Click the Yes button. Click the Skip button if you do not need to configure a second layout. On the “Oops, you’ve lost internet connection” or “Let’s connect you to a network” page, use the Shift + F10 keyboard shortcut. In Command Prompt, type the OOBE\BYPASSNRO command to bypass network requirements on Windows 11 and press Enter. System will reboot and you can select “I don’t have internet” at this step.
King Quad 300 is actually 280cc. Quadrunner 250 is 246cc. Both have the lowest gear ratio ever put in a production ATV in “Super Low” range.
Which one? Quadrunner 250 vs. King Quad 300?
If you have 5-lug nuts on the rear its a King Quad 300. King Quad 300 had a longer stroke, additional clutch plate, oil cooler, slightly longer frame. The Quadrunner 250 came as a 2wd (LT-F250) or 4wd (LT-4WD) versions. The colors and names were used interchangeably depending on the country (e.g. Canada had a blue Quadrunner 300).
Changes through the years…
The 1987 Quadrunner had a one-year only rear u-joint axles which had a different spline count (refer to this thread or the OEM Suzuki repair manual for specifics at the back). 1987 had a one-year-only front and rear racks, square axle nuts, the fan mounts welded on the frame, and silver painted a-arms.
1987-1989, 1990-1999, 2000-2002 carburetor changes. See the carburetor section.
In 1999, the body entirely changed with round headlights along with other minor changes.
Decals changed almost every year. Rear racks changed slightly with a small plate for a “Suzuki” or “Quadrunner” logo.
Refer to the OEM or Cylmer manuals for carb parts breakdown and settings. Do everything possible not to use Amazon carburetors. Use a Shindy rebuild kit and clean the carb. See videos and table. If needed, use eBay and try to afford a used one.
You can buy replacement diaphragms. E.g. for the 31mm carb:
1999: In 1999, it still had the BST31SS (31mm) CV carb with four screws on the top. In 2000, the carb changed to the Mikuni BSR29SS (29mm) CV carb with two screws on the top holding down the needle spring. Good PDF of a forum post of the BST31SS vs. BSR29SS.
Shindy carb rebuild kits are recommended over other brands. See table and purchase on Amazon or eBay.
Always rebuilt the fuel pump. Older units (1987-1989) are easier to access with less fender plastic. ≥1990 can be done but you have to partially remove the fender mud flap. Up through 1998 (square headlights) use this kit and rebuild. You can do this while its still mounted. Unmounting is not fun. Remove the 5 Phillips bolts and rebuild.
Always, ALWAYS leave an air bubble in the sight glass. I cannot overemphasize this enough. ALWAYS leave an air bubble in the sight glass.
Why? Because one fatal flaw of this machine is the vacuum petcock bladder or vacuum fuel pump bladder or the carburetor needle valve fail siphoning gas tank into the crankcase. I have seen this on multiple machines. The gas compromises the oil and you can easily burn the engine up or cause other issues with bottom-end crankcase issues.
Always convert to a manual petcock. See fuel section. Always rebuild the fuel pump. See fuel section. Always turn off the petcock when not in use.
Seeing the bubble in the sight glass is an easy check to verify the oil level has not changed (and has not increased with gas). If the bubble is gone, something needs fixed. Bubble=good. Do not use if you do not see a bubble.
Always use Rotella T6. These things run hot. Especially the Quadrunner 250 with no oil cooler (A small radiator fan is recommended — another topic I will writeup).
17mm bolt and inside you will find a set screw with 12mm lock nut. With your transmission in first gear, break the lock nut loose (to the left). Use a Phillips screwdriver and completely remove the set screw and lock nut. After you removal, take the lock nut off of the set screw, ensuring both move freely.
Once you have separated, put the lock nut back on the set screw just a few threads and reinsert the assembly back into the hole only using your fingers.
Tighten the Phillips screw where you feel it touch/drag on the clutch cage. While holding the set screw with the screw driver use your fingers and snug the lock nut up. Now double check the set screw and make sure it is just barely snug against the plates still, then loosen it about an 1/8 of a turn and use a wrench to slightly tighten the lock nut against the set screw. Do not over torque the nut but make it tight so it does not back off. Replace the 17mm cover nut.
Another issue I have seen on two different used machines I significantly restored (a 1987 LT4WD and a 1994 LT4WDX) is the clutch pack was seized and would never slip correctly. You can test this while riding: if you push and hold down the foot shifter assuming you are in 2nd gear or higher, the machine should coast. On both machines, they would not coast and immediately “flat shift” to the lower gear. This causes unnecessary strain on the shift forks, gears, and overall transmission as the momentarily slipping clutch discs smooth the shift. A more controlled way to test this is to put the machine on a lift or blocks with the rear wheels off the ground and in 2WD. Push and hold the foot shift lever down (going from 2nd into 1st gear) and while still holding the lever down (and NOT in neutral) try to spin the rear tires forward. It will take a little muscle but the rear wheels should move or “free wheel” as the manual clutch pack releases. What is happening internally: the foot shifter linkage releases the spring pressure on the clutch discs allow them to correctly slip. The solution? The clutch discs had seized together. I am not clear why but its a relatively simple fix. Pull the right side cover, reverse threads on the centrifuge clutch, and pull clutch pack and remove all the discs. Inspect discs and coat them in oil before reinstalling each disc. When reinstalling, make sure you properly align the shift fork as the cover is reinstalled and then readjust the clutch as discussed above. Enjoy! Somewhat related: I originally thought it was the one way bearing but is it not. For reference there are two one-way bearings: 1) the starter gear behind the magnets on the left side (this causes the electric starter to slip or for the electric starter to spin all the time quickly wearing it out) and 2) inside the centrifuge clutch cage for engine breaking (this can be checked to make sure the wheels can spin forward in gear without the engine turning over).
Axles & CV joints: Front and Rear
Axles seems to be a an area of confusion as Suzuki used a variety of different u-joints throughout the years. Still documenting more information.
CRITICAL: U-joint must be timed (or phased). In the simplest terms, the inner and outer u-joints must be matched. Refer to the manual for photos. See this video if you are curious on why and to see and hear it: Drive shaft velocity
IMPORTANT: Do not use greaseable U-joints due to inferior strength. There are multiple examples with supporting photos showing immediate failures along with further damage to U-joint yoke(s).
King Quad 300 and QuadRunner 250 complete axles are not interchangeable. However inner/outers possibly can swap.
QuadRunner Front: all interchangeable 1987: used u-joints for inner/outer 1988+: used CV joints for inner/outer. The outer joint can swap to a KQ300.
QuadRunnerRear: not interchangeable 1987: unique inner and outer joints. Splines: 20 and slightly smaller diameter. 1988+: interchangeable. Splines: 22. The inner joint can swap to a KQ300.
Later rear axles included a boot guard (#2) for a rubber boot to protect the u-joint.
Refer to this table I spliced together from Rockford. This is for rear only. I have not found a good reference for the front axles however I believe they are more consistent throughout the years. Please cross-reference this PDF with the specifications on page 2.
The ujoints in my original rear axle were getting pretty worn out. So i decided to replace them. I know the best option is brand new Suzuki axles but at 350$ per side for the inner half and 400$ per side for the outter shaft, i needed tanother option. I found ujoints online listed specifically for the kq. So i went ahead and got some and replaced them. I don’t abuse my bike but after blowing at least 4 joints in a few months last fall after installing the first aftermarket ujoint i figured i needed a better ujoint. I finally found suitable replacement u-joints for the rear axle shaft for the King Quad. So far the GMB brand joints have that held up. In the picture in include side by side comparison of the ones that kept breaking and the GMB and you will see the difference in size. Also one is solid instead of hollow. The only problem is there is no clips to hold them in. The stock one are staked in. So first you have to find a way to get them out. The first one i pressed it out through the stakes and it is some hard to get them out. I also used the 4.5” grinder with a cutting wheel and with my plasma cutter to cut them out. Neither is pretty but you can get them out. Once out you have to file or grind out the stakes. Then you can intall the new ujoints. To hold them in you have to weld them in. I put in a first washer that is smaller than the caps as a shim to center the caps, then i weld in a bigger washer on top of it. I did one shaft last fall and haven’t had any issues yet. So i just did the other one. I might eventually do a third shaft as a spare.
I got my ujoints from Rockauto.com for about 13$ a piece.
For example, the GUT-24 U-joints are an option for ATV404 at 22mm/0.866″ diameter however the overall length or cross span is oversized. See screenshot however I think Alex incorrectly states the 22mm to inches conversation.
87s axles are there own. 88-96 can swap aswell with the king quads. You'll have to find an 87 axle that's good, repair the joint, or swap out the final drive axle aswell as the outers and hubs to use the 88-96 ones.
what I do know for sure is the front inners are for 87s only aswell cause they are ujoints not CVs, my friend with an 88 is always going through boots, so I make fun of him for it.
1990 onwards is interchangeable but 87, 88, 89 are all unique from what I remember. Repair manual is worth it.
There are two different CV diameters changing the cage and rubber boot! Be careful when ordering and check your bell housing ahead of time. If you going to the hassle of doing the inner, do the outer at the same time as its 80% of the work. The inners often fail first. Courtesy of JustRandy:
I spent hours searching online and calling salesmen to finally figure out what someone, somewhere should have said a LONG time ago. 68LAC is 2.5 inches ID and 71LAC is 2.75 inches ID. Now when someone is searching for a CVboot, they can find the info they need.
Just measure the CV bell (the part next to the differential). If its 2.5", you need the 68LAC boot. If its closer to 2.75", you need the 71LAC boot. I have a 1998 and 2001 king quad that measures 2.538" and a 1990 LT4WD that measures 2.720".
Personally, I think either boot would fit either joint. The smaller boot would stretch over the bigger joint and the bigger boot would clamp down on the smaller joint, but they make a big deal out of it when you order boots.
Electrical – CDI 1987-1989 LTWD vs. 1990+ Quadrunner & King Quad 300 Differences
1987-1989 has 7-wire magneto, 7-wire CDI, and voltage regulator 1990+ has the same voltage regulator and magneto. There were different CDI part numbers over the years 1990+ but they have the same pinouts. The CDIs are different between the King Quad 300 and Quadrunner 250. The Quadrunner 250 has a higher rev limit. I have not tried interchanging the CDIs.
1987, 1988, 1989
1990+ QR250 and KQ300
W/L: Ignition Coil L: Goes to Mag (trigger) B/R: Goes to Mag B/W (charge) B: Goes to Mag (trigger common) G: Goes to Mag G/W (charge common) B/Y: Ignition Switch B/W: Ground
W/L: Ignition coil G: Goes to Mag, trigger B/L: Goes to Mag, charge — — O: Ignition Switch B/W: Ground
NOTE: The charge and trigger circuits are isolated AC circuits for 1987-1989. It is unknown if either of the “common” wires are grounded inside the Mag. If, for example, G and B are both grounded, you could use a 1990 CDI and just ignore those wires. This is not known. With both being AC, it is also possible the non-common wires are tied to ground allow 1990+ CDIs. Reference: 89? quad runner 250 2×4 weird spark
FUN NOTE: the CDI triggers every rotation. 1 spark per revolution. As a 4 stroke it sparks every time at TDC and wastes a spark on on the exhaust stroke. Reference: Tach Oddity
Electrical – Voltage Regulator
Common failure: voltage rectifier overcharges causing poor CDI performance and prevents revving up. If your machine runs better (e.g. only revs up) with lights on, its a common failure that you voltage rectifier is failing. Check voltages while running. Idle around 12.7v and 3/4 throttle around 14.5v. If it overshoots and goes upwards of 15v it’s faulty and needs replaced or has a bad ground. The regulator is underneath the front plastics. You need to take your time and remove the front plastics to replace.
NOTE: the regulator is very sensitive to a bad ground. If this ground is not good, the regulator will output a higher voltage “thinking” its outputting the correct voltage. Check this first. A common fix is to splice into the ground wire on the voltage regulator pigtail and crimp a ring terminal and attached to one of the voltage regulator mounting M6 bolts to the frame.
It is common to replace the voltage regulator. I usually replace with an OEM. The 1987-1989 has an additional wire. In studying the 7-wire magneto, I am not clear why the voltage regulator needs an additional wire. I suspect the early voltage regulators use the O/B wire to “enable” preventing battery drain when the key is “off”. If this is the reason, a new voltage regulator should work with issue.
Both the KQ300 and QR250 have different wheel and tire sizes front-to-back with unique hole spacing limiting aftermarket or other wheel options.
IMPORTANT: Do not change tire sizes. The front/back ratio is part of the drivetrain. Larger tires also reduce overall performance due to weight and gearing. Keep the stock sizes. Trust me. I tried it and reverted to original wheels and sizes.
Multiple companies make the same tire in different sizes. Kenda Bear Claw being a popular option. The front differentials are the same between the QR250 and KQ300. The front output shaft gearing is different keeping the ratios correct.
NOTE: the offset is different between the QR250 and KQ300. The KQ300 front wheel will not work on the QR250 without lug spacers.
LT4WD: 3″ difference (22″ front vs. 25″ rear) LT4WDX: 1″ different (24″ front vs. 25″ rear)
QR250 secondary ratio: 1.062 (17/16) KQ300 secondary ratio: 1.125 (18/16) [Different bevel gears. 1 tooth less on KQ300]
OEM TIRE SIZE
LT-250F 2WD, 89-02 (F)
LT-250F 2WD, 89-02 (R)
LT4WD 4WD, 88-02 (F)
LT4WD 4WD, 88-02 (R)
LT4WDX LT-F300F 4WD King Quad, 91-03 (F)
LT4WDX LT-F300F 4WD King Quad, 91-03 (R)
(F) = Front (R) = Rear IS = Independent Suspension SA = Straight Axle
All differentials were the same. The part numbers differ QR250 vs. KQ300 for the bevel gear running the front output shaft. Either its a different ratio for the 1″ vs. 3″ is “close enough” or the ratio is indeed different.
One of the most distinguishing features is the wide range gearing options. From 13.122 in High Ranger, 5th gear to almost 10 times the torque of 126.548 in 1st gear in Super Low range.
Rear Brake With no differential in the rear (both axles connect directly to the final drive gear), there is only one brake on the right side. Most braking is done with the front brakes and rarely does the rear shoes need replaced.
This is where I got my start. Purchased in 1994 for my mother to go back to school. It was promptly torn apart and reassembled many times including tears as I lost important files of her coursework. It did come with stereoscopic 3D glasses.
While old and outdated, this is where I got my start in technology and engineering. It stirred my curiosity at a time when the internet was used less for entertainment. It forced people to understand how-it-works.
Yes, there are benefits of today’s technology requiring only a power button: cellular networks, refined user interfaces, and a 3yo child can be entertained. However ask someone born after the year 2000: “How does the internet work?” or “How does your cell phone work?” or, taking a different angle, “How does your car work?”
Young people have less desire to know how-it-works; partly because it works often without them understanding. One of my goals for our family and children is they develop a passion for learning and understanding how-it-works. Mechanical, electrical, and in life: going deeper in learning about cultures, faith, and that our family values equip them to be firm in their beliefs and in respecting others.
Packard Bell 486 DX2-66 Hardware:
Processor – 486DX2-66
Memory – 8MB
Hard Drive – 840MB
Graphics Chip – 1MB Video
Sound Card – Sound Blaster 16
Optical Drive – 2x CD-ROM
Floppy Drives – 1x 1.44MB 3.5″
Operating System – MS-DOS 6.0/Windows 3.11 for Workgroups
Modem – 28.8Kbps
I vividly recall installing Netscape Navigator and later the Netscape Communicator suite. Communicator included Composer which was an early WYSIWYG editor for creating web pages. It took hours to download Netscape Communicator which I believe was around 15MB.
Click the links; brings back memories! Here were a few Packard Bell included software titles that are remembered fondly:
We all have our favorites: our 1987 Suzuki has been a childhood favorite and with our family since childhood. From the cabin, to the farm, to plowing snow, to pulling trailers, to super-low diff lock — its arguably the most reliable and best ATV ever made. No chains. No belts. Well loved.
A goal is to make this a resource to keep these machines alive. More to come with specific tips, facts, and information specific to the:
LT-4WD 1987-1998 Suzuki QuadRunner 250
LT-F250F 1999-2002 Suzuki QuadRunner 250 – newer body style
LT-F4WDX 1991-1998 Suzuki King Quad 300 [300cc]
LT-F300F 1999-2002 Suzuki King Quad 300 [300cc] – newer body style
“Tackle the tough terrain in four-wheel drive, or switch easily to two-wheel drive using the dash mounted lever and discover what it can really do. The front differential can even be locked when in super low range for extra traction on snow, mud and ice.”
Suzuki lived up to the ads. I purchased NOS brochures and the official Suzuki Service Manual off eBay a few years ago and scanned them in an attempt to preserve history. The ad at the top was the first year: 1987 model pictures. Square axle nut boots (cone shaped all other years ), silver skid plate up front (black all other years), and the only year with the flip up/down front and rear racks. The LT-4WD had a retail price of $3298.00.
Be safe. Stay home. While working longer days now, COVID-19 has given an opportunity to brain dump topics I have been meaning to properly document.
Case-and-point: easy2boot is wonderful. You can boot literally anything off a USB stick. Windows 10 unattended? Yes. Name-your-partition-ISO? Yes. Tivo MFS Tools for hard drive cloning? Yes. Linux flavors? Absolutely. Random PCs that only do BIOS updates via ISO? Yes. And the list goes on… I use it almost daily and support the developer.
In the past few months, easy2boot can now UEFI Secure Boot a Windows 10 Recovery Environment from a FAT32 secondary partition, from there you can swap in an .imgPTN file (now .imgPTN23), reboot, and now load whatever OS you choose from UEFI Secure Boot. Brilliant!
The easy2boot site does a superb job in documenting technical details however that is partly the challenge; its a lot to understand. My use case: an all-power bootable USB stick for Windows installations and WinRE to swap in-and-out different versions. I prefer two identical USB drives for redundancy. Two 64GB USB3.0 all-metal key-chain drives.
Download the latest version (as of writing: Easy2Boot_v2.00A_password_is_e2b.zip)
Make a new USB stick. As of v2.00, “The main change is that when you make a new drive, it will now download the agFM files and copy them to the second FAT32 partition (if present). This allows UEFI-booting to the agFM grub2 File Manager system. All thanks to ‘a1ive’ for developing his grub2 branch and agFM.” Make_E2B.exe and Make_E2B_USB_drive.cmd – downloads agFM if 2nd FAT32 partition is made. If drive is <128Gib then 2nd FAT32 partition of approx 500MB is automatically made.
Because my USB drives are 64GB, I resize (enlarge) the secondary FAT32 partition to ~1.2GB in size to handle the WinRE image [next step].
Add “No key (choose a version to install).xml” to the _ISO\WINDOWS\WIN10\ and _ISO\WINDOWS\WIN7\ directories if not already present. These answer files allow for the “Repair” option.
Copy Win10 ISOs (I always keep a few builds handy; both x86 and x64 combo)
Copy Win7 USB3 ISO (if you have a reason; helpful still for in-place upgrades for activation)
Copy Windows 10 x64 v1909 Injected.imgPTN23. The .imgPTN23 file extension is important. Follow the Adding UEFI/.imgPTN images guide carefully; specifically the “To convert an ISO to .imgPTN file for UEFI-booting” section.
Copy Win10XPE_x64.ISO to the root of your secondary FAT32 partition. This is what you can UEFI boot. You have to make this .ISO file; use Win10PE utility to do it.
Enjoy easy2boot! Its quite wonderful and actively developed. Please support the developer who probably spends a good percentage of their life on this project.
Its been too long. Small engines are a personal hobby; something I can do with our kids and my father. And its an opportunity to learn from “old” technology. I sincerely enjoy understanding the designs of the past; especially when we can’t implement the simplicity today (e.g. due to emissions).
My father picked this up. A first year, all original, one-owner 1971 Suzuki MT50 Trail-Hopper. Has 2665 miles on it. Included is an old Suzuki ad for this fun little machine (courtesy of CollectorsWeekly).
In the process of getting it back running, I could not locate a Service Manual for the MT50 that was freely available. Its important to pay it forward. Here is a scanned copy of a complete Suzuki Service Manual & Part List for Suzuki MT50 TrailHopper 1971, 1972, & 1973. The best section? Reed valves and C.C.I. pages 103-108.
May we take this opportunity to express our appreciation for your continuous efforts in expanding the sales market for our products. At this time we have marketed the Suzuki MT50, which has been made completely new in style and excellent in performance. The Suzuki MT50 has outstanding mechanisms such as reed valve, Suzuki "C.C.I." system and automatic clutch. The engine performance has been improved especially in low speed and climbing ability. And also its top speed registers 48-56 k m/h (30-35 mph). This Service Manual explains, mainly, the principles and construction of these new mechanisms. The most important items, such as disassembling, assembling, tips on adjusting, maintenance standards and tips on handling, are briefly but clearly described in this Manual. By making a practice of using this Manual, it will assist you in performing perfect servicing.