vtec valve check

Hi all,
I've checked my valve clearances on my Vfr800vtec.
All the clearances both vtec valves and normal valves all seems to be on the small side, I thought that a bike with over 50000 miles on the clock the valves would have opened up not closed.
There are only two shims I have to change and one vtec followeri have to change
Any body else had these readings

 

If you mean you had less valve lash than spec, then that is what typicaly happens.
Keeping things simple here:
Valve seat recession (Google it) causes the valves (head and stem part) to move further into the head (due to the seat receding) and closer to to the cam follower. That gap between the valve stem and follower is the Lash. When this gap gets less and less till you have zero lash or negative lash and the valve never gets to close all the way because its always being in contact with the follower. This causes low compression obviously and can cause burned valves because the valve transfers heat to the head when it's closed.

(At least this is how I understand it)

 

I thought it would be something simple like that? Not :hss:

 

Just out of curriosity what was the smallest gap you had? I'm trying to decide when to check mine. I almost waited to long on my atv. It had zero lash. It calls for valve inspection every 100 hours or 1000 miles though.

 

is this something that i need to worry about on my 07? if so, when do i need to check them? thanx

 

Honda calls for a valve inspection every 16,000 mile but most people skip the first one. I did. Most people don't find the valves much out of spec on the second inspection at 32,000.

 

. some phots

Well then as to the valve gap size or should I say lash size,the rear bank of cylinders were all in the specified
Tolerances,but as for the front bank of cylinders thats another story,
One of The vetec intake valves had a gap of 102 when you do the formula on that you need a new follower the size of around 170 and of course honda dont make that size.
For the two exhaust non vtec vatves I had a gap of 279 each, and when you do the formula on the you need a shim size of 097 and you guest it honda dont sell or make that size
So what I will end up doing is puting the smallest shims and follower in that I can get, not necessary genuine
Honda parts.

 

I hate this shim and bucket design that honda uses. My polaris has a set screw that pushes on the top of the valve stem and a jam nut to hold it in place. It's as easy as remove valve cover, loosen jam nut, turn screw in or out, check with feeler gage, tighten jam nut and put valve cover back on!

 

With a screw and locknut adjuster, the valve inspections must be closer together. Also, those kinds of arrangements are not conducive to high RPM operations and subject to a lot of valve float. That's why most manufacturers of high performance motorcycle engines use shim under bucket adjustments. They're a royal PITA to adjust for sure. But the performance gain is their main advantage.

 

I was just considering whether to do this task, and after reading through the 6th gen official Honda manual, and then watching this video on YouTube https://youtu.be/XEimE9DptP4, I was not enthused about tackling this task. I did the 16000 mile adjustment on my 2006 GSX-R 1000 a few years back, and that was pretty straightforward. Plain old shims and buckets, and most of the valves were in spec, with only 2 or 3 were in need of adjustment.

However, whoever assembled it must have been sleepy, because one of the bushing sleeves was jammed up near the cam, and thankfully did not damage the engine!

In any case, after pricing the cost of just doing the inspection (assuming everything is in spec), it'll cost $116 + shipping.
- Front & rear cylinder head gaskets: $31.10 ea
- "B" gaskets: $5.62 x 4 pieces = $22.48
- New timing hole cover o-ring = $3.84
- I don't have the tools to fabricate the slide pins, and it's a poor cost-benefit consideration to get those tools just for this task, so those will be $27.69 from Honda.

That's a steep price just to look at something that's in spec.
Since it seems that the consensus is to leave well enough alone until 32k, I'm okay with that.

 

Since I'm no mechanic by any means, before paying the $$ to find out everything is aok, can a compression test give any clue whats goin on in thar?
I have 30,500 on my 02 with no adjustment and runs great with no strange noises.......
Thanks

 

The way I look at it is this ... no noise? No problem.

At 50K get it done regardless ... you're probably good for another 50K and what did it cost you per mile in the end? Cheap insurance.

 

Errmmm...nope. If you have low compression due to no valve clearance then you are already in valve burning territory. Compression values can also be affected by leaky rings. Valve clearance needs to be checked with feeler gauges. The benefit of the shim-under-bucket system is they change pretty slowly so frequent adjustment is not needed.

 

Funny , I just asked my neighbor and got the same exact response about leaky rings. Thanks man

 

Just had mine checked about 2 months ago at about 16K miles. All in spec, but secondary valves a PITA as the mechanic explained it.
Afterwards I was thinking, heck, if I'd have known that, I would have only had him check the primary valve clearances since they're active all the time, and the secondary valves fairly rarely active.
Thoughts...?