Sled engines

It is extremely common for motorcycle engines to have the crank set up as Vance describes, whether boxer or not. My very British Norton parallel twin has the pistons moving in unison but out of phase in the 4 cycle pattern so that only one cylinder fires at a time. On the down stroke, one is intaking while the other is on the power stroke; on the upstroke, one is exhausting while the other is compressing.
This Arctic cat parallel twin sled engine from Suzuki work like you describe

he also have 2 ballancer shaft

 
Hi All

I know to this time that i dont speak too much about my project , because it turn in a slow project

i think some know about life and project and how can thing change

i am in Canada and many of my project parts come from outside of this country

and you know with world stuff in the last 2 year , parts availability , waiting time , shipping , cost

many stuff i buy for my project cost 2 + time what you pay in the USA

anyways i also want to do my engine conversion my own way , to not be painted in a corner with only one gearbox choice

for my pusher engine gyro project i also like a 2 gears gearbox more than a 3 gears , normally less friction heat loss backlash and also help with thrust line vs engine weight

i also want to have my own adapter plate for the 3 cylinder that can work with more than one gearbox and be strong enuff for tractor airplane setup

i also dont want a centrifugal clutch between the crankshaft and the gearbox and no one way bearing sprag

i have for testing a big rubber giubo driveshaft flex coupling like viking 195 and a harmonic fluid damper

you know how an engine conversion developpement can be , parts choice , multiple idea , time , work , money , study , test , new tools needed

in my description i rite dominator conversion , the real thing is i have a dominator single place with a rotax 618 E box

that i want to convert with one of my yam turbo engine , but i change my mind to build a complete new stronger frame with fox suspension shock and 21 inches tires and side by side seating

first i talk to airtrike to put the big SPG 5 gearbox but he cant have a good reduction ratio for me

the SPG 4 is rated 180hp.. and the casting mount is a bit long for my setup

i finally bought an aeromomentum gearbox to try

i study and look at many SAE Engineering paper , and buy 4000+ $ CAD of professional online training formation

on engine calibration to upgrade my knowledge , i am 53 year old , i start riding bike at 11 years old with my first bike a

Yamaha gt 80cc 2 stroke this is the first engine i rebuild , between 1990 and 2000 i work in a small performance harley shop

building chopper bubber and stroker bigbore and full flavor engine build modification

i also build and ride in the past Honda XR 600 bigbore 660 and yamaha yz450f

gyro pilot license here is like private pilot , 45 hours flying time + 40 hours ground school for PPL medical class 3

i am a student pilot with 13 hours in a magni m16 , 1 hour in the DTA , 45 min in a old m24 and a Cavalon

gyro are really cool to fly and be in the air

some ramble.. i am not english , and my brain work faster than my writing skills , many time the english writing is not in the same order than french , or reverse

i want to thank you all for your posting contribution , and the moderator work , and Todd the Administrator for this forum

i am learning with all of you on this Forum
 
Last edited:
The last BMW boxer I worked on fired one cylinder at a time.
While one cylinder reaches top on the compression stroke the other reaches top on the exhaust stroke.

I looked up some BMW engines and specs and the 1100/1200 clearly fire alternately, I could not find anything about firing order for R6, but I think you have to be right about alternate firing order for all of them because if they had ever changed that, it would have been a major development and would be noted in the historical evolution.
I assumed unison firing because our UAV boxer twins all fire unison and the BMW R6 LS I owned was such a thumper that it felt like a single cylinder.....
 
It is extremely common for motorcycle engines to have the crank set up as Vance describes, whether boxer or not. My very British Norton parallel twin has the pistons moving in unison but out of phase in the 4 cycle pattern so that only one cylinder fires at a time. On the down stroke, one is intaking while the other is on the power stroke; on the upstroke, one is exhausting while the other is compressing.
I remember reading that some motorcycle engines use a wasted spark ignition system for simplicity.
 
I remember reading that some motorcycle engines use a wasted spark ignition system for simplicity.

The BMW's do this, at least the older ones.
Doesn't the Rotax 503 do that too?
 
The BMW's do this, at least the older ones.
Doesn't the Rotax 503 do that too?
A two stroke fires every revolution and a four stroke fires every other revolution.

My recollection is a Rotax 503 is a two stroke; so no waste spark for a 503.
 
A two stroke fires every revolution and a four stroke fires every other revolution.

My recollection is a Rotax 503 is a two stroke; so no waste spark for a 503.

Yes, but all plugs fire, so one cylinder is firing at the bottom of the stroke......
 
Yes, but all plugs fire, so one cylinder is firing at the bottom of the stroke......
I have very limited experience with a Rotax 503 so my recollection may be flawed.
Some two strokes do use a waste spark.
 
Hi All

I know to this time that i dont speak too much about my project , because it turn in a slow project

i think some know about life and project and how can thing change

i am in Canada and many of my project parts come from outside of this country

and you know with world stuff in the last 2 year , parts availability , waiting time , shipping , cost

many stuff i buy for my project cost 2 + time what you pay in the USA

anyways i also want to do my engine conversion my own way , to not be painted in a corner with only one gearbox choice

for my pusher engine gyro project i also like a 2 gears gearbox more than a 3 gears , normally less friction heat loss backlash and also help with thrust line vs engine weight

i also want to have my own adapter plate for the 3 cylinder that can work with more than one gearbox and be strong enuff for tractor airplane setup

i also dont want a centrifugal clutch between the crankshaft and the gearbox and no one way bearing sprag

i have for testing a big rubber giubo driveshaft flex coupling like viking 195 and a harmonic fluid damper

you know how an engine conversion developpement can be , parts choice , multiple idea , time , work , money , study , test , new tools needed

in my description i rite dominator conversion , the real thing is i have a dominator single place with a rotax 618 E box

that i want to convert with one of my yam turbo engine , but i change my mind to build a complete new stronger frame with fox suspension shock and 21 inches tires and side by side seating

first i talk to airtrike to put the big SPG 5 gearbox but he cant have a good reduction ratio for me

the SPG 4 is rated 180hp.. and the casting mount is a bit long for my setup

i finally bought an aeromomentum gearbox to try

i study and look at many SAE Engineering paper , and buy 4000+ $ CAD of professional online training formation

on engine calibration to upgrade my knowledge , i am 53 year old , i start riding bike at 11 years old with my first bike a

Yamaha gt 80cc 2 stroke this is the first engine i rebuild , between 1990 and 2000 i work in a small performance harley shop

building chopper bubber and stroker bigbore and full flavor engine build modification

i also build and ride in the past Honda XR 600 bigbore 660 and yamaha yz450f

gyro pilot license here is like private pilot , 45 hours flying time + 40 hours ground school for PPL medical class 3

i am a student pilot with 13 hours in a magni m16 , 1 hour in the DTA , 45 min in a old m24 and a Cavalon

gyro are really cool to fly and be in the air

some ramble.. i am not english , and my brain work faster than my writing skills , many time the english writing is not in the same order than french , or reverse

i want to thank you all for your posting contribution , and the moderator work , and Todd the Administrator for this forum

i am learning with all of you on this Forum

I don't think anyone in gyroplane world knows but the gearbox used by AirTrikes (Vassilli Tarakanov) and by Tango, was first used by me in the US market converting Suzuki engines on trikes back in 2003 to 2005. I put out 10 or 12 Klass trikes with Suzuki engines with SPG-2 gearbox. The later gearboxes were similar, lighter but in my opinion even worst engineering designs. SPG-2 worked well though it was simply overdone and not really engineered for purpose. It is gearbox made in Belarus. I try not to get involved with anything from there any longer
 
A turbo 3 cylinder doing some testing at what can possibly... be higher output power than normal light sport gyro cruise flying

 
Just ... an example... of the new tech available that you cant have just 5 years ago

you dont need this on a turbo gyro motor

it allows to run a big turbo size with better or good result on a motor that you cant in the past

even with rally style fresh air antilag that eliminated lag but not compressor surge

yes we can run gyro motor with all mechanical stuff if we dont want electronic stuff

the best new gyro motor are not all good old school mechanical motor

like Mike new GWS system i think it is a good thing to try to utilize the new tech available

to US for safety

 
Last edited:
I remember reading that some motorcycle engines use a wasted spark ignition system for simplicity.
many car and sled and other type of machine run wasted spark , shure with EFI and turbo i like sequential ignition and injection for the fuel and ignition trim per cylinder

the Harley i work with in the past run wasted spark , in the harley world they call it dual fire

my old stroker run dual fire wasted spark with dyna ignition booster and 2 sparkplug per cylinder with 2 dual tower dyna ignition coil , you can put single fire ignition on it but not really much difference with carburator and normally aspirated

comment from dynojet --- https://dynojet.zendesk.com/hc/en-u...gle-Fire-and-Dual-Fire-What-are-the-benefits-

when i see dual tower with dual sparkplug wire ignition coil it is normally wasted spark , even rotax 912 and the turbo 914 and 915 run dual tower ignition coil wasted spark

and the dual tower coil dont run the 2 sparkplug on the same cylinder , it is part of the redundancy , one tower output on the ignition coil fire one cylinder in the compression stroke the other tower and sparkplug wire of the same coil fire the sparkplug on the exhaust stroke on another cylinder ,

4 stroke cycle 720 deg crankshaft rotation 2 turn , 4 stroke , 4 cylinder divided by 720 deg fire each 180 deg , my Yamaha 3 cylinder 120 degree between crankshaft conrod throw , but 4 stroke 3 cylinder div by 720 = fire each 240 deg

2 stroke fire each 360 deg , rotax 2 stroke 2 cylinder div by 360 fire each 180 deg with one piston before top dead center the other before base dead center wasted spark ,

with 4 sparkplug 2 per cylinder with 2 dual tower wasted spark coil , each coil tower split one per cylinder for redundancy fire one piston BTDC on comp the other BBDC wasted spark , if you put the 2 tower of the same coil on the same cylinder and you lost a coil you run on one cylinder , with each of the 2 coil split on 2 cylinder you lost one coil at high rpm you dont really know

you fall back like a normal 2 stroke 2 cylinder with 2 spark plug or 1 per cylinder

you also have CDI and induction ignition , induction fire a longer spark but need dwell , CDI fire a high voltage shorter duration spark normally with no dwell table coil charge time

the Yamaha 3 cylinder when it first came here on the market in 2005 973cc with carburator

 
In one of my upper post i post the link about the Bosch- Motorsport IMU small sensor

for some that dont know what you can put on a good motorsport grade stand-alone EFI system

Greg Vos have one on his Ducati Panigale for his power management system

you can imagine what a system like this can possibly do on a sled motor conversion to turn a prop




What is a six-axis IMU, and why do high-end bikes have it?​

Let’s take a closer look at this high-tech feature

These days, technology is the name of the game when it comes to performance-oriented motorcycles. Just a decade ago, the notion of having safety features such as ABS on a beginner-friendly motorcycle was reserved for the most premium machines. These days, even affordable scooters like the Yamaha NMAX are outfitted with this safety feature. Naturally, the trickling down of tech features from high-end machines down to mass-market models leaves a lot of room for even more innovation when it comes to bikes in the upper echelons of performance.


Fast-forward to the modern day, and we find motorcycles equipped with technological advancements we could only dream of some ten years ago. Motorcycles like the BMW S 1000 RR feature gyroscopic sensors which unlock a whole host of sophisticated rider aids such as cornering ABS, traction control, and wheelie control. Today, let’s take a closer look at the brain of today’s performance-oriented rider aids, the six-axis inertial measurement unit (IMU), and see just how awesome it has made the modern-day crop of performance machines.

What is it?​


As sophisticated as it seems, an IMU, or inertial measurement unit, is something every single person with a smartphone has already experienced. Those of you who play mobile games that require you to tilt your phone, or, simply swapped between landscape and portrait orientation by rotating your phone have already experienced the benefits of an IMU. From an electronics point of view, an IMU is basically an electronic device which measures a certain object’s position relative to the space surrounding it. To do so, it makes use of a combination of accelerometers, gyroscopes, and sometimes even magnetometers, on ultra complex setups.


When it comes to motorcycles, think of your bike as a giant smartphone. The IMU is able to distinguish the bike’s position across six axes—leftward lean, rightward lean, forward pitch, rearward pitch, leftwar yaw, and rightward yaw. Is your nose bleeding yet? No worries, it’s a lot simpler than you think. So leftward and rightward lean is simple. It’s basically the banking angle of your bike when you’re taking a corner. Forward and rearward pitch are what happens to your bike when abruptly coming to a stop, say, a stoppie; or rapid acceleration, say, a wheelie. Lastly, yaw refers to the oscillation of the bike in relation to the direction it is going (hint: slide control). Now, the IMU’s job is to take note of all this data and send it to the ECU which thereby commands the rider aids to do their respective jobs.

What features does it unlock?​


When it comes to rider aids, a six-axis IMU unlocks a whole host of features which would otherwise be impossible to execute. Simpler, more affordable bikes have rudimentary ABS and traction control systems that make use of nothing but wheel-speed sensors. With an IMU, ABS and traction control can be optimized depending on the behavior of the motorcycle. As such, features like cornering ABS and traction control can be featured on IMU-equipped bikes. The IMU allows the ECU to calculate even finer inputs to the electronic assists, further optimizing their performance.


Other features that can be enhanced by an IMU are fun, performance-oriented aids such as wheelie control, which relies heavily on rearward pitch sensors to determine just how much throttle to cut back as the front end begins to rise. Meanwhile, slide-control, similar to what we find in the Ducati Panigale V4 S, makes use of yaw sensors to keep the bike stable as it gradually slides into a corner. Other nifty features such as cornering lights can also be incorporated into the sophisticated tech web brought about by an IMU. Bikes like the MV Agusta Brutale 1000 even get a fancy full-color display which shows the bikes realtime lean angle.

Why do I need it?​


The answer to the question of whether or not you really need it really depends on the type of riding you’re doing. If you're just riding around town, then naturally, you don’t really need all the sophisticated rider aids made available by an IMU-equipped machine. In the racing environment, however, it’s clear to see where the benefits come in. Most bikes that feature this setup produce close to, if not upwards of 200 horsepower. As such, these safety features keep tabs on all that power, and make an otherwise unrideable machine manageable even to novice and intermediate riders. Of course, you can’t deny how cool it is to know that the bike you’re riding is capable of doing so much more than you, as a rider, are capable of. All these electronic aids on high-power motorcycles not only enhance their overall performance, but increase their level of safety, as well.



 
In one of my upper post i post the link about the Bosch- Motorsport IMU small sensor

for some that dont know what you can put on a good motorsport grade stand-alone EFI system

Greg Vos have one on his Ducati Panigale for his power management system

you can imagine what a system like this can possibly do on a sled motor conversion to turn a prop




What is a six-axis IMU, and why do high-end bikes have it?​

Let’s take a closer look at this high-tech feature

These days, technology is the name of the game when it comes to performance-oriented motorcycles. Just a decade ago, the notion of having safety features such as ABS on a beginner-friendly motorcycle was reserved for the most premium machines. These days, even affordable scooters like the Yamaha NMAX are outfitted with this safety feature. Naturally, the trickling down of tech features from high-end machines down to mass-market models leaves a lot of room for even more innovation when it comes to bikes in the upper echelons of performance.


Fast-forward to the modern day, and we find motorcycles equipped with technological advancements we could only dream of some ten years ago. Motorcycles like the BMW S 1000 RR feature gyroscopic sensors which unlock a whole host of sophisticated rider aids such as cornering ABS, traction control, and wheelie control. Today, let’s take a closer look at the brain of today’s performance-oriented rider aids, the six-axis inertial measurement unit (IMU), and see just how awesome it has made the modern-day crop of performance machines.

What is it?​


As sophisticated as it seems, an IMU, or inertial measurement unit, is something every single person with a smartphone has already experienced. Those of you who play mobile games that require you to tilt your phone, or, simply swapped between landscape and portrait orientation by rotating your phone have already experienced the benefits of an IMU. From an electronics point of view, an IMU is basically an electronic device which measures a certain object’s position relative to the space surrounding it. To do so, it makes use of a combination of accelerometers, gyroscopes, and sometimes even magnetometers, on ultra complex setups.


When it comes to motorcycles, think of your bike as a giant smartphone. The IMU is able to distinguish the bike’s position across six axes—leftward lean, rightward lean, forward pitch, rearward pitch, leftwar yaw, and rightward yaw. Is your nose bleeding yet? No worries, it’s a lot simpler than you think. So leftward and rightward lean is simple. It’s basically the banking angle of your bike when you’re taking a corner. Forward and rearward pitch are what happens to your bike when abruptly coming to a stop, say, a stoppie; or rapid acceleration, say, a wheelie. Lastly, yaw refers to the oscillation of the bike in relation to the direction it is going (hint: slide control). Now, the IMU’s job is to take note of all this data and send it to the ECU which thereby commands the rider aids to do their respective jobs.

What features does it unlock?​


When it comes to rider aids, a six-axis IMU unlocks a whole host of features which would otherwise be impossible to execute. Simpler, more affordable bikes have rudimentary ABS and traction control systems that make use of nothing but wheel-speed sensors. With an IMU, ABS and traction control can be optimized depending on the behavior of the motorcycle. As such, features like cornering ABS and traction control can be featured on IMU-equipped bikes. The IMU allows the ECU to calculate even finer inputs to the electronic assists, further optimizing their performance.


Other features that can be enhanced by an IMU are fun, performance-oriented aids such as wheelie control, which relies heavily on rearward pitch sensors to determine just how much throttle to cut back as the front end begins to rise. Meanwhile, slide-control, similar to what we find in the Ducati Panigale V4 S, makes use of yaw sensors to keep the bike stable as it gradually slides into a corner. Other nifty features such as cornering lights can also be incorporated into the sophisticated tech web brought about by an IMU. Bikes like the MV Agusta Brutale 1000 even get a fancy full-color display which shows the bikes realtime lean angle.

Why do I need it?​


The answer to the question of whether or not you really need it really depends on the type of riding you’re doing. If you're just riding around town, then naturally, you don’t really need all the sophisticated rider aids made available by an IMU-equipped machine. In the racing environment, however, it’s clear to see where the benefits come in. Most bikes that feature this setup produce close to, if not upwards of 200 horsepower. As such, these safety features keep tabs on all that power, and make an otherwise unrideable machine manageable even to novice and intermediate riders. Of course, you can’t deny how cool it is to know that the bike you’re riding is capable of doing so much more than you, as a rider, are capable of. All these electronic aids on high-power motorcycles not only enhance their overall performance, but increase their level of safety, as well.



You had me at Wheelie control. My wheelies suck, and any help I can get with them would be awesome!
 
You had me at Wheelie control. My wheelies suck, and any help I can get with them would be awesome!
The wheelie control in the video is about motorcycle or snow mobile riders who don’t want to flip over backward and don’t have good throttle control.

It is not related to balancing on the mains in a gyroplane.

It just takes practice as there is a lot going on.

I am sure with enough time and money some of the features described could be helpful to flying a gyroplane.
 
What do you think ? of a rotax with remove throttle cable replace by a Bosch electronic throttle body

1660768520339.png
ENGINE
 Dynali Motors 912 ULS-I-BB with injection system & big bore cylinders 1600cc
 Dynali ECU injection system control
 Integrated governor (automatic RPM control)
 SMART Automatic clutch
 Dual fuel pumps
 Electronic throttle body
 Electronic idle control
 RPM limiter
 Simplified engine management
 Optimised power curve
 Adapted and balanced crankshaft
 Double cooled two stage oil radiator
 Cylinder head air cooling system



 
Top