Special tappet tool needed for valve adjustment?

[SoloScott]

I am about to do a valve adjustment this weekend, but I guess I should ask this before I get things apart. Is the special tappet adjustment tool totally required for the valve adjustment? I was planning on using a small adjustable wrench to hold the tappet while tightening the adjuster nut. Will that work or is the space around the top of the tappet too limited?

[Yellow]

That might work, it's not really tight around there. IMO if the dealer has the tappet tool in stock it's worth the few dollars it would cost you. You could make your own quite easily, check this out:

http://www.maximum-suzuki.com/ibf/index.php?showtopic=29959&hl=valve+tool

[The CyberPoet]

Given that your engine is nut-adjusted and not shimmed:

EDITED:
I carry the Suzuki Nut-Adjuster Tool as part of my stock inventory. PM or email me if you need one.

Cheers
=-= The CyberPoet

[SoloScott]

Thanks for the link, Yellow. That tool is nice. I just might have to make one!

CP, I found a multi-tool online for valve adjustments, but they want $45 for it. My Suzuki dealer doesn't have the tool for sale.

I just finished with the valve adjustment, and it went smoothly. I started using an adjustable wrench, but there really wasn't enough room to use it on many of the tappets. I ended up using needle nose pliers for almost every one. The bike is not all together just yet, but it's raining and I have time.

One tiny hangup was that my feeler gauges only go down to .005 inches and the minimum intake clearance is .004. I try to go for the tightest tolerances, so I used the .005 and made it very snug to that.

I found it odd that all of my valves had gained a little play, except for all the valves on cylinder 4. All of those were tighter than the specs and needed to be loosened. Is this normal or, maybe the last person to do this adjustment made the valves all too tight on #4? The bike now has about 4,850 miles; I did the valve work because I don't know the bike's previous maintenance work.

[The CyberPoet]

CP, I found a multi-tool online for valve adjustments, but they want $45 for it. My Suzuki dealer doesn't have the tool for sale.

The tool you found online is the MotionPro kit probably. Price sounds right.
As for your Suzuki dealer, he may not stock it, but he can order it just as he can order any other part for your bike. Give him the stock number and make him order you one.

I

One tiny hangup was that my feeler gauges only go down to .005 inches and the minimum intake clearance is .004. I try to go for the tightest tolerances, so I used the .005 and made it very snug to that.

I found it odd that all of my valves had gained a little play, except for all the valves on cylinder 4. All of those were tighter than the specs and needed to be loosened. Is this normal or, maybe the last person to do this adjustment made the valves all too tight on #4? The bike now has about 4,850 miles; I did the valve work because I don't know the bike's previous maintenance work.

Question: how cold was the engine? When's the last time it ran?
I ask because if the engine ran in the past 3 to 8 hours (depending on the ambient temp, thus how fast it will cool), the valves could still be warm enough to be longer than ideal. The idea came to me based on your statements.
I always do mine after having it parked overnight; if the dealer does it (summer months -- I'm not standing in 90+ degree heat with 95%+ humidity), I take it to his shop at the end of the business day, so they'll get to it the next morning -- both ways, I know it's truely cold when they are adjusted.

Cheers
=-= The CyberPoet

[trinc]

i would rethink your idea of setting them to the tight end.

tim

[SoloScott]

CP, the bike sat for more than 15 hours before doing the valve job and it was about 50 degrees during the work. That was a good thought, though. Unless I did cylinder #4 and then waited for the engine to cool before moving to the others, wouldn't they all exhibit the same tight tolerances?

Trinc, why rethink setting the valves to the tighter end of the tolerance range? If the recommended range is .004-.006 (I checked the range, it's not up to .007), then why would it be dangerous to set things to .004?

[The CyberPoet]

CP, the bike sat for more than 15 hours before doing the valve job and it was about 50 degrees during the work. That was a good thought, though. Unless I did cylinder #4 and then waited for the engine to cool before moving to the others, wouldn't they all exhibit the same tight tolerances?

No. Valves are individual pieces and do not always drift uniformly.

There are a couple factors possibly at play here.

Let's say the previous owner [PO] never has had a valve adjustment done (didn't get the 600 mile service). The settings may well have drifted since the bike left the factory, as the heating-cooling cycles and engine-break-in period was gone through. Whether they drift one way or the other is strictly speculation -- they don't consistently specifically get tighter or specifically get looser with time and use (otherwise it would be simple to engineer a solution that doesn't require manual adjustments); they can go either way. Thus, they may have gotten tighter.

Or perhaps the original owner did get the 600 mile full service done as the owner's manual says and the mechanic was exhuberant or working off an incorrect spec. Or perhaps the PO did it himself, and misunderstood how to use feeler gauges correctly -- perhaps he put in a .0045, tightened the valve & nut down as far as possible, then pulled the gauge out (with great force). Or maybe the mechanic or the PO checked the valves at the 600 mile service, adjusted #4 because it was too far out of spec, found the rest to still be in-spec by his measurements and stopped. Or perhaps #4 just shifted with time and use.

Or, perhaps your cams bearings wore into the journals better (or worse) and the cams are sitting slightly lower as a result. Or perhaps the valve faces and lips had a .001 thick layer of carbon or sulfated ash build-up on them that got cleaned away by high-detergent fuels or good oil and that accounts for the tighter clearances. Or maybe they had been too tight (say .0038) and the valve stems wore some or the valves bent slightly to compensate. The point is that there is no single "correct" reason that they were at these clearances that we can know of just by looking at the way they are now without knowing what came before...

Trinc, why rethink setting the valves to the tighter end of the tolerance range? If the recommended range is .004-.006 (I checked the range, it's not up to .007), then why would it be dangerous to set things to .004?

Because too loose is safer than too tight; too loose robs you of a little bit of power (mostly when the engine is cold), but too tight causes engine damages (once the engine is up to temp). Let's say the valves are clean as clean can be and over the next 4k miles you wash off a .0005 thick layer of carbon on the valve interface (very easily conceivable under certain circumstances, such as good oils, high detergent fuels, fuel system cleaner [Techron]) -- what happens then to a valve set down to .004 inches clearance? What if your feeler is slightly off spec or worn? Or if you didn't take into account that both valves are activated by a single tappet in the 98+ models (you can get a minor degree of see-sawing between them, meaning each intake valve can measure .004 independently, but if you measure both at the same time, you may not have .004 clearance). Thus, going to .005 - .006 inches is the safer bet in all cases...

According to the factory manual (98+ Kat 600, should also apply to 98+ Kat 750 according to SpecialK's mechanic-friend):
Intake: 0.10 - 0.15mm (.004 - .006 inches)
Exhaust: 0.18 - 0.23mm (.007 - .009 inches)

Cheers
=-= The CyberPoet

[SoloScott]

Great, thanks for the thorough explanation!

I was worried what the PO had or had not done, hence the reason for doing the all-important valve adjustment.

The valve faces and lips? Let me make sure I understand; you mean the valve seating faces inside the cylinder, correct? If there were carbon build-up to accumulate there since the last adjustment, the valves would not fully seat and the tolerance would be greater. If the carbon build-up were removed over time, then the tolerances would tighten.

You made some good points about adjusting valves to the tight side.... If there is carbon build-up on the valve seating faces after the valves are adjusted, the valves will not seat fully and the tolerance will be decreased as measured during this type of work. Since the distance between the tappet end and the piston-end of the valve have not changed, this will not cause interference. With the same line of thinking, if there is carbon build-up at the time the adjustment is made, there could be danger of interference. I'm just trying to make sure I understand the logic behind it

I totally agree with your points about a possibly worn feeler and the chance for rocker arm see-sawing. I don't like the design of a single rocker arm controlling both valves.

Aside from the initial valve check done after break-in, I assumed that it was most likely for rocker arm to tappet distances to increase. This would be a result of cam wear, tappet wear, rocker arm wear, carbon build-up on valve surfaces, seating of the cam, and possibly rocker arm rod wear/unseating. The causes of the tolerance to tighten would be movement of the tappet (which should be held tight with the nut), carbon build-up loss on the valve seating surfaces, valve-seat wear (very likely), seating of the rocker arm rod, and unseating of the cam. I'm just running through what I see as causes of these tolerances to change to save you some typing. Would you agree that MOST of the time, with a well running, clean engine, the valve tolerances will decrease (increased tappet to rocker arm distance)?

Assuming a range in this instance (.004-.006 in), where would you adjust the valves? Should I tear it apart again and re-adjust? That would suck.

[The CyberPoet]

Assuming a range in this instance (.004-.006 in), where would you adjust the valves? Should I tear it apart again and re-adjust? That would suck.

For the intakes, I set mine to effectively .005 -- .004 has virtually no drag or has no drag, .005 drags some and .006 either won't fit at all or only with a lot of force. .007 won't fit at all. After I adjust them, I rotate the engine and recheck them again. I also leave a spare .004 stuck in the adjacent valve during the adjustment to keep the possible see-sawing effect from being included in the clearances (a tip I read some years back for Kat & Bandit engines in the mechanics section of Rider magazine, if I recall the source correctly). Appearantly some firm offers dual-feelers on a single tool to hit both stems at the same time, but my copy of the mag got trashed after being soaked by freshly washed dog before I could order the tool, and I've never been able to track the info down again.

Cheers
=-= The CyberPoet

[trinc]

if you set them to 4 i would measure your guages with a micrometer - the few sets i have are all over the map - i picked the best ones & used them.
btw 4-6 to me means 5.

tim

[TemtnF8]

I set all my valves to the minimum recommended clearance when I did them 600 miles ago, but after reading this thread I think I may re-do them to a medium setting.