Which year did shim adjustments quit

[ron bayless]

I love the gs more than any other ujm. But the shim and bucket thing is a terrible design.did suzuki ever change to locknut and setscrew? I dont like the looks of the bandit which was the new generation gs as far as i could tell.

[roeme]

Never?

It is my understanding that the direct-acting OHC mechanism is superior to a design involving rockers, and is an evolution of the latter. Yes, adjustment is fiddly compared to locknut/screw, but in every other aspect it's better. Lower adjustment intervals, less moving parts, less play, capable of higher RPM's, lesser impact by thermal expansion....etc. etc. etc.

[TxGSrider]

I dont know about the bandits for sure, but I think the 1200s kept the old style gs style rocker are style using the nut/screw arrangement.

Also if you ever want any help wrenching or you get a bike and want to go riding, theres a couple of us just a few miles from you. Just let me know.

[jsandidge]

The 16 valve GS's used the setscrew and locknut adjusters.

[cowboyup3371]

The Bandit 1250 uses a shim UNDER bucket design but I was fortunate to not need to change any when I did my check this year (bike has 97,000 miles on it, 21,000 is from me) and neither had the PO during his checks based on his meticulous records

[Rich82GS750TZ]

I love the gs more than any other ujm. But the shim and bucket thing is a terrible design.did suzuki ever change to locknut and setscrew? I dont like the looks of the bandit which was the new generation gs as far as i could tell.

Ron, "terrible design" or not, even many modern motorcycles with OHC (over-head cam) use the shim over buck valve clearance design, so there must be something to it. The valve adjustment process is not difficult, but may require that you have various sizes of shims on-hand, or wait with the valve cover off while you get the correct new sizes.The GS bikes that most of us concern ourselves with here, from the 70s and 80s, fall into 2 basic categories:

8 valve engines with shim over bucket, characterized externally with round cam end caps;
and
16 valve engines with screw adjusters, characterized externally with rectangular cam end caps, maybe easier to adjust clearance but there are 16 valves to check, not just 8.


then
Suzuki changed the 16 valve engine design in some mid 80s bikes. These do not have the cam end caps at all.


Edit to add: You've been a member here for 16 years, with over 1500 posts? That's a long time to kick tires. What's keeping you from getting a bike?

[rphillips]

Orig. question, What year did shim adj. stop, not sure if it did. The rocker & screw adj. started in 1980 with the TSCC, 4 valves per cyl. engines, but the 2 valve models kept the bucket shims. Back then the GS's had the shims on top of the buckets & were relatively easy to replace. Other UJM's, Kawa. & Honda, sometimes put the shims under the buckets, cams had to be removed to adjust the valves. Not sure the entire Suzuki history but the 1200 bandits kept rockers with screw adj., thru 2005, no Bandits in 2006 then the Bandit returned with the 1250 in 2007 & at that time had the bucket & shims back, but this time with the shims "UNDER" the buckets. I couldn't say the shim & bucket was a terrible design, but can sure say the shims "UNDER" the buckets makes the valve adjustment thing way the heck more aggravating. I've had a lot of miles & never a problem with the screw adjustors but have heard of problems when using radical cams.

[hank2]

It's not an inline four, but the Suzuki DL650 V-Strom L-twin used shim under bucket. I believe the DL1000 V-Strom used the shim over bucket. This was on the first gen models 04-11 DL650 and 03-12 DL1000. I don't know if that changed on later models. The next gen GL650 used a somewhat different engine from the Gladius.

Off topic a bit, but I own one car with a shim under bucket mechanical lash valve train and have owned a least a couple in past. That aggravates me much more than it's use on a bike. The hydraulic lash DOHC do fine up to 6500rpm.

[bwringer]

As noted above, the answer to the question is "never". Shims shrunk and went under the buckets, making valve adjustments an even bigger PITA.

The DL1000 does use shim under bucket valves. However, the camshafts are driven by a gear (which is driven by the cam chain), so valve clearance adjustments are much easier in the DL1000 than the DL650 since you don't have to monkey with the cam chain.


The DL650, DL1000 and pretty much every modern OHV bike (like my FJ-09) uses shims UNDER buckets. Much lighter, more reliable, better able to withstand high RPM, and modern materials mean that valve check intervals can be longer, with less likelihood of needing a change. But yeah, when you need to swap a shim, out come the camshafts. Bleah.


The KLR650 is certainly not a modern bike, although it's still in production; it uses shims OVER the buckets much like a GS (and the shims are only .5mm different in diameter), but Kawasaki for some reason really screwed us over; you cannot remove the shims with a tool like a GS. You have to remove the camshafts.



A few cars (like some Toyotas) actually use shims as well, or lifter buckets of different thicknesses. Car engines are beefier all around and turn at far lower RPM, and it's literally unheard of to ever need to actually change a Toyota valve shim. You're supposed to check them every 60,000 miles or whatever, which I did when I had a few of these engines under my care, but the clearances were always within spec up to 300,000 - 400,000 miles and beyond.


Since you don't have to pull the camshafts, 8V GS shim adjustments are honestly far easier and faster than farting around with the screw and locknut arrangement on 16V GS models. Half the valves, and no delicate dance of tightening without moving the clearance, using two feelers in one fist, etc. And it's pretty much always clear which shim to install. Of course, the caveat is that you need a goodly assortment of shims on hand and way to measure any with worn numbers, and using the tool correctly is an acquired skill. Once you get the trick (apply sideways pressure toward the bucket), it won't pop off.

[Cipher]

modern materials mean that valve check intervals can be longer, with less likelihood of needing a change.

What valvetrain materials are in present today that did not exist 45 years ago?
KBike is a royal pain to check valves but its "shims" have a wear surface much greater than suzukis threaded adjuster's tips.

KBikes rarely need adjustment across multiple service checks.
My 550 always tightened up according to the shop guy. But not now that I do the check myself. That's a sad revelation.

It seems Suzuki used the one part on every threaded adjuster bike they made for 30 yrs or so.


This Suzuki 12842-49201 TAPPET ADJUSTER SCREW fits the following models and components:


Aftermarket Parts Engine Valve Train Tappets


Suzuki Motorcycle 1982 GS1100ES CAM SHAFT - VALVE (MODEL D)


Suzuki Motorcycle 1983 GS1100E CAM SHAFT - VALVE (MODEL D)


Suzuki Motorcycle 1982 GS1100E CAM SHAFT - VALVE (MODEL D)


Suzuki Motorcycle 1983 GS1100ES CAM SHAFT - VALVE (MODEL D)


Suzuki Motorcycle 1988 GSX-R750L CAM SHAFT - VALVE (MODEL J/K)


Suzuki Motorcycle 1989 GSX-R750L CAM SHAFT - VALVE (MODEL J/K)


Suzuki Motorcycle 1990 GSX-R750L CAM SHAFT - VALVE (MODEL J/K)


Suzuki Motorcycle 1990 KATANA - GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1989 KATANA - GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1991 KATANA - GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1993 GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1995 KATANA - GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1992 KATANA - GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1988 KATANA - GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1994 KATANA - GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1996 KATANA - GSX600FT CAM SHAFT - VALVE (MODEL J/K/L/M)


Suzuki Motorcycle 1990 GSX-R750L CAM SHAFT - VALVE (MODEL L)


Suzuki Motorcycle 1988 GSX-R750L CAM SHAFT - VALVE (MODEL L)


Suzuki Motorcycle 1989 GSX-R750L CAM SHAFT - VALVE (MODEL L)


Suzuki Motorcycle 1983 GS1100E CAM SHAFT - VALVE (MODEL Z)


Suzuki Motorcycle 1983 GS1100ES CAM SHAFT - VALVE (MODEL Z)


Suzuki Motorcycle 1982 GS1100ES CAM SHAFT - VALVE (MODEL Z)


Suzuki Motorcycle 1982 GS1100E CAM SHAFT - VALVE (MODEL Z)


Suzuki Motorcycle 1993 KATANA - GSX600F CAM SHAFT VALVE (J/K/L/M)


Suzuki Motorcycle 1983 GN250 CAM SHAFT/VALVE


Suzuki Motorcycle 1982 GS750T CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS550ES3 CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS1150EF2 CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS1150ESG CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS550EF CAM SHAFT/VALVE


Suzuki Motorcycle 1980 GS1100E CAM SHAFT/VALVE


Suzuki Motorcycle 1980 GS1100-LT CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS550ESF CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS550ESG CAM SHAFT/VALVE


Suzuki Motorcycle 2009 GZ250K9 CAM SHAFT/VALVE


Suzuki Motorcycle 2009 GZ250L0 CAM SHAFT/VALVE


Suzuki Motorcycle 2010 GZ250L0 CAM SHAFT/VALVE


Suzuki Motorcycle 2008 GZ250K9 CAM SHAFT/VALVE


Suzuki Motorcycle 2005 GZ250 CAM SHAFT/VALVE


Suzuki Motorcycle 2005 KATANA - GSX750F CAM SHAFT/VALVE


Suzuki Motorcycle 2006 GZ250 CAM SHAFT/VALVE


Suzuki Motorcycle 1992 GSX1100GP CAM SHAFT/VALVE


Suzuki Motorcycle 1992 KATANA - GSX750FT CAM SHAFT/VALVE


Suzuki Motorcycle 1987 GSX-R750H CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS550ES CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS550L CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS550ESG CAM SHAFT/VALVE


Suzuki Motorcycle 1993 KATANA - GSX750F CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS1150 CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS1150ESE CAM SHAFT/VALVE


Suzuki Motorcycle 1985 SP250 CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS550ESF CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS550ESG CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS1150EG CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS1150ES3 CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS300L CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GS1150ESG CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GS550EF CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GS1150EF CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GS1150EF2 CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GSXR750R CAM SHAFT/VALVE


Suzuki Motorcycle 1989 KATANA - GSX1100FP CAM SHAFT/VALVE


Suzuki Motorcycle 1990 KATANA - GSX1100FP CAM SHAFT/VALVE


Suzuki Motorcycle 2004 BANDIT - GSF1200S CAM SHAFT/VALVE


Suzuki Motorcycle 2004 GZ250 CAM SHAFT/VALVE


Suzuki Motorcycle 1981 GS750E CAM SHAFT/VALVE


Suzuki Motorcycle 1981 GS750L CAM SHAFT/VALVE


Suzuki Motorcycle 1993 GSX1100GP CAM SHAFT/VALVE


Suzuki Motorcycle 1991 KATANA - GSX750FT CAM SHAFT/VALVE


Suzuki Motorcycle 1997 BANDIT - GSF600S CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GS1150EG CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS550ES3 CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS550ESE CAM SHAFT/VALVE


Suzuki Motorcycle 1998 BANDIT - GSF600S CAM SHAFT/VALVE


Suzuki Motorcycle 1982 GS300L CAM SHAFT/VALVE


Suzuki Motorcycle 1982 GN250 CAM SHAFT/VALVE


Suzuki Motorcycle 1981 GS1100E CAM SHAFT/VALVE


Suzuki Motorcycle 1980 GS750E CAM SHAFT/VALVE


Suzuki Motorcycle 1987 GSXR50 CAM SHAFT/VALVE


Suzuki Motorcycle 1987 GSX-R750G CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GSX-R750G CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GS550ESE CAM SHAFT/VALVE


Suzuki Motorcycle 1986 GS550ES3 CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS1150ESE CAM SHAFT/VALVE


Suzuki Motorcycle 1985 GS550EF CAM SHAFT/VALVE


Suzuki Motorcycle 1982 GS750E CAM SHAFT/VALVE


Suzuki Motorcycle 1982 CAFE - GS1000S CAM SHAFT/VALVE


Suzuki Motorcycle 1982 SP250 CAM SHAFT/VALVE


Suzuki Motorcycle 1983 CRUISER - GS300L CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS550EF CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS550ESE CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS550ESF CAM SHAFT/VALVE


Suzuki Motorcycle 1983 KATANA - GS750S CAM SHAFT/VALVE


Suzuki Motorcycle 1983 SP250 CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS750ES CAM SHAFT/VALVE


Suzuki Motorcycle 1983 GS750E CAM SHAFT/VALVE


Suzuki Motorcycle 1991 KATANA - GSX1100FP CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS1150EG CAM SHAFT/VALVE


Suzuki Motorcycle 1984 GS1150ES3 CAM SHAFT/VALVE

[ron bayless]

I dont know about the bandits for sure, but I think the 1200s kept the old style gs style rocker are style using the nut/screw arrangement.

Also if you ever want any help wrenching or you get a bike and want to go riding, theres a couple of us just a few miles from you. Just let me know.

Thank you.theres a 2valve gs 1000 at g and s suzuki i have my eyes on.i owned 2 850gs and one gs 1000L. I liked the L the most.i replaced all the gaskets top to bottom on it.got to know the engine internals.

[wymple]

I've owned and adjusted both styles. The 16 valve screw adjustment is easier, and it's not close. But only once or twice ever needs done on the bucket & shim style. I set those on the loose side so the adjustment lasts longer between intervals.

[bwringer]

What valvetrain materials are in present today that did not exist 45 years ago?

For the most part, valves and valve seats are MILES more durable nowadays than they were in the '70s and '80s.

Generally, cam lobes and buckets or shims do not wear significantly (unless something goes wrong, like an improperly hardened part, or oiling issues). Changes in valve clearances come about because of wear at the rim of the valve where it contacts the valve seat. The valve seat itself can also wear, but for the most part on most bikes, it's the valves that wear.

- If the cam lobe or bucket/shim wear, then clearances would increase
- If the valve or valve seat wear, then clearances decrease, which is the normal experience.

Some bikes are more durable than others in this respect.

Sometimes there are manufacturing issues; for example, the Yamaha FJR1300 had a run of soft valves that would go tulip-shaped, so they replaced a lot of these under warranty.

The usual pattern with modern bikes is that the clearances sort of "bed in" at the first couple of valve clearance checks, and after that they change very little if at all. For example, I bought my DL1000 at 40,000 miles and soon did a valve clearance check, since there were no records or signs of this ever being done (it's supposed to be done every 15,000 miles). Seven out of the eight valves were too tight and corrected. I sold the bike with about 117,000 miles, and at the last check at about 115,000, the valve clearances had still not changed at all.

On my FJ-09, valve checks are called for at 24,000 miles. I bought mine with 22,000 miles and went ahead with the first valve check. All 12 valves needed shim swaps (two intake valves were technically in spec but at the lower end; I swapped these anyway to get them into the upper end of the range). The consensus from higher-mileage owners is that I may need to swap a few shims at the next valve check, but that they generally stay very stable.

On a GS (and most bikes), the valve seats don't seem to wear much, if at all; the wear seems to happen on the valves. After you take apart a few engines, you'll notice that the "ring" around the valve where it seats is bigger after a lot of miles.

The outer edge of the valve also starts out square and slowly gets "sharper" over the miles. This process is faster on exhaust valves because of the intense heat, so it's a lot more common to need to swap exhaust valve shims.

[Jedz123]

I did the Valves (Shim over bucket with roller rocker assembly) at 20K miles on the Bonneville and it's been rock solid at 40K, 60K and 8)K miles. I will have Triumph do a full work over at the end of this season when I get the bike to 100K miles. I'm guessing the Valves again will be dead nuts even. Shims on the Bonneville is easy, remove the rocker arm to replace the shim, Cam stays in place & time. No crazy tools or techniques required

All I can say is I ensure to see shim over bucket in the valvetrain of my high mile motorcycles moving forward. Lock nut adjustment ALWAYs seems to go out of whack over enough time. The Suzuki TU250X needed the exhaust valve adjusted 3 times in the 10K miles I owned the bike (Lock nut adjustment).

As for the GS models I preferred doing the valves on my lock nut rocker 16V GS750 I had vs the shim 8/4V bikes. They seemed to go out of whack every 3-5K miles regardless if it was shims or lock nuts.... With the lock nut adjustment I could guarantee the valves were back in spec regardless if I had the shims in stock or not... All I needed was my feller gauges.

Valve clearances are more set and forget after the first service with shim bikes these days... Which is nice. All my modern high mile bikes with shims, were only set once and never touched again (FZ1, Concours 14, Bonneville T120). The Bandit 1200 being my first high mile bike (with lock nut adjustment) was adjusted annually or every 15-20K miles and yes it was out of whack every year however maintained a healthy service life to 104K miles (80K where my miles).

[bwringer]

Thanks for the variety of experiences, Jedz.

And yep, keeping shims on hand is the big caveat for 8-valve GS engines. I've built up a pretty good collection over many years, but the things are expensive. I'm fortunate in that Cycle Recycle II is a 20 minute ride from my house, and they stock GS shims. For my GS850, I keep a list of the sizes I'll probably need next and make sure my kit is stocked up before the next session. As many have found, the 2.75 and larger shims are pretty useless after some miles. A few of mine are down to 2.50 and 2.45.

The same goes for the KLR650; the shims on the KLR are shim-over-bucket, but 29.0mm not 29.5. CRC also stocks these, since they were used on many vintage Kawasakis. I predict what I'll need next and make sure I'm stocked for the next go-around.

The wee shims found on modern shim-under-bucket systems are much less expensive, and shim kits can be had for a more reasonable sum. The same few shim diameters (7.48mm and 9.48mm are most common) are used on many, many different makes and models.

I already had most of a 7.48mm kit for DL650 V-Stroms; when I bought my FJ-09, I bought a "refill" kit in the usual size range found in the FJ engines to extend the size range on hand and ensure I had enough shims.

And I still have a 9.48mm shim kit used for my DL1000. It hasn't been called into action on another bike yet, but there are quite a few that it fits.