What is the function of these rubbers

[Korix]

as i was somewhat cleaning out an old engine, i discovered
that the black rubber-ish parts between the fins moved.
i started wondering what their function is. do they need to
remain there ?

 

[bcware]

Vibration damping. I would recommend keeping them, but they can be temporarily removed for cleaning. They vary in size a bit, so don't take all of them out at once or it will be a pain to get them all back in. I made this mistake once. ONCE.

 

[Korix]

alright thanks, sounds like solid reasons to keep em there : )

 

[drewpy]

or soak them in ATF which brings them back to normal

 

[xschris]

Brake fluid work good too.

 

[bcware]

NOW you tell me!

 

[xschris]

So the next time you do it....

 

[moore19ca]

Do they just pop out?

 

[xschris]

Yes they do. I am not sure about dohc bikes tho

 

[willem]

I'm not sure the DOHC bikes have any, I'll check later

Korix has a SOHC though

 

[Tombo]

I was taught in school that it's important to use the rubbers. Good for protection. Against vibration....

 

[Korix]

Korix has a SOHC though

what does that stand for anyway ? i have seen those
2 terms many times when ordering parts. the only difference
i found was it differs in year the bike is from.

 

[Tombo]

SOHC = Single Over Head Cam = one cam shaft works all valves
DOHC = Dual Over Head Cam = different cam shafts for exhausts and intakes

DOHC is a little more complex, little harder for valve adjustments, more modern, and therefore, has some substantial differences versus sohc models - but has more top end power and more horses = faster.