Manual disengage for a centrifugal clutch

[The Atomic Ass]

Originally Posted by dcb

Hmm, I wonder what happens if you have an engine brake with a centrifugal clutch? If you can get the engine to stop and if the clutch will still slip a little then the springs should pull the shoes back. Maybe? Break something? Maybe?

I shut the engine down when I decelerate, and the clutch holds very firm until the ~15mph drop-off point.

[dcb]

Well, I was thinking of physically stopping the engine (i.e. add a brake or possibly an early combustion event or something) while rolling and seeing if the clutch would slip and disengage. And if so how smooth would it be. IF that unit is spinning clockwise it might just slip as the housing is overdriven relative to the engine output shaft.

[dcb]

there might be a more logical place disengage in the cvt too, got any exploded diagrams of the bergman tranny?

[The Atomic Ass]

Originally Posted by dcb

there might be a more logical place disengage in the cvt too, got any exploded diagrams of the bergman tranny?

Well, not on the wheel side of the clutch that I can tell.

It won't seem to let me link directly to it, but if you go to Ron Ayers Motorsports, Hover on OEM Parts > Online Microfiche, choose Suzuki scooters then 2006 > Burgman 400,S > Transmission 1 & 2, #2 shows the post-clutch section, 11 being the shaft that the wheel hub is pressed onto, and 1 being the shaft that goes, I believe to the clutch housing. #1 shows the clutch and CVT section.

Jamming the engine is most likely going to cause a momentary rear wheel lock, the clutch does NOT want to slip at all above 15mph.

[dcb]

Ok, I think I get it. This helped too and some googling on variators:

http://www.youtube.com/watch?v=2efLShaZNJg&NR=1

Just thinking out loud,
1. Maybe a longer belt with a spring loaded, lever controlled, idler pully on the bottom? So that you squeeze the lever and it adds a bunch of slack to the belt that the pulleys can't take up completely?

2. integrate a freewheel into the outside of the clutch housing? (bearing on the outside makes it tough).

[Ptero]

This is the Formsprag Clutch Application Manual for Overrunning Clutches.
It will teach you everything you don't already know about sprag clutches and allow you to choose the proper sprag clutch for your application, from bicycles to motorcycles to cars and trucks. It is such an excellent resource that I printed it out, all 52 pages, and mounted it in a 3-ring binder. Then I slobbered all over it. Joy! Oh, joy! It's an ecomodding miracle!

http://www.formsprag.com/litportal/pdfs/P-1052-FCLO.pdf

[The Atomic Ass]

Originally Posted by dcb

Ok, I think I get it. This helped too and some googling on variators:

Just thinking out loud,
1. Maybe a longer belt with a spring loaded, lever controlled, idler pully on the bottom? So that you squeeze the lever and it adds a bunch of slack to the belt that the pulleys can't take up completely?

2. integrate a freewheel into the outside of the clutch housing? (bearing on the outside makes it tough).

1 is right out, I'm afraid. Despite how it looks in the video, the pulley's pull on the belt HARD. The rear pulley is actually fighting the front pulley for gear ratio. Both would snap hard at the belt if it suddenly lost tension. Also, the belt would have to be held disengaged, as the clutch would remain locked up, along with the rear pulley.

2 gives me pause for thought. I can't for the life of me think of a design, but it is possible. Perhaps a video showing the inner workings of a free-wheeling clutch are in order?

Edit: OTOH, Ptero just posted a link that I need to investigate.

[dcb]

Lol, I can imagine ptero closing the drapes and reaching for his 52 page binder now

Heres some half-bakery for ya:
mount another wheel a few inches to the right of the rear wheel, so that it almost touches the ground. When you want to coast just lean the whole bike onto that wheel and coast

[The Atomic Ass]

Originally Posted by dcb

Lol, I can imagine ptero closing the drapes and reaching for his 52 page binder now

Heres some half-bakery for ya:
mount another wheel a few inches to the right of the rear wheel, so that it almost touches the ground. When you want to coast just lean the whole bike onto that wheel and coast

By half-baked I assume you're speaking of yourself?

Your suggestion defies several of the laws of physics to which motorcycles are wont to obey.

[dcb]

Originally Posted by The Atomic Ass

Your suggestion defies several of the laws of physics to which motorcycles are wont to obey.

It does no such thing. You can ride a three wheeler on two wheels, you can ride a 4 wheeler on two wheels. Put training wheels on your bike and balance on one of them to coast (have fun in the corners)