



5.jpg
Remove Hose and Plug wire.

4.jpg
Remove 4 valve cover bolts and pull valve cover out of frame. This takes a little work to get it out. Be careful of the gasket!

2.jpg
Shift the bike into 6th gear and rotate the rear wheel (While on a stand) until the timing is at top dead center. There is a little "T" on the top of the timing gears.

I zip tied the timing chain to the cam gears and removed the chain guide. I ended up not pulling the cams because my valves were in spec but this is important if you are going to remove them to keep the timing correct.

1.jpg
I accessed the valves with my shims at these points. It is tight in there... so it was a little tricky. espically the right side intake. You can go inbetween that opening to get at the valve.
 
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