vent holes in transmission case

[04vinoguy]

I just put some holes in my transmission case, hope this will keep it a bit cooler.. Picture of holes here.. (http://i8.tinypic.com/6bumw6b.jpg)

[harry]

i'd worry about dirt or sand getting in the clutch
or messing up the belt
most bigger scoots have a large vent hole with a baffle on the top of the case sort of like a scoop.

oilyhans

[str8dum]

do u feel air puling and blowing out those holes? if not, then its not doin anything

[burnt_toast]

Looks good, similar to my cooling pattern on my zip. And you can test if it blows through by blowing air from one side and feeling it with your hand on the other. Too small a hole, you won't feel anything, but yours look just as big as mine so should be cooling atleast better than stock.

[OldGuy1]

Ok, never thought this was a good idea so finally did some research. Looked at lots of pictures of full-bore racing scooters from around the world. Guess what? None of them seem to have holes drilled in the transmission case!

Seems to me if anyone was going to have transmission cooling problems it'd be them.

Of course, if anyone can find an image or a suggestion by a real, certifiable racer I'm willing to be swayed. Until than my transmission cover remains as Yamaha designed it.

[burnt_toast]

Ok, never thought this was a good idea so finally did some research. Looked at lots of pictures of full-bore racing scooters from around the world. Guess what? None of them seem to have holes drilled in the transmission case!

Seems to me if anyone was going to have transmission cooling problems it'd be them.

Of course, if anyone can find an image or a suggestion by a real, certifiable racer I'm willing to be swayed. Until than my transmission cover remains as Yamaha designed it.

Uhm, I'm sure they have some form of cooling their transmission. Especially if they're cast big bores, the trans will run very very hot. This has been done plenty by others. My 90cc cast zip runs at 200-300deg F temps, and the trans could use all the cooling it can get.

Here's some previous threads:
http://www.provoscooter.com/vbull/showthread.php?t=2968
read post#4 for an explanation

another good thread:
http://www.provoscooter.com/vbull/showthread.php?t=1504

this is how the vent them in hawaii:
http://www.mawebcenters.com/cycleimportsofhawaii/_images/Mopeds%20And%20Scooters/08310005.JPG
only running half of the cover!

another hawaii elite, notice vent holes on clutch side:
http://www.mawebcenters.com/cycleimportsofhawaii/_images/Mopeds%20And%20Scooters/07040004.JPG

Here's how an Aprilia SR50 Ditech cools its trans:
http://www.motobikeshop.de/fahrzeuge/images/aprilia/sr50ditech/highres/03.htm

The new and exclusive Aprilia ATC (Active Transmission Cooling) system is a new and exclusive forced crankcase ventilation system with dynamic air intake and cooling fan. Thanks to this feature, the transmission components always "work" at optimum temperature. This reduces wear on components, increasing their working life, but, above all, guaranteeing high and constant performance, even in the heaviest of conditions.

Since our scooters can't have fancy system's like that, best way is either case cover cutouts or drilling holes in the right places. If you really don't believe this would help the engine and internal moving components, then sorry but thats just ignorance. imo

[burnt_toast]

here's another previous thread on it:
http://www.provoscooter.com/vbull/showthread.php?t=2794

And a picture of a highly modded racing scooter. Notice the big hole on the trans side? Hmm, wonder what thats for..

http://www.flickr.com/photos/90982314@N00/482513673/

http://farm1.static.flickr.com/227/482513673_7b6982c6b8.jpg?v=0

[OldGuy1]

here's another previous thread on it:
http://www.provoscooter.com/vbull/showthread.php?t=2794

And a picture of a highly modded racing scooter. Notice the big hole on the trans side? Hmm, wonder what thats for..

http://www.flickr.com/photos/90982314@N00/482513673/

http://farm1.static.flickr.com/227/482513673_7b6982c6b8.jpg?v=0

I do see a big hole but don't think it's in the transmission. Looks like an engine cooling air fan intake to me. Before you tell me it's on the wrong side remember, you're the one that said "highly modded."

As far as the Provo and other links did you miss the part were I said "if anyone can find an image or a suggestion by a real, certifiable racer I'm willing to be swayed."?

Sorry, but I'm still not convinced that you know better than the Yamaha engineers in regard to how much "cooling" the transmission requires for longevity vs. crap getting inside the cover.

Guess we'll just have to agree to disagree. :sunny:

[StepVino]

OldGuy, the original design is for 3-5hp, soft torque spring, ~8k rpm.
I think you are fighting a loosing battle here :). I don't like the venting
without filtering though, with you on that one.

[str8dum]

who rides their scoot in the rain/dirt anyhow? :)

well i guess the higher the tune, the more of a garage queen the scoot becomes. I have big vents in my case and its clean as can be in there. your belt would kick off more dust. you can also rivet in some mesh if you feel so inclined. I just know that my case temps have dropped 30-50 degrees since venting. that leads to lower cylinder temps as well.

[mikal]

All you have to do is compare the length that the rollers last before and after drilling holes. Previous to the drilling I would get new rollers every month, now I can usually go 2 or 3. But then again, my scoots been on the garage floor for about 2 to 3 weeks.

[str8dum]

i thnk that roller wear is more related to how much steady state driving you do. roller flat bc they sit in one spot for a long period of time.

[burnt_toast]

As far as the Provo and other links did you miss the part were I said "if anyone can find an image or a suggestion by a real, certifiable racer I'm willing to be swayed."?

Sorry, but I'm still not convinced that you know better than the Yamaha engineers in regard to how much "cooling" the transmission requires for longevity vs. crap getting inside the cover.

Guess we'll just have to agree to disagree. :sunny:

Sorry, but I'm not agreeing to anything. As it happens, NO I don't know a "real certifiable racer" to back me up.. :rolleyes: That type of proof in itself is ignorant. Closest thing here that I know of may be Crazy Scooter, since he plans on racing his Aerox. Let's see his input. Rydah and Str8dum also know their stuff.

But based on my own experiances, and all the mentioned experiances of others there are definite benefits to transmission venting. Step Vino is right, the stock cover, especially on a 50cc is made only for low hp and therefore doesn't get very hot. But if you bump that power up, a way to cool it down is almost a necessity, unless you want to constantly wear out your belt.

And what exactly have you talked to the engineers about? If your stock lil scoot needs more cooling? Obviously it doesn't, so no ones pushing you to do any sort of cutting on your cover, it would just be pointless if its stock. How much does your engineer know about modded scoots anyway?

So if you still think that transmission cooling is pointless then imo you are just being ignorant and probably senile.

[StepVino]

I'll let Timmy know that he's been called a queen. Might
be incentive to get his act together.

edit..

Wow.. didn't quite get that in before chit started flying...

[VINOGT]

I will also atest to the massive difference I experienced from trans venting on my 03 Vinos. Before venting, my trans cover would be so hot it would burn my hand in less than a second. After venting, the same ride produced a trans cover temp that would not burn my hand if I held it there for a whole minute. I am no racer, but am very experienced in modding Vinos. There were no problems with road debri, the inside of my trans case actually stayed cleaner. All the belt dust blew out the exhaust holes in the back of the case. My rollers also lasted longer. My kevlar belt had 6k miles on it.

If you want to vent, vent. If you don't, don't.

[Crazy Scooter]

Well I can only speak regarding the motors I own. My zuma is a 70cc and the transmission is not vented and its been fine so far but its not a racer. My aerox 100 (now 125rr) has a vented transmission cover but its not done by drilling holes in it. It has a built in cooling system, an air intake at the front with an air filter pod and at the back it has an exhaust. The aerox 50 vented cover from tnt and other people in germany won't fit, all the holes are different to the zuma and it appears that the vino cover is much deeper than all the covers i've seen. However for the zuma guys you're in luck...... the aerox 100 vented cover fits the zuma perfectly.... I have tried it. Not every areox 100 will fit as there are several variations but you just need to find the cover that fits gasket #5DAE54510000, a call to a uk yammy dealer would be recommended if you do go that route, I can recommend Flitwick Motorcycles @ 011 44 1525750390. Another option is to cut a hole in the front and weld a tube on for a filter and cut a hole in the back for an exhaust. See attached pic for idea's and remember the vario fan moves the air very nicely. The only dirt I see in my case is rubber off the belt. Well thats all i have to say, good luck with it :)

[OldGuy1]

Sorry, but I'm not agreeing to anything. As it happens, NO I don't know a "real certifiable racer" to back me up.. :rolleyes: That type of proof in itself is ignorant. Closest thing here that I know of may be Crazy Scooter, since he plans on racing his Aerox. Let's see his input. Rydah and Str8dum also know their stuff.

But based on my own experiances, and all the mentioned experiances of others there are definite benefits to transmission venting. Step Vino is right, the stock cover, especially on a 50cc is made only for low hp and therefore doesn't get very hot. But if you bump that power up, a way to cool it down is almost a necessity, unless you want to constantly wear out your belt.

And what exactly have you talked to the engineers about? If your stock lil scoot needs more cooling? Obviously it doesn't, so no ones pushing you to do any sort of cutting on your cover, it would just be pointless if its stock. How much does your engineer know about modded scoots anyway?

So if you still think that transmission cooling is pointless then imo you are just being ignorant and probably senile.

To quote Rhett Butler, "I apologize for all of my shortcomings."

[burnt_toast]

To quote Rhett Butler, "I apologize for all of my shortcomings."

apology accepted. :p

sorry, but this topic just got me riled up. and you were right about the pic, since it looks like the swingarm is on the other side, but it could be vented, just cant see. ;)

[burnt_toast]

Just searched those pics a lil more and found this:
http://www.flickr.com/photos/90982314@N00/492442345/

notice those big ol vent holes up front.
:cool:

[Crazy Scooter]

Just searched those pics a lil more and found this:
http://www.flickr.com/photos/90982314@N00/492442345/

notice those big ol vent holes up front.
:cool:

Those pics belong to the same club i'll be racing with :) the BSSO (British Scooter Sport Organization)

[speedfreak76]

Those pics belong to the same club i'll be racing with :) the BSSO (British Scooter Sport Organization)

If only there was a CSSO... (Canadian Scooter Sport Organization) Sigh.... :race:

[Lennox]

I do see a big hole but don't think it's in the transmission. Looks like an engine cooling air fan intake to me. Before you tell me it's on the wrong side remember, you're the one that said "highly modded."

As far as the Provo and other links did you miss the part were I said "if anyone can find an image or a suggestion by a real, certifiable racer I'm willing to be swayed."?

Sorry, but I'm still not convinced that you know better than the Yamaha engineers in regard to how much "cooling" the transmission requires for longevity vs. crap getting inside the cover.

Guess we'll just have to agree to disagree. :sunny:


Yamaha is behind the times..... there are ALOT of "cheap" manufacturers that vent there tranny from the factory.... they skimp on other stuff, but spend the time and money on this soooooo is MUST be important?!?

[OldGuy1]

Yamaha is behind the times..... there are ALOT of "cheap" manufacturers that vent there tranny from the factory.... they skimp on other stuff, but spend the time and money on this soooooo is MUST be important?!?

or possibly just poorly engineered? Yamaha's been at this a loooong time.

[StepVino]

OldGuy, there's something I don't get (with all due respect!)

You've had a carrier hopping up engines... Isn't it common, even
on cars, to improve the transmission cooling, or add it if it's not
there from stock?

[MotoringSpeed]

or possibly just poorly engineered? Yamaha's been at this a loooong time.

The issue here is that we are comparing a stock vehicle to a modded vehicle. You are essentially advocating that Yamaha, with their years of experience, has designed their machine to be optimal for all conditions; even those outside their original design parameters. Cutting holes in a trans case on a stock scooter would be silly. However, cutting vent holes properly in a scooter that now goes twice (or more) the original speed seems prudent to me.

Who are these lesser scooter companies that cut into their tranny cases?

[OldGuy1]

OldGuy, there's something I don't get (with all due respect!)

You've had a carrier hopping up engines... Isn't it common, even
on cars, to improve the transmission cooling, or add it if it's not
there from stock?

No offense taken.

Yes, but I never heard or saw anyone do it by cutting holes in the case and letting dirt in. Would you like to know how it's done?

[MotoringSpeed]

No offense taken.

Yes, but I never heard or saw anyone do it by cutting holes in the case and letting dirt in. Would you like to know how it's done?

Let's not compare apples to oranges.

I think done properly cutting holes should work fine for our purposes. Put filter material over the holes and you should be fine. :)

[burnt_toast]

Let's not compare apples to oranges.

I think done properly cutting holes should work fine for our purposes. Put filter material over the holes and you should be fine. :)

You'd be suprised at how little dirt actually gets in there with these holes.

Unless you're riding on hill country gravel roads, normal road isn't going to kick up anything substantial to cause any sort of damage. most dirt and dust gets blow out anyway if you have the vent holes in rear too.

[Lennox]

You'd be suprised at how little dirt actually gets in there with these holes.

Unless you're riding on hill country gravel roads, normal road isn't going to kick up anything substantial to cause any sort of damage. most dirt and dust gets blow out anyway if you have the vent holes in rear too.

http://www.provoscooter.com/vbull/showthread.php?t=2968&highlight=adly+vent

I have riden a BUNCH of miles with no cover at all. When tuning a new set up, or just being lazy. Venting a tranny can only help..... I wonder if oldguys kevlar belt shreaded due to heat?

[Crazy Scooter]

If only there was a CSSO... (Canadian Scooter Sport Organization) Sigh.... :race: All it takes is someone with a little know how to start a club and then all you've got to do is find enough ppl to fill the minimum stots at the track if you have one. At least thats the way I see it although I maybe completely wrong.

[speedfreak76]

All it takes is someone with a little know how to start a club and then all you've got to do is find enough ppl to fill the minimum stots at the track if you have one. At least thats the way I see it although I maybe completely wrong.

That's my problem... I live in a very redneck town, where cagers in big trucks rule, and scooters seem to never be taken that seriously. I've tried (and failed) a few times now to get some scooterists together to form a club, and maybe a racing group from there, however I am now planning for the last final push to get my club off the ground...

I have raced with the AMRA mini-roadracing club before, however the nearest track is 3 hours away in Calgary.... ,.,.

[StepVino]

No offense taken.

Yes, but I never heard or saw anyone do it by cutting holes in the case and letting dirt in. Would you like to know how it's done?

LOL to the first part. Second part I really don't care enough
to have you spend the time explaining it. Hate working on
cars.

[keefer2k4]

as far as I know anything mechanical...computers cars scooters tv's, cooling is the key to making them last a few 3/8" holes in the front and the rear is going to allow air to flow through and and dirt is not going to get in..Yamaha doesn't put holes in because the way they build them it is not needed, Yamaha doesn't expect anyone to build them into performance machines, hence why they don't sell any performance parts. If they were meant to be race machines wouldn't Yamaha get a hand in on it and sell their own parts. Its a scooter its meant to putz around town. If we decide to modify it to our own liking we have to build it suit or needs.