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2021 Doo Release


Turbo Doo

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So, 1 of those things that work great that work great in a clean room/laboratory environment, but not so well in the real world?

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As I understand how it werks, it's basically the same tech as your hybrid car as per starting, but the car uses a battery. 

 

Bombi brings many techs to skidoo's.

Seldom if ever is it "new" tech, just new to skidoos.

 

One good example was the HAC system - new on the '96 Summit I believe. 

This eventually turned into the DPM system by the '99 Zx Summit 600, if not before.

I don't know if it was available on the '99 670 Summit - still in the old chassis or not?

May be more of a Gen 3 motor thing?

 

This was 1910's tech from early airplanes that had a manual adjustment to lean out the carb(s) at higher altitude. 

 

 

Then there was the greased main bearings, which many of us consider a fail, and I believe that the new 850 motor does NOT use grease anymore?

I drilled my cases and cut the seal out of both of ours years ago - after the second time I tied up a crank!

 

 

Not all new ideas that look good on paper work out as well in the field, but no-one will know until you try.

Gotta give'm that!

 

 

.

Edited by Ox
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@Ox I think the RER system had been 'discovered' years ago too. I seem to recall hearing/reading about a sledder trying to start a sled, it back firing & then running backwards.

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2 minutes ago, revrnd said:

@Ox I think the RER system had been 'discovered' years ago too. I seem to recall hearing/reading about a sledder trying to start a sled, it back firing & then running backwards.

Yamaha had it in 2stoke golf carts many moons ago.

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3 minutes ago, gtserider said:

Yamaha had it in 2stoke golf carts many moons ago.

Ahhhhhh

 

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Actually - this subject has come up in recent history on a machine shop site, and running a motor bass akwards roots at least back to the 40's in 4 stroke submarines. 

 

They had to stop the motor and switch to a second set of overhead valvetrain, and restart.

 

These would have been diesel, so not spark editing, but they likely did edit the pump timing a bit?

 

I don't know if/where it was ever used on a 2 stroke before tho, but that is the obvious reason for the end of rotary valving on Doo's.

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15 minutes ago, gtserider said:

Yamaha had it in 2stoke golf carts many moons ago.

If this is true, then how come the others had to licence "RER" from Bombi to use it?

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4 minutes ago, Ox said:

If this is true, then how come the others had to licence "RER" from Bombi to use it?

Good question. Bombi waiting early one morning at the patent office? Yami screw up? I have always wondered and never seen anything written about it.

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11 minutes ago, Ox said:

If this is true, then how come the others had to licence "RER" from Bombi to use it?

Who knows?

 

http://dirtrider.net/forums3/threads/can-2-stroke-engines-run-backwards-ok.157119/

 

I'm guessing the RER came out w/ the ZX sleds in 2000.

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Well, the Zx came out in '99 like I said - with the 600 being the first ser3 motor release, with the 700 in 2000, and the 800 as a 2000.5 I think.

 

RER was available in 2001 at least, but that may have been the first year - as has been mentioned, they likely held that feature to release a cpl years after the new chassis buzz.

 

 

???

 

 

 

I have a '99 Zx Summit 600, with roundslides, and I'm pretty sure that it has DPM, but no RER.

Edited by Ox
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19 minutes ago, Ox said:

Well, the Zx came out in '99 like I said - with the 600 being the first ser3 motor release, with the 700 in 2000, and the 800 as a 2000.5 I think.

 

RER was available in 2001 at least, but that may have been the first year - as has been mentioned, they likely held that feature to release a cpl years after the new chassis buzz.

 

 

???

 

 

 

I have a '99 Zx Summit 600, with roundslides, and I'm pretty sure that it has DPM, but no RER.

I never had reverse on my sleds prior to the ZX. Not sure if I had it on my '01, but definitely on my '04.

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Both of my 2002 800's have it, and I'm pretty sure that it was out the previous season, as I snowchecked mine.

Mechanically - it is just one more pick-up in the mag end of the case to pick up crank timing.

The 'putor does the rest.

Edited by Ox
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3 minutes ago, Oggy said:

I believe Mach z had rer in 1998

My BIL had a Mach 700 triple without RER, but there was a model that did have it.

 

We were stopped at an intersection one day and when he started his sled to get going, he did it in girlly fashion.  Not leaving the seat, he pulled real slow and short.  The engine kicked and started and was running backwards and he didn't know it.  He revved up but the sled didn't move.  He revved up more and I heard the belt spinning around the secondary.  He finally realized what had happened and shut it off and re-started it. After that the sled had a vibration from the melt mark in the secondary pulley.

 

Years latter he did the same thing with my Wildcat, only it pulled the recoil backwards and broke the plastic parts inside.  The rest of the day was clutch wrap starts and I had a recoil to fix.

 

The lesson here is to pull like a man !

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I think you're right.

It does seem like the trippples (reed induction) had RER in the late 90's.

 

You never want to try to finesse the recoil rope in while in electronic reverse!

That's always a bad day!

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1 hour ago, Ox said:

I think you're right.

It does seem like the trippples (reed induction) had RER in the late 90's.

 

You never want to try to finesse the recoil rope in while in electronic reverse!

That's always a bad day!

My buddy had it on a 1999 Mach 1.That was the first one i had seen one with it. I had him open the hood while he hit the button and watched the engine slow down till it almost stalled then kick backward,started running and the rpm picked up. He then hit the button again and it slowed down,almost stalling speed then kicked forward. I was amazed at what i had just seen. Truly a great idea.:right_on:

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4 hours ago, Ox said:

Actually - this subject has come up in recent history on a machine shop site, and running a motor bass akwards roots at least back to the 40's in 4 stroke submarines. 

 

They had to stop the motor and switch to a second set of overhead valvetrain, and restart.

 

These would have been diesel, so not spark editing, but they likely did edit the pump timing a bit?

 

I don't know if/where it was ever used on a 2 stroke before tho, but that is the obvious reason for the end of rotary valving on Doo's.

So talkin about running engines backward    There is a story about Richard Petty's engine ran backwards at Daytona  way way back in the day    His BIL was crew chief   Back in the 70's   was deemed cheating but.... must have made a difference 

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5 hours ago, Ox said:

If this is true, then how come the others had to licence "RER" from Bombi to use it?

   2 strokes have always been able to run backwards. I remember a friends single cylinder Olympic backfiring on startup. When he pressed the throttle to takeoff the sled went backwards putting him over the windshield. My FIL's Club Car had is in the late 70's/early 80's. The golf cart manufacturers did it with a reversing starter motor. A little less sophisticated than Doo's RER. 

  If my memory serves me well, & it usually doesn't, I remember a lawsuit between Polaris & Doo, I think over Doo infringing on Polaris's patented coupled rear suspension. Polaris won & settled for the rights to use RER.

  Feel free to correct me if I'm wrong.

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Kept the radial thrust (?) going the direction they wanted?

 

Did they reverse cut all the gears in the tranny and rear axle then too?

Or maybe just use a center section made for a 4wd front axle?

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7 minutes ago, XTC500 said:

   2 strokes have always been able to run backwards. I remember a friends single cylinder Olympic backfiring on startup. When he pressed the throttle to takeoff the sled went backwards putting him over the windshield. My FIL's Club Car had is in the late 70's/early 80's. The golf cart manufacturers did it with a reversing starter motor. A little less sophisticated than Doo's RER. 

  If my memory serves me well, & it usually doesn't, I remember a lawsuit between Polaris & Doo, I think over Doo infringing on Polaris's patented coupled rear suspension. Polaris won & settled for the rights to use RER.

  Feel free to correct me if I'm wrong.

Yeah, I think you are right - that they did trade features.

That seems to ring a bell.

 

"Always being able to" and being able to efficiently - and on cue is two different things.

You need a secondary timing mark to make it work well.

Edited by Ox
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28 minutes ago, volunteer2 said:

So talkin about running engines backward    There is a story about Richard Petty's engine ran backwards at Daytona  way way back in the day    His BIL was crew chief   Back in the 70's   was deemed cheating but.... must have made a difference 

I believe this is done with twin engine propeller aircraft and stern drive boats.  The engine is assembled with the pistons turned around so the pin offset is the other way and the camshaft is ground mirror image.

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5 hours ago, gtserider said:

Yamaha had it in 2stoke golf carts many moons ago.

"Many Moons Ago"

 

Did that motor actually start fwd and then change direction?

Or just able to start backwards somehow?

 

THAT is likely  the reason Doo had a patent?

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7 minutes ago, Ox said:

"Many Moons Ago"

 

Did that motor actually start fwd and then change direction?

Or just able to start backwards somehow?

 

THAT is likely  the reason Doo had a patent?

Now that you mention it. It could have been the latter.

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Skidoo also gave arctic cat rer .Sea doo used some tech from the tigershark and then gave them rights to rer.

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Back around 1958 to 1960  Mercury Outboards had what they called direct reversing.   Pull back on the remote control and the engine stopped when the handle was upright.   Pull back further and it moved the distributor so when the key was activated the engine started and ran backwards.    This had its challenges.   With no neutral the movement of boat forward loaded the propeller making it harder for the starter to overcome the load.    They also did not have a charging system so the battery was usually marginal.   Thus the term "Mercury Direct Reversing Dock Smasher"

 

 

BZ 

Edited by bzboats
Clarify reverse
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