When is a 2-stroke supposed to 4-stroke?

C

CaliRebel

New Member

Apr 4, 2011

74

2

0

Santa Barbara, CA

Apr 29, 2011

• #1

I've heard various comments on the board, but I'm unsure when it's a bad sign that it's 4-stroking. Near as I can tell the engine should only be 4-stroking when it's not under load, but some people seem to only get there bike to 2-stroke under full throttle.

When should these bike engines 2-stroke, and when shouldn't they 4-stroke?

 

H

Hammond Egger

New Member

Oct 23, 2010

270

0

0

Tucson, AZ

Apr 29, 2011

• #2

Some people think they should 4 stroke when they are not under a load. I don't think they should ever 4 stroke and if any of mine do I fix it so they don't.

 

bairdco

a guy who makes cool bikes

Aug 18, 2009

6,537

264

63

living the dream in southern california

Apr 29, 2011

• #3

i agree. my bikes never 4 stroke. not uphills, not under load, not at WOT. if they do, something's wrong.

 

C

CaliRebel

New Member

Apr 4, 2011

74

2

0

Santa Barbara, CA

Apr 30, 2011

• #4

Good to know. I imagine it basically just requires a carb adjustment, but what does 4-stroking actually indicate?

 

ToxicAz520

New Member

Mar 11, 2011

288

0

0

Tucson,Arizona

Apr 30, 2011

• #5

Generally 4 stroking indicates that that motor is running rich. My bike after tuning it with jets, better air filter, and opening the intake and exhaust flanges didnt 4 stroke at all.

I just got it tuned (2 weeks ago) and running the best it ever did and then at 20mph the motor siezed and locked up the rear tire, saved it though, thank god I wasn't going faster. Don't know what happened yet but will take the motor apart in a few days and find out.

 

B

Bikeman

New Member

Apr 26, 2011

27

0

0

MS Gulf Coast

May 1, 2011

• #6

I always wondered what exactly would happen when the motor goes. My hand will always be on the clutch lever now.

 

Pilotgeek

New Member

Apr 6, 2011

403

0

0

Green Bay, WI

May 2, 2011

• #7

I have mine tuned to almost never 4-stroke. Only time it ever does is if I'm going down a hill at like 1/4 throttle or less. Any time it's under any load, however small, it runs great. Was just a simple re-jet.

 

camlifter

Active Member

May 4, 2009

1,033

16

36

acme labs marion ohio

May 2, 2011

• #8

never......

 

N

nextpimp

New Member

Mar 28, 2011

22

0

0

NY

May 3, 2011

• #9

Bikeman said:

I always wondered what exactly would happen when the motor goes. My hand will always be on the clutch lever now.

Click to expand...

Buzz .... **CLICK** = CLUTCH!!! Trust me ... Its a LONG 1 1/2 seconds.

 

Al.Fisherman

New Member

Sep 9, 2009

1,966

5

0

Calera, Alabama

May 3, 2011

• #10

Never, not in 5 engines.

 

biknut

Well-Known Member

Sep 28, 2010

6,631

409

83

Dallas

May 3, 2011

• #11

ToxicAz520 said:

Generally 4 stroking indicates that that motor is running rich. My bike after tuning it with jets, better air filter, and opening the intake and exhaust flanges didnt 4 stroke at all.

I just got it tuned (2 weeks ago) and running the best it ever did and then at 20mph the motor siezed and locked up the rear tire, saved it though, thank god I wasn't going faster. Don't know what happened yet but will take the motor apart in a few days and find out.

Click to expand...

What size jet were you running?

 

Skarrd

Member

Oct 13, 2010

501

2

18

34

Chandler, AZ

May 3, 2011

• #12

currently mine only 4 strokes when it's still warming up or at idle. but i feel most of that may have to do with the expansion pipe.