2 Strokes back agian?
 

2 Stroke Clean Smoke
(Wednesday, August 10, 2005)

Here’s a twist flying in the face of the commonly accepted belief 2-strokes are not environmentally clean. BRP, makers of Bombardier ATVs, Ski-Doo snowmobiles, Sea-Doo watercraft and Johnson and Evinrude outboard engines have been awarded the Clean Air Excellence Award from the US Environmental Protection Agency (EPA) this past April.

No, BRP didn’t receive the award for 4-stroke technology but for its Evinrude E-Tec 2-stroke outboard motors. The E-Tec Direct Injection system received the EPA’s coveted endorsement as a result of the system’s ability to achieve carbon monoxide emissions 30 to 50 times lower than a similar 4-stroke outboard. At idle, emissions can be as much as 100 times lower.

Could this signal the return of 2-stroke ATVs? Stay tuned.

2 Strokes back agian?
 

sounds good to me, I'll take mine with 500 cc's single cyl., old school SRA, 27" radials and a torque converter tranny. waiting...tap....tap....tap....[img]i/expressions/face-icon-small-wink.gif[/img]

oh, and a clock too, do they offer one on the '06's?

2 Strokes back agian?
 

I hope they come back again I love 2 stroke power.

2 Strokes back agian?
 

Well dczysd
I’m going to bite on your little fishing trip here!

I have been around a long time and when I look back at the industry I remember when four stroke motocross bikes first showed up all of us said “there’re to heavy , the power to weight ratio is to much , and to many parts” Well now the two stroke motorcycle racer has gone the way of the dinosaur. While the statement we made back then (and I hear now) about P to W and are still true what we didn’t see back then was

1. You have to finish the race to win it! Simple fact is four strokes are more reliable.

2. Four strokes with there wider power band are easier to clutch and gear. This meant a rider who wasn’t as good at controlling shift points and controlling RPM was now equal.

The point I’m making here is all motor sports are technology based and right now you are in the beginning of a change in recreational sport power supply. With the clean air act that will make all the manufactures have to be compliant by 2012, you have seen all the players’ acquire any engine company with either two stroke “clean air technology “or
Lightweight four stroke technology.

Bombardier with their almost total commitment to SDI Evinrude looks like the only company committed to two stroke tech and from what I’m seeing it may prove to be a disaster!
The low emission numbers from their marine engines sound great and at the relatively low RPM range a marine engine runs they work. The reality is the complicated computer maps have resulted in horror stories of broken rings and what can only be described as people running from their product in the snowmobile industry because of the cost of maintenance.

My point here is don’t believe all you read and hear from all the magazines and manufactures! Right now an engine in a pristine environment of a dyno shop may (and I say may) show some low emission numbers, in the real world it hasn’t worked and reliability has suffered greatly.

While four strokes tech has made engines lighter every year and reliability something all of us (especially in the snowmobile world) could only dream of. I think every year you will see these become more and more the dominant player in power for recreational sports.

Watch for Honda to come out with a revolutionary step in the next year!!!

2 Strokes back agian?
 

sounds good to me! we need some reliable technology!

2 Strokes back agian?
 

Huh??? Ah well the 2-stroke E-tec marine engine has NO scheduled maintence for the first 3 YEARS!!!!!!!!! And its backed up by one of the longest warranty's.
All of the new 4-stroke marine engines require a ton a maintence every year!!!!!
Every one else in the marine industry is trying to catch up to BRP now......

2 Strokes back agian?
 

zbart, where did u get all ur facts or should i say assumptions/opinions. i merely posted an article i read. i have a 2 stroke and like it therefore i posted this article.. and your 4 strokes arent getting equal of a 2 stroke just twice as big to match the power of a 2 stroke, if there was a 700cc 2 stroke ?? what next a 1400cc 4 stroke to "catch up".. hehe..

2 Strokes back agian?
 

zbart.. I would tend to agree with you about four strokes being a bit better in durability in some cases. However, BRP has a few different 2 strokes technologies. They have SDI which is semi direct injection in the ski doos, which injects into the transfer ports. Then they have direct injection in the 951 seadoos and the Evinrudes which injects into the cylinder. Both of these technologies are low emission, high fuel mileage engines on dynos and in the field. I suspect that the two strokes will dissappear from the jetskis in the near future. However, the snowmobile guys want light weight and the four strokes have yet to deliver. However, it is probably only a matter of time.
Bryce

BTW.. The Polaris 700 and 900 use similar injection to the BRP SDI. But Polaris adds EGT, so we should see some interesting results from Polaris also.

2 Strokes back agian?
 

Hmmm, well no I don't think they will. They have developed new cleaner two stroke technology.
It's emissions are far less than when compared to a similar model 4 stroke.
It requires less maintenance.
The torque numbers are better, that is the power comes on at much lower RPM's than you would normally see on a 2 stroke.
And 2 stroke engines cost must less to build. Therefor most likely they will incorporate this new technology in there sea doo line as well.

2 Strokes back agian?
 

You need to look at the Seadoo lineup for 2006. The only two stroke left is the 951 DI in the 3-D. All other two strokes are dead. The 951 DI is about 4 years old and used to be the high performance engine. No longer, it is relegated to the 3-D. The 951 DI only good for 130hp. When you compae that to the bottom of the line GTI at 130 hp, the writing is on the wall. The top of the line RXP is 215 HP.
Bryce