Automatic Transmissions

9/8/2017 4:23pm Edited Date/Time 9/8/2017 4:29pm
Why would that ever be necessary?
Basically the same reason electronic shifting has taken over most other motorsports: because computers can be faster and more accurate than humans.
ns503
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9/8/2017 4:41pm
Hmmm, wonder what ever happened to ol' Bullpen...
Johnny Depp
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9/8/2017 5:04pm
TeamGreen wrote:
I was out practicing on my YZ215 & minding my own business one day when a gentleman pulled up in a truck and unloaded the prettiest...
I was out practicing on my YZ215 & minding my own business one day when a gentleman pulled up in a truck and unloaded the prettiest aluminum tanked all white Husky I'd ever seen...I thought it was the new Husky 500 CR...He said, "It's sorta like a 500CR with no gear box." I was scratching my head. He said,"It's and 'AE' that's been set up for motocross. Would you like to try it?" He didn't have to ask twice...I took it for a little spin and when I came back he said...
"No. Take it for a real ride. Do some laps. Get used to it."
And I did.
It was awesome. It was a special MX version of one of these...the suspension was PERFECT.


The gentleman's name was Dick Burleson.
Cool Story there, I'm sure Burleson's bike was the maximum bomb. I heard that Arlo Englund's mechanic said they could make the transmissions last in MX due to more wide open throttle, but the Enduro team ate up clutch plates often before they could finish an event. I had a friend that had one and we layed out a Vet track on his property in the late 80's and I rode it all the time, I swear I never went faster on anything else and I'll never forget it. Last year that old track got opened as a practice track in Dale TX by his son Clint Wilson. I haven't made it there yet, but I sure will this fall if life get's out of the way.

The Shop

RbR
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9/8/2017 10:49pm


This is the HRC Works CR250 Automatic which won the 1991 All Japan Championship. 4 or 5 speed transmission. HRC ran two full automatic bikes in the series. In addition to the full works bike in the photo, there was one which was much closer to a production bike, which had consistent reliability issues. The full works bike never suffered a failure during the series and was an amazing machine to watch race. Honda had an army of technicians working on both bikes at each race.

Eric Geboers tried the bike in the photo out at the Tokyo Supercross that year and the bike almost killed him and saved his life at the same time. When he hit the big triple the first time, he did a huge endo, like over the bars land upside down kind of endo. As he was rotating and the bike was pointed straight down, he had the throttle pinned wide open in a panic rev, and the bike kept up-shifting through the gears, which reversed the rotation, and he landed on two wheels. Craziest thing I'd ever seen at the track. Geboers parked it after that stunt.





flymoto
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9/9/2017 3:49am
CVT's don't change gears because there are no gears. It's Continuously Variable, hence it's name. You'll never feel gearing changes, ever. Instead, your bike will just...
CVT's don't change gears because there are no gears. It's Continuously Variable, hence it's name. You'll never feel gearing changes, ever. Instead, your bike will just constantly accelerate.

You don't need to worry about downshifting for a corner because the CVT will be in the right spot all the time. Come in to a corner idling speed, roll into it and you'll just pull and pull and pull and pull.
So similar to a electric motor in that respect. That's were the future is, don't know why people arnt more excited to see these things develop like the altas.
9/9/2017 4:32am
91, RC 250. Auto trans, forward kick, Alloy frame.
Proper factory bike. Nothing like today's bling'd up production bikes that we call "factory".



deluxeman
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9/9/2017 5:42am
MotoGP bikes use a sequential gearbox that needs no clutch to shift up or down. Same as F1 and WRC you can still use the clutch if needed but not to shift. I am not sure auto gearbox would even work on a MX bike. Automatics are reactive transmissions, they react after the event starts, go up a hill they downshift when the rpm's drop. Dirt bikes need a proactive gearbox, you anticipate what is ahead and shift up or down or slip the clutch to get through whatever obstacle your facing. I think launch control at the gate would help ( I am sure the factory bikes have something like that already) but later in the race I can't see and automatic helping your lap times. CVT is the same reactive type box. I think the sequential box may be a better option. You would really have to look at lap times and how many .001' of a second you could save. Would it help with rider fatigue and lessen late moto mistakes? It would be interesting to study.

These types of boxes work in roadracing bikes because you shift so many times per lap, and the up and downshifts are more consistent lap after lap. Not sure how much time you could gain in the dirt? Is it really that important? Roadracing your lines stay very consistent and they don't really change throught the race, MX/SX the lines may change every lap on a soft track, so not sure if any box would work better than the one we have now and the human mind running it.
deluxeman
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9/9/2017 5:54am Edited Date/Time 9/9/2017 5:57am
CVT's don't change gears because there are no gears. It's Continuously Variable, hence it's name. You'll never feel gearing changes, ever. Instead, your bike will just...
CVT's don't change gears because there are no gears. It's Continuously Variable, hence it's name. You'll never feel gearing changes, ever. Instead, your bike will just constantly accelerate.

You don't need to worry about downshifting for a corner because the CVT will be in the right spot all the time. Come in to a corner idling speed, roll into it and you'll just pull and pull and pull and pull.
flymoto wrote:
So similar to a electric motor in that respect. That's were the future is, don't know why people arnt more excited to see these things develop...
So similar to a electric motor in that respect. That's were the future is, don't know why people arnt more excited to see these things develop like the altas.
Cause they don't make any noise!!! They don't run on gas and you can't modify them with all kinds of pretty parts. Also look at all the people who suddenly would be out of business. No more Pro Circuit, FMF, Akropovich, Rekluse, Hinson, Bel Ray, all the cylinder head guys all the camshaft and piston guys. You would get to spend all your money on batteries and reostats. On top of all that you would have to listen to what sounds like 40 RC cars racing for 30+2. That would make me want to put a gun in my mouth.

I love internal combustion engines, I love the sound and the smell. When I am at any race track the smell of burning race gas just gives me a certain feeling you can't get anywhere else. Overcooked batteries just don't smell as sweet. Long live dinosaur powerd racing!!!!
Bultaco
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9/9/2017 6:06am
I rode an electric motorcycle for the first time last weekend. It is not an automatic transmission, since there is not transmission......but it is a continuous surge of power from idle to topped out. When electrics are common, this auto-tranny question will not be asked again.

BTW, the sparky-scooter was boring and eye opening at the same time. It is one of our futures.
Bultaco
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9/9/2017 6:15am
Deluxman said: ".....and you can't modify them with all kinds of pretty parts. Also look at all the people who suddenly would be out of business. No more Pro Circuit, FMF, Akropovich, Rekluse, Hinson, Bel Ray, "

Not bashing your statement at all.....however in 1973 Honda released the CR-125 Elsinore. It was so far ahead of anything else available at the time that the magazines and players in the motoworld said the exact same thing. "The 125 Elsinore will put the mod shops out of business because there is nothing to fix on it.". Instead companies like DG, FMF, and host of others were founded making speed parts for the bike that needed nothing.
Monk
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9/9/2017 6:33am
bullpen58 wrote:
But do you think it will ever become a "thing" again? I wonder if they could make an automatic that was race worthy? My guess is...
But do you think it will ever become a "thing" again? I wonder if they could make an automatic that was race worthy? My guess is it would be killer on the start. Maybe have a tranny that is automatic on the start and then magically becomes a standard once it hits 9th gear or whatever?
Airforks became a thing again...
Far-out
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9/9/2017 7:23am
Buy a Ktm sx50, come and ride here in the sand in te Netherlands and you never want a automatic clutch again
TeamGreen
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9/9/2017 7:35am
How long does the battery last on the current crop of electrics (at the track)?

Yesterday I put in 4 sessions (15+ minutes) on an RM-Z 450 using just under 2 gallons of fuel; so, if I do that on an Alta, how do I "keep battery charged" & capable of supplying 100% of it's power for multiple 15-20 sessions w/ ONLY 10 MINUTES BETWEEN SESSIONS? And...What will that cost me?

I love new technology and I ABSOLUTELY LOVE the Silent Running that the Alta provides...&...I REALLY like the people at Alta & the quality of the bike, ESPECIALLY when you realize this is their 1st production bike.

But, I DON'T LIKE:

1. The Price.
2. The lack of ENDURANCE (short battery life/ESPECIALLY on the track).
3. Lack of availability of comparable bikes (competition among manufacturers would change my 1st two items).
Johnny Depp
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9/9/2017 7:59am
Funny how a thread about automatic transmissions turns into an electric bike thread Unsure

If reports are correct, almost everyone who has thrown a leg over an Alta has immediately dropped their best lap times on their own set up bikes by several seconds on the 1st time on a bike not set up for them nor acclimated to the concept of no clutch or shifting.

Automatic transmissions become notable as a possible solution to internal combustion engines to regain that lost advantage.
gsxr6
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9/9/2017 11:44am Edited Date/Time 9/9/2017 4:24pm
Dirt bikes are sequential. One up or one down at a time lol. And u can def shift without the clutch, even on the throttle on a bike with a good trans lol.
Johnny Depp
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9/9/2017 12:19pm Edited Date/Time 9/9/2017 12:20pm
gsxr6 wrote:
Dirt bikes are sequential. One up or one down at a time lol. And u can def shift without the clutch, even on the throttle on...
Dirt bikes are sequential. One up or one down at a time lol. And u can def shift without the clutch, even on the throttle on a bike with a good trans lol.
Of course, but the Yamaha chip controlled shifting system and automatic clutch are new developments in transmission tech by one of the big MX companies.

When you can remove the shifter and clutch from an MX bike then we will have something that could be the next big thing. It's hard to imagine the manufacturer's haven't been more eager to adopt this technology not only for race wins, but for attracting new blood to the sport with a reduced learning curve.
APLMAN99
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9/9/2017 3:44pm
If CVT transmissions were ever installed on dirtbikes, they would destroy the competition.
bullpen58 wrote:
What is a CVT transmission. We're not all NASA physicists here dude.
TeamGreen wrote:
It's the worst thing to happen to the automotive industry. It's the type of transmission in a Prius, for example.
They would be equally horrible for motocross, maybe worse.

For a touring motorcycle like a Gold Wing, they'd probably be great
BobbyM
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9/9/2017 5:48pm
bullpen58 wrote:
Could it ever become a reality in mx?
After losing my shifting leg and then racing again I would start off in 2nd gear shift to 3rd before 1st turn and hole shot
GIwasB4
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9/9/2017 5:51pm
BobbyM wrote:
After losing my shifting leg and then racing again I would start off in 2nd gear shift to 3rd before 1st turn and hole shot
You were counting the gate drop Myersdork! Whats up!!!!!
Eddie_E
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9/10/2017 9:33am
I rented a brand new Sentra with the CVT last year and it had the worst "turbo lag" when you put your foot in it. I'd almost consider buying the car, but the reviews where people mention the belt snapping with no warning don't thrill me.

The technology has worked well in fuel injected Vespa scooters, but removing the variator cover on a scooter is a few simple side cover bolts. I can only assume replacing the variator drive belt on a new car would mean dropping the entire suspension and sub-frame and doing a full 4 wheel alignment when your done. Anybody buying a car or suv should lookup the resale value of a 5~ 7 year old Nissan Murano.
BobbyM
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9/10/2017 11:06am
BobbyM wrote:
After losing my shifting leg and then racing again I would start off in 2nd gear shift to 3rd before 1st turn and hole shot
GIwasB4 wrote:
You were counting the gate drop Myersdork! Whats up!!!!!
Yo bro... KX 500 was awesome. Put it in 3rd and ride the entire track with no issues and no disadvantage anywhere on the track.
9/10/2017 11:17am
StevieD113 wrote:
91, RC 250. Auto trans, forward kick, Alloy frame. Proper factory bike. Nothing like today's bling'd up production bikes that we call "factory". [img]https://p.vitalmx.com/photos/forums/2017/09/09/213881/s1200_96fb1024dd0013db4aed87f690c883c3.jpg[/img]
91, RC 250. Auto trans, forward kick, Alloy frame.
Proper factory bike. Nothing like today's bling'd up production bikes that we call "factory".



I hope you realize their is AMA restrictions as to why they don't make certain modifications like changing the frame or engine cases.
9/10/2017 11:38am
MotoGP bikes have all gone to semi automatic now, it stops the lurch in the chassis between shifts which break traction by loading and unloading the...
MotoGP bikes have all gone to semi automatic now, it stops the lurch in the chassis between shifts which break traction by loading and unloading the suspension.

The manufacturer's are well aware of the benefits, and almost certainly the engineering already exists. There is currently no demand for it, but if you were to have a large performance increase it would change the game.

I'm sure most would insist on a clutch, except if you are a Pro getting beat by an auto you'd have to have it.
They are not semi automatic. They are Seamless transmissions. Much much different.

A seamless gearbox is one that does not go into a neutral between disengaging the first gear pair and engaging the next pair. It engages the next ratio while the current ratio is still driving, and disengages the previous pair before the gearbox can lock up from a double engagement. This means that (1) the engine continues driving the rear wheel at all times during the upshift and (2) the clunk caused by the upshift is reduced to its minimum possible value—just the difference in engine rpm between the two ratios. You can bet that this is further softened by some electronic trickery.
9/10/2017 11:39am
Far-out wrote:
Buy a Ktm sx50, come and ride here in the sand in te Netherlands and you never want a automatic clutch again
Buy a Cobra 50 and you will love it.
9/10/2017 11:40am
deluxeman wrote:
MotoGP bikes use a sequential gearbox that needs no clutch to shift up or down. Same as F1 and WRC you can still use the clutch...
MotoGP bikes use a sequential gearbox that needs no clutch to shift up or down. Same as F1 and WRC you can still use the clutch if needed but not to shift. I am not sure auto gearbox would even work on a MX bike. Automatics are reactive transmissions, they react after the event starts, go up a hill they downshift when the rpm's drop. Dirt bikes need a proactive gearbox, you anticipate what is ahead and shift up or down or slip the clutch to get through whatever obstacle your facing. I think launch control at the gate would help ( I am sure the factory bikes have something like that already) but later in the race I can't see and automatic helping your lap times. CVT is the same reactive type box. I think the sequential box may be a better option. You would really have to look at lap times and how many .001' of a second you could save. Would it help with rider fatigue and lessen late moto mistakes? It would be interesting to study.

These types of boxes work in roadracing bikes because you shift so many times per lap, and the up and downshifts are more consistent lap after lap. Not sure how much time you could gain in the dirt? Is it really that important? Roadracing your lines stay very consistent and they don't really change throught the race, MX/SX the lines may change every lap on a soft track, so not sure if any box would work better than the one we have now and the human mind running it.
You have MotoGP transmissions all wrong. They have seamless gearboxes.

A seamless gearbox is one that does not go into a neutral between disengaging the first gear pair and engaging the next pair. It engages the next ratio while the current ratio is still driving, and disengages the previous pair before the gearbox can lock up from a double engagement. This means that (1) the engine continues driving the rear wheel at all times during the upshift and (2) the clunk caused by the upshift is reduced to its minimum possible value—just the difference in engine rpm between the two ratios. You can bet that this is further softened by some electronic trickery.
Johnny Depp
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9/11/2017 2:25pm
More from the same Cycle World article follows. It's easy to get caught up in how they do it, but what is important is what it does.

" When the seamless gearbox first appeared in 2011 on the factory Hondas, we all reflexively first thought of the time saved by eliminating the neutral between gears. If there are, say, 30 upshifts per lap, and shifter-switch cut-off period is 0.012 seconds, a seamless box ought to give 30 X 0.012 = 0.36 seconds more time when the engine is driving, which in turn ought to improve lap time.

But that’s not what riders perceived. What they perceived was smoother, more confident acceleration off corners, because the size of the upshift clunk was reduced to the minimum possible. In many cases, riders with conventional gearboxes find the upshift so upsetting to the bike in corners that they either short-shift or overrev their engine to move a given upshift to a less upsetting place on the track. Riders talking about this have said the seamless gearbox gives them more options.
The seamless gearbox is also of advantage in improving braking stability (which doesn’t need any great clunks to cope with "


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