What is "Four-Stroking"?
- Colorado Mike
- Gold Member
- Posts: 1921
- Joined: 11:42 am Feb 25 2005
- Country:
- Location: Colorado
What is "Four-Stroking"?
Okay, I know this will be tough to answer in a written form, but I keep hearing the term "Four Stroking" in the context of jetting the low to mid range of rpm. I don't know what this sounds like. Anybody think they can 'splain it to me?
Thanks,
Thanks,
Mike
Life's tough, it's even tougher if you're stupid.
'04 KDX220
Life's tough, it's even tougher if you're stupid.
'04 KDX220
- skipro3
- Gold Member
- Posts: 4329
- Joined: 11:58 pm Nov 04 2004
- Country:
- Location: BANNED FOR LIFE!!
- Contact:
I'll try:
To experiance 4-stroking, ride your bike at a moderate speed with load on the engine. Back off the throttle just enough to take the load off the engine. As you do so, the motor won't fire clean on every stroke of the piston, but instead, only fire on every other stroke; just like a 4stroke engine does. Open the throttle a bit again, and the 4stroke rattle goes away and a nice clean 2stroke exhaust note will return. If you just chop the thottle closed, the motor will not 4stroke because it has a load on it then too. Just that it is now a load working to slow down the bike, not speed it up.
Hope this helps!
To experiance 4-stroking, ride your bike at a moderate speed with load on the engine. Back off the throttle just enough to take the load off the engine. As you do so, the motor won't fire clean on every stroke of the piston, but instead, only fire on every other stroke; just like a 4stroke engine does. Open the throttle a bit again, and the 4stroke rattle goes away and a nice clean 2stroke exhaust note will return. If you just chop the thottle closed, the motor will not 4stroke because it has a load on it then too. Just that it is now a load working to slow down the bike, not speed it up.
Hope this helps!
Jerry
I'd rather be a smartass like carvr, than a dumbass like.... well, you fill in the blank!
I'd rather be a smartass like carvr, than a dumbass like.... well, you fill in the blank!
- canyncarvr
- Gold Member
- Posts: 6943
- Joined: 01:07 pm Nov 05 2004
- Country: US
- Location: The Mythical State of Jefferson
Yup!
What Ski describes will happen with any 2-stroke, jetted properly or not.
As related to poor jetting you will hear 4-stroking when the engine is loaded up due to excessive fuel...like what most 2-strokes do if you leave the choke on too long. Heck...even if you DON'T leave it on too long the choke/cold/start sequence will usually involve some 4-stroking until the bike 'cleans out'.
It's that blubbering sound...........in any case caused by a 2-stroke NOT firing at every TDC event.
If you're going to be picky...the plug may indeed FIRE..but the mixture will be such that it won't LIGHT.
That warn't tough to 'splain. As long as it's not tough to unnerstan, we're good to go!
What Ski describes will happen with any 2-stroke, jetted properly or not.
As related to poor jetting you will hear 4-stroking when the engine is loaded up due to excessive fuel...like what most 2-strokes do if you leave the choke on too long. Heck...even if you DON'T leave it on too long the choke/cold/start sequence will usually involve some 4-stroking until the bike 'cleans out'.
It's that blubbering sound...........in any case caused by a 2-stroke NOT firing at every TDC event.
If you're going to be picky...the plug may indeed FIRE..but the mixture will be such that it won't LIGHT.
That warn't tough to 'splain. As long as it's not tough to unnerstan, we're good to go!
Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis
bike profile: !clicky!
- Colorado Mike
- Gold Member
- Posts: 1921
- Joined: 11:42 am Feb 25 2005
- Country:
- Location: Colorado
- canyncarvr
- Gold Member
- Posts: 6943
- Joined: 01:07 pm Nov 05 2004
- Country: US
- Location: The Mythical State of Jefferson
'runnin crappy'...'4-stroking'???
Does that apply if it is REALLY a four-stroke?
Does that apply if it is REALLY a four-stroke?
Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis
bike profile: !clicky!
- skipro3
- Gold Member
- Posts: 4329
- Joined: 11:58 pm Nov 04 2004
- Country:
- Location: BANNED FOR LIFE!!
- Contact:
- Colorado Mike
- Gold Member
- Posts: 1921
- Joined: 11:42 am Feb 25 2005
- Country:
- Location: Colorado
uh, yeah, I think that fits. BTW, of the four guys I ride with most often, I'm the only 2 stroker left. Which means my bike takes about 40 times less kickstarts per day of riding than the next leading competitor. These guys get pissed when they see mine start on one kick from stone cold. And the guy on the YZ426 can work himself into heart attack country trying to kick it over after he dumps it. I think I'll work on starting it with my hand just to watch the tops of their heads blow off...
Mike
Life's tough, it's even tougher if you're stupid.
'04 KDX220
Life's tough, it's even tougher if you're stupid.
'04 KDX220
- KDXGarage
- KDXRider.net
- Posts: 14063
- Joined: 06:45 am Nov 01 2004
- Country: United States of America
- Location: AL, USA
- Contact:
I like to watch the SX and MX races and when the four stroke racers tip over and stall it, I love to scream, "KICK IT, YOU SOB!" at the screen.
Be sure to give 'er a little gas with one hand when cranking it with the other. That would kill them.
Be sure to give 'er a little gas with one hand when cranking it with the other. That would kill them.
Thank you for participating on kdxrider.net.
To post pictures from a device: viewtopic.php?f=88&t=24128
To post pictures from a device: viewtopic.php?f=88&t=24128
- jackpiner57
- Supporting Member I
- Posts: 88
- Joined: 05:05 pm Apr 16 2005
- Country:
- Location: Vermont, USA
Please try to get it on video! I will pay you good money for a copy
2002 KDX200
2005 KX85
2005 DL650K5 V-Strom
NETRA
AMA
Montshire Trail Riders
Vermont Motocross Association
I got stopped for speeding and the cop asks me "Don't you know the speed limit is 55 miles per hour?" So I said "yeah but I wasn't gonna be out that long."
2005 KX85
2005 DL650K5 V-Strom
NETRA
AMA
Montshire Trail Riders
Vermont Motocross Association
I got stopped for speeding and the cop asks me "Don't you know the speed limit is 55 miles per hour?" So I said "yeah but I wasn't gonna be out that long."