flywheel shield 4 bike-engined car

[LittleLiner]

Car with a bike engine question . . . . . Do I have to come up with a flywheel shield for the bike engine in my coupe build?  Is there something in the rules that exempt this requirement for bike engines in cars?   Seems that if flywheel and clutch explosions were an issue the bike guys would run shields on their bikes.   

Any thoughts, ideas, facts???

[Stan Back]

From what I've read, the car requirements don't ask where the engine came from.  They're equal-opportunity enforceable.

stan

[RichFox]

I asked this question of a well known SCTA offical since I knew that Rick did not have a shield on NT2. He said they were not required as no bike motor had ever blown a flywheel. I pointed out that no Packard had ever blown a flywheel at Bonneville either, but I needed a shield. I was just being a jerk. I have not seen any bike motored cars with flywheel shields and don't believe they are required.

[4-barrel Mike]

http://www.landracing.com/forum/index.php/topic,2357.0.html

You might try a PM to Johnny Hotnuts to get the definitive word on what he has been running and what hoops he had to go thru.

Mike

[wobblywalrus]

Bikes usually have a belt, chain, or gear reduction drive between the engine and the clutch.  This reduces clutch speed.  There are exceptions, such as BMW boxers.  Also, small diameter bike clutches have less centrifugal forces trying to pull them apart than big car clutches, for a given rpm.  That's why bike clutches do not grenade very often.

[Stainless1]

We have only been running a bike motor in a car for 25 years or so.... with that limited experience, we have never been asked to see our clutch shield, we have been asked to show what will keep the chain away from the fuel lines if it breaks, even if they are 2 feet away.  ( yes we have one  ) 

[Jonny Hotnuts]

I called Jim Miller during our pre build. He assured me that a bike motor did not need a secondary shield....something to do with the fact that the casings for bike motors are integral parts of the bike structure and by placement of the engines internal components made it strong enough to contain the components in the event of a primary failure.

I have never been asked about a shield.

However.....

I had a green inspector this year who was in training and sweated me about why I didnt have a chain guard.

I explained to him that the chain was only about 2.5' long and could not reach the driver if it got caught on any rotating component and the fact that I have a firewall thicker than the requirement for the chain guard and was told that I didnt need to have one (when I asked)....still he was not satisfied and it eventually took a senior inspector to pull him to the side and said it was OK, bike engines in cars do not need chain guards. 


ON THAT NOTE:

IF YOUR CHAIN, WHEN AT ITS LONGEST CAN REACH THE DRIVER FROM THE DRIVE SPROCKETS OR OTHER ROTATING ITEM PUT A CHAIN GUARD ON IT OR OTHER COMPONENT TO INSURE IT WILL NOT KILL YOU IF IT GETS CAUGHT ON THE AXLE.

There was a fatality @ Dayton when a chain broke, got caught on the axle and beheaded the driver.

My chain, engine placement and other items in the engine bay make it impossible for the chain to cause driver injury, even in a worst case scenario. I could see installations and placements where I would advise a chain guard.

Good luck and I will be happy to answer any questions you have reguarding the bike to car swaps.

~JH

[Stainless1]

Just be sure the fuel lines are isolated or protected from the chain... the firewall will protect you from the chain but not the fuel tank, pump or lines... protect or locate them so it is not an issue at tech.  Things you have thought about and done something about are usually not issues at tech.
Good luck with your project.