Question about VTEC valve adjustment procedure

I wanna check valve clearance on my 07. I have a factory Honda manual. There's one thing I don't understand, so I'd like some who ACTUALLY HAS EXPERIENCE checking and adjusting these valves to help me.
What is the "slide pin stopper tool" that is required, and what does it do? I really don't grasp or see in the manual what makes it necessary. And since the manual specifically says to do the VTEC valve check first, then take it all back apart and install this slide pin stopper on the regular valves and check those, won't you need 4 of these tools since you are adjusting 4 VTEC valves first, and then the 4 regular valves second on each cylinder?
The dealers in my area have never done a valve adjustment on one of these bikes, I asked both of them. So at this point, I feel I know damn near as much about the VTEC valve check as they do, and I'm not afraid to try it myself.
Thank you in advance.

Erik

 

Read your manual a bit more thoroughly...The slide pin tool is use to engage the VTEC mechanism in the shim buckets of the VTEC operated valves only. The springs that hold the shim buckets against the cam lobes of the VTEC valves also need to be removed at the same time the slide pin tool is inserted. Then the cams are reinstalled to check clearances. After the clearances are checked, the cams must be removed again to take out the slide pin tools and reinstall the springs (and replace any shims if necessary).

The slide pins in the shim buckets are operated hydraulically in normal operation, so you are just simulating them being in operational mode by using the tool.

 

Yes, I gotcha. I figured it out just before I got your message. Thank you.
I don't have the tool, but in the meantime I was able to go ahead and check the normal valves clearance on the two rear cylinders where I hear a noise, and the clearances are fine on those 4 valves anyway.
Something I can't find in the manual is how much back and forth (end to end play) is allowed in the cams?? I can actually move the intake cam back and forth enough to get it to make a knocking noise.....and a knocking noise is what I hear from this thing and have been trying for weeks to find. Am I on to something or is some end to end play allowable?
No it's not the CCT.....been down that road to no avail.

 

I don't have my shop manual anymore (went with the bike), but if the end play isn't specified there, I don't have a clue. I think camshafts tend to "find a location" and stay there once they are rotating, but you never know. I also don't remember what captures them, as in how they are kept from moving back and forth. If you can tell what is supposed to limit their side-to-side movement, it might be worth examining the surfaces to see if they look affected in any way. Good idea, though, especially if the noise you hear while manually moving them is similar to what you have been hearing.

 

I believe my noise comes from one of the VTEC slide pin locks. So here is what I am thinking about doing as a test, tell me if you see a problem.
I want to take the intake cam out, remove the slide pin locks from the VTEC lifters, and re-assemble the bike and see if the noise goes away.
Is there any harm I'm not realizing that can result? The noise is at idle, so I don't need to take the bike and and run it even over 4000 RPM, well before the VTEC even kicks in., but I do need to ride it to get it to make the noise.
I know the VTEC isn't operating at idle, but I still want to try this. I just have to begin eliminating things at this point.

 

Your reasoning is haywire.
Remember what a doctor says, "DO NO HARM"

Go to Google and read about VTEC development. Not kidding.

You could have some noise because of the type of oil being used is not what was specified from the factory. Oil pressure helps to control the slider pin and poppet valve to keep the valve timing in one mode or the other and to prevent it from switching back and forth when the engine gets in the range where it has to choose between the two cam profiles.

You might want to see if oil types could be affecting the VTEC operation at the switch over RPM which you said was 4,000 rpm therby making that clicking noise of the slider pin.


When reading about VTEC it says that in Japan they charge a tax on volume of the combustion chamber(engine size), and so they focused on getting more out of the engine by controlling the cam profile at different rpms and using turbos.

One more thing...If you drive consistantly at the RPM that the VTEC starts to come into play, that may be why you keep hearing the slider pins actuate constantly. See what I mean?

 

Normally I would take offense at some saying my reasoning is haywire, but in this case I can see why someone would say that, so it's OK.
What I will say is that I have a FACTORY HONDA MANUAL....just like I originally stated. It gives the complete valve check and adjustment procedure.
I am not afraid of this engine. I'll get in there and mess with it because the worst I can do is break it. At this point the knocking noise it makes is every bit as dis-pleasing as if it were broke completely, so I'm gonna try some stuff. No dealer has been able to help, I can't seem to find anyone who's had this problem with one of these bikes, so I'm gonna get into it and try my hand at it. Like I say, it doesn't scare me at all.
I use Honda 10W40 GN4 in it. That's not the problem. I've had 5W30, 10W30, 10W40, and 20W50 in this stupid thing. Nothing changes the noise one bit.
I wish I could get a good recording to let you guys listen. Sunday I did about 120 miles, and it was quiet to about the 75 mile mark, at which point it just went HAYWIRE. I'm sitting at traffic lights just knowing the people beside me can hear my knocking engine. It's very embarrassing. And on this day it was bad enough I could FEEL it in the clip on. And if you put your hand on the cam cover for the rear cylinders you feel it plain as day. Only at idle, as I say. I suppose it might be doing it at higher RPM too but I just can't hear it perhaps.

 

I understand. Let us know what you find out in your investigation.
Sorry if I seemed hard on you but I just did not know your skill level.
Many dealerships are deficient as far as experienced mechanics these days.

 

No problem man, I know I'm being a little "off the wall" with all this, but I'm at my wits end. Next step will be to unload it for cheap, if it comes to that.
Once I got the "klack klack klack" out of the front cylinder (CCT) I thought all was well. I was even PM'ing with a guy on here and I told him it was fixed. Then this noise showed up. I tried a manual tensioner to see if it would affect it and it didn't do anything. Quite aggravating.
I'll keep you guys posted.

 

Here is a link to another similar complaint.

2007 VTEC with knock - Honda Motorcycles - FireBlades.org

 

Good on you for having a go.
I think that once you get in there, the cause of the noise will be obvious.
Maybe a broken valve spring, or a broken slide pin spring allowing the slide pin to partially engage at times on the vtec side.
If its a valve spring, its more likely to be on the non vtec side though.
Good luck and let us know what you find.

 

I have a question about cam chain noise. How much chain noise is acceptable? I'm not talking about klacking and clicking caused by a chain that is way loose. I'm talking about a properly adjusted chain operating as it should. I know tighter is not better, so what's an acceptable amount of noise? Can somebody give me some kind of idea?

 

If you overtension it too much with your manual tensioners it will produce a high pitched whine, which is not good.
Too loose and it starts to rattle slightly obviously.
Somewhere in between is what you want.
I found the best way to adjust manual tensioners is with the motor running and finger tight.
Thats not easy on a VFR with the space constraints.

 

I've made what I think is a significant discovery in all of this.
If I take this bike out, and ride it all day and keep it under 6800 RPM and never allow the VTEC to kick in, this noise NEVER happens. But once I hit it hard and the VTEC becomes operational, then after that you'll immediately begin to intermittently hear this knocking noise, and you'll hear it the rest of the day on and off.
So is there a way to either disable the VTEC by disabling the solenoid that opens to allow the additional oil flow, or is there a way to make the VTEC fully operational all the time? I'd like to try one of those things (or even both) just temporarily as a test, if it's even possible. I don't even know where that solenoid is.......

 

Its in the vee of the cylinders under the throttle bodies. See page 5-89 of the service manual.

 

Thanks dogman, I did see that in the manual then.
Lifted the tank, man that thing is down on the very bottom of the vee, underneath everything. I can see the connector but there is no getting to it unless you tear everything apart. I'm not willing to do that. An easier thing to do would be to go right to the ECM and pull the pin/wire that controls it. I think I'll do that instead.

 

Well, I currently have the VTEC deactivated. Have not heard the noise at all. Sure is nice to NOT have to feel that 6800RPM surge and listen to those extra valves clatter when they come on. My opinion has always been that VTEC on a bike is just plain stupid and unecessary to a degree I can't begin to describe. Bike is, of course, pretty down on top end power now without the VTEC working, but it runs good, it's smooth, and NO KNOCK.
I'll run it like this for awhile and if I don't hear the noise anymore, then I know I've narrowed it down to the system that's causing the knocking noise. But then what do I do??? I have no idea....

 

Soiunds like you may need to replace a faulty vtec valve lifter, or at least compoments of it.
I've never heard of one going bad before, but I guess anything is possible

 

I wonder if it is possible that the ECM is flaky? (assuming that is how you deactivated the VTEC per your post). Does the signal go right to the solenoid valve, or does it activate a relay somewhere? I wish I still had schematics... I've seen relays in industrial equipment that get flaky, albeit very rarely. I'm wondering if the ECM output signal is not getting fully pulled into a "low" state, and is supplying just enough current to send a false trigger to the relay (or solenoid). That's almost academic, since it might be easier to replace the ECM than to figure out where the problem is with the existing one.

Thanks for the updates, BTW. There is nothing worse than wondering what the outcome was with weird problems.

 

I'm actually emailing back and forth with a guy from Florida, he has got the exact same noise, and the same exact anniversary model bike.
I'm thinking what you are dogman about VTEC lifters/lock pins being bad. But I don't know what would make the knocking noise even if those parts were bad. It's very strange indeed. But if I decide to get in there and replace stuff, if it does come down to it, it's ALL getting replaced on the VTEC valves; lifters, locking pins, springs, etc. No sense doing it any other way.