Excessive 4-cycling

[canyncarvr]

This thread an off-shoot from a different post.

IC: What is your definition of 'excessive' in this regard?

I noticed last weekend that even at quite high speeds (low loads), ski's bike 2-cycled without missing a beat. Under low loads like that (I mention high speeds because that in and of itself is NOT a classic low load situation..mere wind resistance at speeds of 50/60mph is considerable) my bike 4-cycles a whole lot. I've always liked that, actually. Sounds like a happy 2-smoke to me!

I'm referring not to anything relating to poor throttle response..a loading up that you pay for later. The bike is just skipping along, very happy. ANY time in such instances my bike is running in a complete 2-cycle mode, I'd be looking to fix it!

When I can maintain speeds in excess of 70mph at about 1/4-throttle and still be skipping along...I like that! Touch the throttle and the bike is off like a scairt wabbit!

...found the same to be true of my R5s and RDs, too.

I'm saying I like 'excessive' 4-cycling...I think?

[Colorado Mike]

your bike will go "in excess of 70mph at about 1/4-throttle " ???

Mine is a 220, and with stock gearing hits about 68.5 mph indicated, on a Trailtech compooter. This is at about 4800'. Oh, and with the throttle cable in danger of pulling out of the throttle tube cuz it's being yanked so hard. Sounds like I need one of those super-spoogematic Fredette port jobs.

[IdahoCharley]

CC - I guess it is all very subjective - what is excessive?? Heck I don't know!!

I like to hear some four cycling in classic low load situations i.e. Cruising down a flat fire road at say under 1/2 throttle in 5th or 6th - 4 stroking sound disappears when the bike is slightly loaded with small rise in road same throttle opening. Trail riding situations in second, third, and fourth gears when you are NOT attempting to pick-up speed just maintain a pace I like to hear some four cycling at say under 3/8 throttle opening.

Where I differ (I think) is that above about 1/2 throttle I want the bike to run clean and crisp. Ski's bike likely sounds like mine at speed - not missing a beat unless something is admiss - the way I figure it.

But then again what is excessive four cycling? There are times on the 380 I intentionally turn in the air-screw about 1/2 from ideal so I can get that little hit when riding on fast trails in good dirt. FUN FACTOR. (Of course I'm normally running a gear high because I can't drive the 380 in its power band for long periods of time without getting hurt).

The KDX can be ridden in its power band quite frequently so the air screw is set more to the ideal setting forboth me and the boy. The overal aim is still to set-up the bike to have some 4 stroking sounds some as mentioned above is the classic low load situation.

It all goes back to some sort of a jetting combination which seems to keep the bike happy, keeps the engine's responsive, gives the engine enough fuel so it will pull well under load, but not choke on the fuel: keep the temperatures in check (not too hot (boil overs): not too cold (pipe temperature), keeps the fun factor high. I tell my kids when they ride to keep the "engine happy" i.e. Don't lug it for long periods, stall it out when you should have shifted or scream it to death.

Bottom Line - I still likely have not relayed to you what I believe excessive four stroking is. Too subjective IMO.

[canyncarvr]

CM: I didn't say the track was level.... Actually, the spot I'm thinking of was a tad downsloped. Nothing you could coast down for sure...but not level, either. I have neither a trailtech nor a speedo. I have gps'd my bike to speeds I remember...and of late the engine is spinning a whole lot higher than it did then. Has nothing to do with how fast it goes compared to anything else...just that it goes way-the-hell-too-fast to be riding if you have ANY sense whatsoever. I've had a deer jump in front of me when I was doing <50mph on a road that had a 20-30' DMZ on it. I didn't see a darn thing. Just woke up in the hospital with a broken jaw and fractured head. So....70mph+ on a 'road' that I'm brushing branches with my bars makes sense, 'eh?

re: 'Keep the engine happy.'

Perfectly said!!

On the next Idaho Ride Day we can compare excesses!!

Signed:
Sooper-Spoo

[skipro3]

Idaho Ride Day

Count me in. When do you want us there and send a map.

Oh, I like my eggs over easy. I only told Cindy to fix them scrambled because she is so nice and I didn't want her to worry about breaking any yolks!!

[canyncarvr]

And I only said 'scrambled' cuz YOU did!

Well...not really. Scrambled is just a whole lot easier...

Yup. Gotta be an 'IRD' in the works.

Yanno what, ski...we gotta be invited first. Well...maybe we should just show up!!

WHERE'S THE BEER!!??

...Where'd I put my duck tape....I gotta fix my bike! Listerine for my men, Evans for the steeds!

[clutchcover]

Did I hear Idaho ride day? Gotta be a Southeastern Idaho ride day. The riding is just much better on this side of the state. I'm sure IC will agree. Whenever you fellers feel like making the drive. I'll work my hunting seasons around it, Elk can wait a couple days.
Isn't ski's bike an auto slipper? Does the auto clutch have any effect on the load that is applied to the motor, or it's freewheel effect? Mine runs pretty clean at 1/2 to WOT, but below that it 4 strokes. My bike also spews just a tad and seems happy doing so. I thinks it's like me, I like a little extra food, I'm a tad messy, and I also bog down when I don't get enough to eat.

[skipro3]

clutchcover, that's close enough for an invitation to me. Let us know the best time of year to show up; we'll be there! Get Charley to help with the food and beer tab. Carvr, Wib and m0rie like the pricey stuff. Carvr-Corona (w/a wedge of lime), Wibby-some sort of stout ale stuff that dark and smells funny. Brad will remember the name of it, and m0rie likes St. Paulie Girl. (I really think he just likes the pretty girl with the braided hair on the lable by the way he licks the bottle)

Auto-clutch and effect on the motor load; The way the auto clutch works is that there are a series of ball bearings under the pressure plate. They ride in a ramp; one ball to each ramp. The ramp goes from the inner part of the plate to the outer. When the motor revs up to a certain point; set by a series of washer springs, the balls are forced out and up the ramps by centrifical force. The ramps are tapered so as they climb the ramp and are forced away from the center of the pressure plate, they allow the clutch plates to come into tight contact and off you go!!! As long as the motor is spinning fast enough to overcome the spring washer tension, then the centrifical force will keep the clutch plates in contact. If the motor slows down in rpm, then the ballbearings roll back down their ramps and the plates no longer have a force on them to keep the bike engaged to the rear wheel. This can happen by skidding the rear tire. Lock up the rear tire and the clutch is engaged. Once the clutch is engaged, it won't disengage again until the rpms build up and the balls move up their ramps. A quick fan of the throttle will do it. It works great when on a down hill for example and you lock up the rear wheel. The rear tire will free wheel until the throttle is fanned and the moter is revved up. Then the motor activates the autoclutch and you again have engine braking.
Not enough info? I'll let you ride it for yourself and see what you think. It has me spoiled. Yes, I still know how to use a clutch, but this works perfect every time and I'm getting lazy. It really saved my day this last trip to see Brad. I fell on day 2 and went down hard on my left palm into a stone about the size of a baseball. If I had to work a clutch, I would have crashed even more. As it was, my rear brake is now on a lever where the clutch was, so I got lots of practice using the front brake and saved the rear brake and my hand for emergency stops. I've come to the conclusion that the front brake will work so much better than the rear in any situation and with the right front tire, that I think I'm faster now.
See ya soon!!!

[Indawoods]

I've come to the conclusion that the front brake will work so much better than the rear in any situation and with the right front tire, that I think I'm faster now.

I've said that in several posts. Your front brake has about 10 times the braking effect of the rear. I rarely use the rear brake at all...