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Where do i find the bypass codes

It is not a motocross bike it is a Enduro

Very cool to see this vid. Thanks for sharing. It brings back a lot of great memories. I purchased a new 73 SC500 in that year and immediately set it up to race District 36 scrambles and short track. I was a member of the Hayward Motorcycle Club, and we put on weekly races every Saturday night during the summer. It was quite a show back then. Many famous riders came through Hayward, and other NorCal tracks, on their way up the ladder. So yeah, I finally felt I was ready, so I scrounged up a 19 inch front wheel and a pair of K70's and off I went. The 500 class was for any motorcycle over 350cc up to 500cc so as you might imagine there were a lot of 360 Yammies (RT's. Not DT's. Get it right people! LOL). So for me the summer of 73 was a blast. Typically Fremont on Friday nights and Hayward on Saturday nights. Did pretty well. Only got one first place that summer though, but had lot's of seconds and thirds and even with those results got to kiss the trophy girl from time to time. Once had what seemed to be another first at Fremont one night. Was in good position to win on the last lap but got too excited on the sweeper leading to the home straight and slid her out. Dang! In regard to how the SC compared to the 360 speed wise, it's hard to tell. The 360 motor was a good one. Very popular, especially among the expert class. Virtually all of those 360's would be in a Champion frame in the 500 expert class. Didn't see one SC500 engine in that class during my time. Nor in the other classes for that matter. I mentioned short track in my opening. I actually only raced short track once. It was in Fremont where they held short track on Wednesday nights. You see, district 36 rules for amateurs had the largest size for the event at 360cc. So you can see where I'm going with this. I was going to be bending the rules a bit (LOL) and enter the event. I figured heck, the same guys I raced with in 500cc scrambles wouldn't mind, plus if look at the primary colors of the 73 SC's and RT's, they are similar. So off we go. I really had a breakthrough that night. I was becoming a better racer. In my heat I got the holeshot. Even though it was first time I raced on the "oval" (I had practiced on it that day) I just seemed to get it. I'm talking about the understanding of how power will keep you in the turn with a higher speed, which without the application of power you would simply slide off the track. So I had it working and it was a blast. My pals in the infield were signaling "hold it back, you got it", but I carried on and won the heat by half a lap. So a little while later we are all assembling for the main. Now I don't know who was the fink, but as I'm checking in at the corral, the official say's "319, you're scratched!" You Bastards, I thought. Didn't you always say how the 500 was a dog. Those finks! So that's my short track career. Man oh man! Oh well, c'est la vie. Back to the motorcycle generally. I thought it was fine. I mean, I was 20 years old, about five ten and a hundred and sixty. I guess I didn't know much better, but I never had any trouble with starting or handling the machine. Yeah, it seized on me a few times. Those big 3.950 inch pistons made for good ashtrays. Had a couple in my garage. Ha! One of the solutions that came from Yamaha for that was to drill like a 1/16 inch hole on the back of the piston just a bit below the rings. Was supposed to allow a bit of premix to get on that surface I guess. So that's my comment and thanks to all. It's cool to see videos by the producers and read all of the comments from the oldtimers and especially the younger guys who appreciate all of these old motorsickles. Take care!

A friend of mine had a late 60's Maico 400 cc two stroke. It too was a "Leg Breaker". Always broke down. Got the nick name "Maico Break O"

My Neighbor had one. I rode it when I was 14 years old.. I had no Issues.. I had a 1974 YZ-80-A with a GYT Kit that tripled my power ..

I have a problem with this tool, it's a KTM 250 2T The tool has not been used for almost a year This week I found time to take care of it, I did a fuel-oil change, I cleaned the filter plug, everything, finally I tried to start it, but the car could not start. It only started with carburetor spray and shut off straight away From that I understood that the carburetor needed to be cleaned and that's how I did it. Now the problem is different, the motorcycle engine goes straight up to very, very high levels I played with the air-fuel screw but unfortunately it didn't help. Is there a situation where the problem is different? Something in the carburetor maybe? need help please

I have a problem with this tool, it's a KTM 250 2T The tool has not been used for almost a year This week I found time to take care of it, I did a fuel-oil change, I cleaned the filter plug, everything, finally I tried to start it, but the car could not start. It only started with carburetor spray and shut off straight away From that I understood that the carburetor needed to be cleaned and that's how I did it. Now the problem is different, the motorcycle drives straight up to very, very high turns I played with the air-fuel screw but unfortunately it didn't help. Is there a situation where the problem is different? Something in the carburetor maybe? need help please

I have a problem with this tool, it's a KTM 250 2T The tool has not been used for almost a year This week I found time to take care of it, I did a fuel-oil change, I cleaned the filter plug, everything, finally I tried to start it, but the car could not start. It only started with carburetor spray and shut off straight away From that I understood that the carburetor needed to be cleaned and that's how I did it. Now the problem is different, the motorcycle drives straight up to very, very high turns I played with the air-fuel screw but unfortunately it didn't help. Is there a situation where the problem is different? Something in the carburetor maybe? need help please

I have a kawasaki kx85 from 2005 i get no spark. I changed spark plug, spark plug boot, ignition coil, stator and wiring. Everything is brand new, I took it to Kawasaki before touching the bike, they said it was the stator that was the problem, I then changed the stator but still no spark and then everything else besides cdi box i can’t find the issue... Is it maybe Cdi box or flywheel magnets?

I ended up with one decades ago on a trade. I sold it without riding it. The new owner said it was terrifyingly fast and ill-handling. He also sold it. In retrospect, I wish I'd kept it.

I grew up in a oil field adjacent neighborhood of single family homes "Getty oil lease" plenty of huge hills, tons of trails. All the kids and families had dirt bikes and rode them on the old field property. 1972-1979, my friends dad had that same 500 Yamaha. On side of the oil lease was a nicer part of the city "Culver City" the other side of the lease was more of a Ghetto neighborhood "Inglewood" YES, LA California. One day my friends parents were out of town so a parked my Kawasaki 90 Enduro and got to ride the 500. My God thought I was dead when flying the bars starting flipping back and forth so fast and out of control, me a skinny 14 year old with 3 years of of motocross experience already weak armed managed to survive before wiping out. Okay, later the day rode it over to the dark side, when some unfriendly ones wanted to ambush me and steal the bike. The only way out was a huge hill trail the ran up under a billboard off the a Blvd with traffic. No body ever attempt this hill not even the adults. At least a 300 foot very rutted trail/hill the last 20/25 feet was vertical if not a little ast 90 degrees at the last 5 feet. This was my only way out with the guys after me. I went for it standing up, cross bar touching my chest, that's how vertical this hill was. My God, I made it. Got back to my friends no one believes this story. I'm 63 years old now 2024 and I still tell people this story. It is TRUE. I never rode that bike again. The best part of the story is my friend snuck his dads bike out. He never found out about it. Great times in my life It's sad kids today will never encounter this type of experience. Society has ruined life for young men. I got to tell you, playing in and around the oil field made me a real man. I'm proud of parents for letting me be a normal kid and giving my brother and sisters and I a great life growing up. My parents struggled through life for us , thank you mom & dad, love you REST IN PEACE

Cool bike dude love it 👍🏻💯

Chem sprayed again.💀🙄🤦‍♂️

That bike was barely ridden.

We need to change the name of proper A/F ratio. I don't know how to say it, spell it and I forget it more than I remember it. I like bob. You are at at bob ratio.

Rode a 76 dt400 for awhile and loved it. I would take the side covers off and race the muscle carsvat the cruise in. I made a lot of money cuz thet thought is was a 250. Dumb asses. Lol.

Those bikes are great hill climbers after you learn how to keep front wheel on the ground

Got a 490....broke my ankle on it...but it is sure alot of fun!

All power and no suspension.

This engine was a beast. If you did some tuning. A better Mike Hair expansion chamber and Dave Barber milling of the piston, it was scary fast. We used a tiny CDI Rotor for the ignition and milled the piston. It had an original problem of the piston exploding because the exhaust was too huge for the size and weight of the piston rocking into the exhaust port. Milling off the top of the of the piston helped a lot.

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I bought a 360 when they came out. It was horrible in every way. It was not a 'leg breaker' so much as a foot and calf bruiser. When starting the kick lever would go down at one point faster than your foot and then come back up on compression and 'smack' It was so bad that mine was an early model and it broke the side case where the kicker extended from and the dealer replaced it with the 'new' reenforced' one Suspension was just awful... which really highlighted the power delivery... Which was abrupt to say the least. the bike had a lot of HP for size but it came on way to abruptly. It was near impossible to do a controlled wheelie. everyone flipped that bike that rode it.

I thought it was the 490 that handled like crap. I raced against 1 in Wyoming the guy was on the ground more than he was on.

Rode a 73 SC500 for 3 years. Great hill climber, big pig on trails and far more horsepower than should have been in that frame. But had lots of fun and people weren't as soft back then. Just like the hot rods we drove. 4 speed big blocks and small block with crappy brakes and crappy suspension, foul plugs, no vacuum, but dam it was fun and would go back in time any day of the week if i could. Freedom to rip and tear is what we had, and the money without Bidenomics to do it. I'd take the crappy bikes and cars.

Cool old big bore. Even cooler is that your Dad bought it new. Don't ever sell it.

The TM 400 has to be a close second as far as dangerous. What kind of boots are those ? I remember Malcom Smith, SIDI and of the ones I had, High Points. I started racing in 79’ at 13 on an IT175 Yamaha, what I’d give to be in 1/2 the shape I was back then, race a 100 miler and man after that was the best shower, dinner and sleep you ever had. I missed a lot of Mondays at school every fall. When I went to a reunion someone said oh yeh you always had a cast or bandage on something lol. If you didn’t ride hard what was the point right.

Had a wickedly built '78 DT400. "0.80 over Wiseco piston, Boyessen reeds, 230 mainjet, with Pod air cleaner and Soundmaster muffler on a stock pipe. 13/38 is stock gears, I had 15/43 tooth sprockets. Oil injection was eliminated for premix, and the compression release valve was disabled. I had a kickstarter from a Yamaha 650 twin steetbike retrofitted on to it. Made the completely insane amounts of compression more manageable. It's shook so violently at idle, it was hilarious. Nobody ever wanted to ride it. The fucker hauled balls.

You guys are so full of it. I’ve had five from original Mx to Champion framed flat tracker, even a road racer. If your timing is spot on , not once did one pop back and hurt me. I did mill off 100thous off the piston flat topped, then shaved the head to bring back the compression . Took off the balance chain junk and my flat tracker was almost too powerful. Yes they are grenades, luckily Vescos is 10 miles north of me. They helped me a lot. Got plenty of trophies with that engine from SC to CA. I grew up in a Yamaha shop with the 175 National Champ. He taught me everything. Forced me to even ride backwards sitting on the handlebars. I miss you Mac McCullough..

You guys are so full of it. I’ve had five from original Mx to Champion framed flat tracker, even a road racer. If your timing is spot on , not once did one pop back and hurt me. I did mill off 100thous off the piston flat topped, then shaved the head to bring back the compression . Took off the balance chain junk and my flat tracker was almost too powerful. Yes they are grenades, luckily Vescos is 10 miles north of me. They helped me a lot. Got plenty of trophies with that engine from SC to CA.

Those early Japanese mx bikes were terrible. My brother had a 1972 Maico 250 and that bike was light-years ahead of

Well I could of told you that would happen

I loved them! If you couldn't start it you were a puss!

Very cool

Lent the 360 MX to a friend who actually was a motorcycle mechanic ... he broke his collarbone on it ... I Bent some "unbendable' handlebars with my leg while going over the bars once .. Still have the scar ..

... I had the same year and model in 360 cc ... That was bad enough .. There's no flywheel so it revs easy and pulls like crazy ... Those shocks I replaced with konis ..it still handled bad .. Turned the shock body into a Pot Pipe using the resivour as the bowl

Stop putting 69 on every old bike-jeez, same old shit

My brother had, most of this is BS, a savy tuner my brother tuned his into a ripper.

My friend raced the silver one and kicked ass with it. I rode it and was impressed with how quick it was. I weighed 120 pounds and had absolutely no issues with starting it. I often had to start my other friend’s bikes for them. Just had to know what you were doing.

I found one on a rural rubbish dump about thirty five years ago From memory it was pretty rough and missing the wheels tank and seat and I mistook it for DT I picked it up and gave it to a fella I knew with a DT thinking it could be useful to him as parts Later the fella's son told me it was a 500 I'd had an RT360 and had mates with DTs but until the young fella pointed out the engine capacity on the barrel of this thing I didn't realise such an animal exsisted

Yamaha XT 500 Kickback leg breaker too .

Yeha if you were a pussey. I roade the 500 and i hade a mx 360 and i never had a problum starting them .they were fast as hell and yeah they wernt for amatures

Those thermal flow shocks are probably the worst shocks ever to come out on a production motocross machine. Yamaha MX's from the early 70' s had nice paint jobs. They look good.

🤩🇺🇸👍⚖️👁️👁️⚖️👍👍🏁🏁🏁🏁

I'm old and remember several mx races in 1973 and 1974 that a good rider on a SC500 won open class events here in the U.S. Ross McLaren won the New Zealand National Championship in 1973, most of the season on a bone stock SC500, only replacing it at the very end of the series with the new YZ. It had the same starting, reliability and tuning issues as every other big bore 2-stroke of the time, nothing more. The SC500's current reputation stems mostly from decades old exaggerated stories told by folks that have either never ridden one or couldn't ride one anyway.

360 was faster

In 1974 I worked in a yamaha shop . I would race a mx 100 175 and the 500 on a given race day.Some of the best times of my life.

Those bikes were badass . Being over 65 and riding the good shit back in the day , I can vouche for them .

Everybody is allways going on about kickbacks. That hasn't been a factor since the advent if the electronig ignition unless it is REALLY mis-timed.