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transmission cover gasket ?

Posted: Sat Sep 05, 2015 2:01 pm
by spaglemon
Had my transmission cover off today for the first time, the thin metal gasket between the cover and crankcase had sort of corroded and bonded itself in various places to both the cover and crankcase, got it off eventually undamaged and have cleaned it up with wd40 and wet and dry paper and it's fine.
Do people put a very thin smear of grease on both sides of the gasket when re fitting ?

Cheers

Re: transmission cover gasket ?

Posted: Sat Sep 05, 2015 3:03 pm
by GeeGusKahn
spaglemon wrote:Had my transmission cover off today for the first time, the thin metal gasket between the cover and crankcase had sort of corroded and bonded itself in various places to both the cover and crankcase, got it off eventually undamaged and have cleaned it up with wd40 and wet and dry paper and it's fine.
Do people put a very thin smear of grease on both sides of the gasket when re fitting ?

Cheers
The gasket on the CVT cover is there to help transfer heat.
Don't use anything on it.
And yes, it helps so it should be reinstalled.
.
Sean

Re: transmission cover gasket ?

Posted: Sat Sep 05, 2015 3:45 pm
by you you
GeeGusKahn wrote:
spaglemon wrote:Had my transmission cover off today for the first time, the thin metal gasket between the cover and crankcase had sort of corroded and bonded itself in various places to both the cover and crankcase, got it off eventually undamaged and have cleaned it up with wd40 and wet and dry paper and it's fine.
Do people put a very thin smear of grease on both sides of the gasket when re fitting ?

Cheers
The gasket on the CVT cover is there to help transfer heat.
Don't use anything on it.
And yes, it helps so it should be reinstalled.
.
Sean

Where does it help transfer heat to and from?

Re: transmission cover gasket ?

Posted: Sat Sep 05, 2015 5:33 pm
by gn2
If the CVT casing was meant to shed heat it would be finned.
I wonder what the fan on the variator does and why there's a hole at the rear of the CVT casing...?

Re: transmission cover gasket ?

Posted: Sun Sep 06, 2015 12:52 am
by spaglemon
So just put it back as is ?

I know many people on here must have that cover off often for tinkering, does anyone else find that the gasket and both mating faces corrode ? perhaps because of the mixture of metals ?

Cheers

Re: transmission cover gasket ?

Posted: Sun Sep 06, 2015 1:09 am
by you you
spaglemon wrote:So just put it back as is ?

I know many people on here must have that cover off often for tinkering, does anyone else find that the gasket and both mating faces corrode ? perhaps because of the mixture of metals ?

Cheers

Personally I'd be tempted to keep it to stop any water ingress and to keep and clearances correct

Re: transmission cover gasket ?

Posted: Sun Sep 06, 2015 3:40 am
by spaglemon
Wasn't thinking of not putting it on, no matter, looks like nobody else has had a similar issue.

Thanks

Re: transmission cover gasket ?

Posted: Sun Sep 06, 2015 5:04 am
by gn2
Grease anywhere near the drivebelt is probably best avoided imo.

Re: transmission cover gasket ?

Posted: Sun Sep 06, 2015 9:25 am
by GeeGusKahn
gn2 wrote:If the CVT casing was meant to shed heat it would be finned.
I wonder what the fan on the variator does and why there's a hole at the rear of the CVT casing...?

Hay gn2
just a thought on -
it would be finned
.
Honda and every other manufacture regardless if auto, scooters, TV's, whatever is looking for ways to cut production costs.
What ever it is that they are making - the price needs to be aimed at the intended market.
.
Rolls Royce, Lamborghini, Ferrari, etc would probably have a finned case because their customer base doesn't even look at the price tag.
Honda as well as others has to look at what the price tag is and what they can do to keep it within the budget of normal folks like us.
.
How many PCX or whatever would sell if the price was $ 5,000 US (or more) or equivalent in pounds or whatever currency you use.
Every step you add to manufacturing process costs money.
Making the case have fins would cost more as even on a cast part such as the CVT cover you would have flashing and other imperfections.
These imperfections would require someone to check each piece, maybe buff it in the fin area or clear the flashing off - price just went up.
The CVT cover on the PCX has the metal gasket to improve the heat transfer from the inner parts to the exterior.
Again, Honda could machine the covers to be a perfect match and no gasket would be required but again - price just went up.
Would fins help - probably yes.
Fins on drive plate are easier to do as piece is probably cast then CNC machined and already requires more attention.
Also because of size and symmetrical shape, easier and quicker to work.
.
Yes, cooling is needed - some design engineer figured that finned drive plate and vent at back of CVT cover would be sufficient or close enough.
.
I have not seen any corrosion on the gasket. I don't think that is an issue unless you live very - very near the ocean or
you live in Buffalo, NY and have heavy salting of roads during the winter.
.
What Honda or any other manufacture does may or may not be the best solution to a problem.
They have to balance cost vs sale ability and the intended target group of consumers.
.
Sean

Re: transmission cover gasket ?

Posted: Sun Sep 06, 2015 11:01 am
by gn2
Heat is transferred to the CVT cover because its unavoidable, not through design.
The heavy lifting of the transmission cooling (including cooling of the casing cover) is done by the fan on the variator.
Have a look at a Forza 300 or a Silverwing 600.
Much more power, much more heat yet the casing has a plastic cover with blanket of foam sandwiched between them.

Re: transmission cover gasket ?

Posted: Sun Sep 06, 2015 2:43 pm
by you you
GeeGusKahn wrote:
gn2 wrote:If the CVT casing was meant to shed heat it would be finned.
I wonder what the fan on the variator does and why there's a hole at the rear of the CVT casing...?

Hay gn2
just a thought on -
it would be finned
.
Honda and every other manufacture regardless if auto, scooters, TV's, whatever is looking for ways to cut production costs.
What ever it is that they are making - the price needs to be aimed at the intended market.
.
Rolls Royce, Lamborghini, Ferrari, etc would probably have a finned case because their customer base doesn't even look at the price tag.
Honda as well as others has to look at what the price tag is and what they can do to keep it within the budget of normal folks like us.
.
How many PCX or whatever would sell if the price was $ 5,000 US (or more) or equivalent in pounds or whatever currency you use.
Every step you add to manufacturing process costs money.
Making the case have fins would cost more as even on a cast part such as the CVT cover you would have flashing and other imperfections.
These imperfections would require someone to check each piece, maybe buff it in the fin area or clear the flashing off - price just went up.
The CVT cover on the PCX has the metal gasket to improve the heat transfer from the inner parts to the exterior.
Again, Honda could machine the covers to be a perfect match and no gasket would be required but again - price just went up.
Would fins help - probably yes.
Fins on drive plate are easier to do as piece is probably cast then CNC machined and already requires more attention.
Also because of size and symmetrical shape, easier and quicker to work.
.
Yes, cooling is needed - some design engineer figured that finned drive plate and vent at back of CVT cover would be sufficient or close enough.
.
I have not seen any corrosion on the gasket. I don't think that is an issue unless you live very - very near the ocean or
you live in Buffalo, NY and have heavy salting of roads during the winter.
.
What Honda or any other manufacture does may or may not be the best solution to a problem.
They have to balance cost vs sale ability and the intended target group of consumers.
.
Sean

Sorry, what is your point.

Re: transmission cover gasket ?

Posted: Mon Sep 07, 2015 5:59 am
by GeeGusKahn
Hay you you
.
If you read my post carefully -
from the beginning -
and the point is not clear
than I apologize for writing gibberish. :cry:
.
Sean

Re: transmission cover gasket ?

Posted: Mon Sep 07, 2015 2:36 pm
by lolofigo
Bollocks. My gasket was corroded and wasn't worth it to put it back after installing Dr pulley sliders. Just put some red silicone gasket and it works a treat. It's 125 tiny engine how much heat does it produce?

Re: transmission cover gasket ?

Posted: Tue Sep 08, 2015 2:47 am
by you you
lolofigo wrote:Bollocks. My gasket was corroded and wasn't worth it to put it back after installing Dr pulley sliders. Just put some red silicone gasket and it works a treat. It's 125 tiny engine how much heat does it produce?

Roughly the same as any other petrol engine