CMF Rubber plug

[G Ellis]

Want to know what is the real purpose for the large rubber plug above the air box?

[firstturn]

Besides keeping water out it does restrict air flow.....

Ron Carbaugh

[G Ellis]

Uncle Ron thanks. But why put it there in the first place? Why not just cover it with metal. And not form a big hole. It already has a back bone breather frame.

[firstturn]

Possibly costs too much to change the frame design after it was done originally and back then those changes costs money and manufacturers had to watch costs.  I know at Honda a change that cost $0.25 had to be justified.

Ron Carbaugh

[skiracer]

I asked the same question a couple of years ago...  I was then told that the hole was to get extra air to the motor for motocross.  Since the bike was running at higher RPM's, the additional air flow helped the motor.......

1976 MC 5 Original Owner
1982 Suzuki PE 175
1976 Penton 175 XC
1985 20' Hi Point trailer

[Lew Mayer]

It was there to keep the air intake high for enduros and water crossings but you could remove it for MX.

Lew Mayer

[Paul Danik]

I have done a bit of searching for anything written in any Penton manuals or advertising materials stating that the rubber plug can/should be removed for improved breathing for MX and have yet to find anything. Possibly one of you know of something in print? Just curious.....

Thanks
Paul