Spinning flywheels?

Message

kdeal · #11 Post by **kdeal** » Wed Dec 12, 2007 2:38 pm

I have heard about all sides of this discussion and I agree that they all cause some problems. The real problem is a design issue more than anything else. The reason the quads spin them easier has to do with the difference in weight of the bikes and the inertia to accelerate & decelerate under load. Remember these are cast aluminum parts with a steel center section casted into them. Considering the majority of these motors are tuned a little hotter than stock and the problem is compounded. BUT, I will still take any and all suggestions to lessen the problem! Now where is my torque wrench?

thedeatons · #12 Post by **thedeatons** » Wed Dec 12, 2007 6:14 pm

Tried it.... still spinning them.... talk to cdsracer about his latest spinning extravaganza.....

kdeal · #13 Post by **kdeal** » Wed Dec 12, 2007 6:23 pm

I was waiting for you to reply! You and your gang have to be the Kings of flywheel spinning.

Canniboomer · #14 Post by **Canniboomer** » Wed Dec 12, 2007 8:16 pm

QUOTE (kdeal @ Dec 12 2007, 10:23 AM) <{POST_SNAPBACK}>

I was waiting for you to reply! You and your gang have to be the Kings of flywheel spinning.

That's why those guys are the ultimate field testers!

For comparisons with dirtbikes, it comes down to 3 things:

Tire slippage
Clutch slippage
Flywheel slippage

Our ATV's have about 5 times the rear axle traction of the dirtbikes,
with more tread width and weight. In a situation where a dirtbike tire will spin, the atv tires will surely bite more.

Clutch slippage?,.... that is rarely a problem with our 'dales. Our clutches tend to transfer all of the force. If we were slipping clutches all the time, then it would actually relieve the forces on the flywheel (nobody wants that!)

Flywheel slippage on the shaft?.... that's only a rare problem, and it seems to always be caused by not having the nut tight enough in the first place. Is that really a problem at 35 ft-lbs of nut torque?... we have not seen the woodruff keys shearing with a correctly tightened nut, or with loctite, or with a new lockwasher or camlock, etc. (check your lockwashers!, some tend to open up about 1/16" when removed, to a larger diameter -- they can become distorted, so please watch then closely -- too soft maybe?)

Flywheel slippage within the Flywheel -- for sure, it's the weakest link, unless the tires spin first!.

SEM designed this flywheel construction back in the 80's . And until Cannondale came along, nobody used it with an ATV. Cannondale started with the MX400 dirtbike, and then one day decided to make an ATV with the same basic motor. Even so, Cannondale did have some problems with spun flywheels on the 432 motor in the MX400, and they DID address that issue with SEM. There was a CDale memo or bulletin about it, to the early dealers. I have it here "somewhere", and will eventually find it again. But of course we all know by now, that even the latest-produced flywheels are still spinning in the ATV's. And it is still quite rare to hear of it happening with the dirtbikes.

cdsracer · #15 Post by **cdsracer** » Thu Dec 13, 2007 3:13 am

I've spun five flyweels on my '02 ATV. This includes the one that was factory installed and lasted several years. After that let go, I haven't been able to get much more than about 200 miles per flywheel. I have installed them with and without my torque wrench set at 35 ft-lbs. No difference, they all come apart.

These things are subject to some incredible forces. In my opinion, aluminum is not a suitable material for this task. What is the availability of the one-piece design?

jesshamner · #16 Post by **jesshamner** » Thu Dec 13, 2007 4:32 am

So how many have you spun cdsracer? It seems like some people have lots of problems and other people have never had a problem. To me, that suggests something to do with the rest of the quad or possibily riding habits/ability intead of the flywheel itself.

I have spun one flywheel. That was the original factory installed 2003 Cannondale Cannibal flywheel. Since then I have not had any problems (knock on wood) and I definitely ride a lot harder now than I did back then.

thedeatons · #17 Post by **thedeatons** » Thu Dec 13, 2007 4:46 am

Cdsracer said he spun five total.... Regardless of the rest of the engine, the flywheel spun, causing the engine to be non-op or "down hard" until being replaced, only to work again as soon as another flywheel was installed. Even if something else WERE wrong with the engine, it has only helped to expose the weakest link, which is obviously the flywheel. Once again, as soon as he puts another flywheel on, it is good to go. The engine is still running, so the flywheel is the weak link we should be addressing.... I ride with him, and every time it is out of nowhere, and he rides like the rest of the group. I can not count the number of times we would have been able to finish a ride had we not spun this crap designed flywheel. (wait, yes I can... five) Boomer said it all when he mentioned "designed in the 80's"...

wayneschofield · #18 Post by **wayneschofield** » Thu Dec 13, 2007 11:08 am

QUOTE (cdsracer @ Dec 13 2007, 03:13 AM) <{POST_SNAPBACK}>

I've spun five flyweels on my '02 ATV. This includes the one that was factory installed and lasted several years. After that let go, I haven't been able to get much more than about 200 miles per flywheel. I have installed them with and without my torque wrench set at 35 ft-lbs. No difference, they all come apart.

These things are subject to some incredible forces. In my opinion, aluminum is not a suitable material for this task. What is the availability of the one-piece design?

I'm pretty sure the Ally in them has just age-hardened and even 'new' ones fail as they are all 'old' having been produced no later than '02. (none I have seen anyway)

I will send you a steel one to test from the next batch I get made. Unless you can convince Tim or C27 to send you the one I sent them for testing......

Sounds like you will be the best person to prove the new design's integrity. Let me have your address via PM.

cdsracer · #19 Post by **cdsracer** » Thu Dec 13, 2007 2:25 pm

Wayne,

I'll be happy to give your flywheel a "spin". PM sent.

Thanks.

jesshamner · #20 Post by **jesshamner** » Thu Dec 13, 2007 3:26 pm

QUOTE (thedeatons @ Dec 12 2007, 11:46 PM) <{POST_SNAPBACK}>

Cdsracer said he spun five total.... Regardless of the rest of the engine, the flywheel spun, causing the engine to be non-op or "down hard" until being replaced, only to work again as soon as another flywheel was installed. Even if something else WERE wrong with the engine, it has only helped to expose the weakest link, which is obviously the flywheel. Once again, as soon as he puts another flywheel on, it is good to go. The engine is still running, so the flywheel is the weak link we should be addressing.... I ride with him, and every time it is out of nowhere, and he rides like the rest of the group. I can not count the number of times we would have been able to finish a ride had we not spun this crap designed flywheel. (wait, yes I can... five) Boomer said it all when he mentioned "designed in the 80's"...

I think you might have missed my point. I was thinking more along the lines of vibration due to too much tolerance somewhere or possibly hot oil. I'm not saying something else is wrong with the motor and that's why the bike shut down. I understand what a spun flywheel will do to a good day of riding. Been there, done that.

If that were the case, saying the flywheel is the weakest link because that is what is failing would be a false positive. It's like saying the oil line from the back of the engine is a weak link because it keeps getting burned by the exhaust. It would work if something else wasn't causing it to fail prematurely. Catch my drift. I will admit that my theory is exactly that...a theory and is in no way based on actual measurements. I just think its weird that some bikes and some riders spin flywheels and other riders on other machines who may ride just as hard don't spin flywheels. There has to be a difference in each setup somewhere....right? I mean, did they just make a bad batch of flywheels? Or maybe Wayne is on to something with the age of the flywheel itself.