subvalves...Left from right?

Flying W · Post by **Flying W** » 11:19 pm Apr 29 2007

I only have the online manual still and cannot tell which subvalve goes on the left when looking at the exhaust port. Should the cut-out in the lower part of the subvalve be pointing toward the exhaust or intake side?

Post by **Indawoods** » 11:40 pm Apr 29 2007

I believe it goes to the exhaust side... when you actuate it manually it will become clear....

Flying W · Post by **Flying W** » 12:06 am Apr 30 2007

Looking into the exhaust port and turning the main shaft toward the exhaust side of the cylinder (CW if you were looking at the end of the shaft), the subvalves close.

Should they be closed or opened?

Colorado Mike · Post by **Colorado Mike** » 12:14 am Apr 30 2007

The shaft under the round slotted cover on the left side of the cylinder rotates CW, lifts the exhaust port flapper, and rotates the sub port valves open.

Hope that makes sense.

Flying W · Post by **Flying W** » 12:26 am Apr 30 2007

Doh!!

Flying W · Post by **Flying W** » 12:35 am Apr 30 2007

Colorado Mike wrote:The shaft under the round slotted cover on the left side of the cylinder rotates CW, lifts the exhaust port flapper, and rotates the sub port valves open.

Hope that makes sense.

Oh wait.
CW from the slotted cover side (shifter side of the bike) opens the subvalves and rotates the shaft so the exhaust port flapper travels to the rear of the motor.

Me thinks me guessed correctly on which subvalve went in which holie.

A better pic in the online manual or a nicely drawn pic would have been helpful too.

Thanks for the help guys

Gotta get this bike together to see how the RB mods work!

Post by **Indawoods** » 06:54 am Apr 30 2007

Email Cyclepedia about the poor depiction of this area of the manual and they will update it.

Flying W · Post by **Flying W** » 09:59 pm May 01 2007

Indawoods wrote:I believe it goes to the exhaust side... when you actuate it manually it will become clear....

After looking at it with each subvalve switched from side to side, I've decided your advice is the correct advice.

When looking at the shaft under the slotted cover and rotating it CW, the flapper actually goes down (opposite of Colorado Mike's report) and the subvalves open only part of the port (when the subvalves are installed with the cut-out toward the intake side of the motor).

So, they are installed with the cut-out facing the exhaust port and seem to function correctly when compared to how they function when sides are switched.

I sure wish I had more concrete answers than what I received, or a pic from the Factory service manual...but I can always tear the bike apart again if they are wrong.

quailchaser · Post by **quailchaser** » 12:47 am May 02 2007

Flying W wrote:
Indawoods wrote:I believe it goes to the exhaust side... when you actuate it manually it will become clear....
I sure wish I had more concrete answers than what I received, or a pic from the Factory service manual...but I can always tear the bike apart again if they are wrong.

FYI..the exhaust valve (and sub valves) are closed at idle. So, when you install them, you should install them in the closed position:

1. Main exhaust valve goes into the cylinder in the "closed" position...ie. with the tongue thing partially blocking the exhaust port.

2. Sub valves go in. Do not install the collars yet.

3. Sub valve drive rods are then installed...must move sub valves up slightly for the rods to go all the way in. Now the rods are all the way in and the sub valves gears are not yet seated on the rod. Now, look through the exhaust port and turn the sub valve (one at a time) so that it is in the closed position. Now do the same to the other one. I believe the sub valve gear has a notched area on two of the teeth. When installed in the closed position with the rods all the way in, this notched area should be facing you (since your supposed to be looking at the exhaust side of the cylinder).

4. Now that you have the sub valves installed in the closed position and the main valve installed at the closed position with the sub valve rods installed all the way in...you can install the center shaft. To install the center shaft, first hold the main valve lever in place on the main valve pin. Now slide the center shaft in. There is a mark on the gear side of the main shaft that corresponds to the mark on the sub valve shaft on that side. Once that's lined up, you can put the allen bolt through the main valve lever and into the threaded hole in the center shaft.

5. Now you can put the valve rod gear onto the shaft, making sure that the mark on the gear lines up with the mark on the sub valve rod.

Once all this is done, now you can look through the exhaust port and operate the valves manually. They should still be in the closed position. Rotate the center rod. It should only rotate one way (back towards you). This will open the main valve (pull the tongue out of the exhaust port) and rotate the sub valves open. At this point is should be obvious if the sub valves are in the correct side.

If your still not sure...I'll bet if you post pics of the exhaust port with the sub valves installed each way, there are a few here who would be able to spot which pic has them in the proper side.

Flying W · Post by **Flying W** » 09:21 pm May 02 2007

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If your still not sure...I'll bet if you post pics of the exhaust port with the sub valves installed each way, there are a few here who would be able to spot which pic has them in the proper side.

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This is the subvalve on the left of the exhaust port as you peer in. You are looking into the cut-out at the flat vertical surface. This is what it would look like with the motor at idle. There is a little assembly lube on the front lower lip of the subvalve.
Does this look correct?

Post by **Indawoods** » 09:33 pm May 02 2007

I use my fingers to set them myself. At the rest position... I check to see that the port is closed and that the edge of the port valve is resting as close to the opening as possible while still being closed.

That pic has me discombobulated but it looks right to me...

Flying W · Post by **Flying W** » 10:11 pm May 02 2007

Indawoods wrote: That pic has me discombobulated but it looks right to me...

Tilting your head slightly to the right brings the subvalve into the vertical position it should be in.

Okay, I'm pressing on. The subvalve orientation is as you prescribed earlier in the thread. It appears to me to be closed (both subvalves actually) now and should rotate CCW (if viewed from above) when they should, and then they will be open.

Scary. Don't want to ruin something. Don't want to pull the motor this time to switch the subvalves to the other side. The bike needs to be broken in and ridden Saturday. Scary.

Wish someone with a manual could check for an illustration or pic. Probably doesn't have one.

I did email cyclepedia with my request.
Thanks IW

Flying W · Post by **Flying W** » 11:59 pm May 03 2007

Indawoods wrote: it looks right to me...

Must be okay. I started her up tonight with a fresh top end and RB mods to carb and head.

Took a 10 mile break-in cruise tonight, just outside of town on paved roads at moderate RPMs. She is ready just in time for Saturday.

Flying W · Post by **Flying W** » 12:44 am May 29 2007

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If your still not sure...I'll bet if you post pics of the exhaust port with the sub valves installed each way, there are a few here who would be able to spot which pic has them in the proper side.

[/quote]

I finally received my manual and found two pics on 1-9 and 1-10 that show the subvalves in position both open and closed. I am posting them here in case it helps another.

KDXRIDER.NET

KDXRIDER.NET

subvalves...Left from right?

subvalves...Left from right?

here's a pic!!! HELP!! :-)