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Posted: 12:43 pm Oct 22 2008
by canyncarvr
Oh..yeah... I read that someplace else.
The RadValve doesn't go in 'upside down'. You are correct in not being wrong about that!
...the OEM reed cage works better......but I already griped about that.
Posted: 01:26 pm Oct 22 2008
by KarlP
"If I remember correctly on the RAD the REED holder and the part that mounts up to the carb is all one piece (unlike the stock one)."
I'm not sure about that; the parts might have been stuck together gasket wise.
You can see that tab from the outside. When I put Boyesen reeds in they mounted onto the stock reed holder. That might not be the case with the Boyesen RAD valve, I'm not sure.
After confirming operation of the KIPS valve, how about you dismount the carb and carb to cylinder boot and confirm the reed holder is in the right way 'round. Of course, if that tab is there you are all set. Once you look at it it makes sense flow wise.
Posted: 01:34 pm Oct 22 2008
by canyncarvr
You're talking Boyesen reeds...he's talking rad (...ically bad) valve. The radvalve does away with the OEM cage AND the white phenolic air guide.
It's its own POS upstream to downstream.....extruded from kyrptonite maybe...
I mean...it's such a
terrific product and all.
Canadian Dave wrote:Boyesen RAD Valves vs. Boyesen Power/ Pro Series Reeds, It’s Your Money.
I’ve used the stock reed valve with both the factory and Boyesen Power reeds and the replacement Boyesen RAD Valve in my 1989 KDX200 and again in my 1998 KDX220. The same RAD Valve will fit both generation of KDX. After some playing around I have come to the following conclusion; when installed in the KDX the RAD Valve does not offer a worth while performance increase over the Power or Pro Series Reeds for the average rider.
Boyesen says, "RAD Valves are designed to correct flow problems associated with today's angled carburetors. The angled position of the carburetor, relative to the cylinder, causes an uneven charge distribution and a loss of flow velocity to the intake ports of the engine. I believe that this is a true statement but expect the results differ depending on the design of the intake system.
If you’re looking to get the best possible performance increase for the money then the RAD Valve just doesn’t make sense. Installing Boyesen reeds will increase the intake velocity at low and high rpm by better controlling the incoming charge of fuel and air. Its nothing earth shattering, but you can feel the results when you ride the bike and you can see the result when rejetting after installing the reeds. A KDX220 with an over-bored carburetor, FMF Rev pipe, performance silencer and Boyesen Power Reeds required exactly the same jetting as the RAD Valve equipped engine. To the average rider the two will perform almost identically. So do you spend the $160 on a RAD Valve or $30 on Power or Pro Series reeds?
I would recommend skipping the RAD Valve, and install the Power or Pro Series reads. If you’re still looking for a performance increase spend the money you saved on something else that will result in a detectable increase in engine performance. Best of all you won't be asking yourself " where did that $150 go? "
..and that doesn't cover the fact that the RadValve reeds have a
lousy lifespan. That's mine
AND others' experience. Frankly, they suck.
...and that's not a
good thing!!
lemmy: If you're interested, I'll send you my OEM reed cage for the cost of shipping. Get a set of reeds mentioned above (I'd recommend the cheaper power reeds..fiberglass, not carbon) any you'll be much better off. Your bike will run better..and you won't wonder if your piston is chewing on pieces of carbon fiber....yet.
Posted: 01:52 pm Oct 22 2008
by KarlP
O.K., back to the basics.
Plug, compression, KIPS, good fuel, clean carb, close enough jetting.
Sometimes when people say a bike has "no bottom end" what is really going on is that for some reason it is running crappy at that rpm/throttle position. There really is no magic to this stuff. If everything is close to right it ought to run well.
Easy to say from HERE.
I have been run around the block a time or two though, chasing gremlins of my own making.
Posted: 01:55 pm Oct 22 2008
by canyncarvr
And after a couple of weeks of trying to sort out the 'problem' on some forum, you find out the rider that says his 2T has no bottom end is coming off a huge 4T............
Posted: 03:20 pm Oct 22 2008
by lemmy
canyncarvr wrote:Oh..yeah... I read that someplace else.
The RadValve doesn't go in 'upside down'. You are correct in not being wrong about that!
...the OEM reed cage works better......but I already griped about that.
Yeah, I have read other places that the RAD doesn't help anything at all. But I haven't heard that it may actually be worse. The stock cage came with the bike. So I will change that out and go back fiberglass. I have heard the carbon might be marginally better but don't last long.
Posted: 03:31 pm Oct 22 2008
by lemmy
Ok, I haven't been on a dirt bike since 1985 and I was riding an XR75 or an XR125. I have been on street bikes since 1993. I just got this bike in July but was recovering from a race track injury so I have only recently started riding the KDX. So I have never ridden on a 2T before but with the with the exception of a 1/2 mile ride on a CRF250X and a short trail ride last Saturday on a KTM 450EXC, I have not been riding 4T either (except on the street).
The gas is 93 pump gas (no ethanol) with Motul 800 2T @ 44:1. The plug is the 8RES gapped correctly and brand new. The jetting is 155 main, CEL needle (clip in 3rd position) 35 pilot with air screw 1.75 turns out. I have tried pilot of 35, 38, 42. When I got the bike it had 165 main, stock needle in 3rd position and 45 pilot with air screw almost all the way in. I haven't checked compression and the carb is very clean. I have also checked the float height twice and it is perfect.
Posted: 05:18 pm Oct 22 2008
by lemmy
Ok, I took the slotted cover off on the left side and revved the engine very high and i saw the nut looks like it just twitched a bit but didn't move. So I assume the first think I should do is drain the oil and coolant and take off the right side covers to inspted the bottom end of the kips governor rod?
Posted: 06:00 pm Oct 22 2008
by lemmy
I tried to actuated it manually with a 10mm on the left side and it wouldn't budge. I took off the cover on the right side (just the small cover that covers the left hand thread bolt) and then supported the rod and removed the bolt. After that it actuated from the left side very easily. So it looks like something is jammed or broken down in the clutch area where the bottom of the governor/actuator rod is.
Posted: 06:28 pm Oct 22 2008
by scheckaet
So it looks like something is jammed or broken down in the clutch area where the bottom of the governor/actuator rod is.
don't run your bike till you sorted it out.
Posted: 07:16 pm Oct 22 2008
by lemmy
As I was taking stuff off so I could remove the right side engine cover, I decided to lightly twist on the actuator shaft just to see if it felt locked up now that it was decoupled from the horizontal shaft. I turned easily in one direction (felt like it was overcoming a spring) and in the other direction it didn't move. This was exactly how I thought it should work. But I made the mistake of turning a bit too much in the direction that had spring resistance and the small advance lever pin popped out of the groove. I took the cover off and sure enough that is what had happened. When I put it back in the groove it felt perfect and I don't think anything is wrong down in there.
I am thinking the guy before me just had the area where the actuator rod connected to the horizontal shaft timed wrong. There is no white paint on the horizontal shaft gear so there is no way to know how to time it correctly. I think I can get it close to right (buy having the rest position of the actuator rod set with the kips not engaged) but I guess I could have it off a tooth whhere the plate engages the horizontal shaft gear. Is there any way to get this right without any marks on the shaft gear?
Posted: 07:34 pm Oct 22 2008
by scheckaet
Not sure if this is what you're talking about but here is a pic. the dot should line up with the straight line.
Assuming the sub valve are timed correctly, should be good
Posted: 07:38 pm Oct 22 2008
by scheckaet
same here, should see a dot and another mark (it's been awhile since i did it...)
Posted: 08:15 pm Oct 22 2008
by lemmy
the manual i have (cyclepedia) says white should be on the gear on the 2nd picture, but i don't see it on mine. however i do see a mark on the other side of the gear on the horizontal shaft so I am going to use that and align with the dot on the plate. should work. thanks!
Posted: 10:32 am Oct 23 2008
by september9
Question for the pro's.
In scheckaet's post he shows a picture of the shaft with a nut on the top. Is this the way it is supposed to be?
My bike doesn't have the nut on top or the threaded shaft that it goes onto. When I did my top end, it had a bolt (with the head rounded) and it screwed into the shaft (which the threads were stripped). I had to tap new threads into the shaft and I replaced the bolt with an allen headed one.
Do I need to get a new actuator shaft?
Posted: 11:04 am Oct 23 2008
by scheckaet
How's the claw kept in place?
Posted: 03:22 pm Oct 23 2008
by lemmy
I got everything put back together and when I take of the slotted coverI can see it activate when I rev it up. I was just wondering how fast is this supposed to activate and release? It activates pretty quickly, but it is somewhat slow to release when the revs go back down. I have ridden it and can't believe the difference it has made. This bike has so much power down low. I think it feels as good or better than the 4T I have ridden. Also, I can now hear the KIPS rattle. I never did hear it before and wondered what everyone was talking about.
Posted: 03:47 pm Oct 23 2008
by scheckaet
KIPS rattle? Always thought it was more of a clutch noise. Can't say I really heard (or even tried) the kips activate. Someone else will proly shime in to confirm
Posted: 04:22 pm Oct 23 2008
by september9
scheckaet wrote:How's the claw kept in place?
That is why I did this: I had to tap new threads into the shaft and I replaced the bolt with an allen headed one.
I don't have the stud and nut combo. I have a bolt hole with a bolt in it holding the claw in place. If I get time tonight/this weekend I will try to get a picture of it.
Posted: 05:01 pm Oct 23 2008
by KarlP
Lemmy-
That sounds about right- it kind of snaps open and closes slow. You can get it to open a little smoother and a bit earlier by removing that ball detent and spring under the LH slotted cover.
September-
Sounds like someone broke the threaded end off your actuating shaft and then did a repair. I'd worry a bit about it coming loose in use. It had backwards threads for a reason. If it doesn't come loose and can be timed O.K., you might leave it alone.