|I have owned a Husaberg 501 and a Honda XR650R that couldn't climb a large sand hill (Devil's Elbow) I could clear with a 25 year old Yamaha YZ465. My younger buddies with their super tuned japanese 450 four strokes can't climb it either! It took my little brother several tries on his 2006 CR250, but he made it over the top! My buddy with his KTM 380 could clear it too. Sand sucks the horsepower out of a bike. A large sandy hill-climb should be a better indicator of horsepower than a dyno test in a magazine! |
|Big bore two strokes need a huge rear tire to turn all them ponies into forward motion. The minimum size should be a 120/100-18 (140mm section width).
If you look close at the pictures in the magazines when they compare a big bore 2 cycle against a new thumper, the 2 cycle bike always has a wimpy or worn out rear tire. Most open class bikes came with undersized tires stock. Why run a 5.10 (110/100-18) width tire on both 250s and 500s? Well friends, the Cheng Shin C760 5.60-18 (see pic) is the tire for big open class two strokes. It has a soft rubber compound and giant knobs that really hook up. You can normally race a whole season with two rear tires. It is big! You can almost fit the biggest Dunlop or Bridgestone inside the C760. The C760 is no longer sold in the USA. You can order them from europe though.
One of my favorite all around MX rear tires is the Pirelli 120/100-18 MT16. I believe it is the same tire as the huge Metzeler MultiCross that came on the big bore Maicos. It really hooks up well and is great in corners. It is the most "under control" rear tire I have ever used for changing track conditions. It last twice as long too! I have used the MT16 rear on everything from the KTM 360 to the Honda CR500 and it has never let me down. Not all 120/100-18 tires are the same! The MT16 is the beast. They just started making the MT16 for 19 inch rim sizes too.
My favorite front tire is the Pirelli MT18 80/100-21 (now called model XCMH)(see pic). The XCMH is a meaty tire and looks bigger than the Japanese fronts. It stays planted on hard or soft terrain and really builds confidence. Guaranteed 70% facplant reduction! It works as well as the Bridgestone M23 on hard pack, and much better than the Dunlop MX51 or D756 for loamy soil. The XCMX is the ultimate tire for changing track conditions. If you have problems with front end wash-out, try the Pirelli XCMH. The MT18 was a favorite of Baja race teams. The Pirelli MT18 is now called the XCMH dual sport DOT enduro tire...but it is the same!
The Metzeler Unicross 90/90-21 is my second favorite front, followed close by the Pirelli MT16 80/100-21. I have used Metzeler MultiCross - Unicross front tires since 1974, and they always gave me a cornering advantage. The Duro HF343 is a cheap front tire that works well on hard pack. Some swear by the Michelin M12 fronts, but I have never used them after my very bad Michelin S12 experience.
Avoid the Shinko brand rear tires for the back of 500cc class bikes. They are very hard. Chunk City!
See All Tires For Sale
|You can normally restore an open class two stroke bike yourself for under $1,000. This includes seals, bearings, and any engine or chassis parts you may need. Restoring a bike you know will be a beast is half the fun of owning one. Restoring a classic car can cost ten times more, but the bike is much more fun. If you can buy an used bike for $2,000, then put another $1,000 into it, it is still a bargain. Try buying a new bike for $3,000 that will give you as much pleasure.|
|I was very blessed growing up in the motorcycle business. My family owned a multi-line dealership, and I worked in the back until I was shipped off to college. I had access to more motorcycles than most people. I normally own 9 or 10 bikes at a time. Most of my family has gone the ATV route. I still can't understand why people give up fast dirt bikes to ride heavy and slow ATVs. If we can understand the switch to ATVs, we can figure out why people are buying four strokes.|
|I have a new project; The Hondaberg. My Husaberg FC 501 engine is toasted. My 1988 CR500R is sitting in the garage with a twisted swingarm and frame (daughter ran over it with her jeep), but a very fresh engine. I think I can build a sub 200 pound fun bike. A Hondaberg 500. This might be better than the CR500AF. The idea sounds cool. I might start when my 84 KTM is done.|
|Best 2 cycle oil? I have tried about every brand looking for that perfect two stroke oil. Motul 800, Amsoil Dominator, PJ1 Goldfire Pro, Golden Spectro, Honda HP2, Yamalube-R, Bel-Ray H1-R, Maxima K2, and Royal Purple are all very good, but getting over priced. |
My favorite is Lucas Semi-Synthetic 2 Cycle Oil. About 4 years ago, a friend of mine that hillclimbs radical KX500 bikes turned me on to Lucas. He said Lucas oil cured his seizing problems he was having.
I run the Lucas Semi Synthetic at 32:1 in everything I own, from my son's high RPM Husqvarna CR 125, to my Gas Gas EC 300. It burns so clean and does not gum-up powervalves. I have noticed there is much less wear too. I normally tear down the Husky 125 every 4 races and replace rings, or piston/rings when running brand "B" oil. With the Lucas Semi-Synthetic 2 cycle, we are on the same rings after 6 races! When I tore it down and checked, everything still looked good. Amazing oil! Now for the good part: Lucas can be purchased at any auto parts store for about 1/2 the price of Motul 800 and it is just as good! Note: Lucas Semi-Synthetic comes with both blue or red lables...but the are exactly the same!
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My 12 Favorite Open Class Bikes
The big bore two stroke is king. There is no way the lies and propaganda from the motorcycle magazines can overcome true facts. So folks, how can the new generation of 4 stroke thumpers beat the big bore ring-ding-dings? They can't! The 4 stroke dyno test results published are ...LIES!
I am an open expert racer from the old days, and have spent plenty of time on the big bore two strokes below. Listed are my favorite bikes and the reasons why. The good news is you can normally find these in good condition at cheap prices if you are willing to travel.
|1. 1983 Husqvarna 500 XC
Ride one and you will see why the 500 XC was the Baja 1000 champion. Your 4 stroke buddies will crash their brains out trying to keep pace. Out of the box, the 500 XC has to be the fastest all around dirt bike. The engine has good low end grunt, brutal mid range, and revs out good on top end. A few other bikes make more horsepower, but none are faster covering ground. The stock gearing gives you a top speed over 100 mph, and it will get there as fast as you can shift gears. The handling is amazing. Yes there are better MX bikes, but for blasting through open country, the XC 500 Husky has no peers. On fast mountain fireroads, You will have KX500s and XR650s eating your dust. Normally you can go several seasons before you need to rebuild the top end. The clutch pull is heavy, but you get use to it. The CR version is fast too, but the XC transmission makes better use of the power. I never did get the chance to try one of the wicked 500cc waterpumpers.
Vintage Husqvarna Club See video of 84 XC500 - ROOST!
|2. 1988 Honda CR500R
This is the most powerful Honda dirt bike ever made. The 1988 CR500 will smoke a 2000 CR500 and blow the doors off the biggest and baddest thumpers. It was faster through the gears than my Maico 490! The power in the mid range is brutal thus making for a lot of fun. The top end power is pretty good too. The Showa front forks are good as they get. In fact these forks work as good as any modern forks. Replace the rear shock with a good aftermarket shock and put on a huge rear tire to get it to hook up. The 1985-1988 CR500s have the same power and scary mid range as the Kawasaki KX 500, but without the pinging problems. I was confident I could win any raced I entered as long as I didn't crash. To race it on a MX track, you cue-ball through the corners and drag race down the straights. You want to scare the crap out of your 4 stroke riding buddies? Let them ride the CR500.
CR500 Riders Forum CR500 Awesome Power Video Clip
Street Tracker & Cafe Bobber Parts - Click Here
|3. 1996 KTM 360 MXC
From corner to corner, I don't think you can get a faster bike. In a 100 yard drag race, the 360 MXC will pull one bike length on my 1984 KTM 495, and two bikes lengths ahead of my friend's rodded Honda CRF 450! The MXC 360 with the Pro Circuit pipe and JD jetting kit is one darn fast dirt bike. The engine must put out at least 55 ponies! The wicked hit in the upper mid range will scare the crap out of you! It has good low end grunt too, and is a blast to trail ride. You can get these bikes cheap used. I just bought mine for $900 a few months ago, and it still had the original sucky Michelins on it. I put on an 80/100-21 Pirelli XCMH (MT18) to make the front end stick. This is the best front tire you can buy. I put a huge Pirelli 120/100-18 MT16 on the back, and it just barely fit. The previous owner already had the Pro Circuit pipe on the bike. The conventional Marzocchi forks and Ohlins shock are completly tunable and are good as any modern suspension. The handling is old school and you feel like you are part of the machine. The engine shares the same lower end as the older 500 KTM bikes, so it should be indestructible! The EXC is pretty much the same, but comes with enduro goodies and wide ratio trans. The SX has the close ratio tranny and 19 inch rear wheel. Update: In a drag race against my buddies KTM 380, he beat my 360 by 1/2 bike length. I am trying to figure out how he cheated.
KTM 360 riders are a diffrent breed - Funny Video
|4. 1981 Husqvarna 430 CR
My 430 CR is quick enough to win races. It is not in the same power league as the CR500 or KTM 495, but it will run neck & neck with a 2006 Honda CR250. The suspension was better than most bikes made in 1981. In fact the suspension is good enough for scrambles racing today against new machines. For high speed desert racing, the handling and stability is difficult to match. It runs good on outdoor MX tracks too. To win on a MX track, you take the high line through the corners and blast down the straights a gear higher than everyone else. With the small 430cc engine, I have pulled many holeshots against bigger bikes, including the hot 450 thumpers. On a nasty rutted fast out outdoor MX track the Husky 430 is king. This is one the the few bikes you can hit the woopies with the throttle wide open! I also like the 430 CR because it looks like a Husky should, plus is is so reliable. I owned it for 28 years and rebuilt the top end twice, replaced one clutch, and had the shocks rebuilt. No other bike I ever owned was made this good. I might rebuid the bottom end this winter just for the heck of it. Of all the bikes I own, the Husky 430 gets ridden the most. I bet the WR and XC versions are cross country speed demons.
Nice Husky 430 CR Pics
|5. 2008 GasGas EC 300
I race motocross in the very competitive vet expert class with the EC300. I never feel I am giving up anything to the 450F or YZ 250 in power and handling. I have even pulled a few holeshots! The EC 300 engine feels more like a four stroke than the new thumpers! The power comes on strong at low RPM and just keeps building and building. This engine has been around since 1999, and is still pretty much unchanged for 2013. The GasGas EC300 has a crazy switch on the handlebars. It has easy to ride big bore power, then you toggle the crazy switch and then all hell breaks loose. 300cc does not sound like much, but the EC300 has more ponies than an uncorked XR650! The EC 300 ride is awesome! It turns and handles a lot like my brother's 2006 Honda CR250, but feels even lighter. The Marzocchi forks and Ohlins rear suspension is top shelf stuff. It feels so comfortable going fast! I have over 25 races on it, and feel it is about time for a new top end. I can see no advantage gained by purchasing a brand new bike. I will keep the 2008 Gasser for a little longer. Bultaco lovers rejoice!
This Video Will Make You Want One - Mudcross!
|6. 1982 KTM 495
The reputation of the KTM 495 as a monster is pretty much right. The engine has decent low end power, strong mid range and insane top end. The powerband is like a ported 250, but twice as strong. It is a good thing the suspension and handling is so good or you could die. The novice will find himself in trouble on this bike. An expert will fall in love. The KTM has one of the best pure racing motors in the open class. The engine does shake and sends vibrations up your spine, but it is built for racing. It you want quiet and smooth buy a KTM 300. KTM has been refining this engine since the Penton Mint 400, so it is hard to break. The KTM 495 is at home on a motocross track or blasting through the desert. The reliability is outstanding. I also spent some time riding a 1989 KTM 500cc water cooled bike. The 500 is crazy fast, but feels heavy and strange when compared to the 495. I am in the process of restoring a 1984 495 and I can't wait to ride it.
Unofficial KTM 495 Site
|7. 1981 Maico 490 Mega
This is the beast! The powerband is wide, but it hits hard down low and builds RPMs in a fraction of a second. A real rocket! Don't pay attention to what the dyno test say. You must ride it! Big sandy hills are no problem. The massive motor and good suspension will have you going faster than you think you are, and you will find yourself overshooting corners. The twin shock 1981 490 was the best handling Maico ever. I don't think there is a bike made that powers out of corners faster! This is a Maico, so check all fasteners often to keep things from falling off your bike. Parts are expensive and getting harder to find. Spend a day on one of the new four strokes, then ride the Maico 490. You will be in for a shock! I swear my arms were longer after each moto. Keep an extra primary chain in your tool box. Sure is a pretty pretty bike. Many say the Maico 440 Mega is a better MX bike, as you get the same great handling with more manageable power.
Vintage Maicos Site
New Maico Bikes Maico 490 in action video
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|8. 2001 KTM 380 SX|
Do you want a bike that handles just like the new nimble 450 thumpers, but has explosive 2 cycle power? This is the bike. It does not feel like a open class bike because of the light weight and nimble handling. Once you crack open the throttle, you will know right away it is not a 250. This bike scoots! With my buddy on the 380 SX, he could pull away from my Husky 430 in a drag race. To get even, I had him follow me through a five mile long nasty sand wash full of woopies and ruts at over 50 MPH. This is where I always run away from hot 450s and 650s on my Husky. I was riding on the edge of life and he was right on my tail the whole time. I was impressed with the off-road performance of such a serious MX bike like the 380 SX. Since the local tracks started letting the big two bangers race, my bud sold his Yamaha 450 after he bought the KTM 380. It is that good! The dyno says the 380 has 56HP, and this is only 2 ponies less than the 2000 Honda CR500! The 380 EXC enduro has the same powerful engine with a wide ratio transmission and lights! The MXC version may be the best all around 380 bike. The older KTM 360 also really rips, and you can find them cheap!
|9. 1983 Honda CR480R
Back when I was racing in 1984, half of the bikes on the starting line were Honda 480 bikes. The powerband on the CR480R is so broad that you could wheelie it in any gear. Each time you would grab the throttle, there would be a nice roost. If you cut down the header pipe section 25mm, it would give you a good boost in top end power. The front forks were pretty good, but the rear suspension had a habit of throwing you off the bike in deep woops. An aftermarket lower link kit fixed the suspension and a Works Performance shock made it great. The 480 used the same chassis as the 250, so the handling was very nimble. Even today, may old timers say the honda CR480 was one of the best. This bike just loved to hillclimb. Also check out the 1984 CR500 with explosive power!
Large Collection of CR480 Pics
|10. 1981 Yamaha YZ465
This was the last model for the Monoshock. Too bad because after 8 years Yamaha got it right! Most of the Yamahop was gone. The stiff rear suspension was fine for riders over 175 pounds. The YZ 465 engine was one of the best open class motors with a sturdy 5 speed transmission. The engine had good mid range power and top end. It was much faster on a MX track than the later YZ490. I could beat my buddy's Suzuki RM500 in a drag race. The handling was very neutral as you could cut corners like a Maico or take the outside line like a Husky. This bike was at home blasting through open country or racing moto-cross. Most 465s sold were used for trail riding. Reliability was top notch and you could normally get two seasons of racing out of the top end. I am amazed how good these bikes still run when neglected for so long. You can find them for under $900 in online classifieds and auctions.
Video - YZ 465 Catches New Thumpers!
Marty Moates on a stock YZ465 beats factory bikes at USGP
|11. 1977 Bultaco Pursang 370
The list would not be complete without an open class speedster from the 1970s. I won more races on the Pursang 370 than any open bike. The powerband was so broad, but plenty fast. It had a strong mid range and love to rev out on top. The Pursang was not the fastest open bike in 1977, but it was the best handling. At 215 pounds, this Bul weighed less than everything else in it's class. You could hit the woops with the throttle pegged and let the bike work under you. You can tell some of the Astro flat-track blood flows through the Pursang, as it corners so well under power. On long fast sweepers, the Pursang had no peers! The 370 Pursang was very reliable. The rings and clutch were good for two seasons. Other than this, all the bike needed was a new rear Metzeler every three races. The 1977 Bultaco Pursang is the cheapest bike on this list to restore, as so many parts are available. The 1976 model was pretty much the same bike.
Jim Pomeroy on 370 Pursang EZ-Jims Team Bull
|12. 1992 Kawasaki KX500
It took Kawasaki 7 years to tune the big KX so it would not ping itself to death. Even with the 1992 KX 500 you still need premium gas and run it a little rich. This is still one of the most powerful open class bikes made. Big sandy hills, no problem! The suspension is only fair and needs some reworking. It corners best with the power on, and with this much power you may find yourself in the bleachers. With a aftermarket rear shock and some front forks tuning, the KX500 is an awesome desert race bike. The Big KX is a brute and is powerful as the 88 Honda CR500. You can always tell novice KX500 owners, as they are always missing the rear fender. I have never ridden one, but the KX500 bikes built after 1996 are suppose to have the suspension sorted out and are just as scary fast.
Nice Picture of 92 KX 500
These are some other big bore 2 stroke bikes I have owned or spent time with.
1979 Husky 390 CR...good handling bike with a wide powerband. I won a lot of races on it. My last year as state champ (1981) was on this bike. Straight line stability was so good, I would do most passing in the woops section! I beat a lot of faster YZ 465s and Maico 440s just because I could stay on the gas in the nasty stuff. I could race a whole season without a top end rebuild!
1991 ATK 406. I wish I could have this one back! This was my favorie trail bike. It had open class power but you could fling it around like a 125. This is an enduro bike that will run with the new 450 thumpers on a tight MX track. The Rotax motor is bulletproof and last about forever. This was the top seller for ATK, so they are easy to find. I am going to get another one soon.
1983 Moto Villa 495 Factory Bike This is the fastest dirt bike I have ever ridden. Villa had some sort of deal working with Carabela. By invitation, I raced one at Mexico City. The motos were 40 minutes of hell, but I won the race! The narrow powerband was like a Suzuki TM400, only with twice the power (think what a ported Maico 490 would be like)! You ride up on the tank, because you never know when the hit is coming. The good handling was just like the Maico 490. I think only a few Moto Villa 495cc bikes were sold in the USA. I wish I could find one.
2002 KTM 300 EXC...power is like a 89 YZ 250 MX bike but has more flywheel and grunt. The 300 EXC is very easy to ride fast. The suspension and handling is very good. Most people don't know KTMs, so you can slap KTM 200 stickers on it and have a real sleeper. My brother did!
1988 Yamaha YZ490 The YZ 490 needs room to get it's legs, so it is not the best choice for MX. High speed stability is very good for the desert. Don't pay attention to the FUD! The YZ490 can win desert races with a little tuning. Don't mess with the head! Raise the exhaust port 4mm, then rejet. The pinging will be gone and it will become a monster! You want a 75HP arm stretcher? Ship the cylinder and head to Eric Gorr with $300. Tell Eric you want it tuned for professional hill climbing or drag racing. Put in some Boyeson reeds, rejet, and add a Pro Circuit Works pipe to finish the job. I wish I had the chance to try the 1992 WR500 with the wide ratio tranny.
1989 KTM 500 MXC...Scary powerful and will smoke the Honda CR500 or Kawasaki KX500. However the KTM 500 did not feel right. The center of gravity was too high. My old KTM 495 was a better bike for me. The 1985-1987 500 KTMs were slower. The 89 & 91 are the real rockets because of input from Danny Magoo Chandler. KTM also made a 550cc torque monster!
1985 Suzuki RM500...It was not a rocket, but had good usable big bore power. The suspension was very good and handled like a 250. In fact a new YZ250 can out run it! A fast 250 rider can win MX with this bike. The 4 speed tranny would have you searching for another gear. The rear suspension was better than any Japanese bike made in 1985. The older RM465 with the 5 speed transmission may be a better choice for all around racing.
2000 Honda CR500 After 12 years of refinement, the handling isn't much better than the 1988 model. In fact, the 88 had better forks! The 2000 has a powerful but friendly powerband while the 1988 makes brutal power. The 2000 CR500 is no doubt the best open classer of 2000. I am dreaming of a Service Honda CR500.
1978 Bultaco 370 Pursang...low end torque, heavy flywheel and wimpy suspension. I let my wife ride it. It was perfect for her 125 pounds (165 lb actual weight). She rode it on trails for several years and just loved it. I always had to start it for her. I would guess the 1978 model used the same engine as the Frontera enduro. The 1974 Bultaco 360 I raced was much faster, and the 1977 370 I owned just flat out hauled butt! The 1976 and 1977 Pursangs were the best handling Bulls, and can be ridden faster than the 78 and 79 models.
1988 CZ 380 Model 514...it would have been a good race bike in 1976. I got it by mail-order. It was a great trail bike as you could not break it. It was one of the most reliable bikes ever owned. The CZ 380 got a lot of use on the ranch. It is an easy bike to hop on and chase cows. Our ranch-hands ride the 25 year old CZ 380 almost every day and can't kill it!
1979 Montesa Cappra 414...handles like a Husky and is scary fast. It had a crazy mid range and a very strong top end. In 1985 I won a local race on it beating out 20 newer bikes. In both motos, I pulled holeshots against expert riders on Maico 490s and KX 500s. I wish I kept it, but parts were impossible to find back in the days before the internet. The quality of the Montesa is amazing. A few years ago I raced an 1975 Montesa Cappra VR 250 that was so fast. I would pull many holeshots against open class bikes! The 250 Montesa has to be one of the best bikes for pre 1978 vintage racing.
1984 Can Am MX 500. Can Am with Armstrong (Jeff Smith world champ) wanted to build the fastest 500 and they had success. Ponies are right up there with the Honda CR500 and KX500. Power is too explosive for for most MX tracks. The bike was heavy and big, so it was a chore to go fast on a motocross track. With a sprocket swap the Can Am MX 500 would pull 120 MPH. Great desert bike! Need parts? Hahhahaha!
1983 Kawasaki KX500...a poor handling brute that pings. I added an extra base gasket to lower the compression and stop the pinging. This dropped the power down to YZ465 range. I never did get the suspension sorted out. With a paddle tire, it was a blast on sand dunes!
1984 Honda CR500...eats OEM piston rings. Wiseco piston & rings fixed it. Handles like the CR480, but the CR500 has better rear suspension. With 60 HP, the mid-range hit is more wicked than a Maico 490! Pings like a KX500 until you get the jetting and fuel sorted out. I tried to ride mine like Danny Magoo and fell down a lot. I learned that only a top pro level racer could win on this bike. I was back on my Husky 430 the next season.
1980 KTM 420. Before the KTM 495, the 420 was the beast. However it did not feel like a beast as you would swear you were on the 250...until you got on the gas. The suspension and handling was so good for 1980. This was one of the few bikes that could compete with the Maico 440 and YZ 465 in shear power. Compared to the older Penton-KTM 400 (really only 354cc), the 420 must make at least 10 more horsepower! Like most KTMs back then, the 420 had above average reliability.
1979 Suzuki RM400 N. This was the best open class bike Suzuki ever built. If you race vintage AHRMA, this is the bike to have if you are looking for cheap upkeep. The RM400 had a real gem of a motor and the handling was very good. This bike had more DeCoster in it than any other RM. Ditto for the 1980 RM400 N. It makes you wonder why Suzuki made the RM465, as the 400 N could be ridden faster.
1977 Maico 440...makes good power and easy to ride fast. One of the fastest bikes in 1977, even though though it felt like an enduro motor. The handling and suspension was way ahead of it's time, and it can compete with the newer bikes. It was so pretty. I could sit in a lawn chair and look at it all day long. This bike loved to hill climb.
1974 Bultaco Pursang 360...The racing bike I turned expert on. At only 207 pounds, It was as close to a factory team race bike as you could get! Going fast was so easy. I switched the Amal for a bigger 38mm Mikuni carb, then advanced the timing a little. I also cut 35mm out of the header pipe. These mods boosted the power into the insane range. My Pursang would outrun anything including the Yamaha Factory Works YZ360! Now for the ultimate AHMRA legal speed trick: You want the power to to hang with the Maico 440 and YZ 465? Swap out the barrel and head for the Astro flat tracker top end. This will make your Bul into a 52HP 10,000 RPM screamer! I owned 14 different Buls and raced them from 1970 until 1980. See Truth About Bultaco Page
1973 CZ 400...It was fast and handled good for such a heavy bike. The holeshot king of 1973! The smoothest big bore engine of them all. The spokes in the wheels were brittle as glass. I learned how to lace wheels because of this bike. If I could put the CZ motor in the Maico frame, I would have the perfect bike.
1971 Suzuki TM400...with it's brutal mid range power, it was the first bike that scared me. After riding my friend's TM 400, I was hooked on open class two bangers.
Fastest Vintage MX Bikes 1971 - 1983 Click Here!
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