How do I solve this fan issue?

[marylandmark]

Jered posted a message about a pic in my Scoot Garage and looking for input..


Mark... I'd be worried about the exhuast and the shroud... as your sucking HOT air and blowing it on the fan...

What do I do about it? That fan blows air on the ____ ? Tranny? Motor?

I guess what I am asking is would it be better to diable the fan? It is like a hair dryer right now blowing hot air on whatever it is blowing on.

When I get my scoot back I will check to see if I can take the fan cover off, seal it up some how and then put it back on. It is plastic so I could glue or even try to melt flat piece of plastic to it. Maybe put some black heat resistant tape over it as well.

[Lennox]

did they cut the shroud to fit the pipe???

[marylandmark]

Yup= cut the shroud to fit the pipe..

[Lennox]

If I was you... I would mold in a piece of plastic to keep the fan area sealed! Do you have the "cut-out"? You can reform it and glue it in with a soldering iron :naught:

[marylandmark]

Nah- they cut it and tossed it I am sure. I saw it when I picked up my scooter when it was new. They said they had to do it to fit the pipe on there and it is all good. I was thinking it was not a good thing but didn't think too much about it until Jered said some thing and now I it is stage III'ed.

I'm going to buy some black plastic, a trash can or some thing like that and melt it on there. I hope it is not too hard to take apart....

[XPS1210]

The fan blows air over the cylinder... hence air cooled...

your taking a pipe that is a good couple hundred degrees or more.... (where it's contacting) and pulling hot air from him... as it blows air onto the cylinder....

might be nice for cool air riding... but don't ride on a hot day... Just my opinion...

[marylandmark]

Yea- I think I am going to try to seal it up as soon as I get it back. From the looks of the picture it might just be 3-4 phillips screws right there- Don't have to take a ton of plastics off and so on.

[XPS1210]

3 size... But it's weird and easy to strip...

[Booya]

Kinda on this same subject... Has anyone taken off the plastic shroud that covers the cylinder head? Wouldn't that help more than anything to keep it cooler?

[Lennox]

if you cut holes, and had good air flow then at top speeds it would be fine...........but when stopped at a red light, the plastic shroud, and forced air (from fan) are needed to keep it cool.

[marylandmark]

I would guess anything that increase air flow over it would help keep it cooler. Would that leave your cylinder unprotected?

[hybridrazz]

i wouldnt on my stock engine my fan broke and took off the covers ,and rear engine cover all the cool air blowing over the engine didnt keep it as cool as the fan did it melted a piece of plastic close to the cylinder.Im thinking you could get some aluminum sheet metal ,and bend it around that lower piece, you could attach it with small bolts or screws.I also remember seeing how the handmade pipes don't always fit the same maybe the hanger could be bent some to make the pipe fit better.

[Booya]

Doesn't it seem like placing a cooling fan over the exaust is a bad idea?

[XPS1210]

if I understood what you said....

DO NOT TAKE THE SHROUD OFF OF THE CYLINDER...

that is set up to blow the air over the cylinder... the fan moves enough air over the cylinder... if you take the shroud off... then you eliminate the air flow and cause it to over heat... PERIOD... do not remove it.

[Booya]

Straight to the point and well said. I'll nix that idea right now.

[Aviatrixie]

I just looked at the picture of your fan shroud and have to say... what in the world were they thinking when they did that?!! Either you are sucking hot air over the pipe or blowing cool air over the pipe. Either way you are losing cooling air flow to your engine. That's not good!

[Lennox]

even after you seel it back up, it might not be a bad idea to use the insulating tape on the pipe in that area......

[van ringostein]

Whew, after looking at your pipe, I had to pull a pic to look at mine, mine is not as big, so it is further away from that shrowd, so I am kinda thinking that I will be ok.

[florida derbi rocket]

Honestly Mark, They look like a reputable shop...I would ask if they can move or bend that exhaust away from the pipe. and since it (the fan cover) is a stock part..They should scare one up for you...Or order a new one. THERE... I said what everyone else was thinking..This incident was an education in What the term "Air-Cooled" Really means... Just tell them it was your idea..you have spent a lot of Pesos there, Hombre. :p John

[XPS1210]

Whew, after looking at your pipe, I had to pull a pic to look at mine, mine is not as big, so it is further away from that shrowd, so I am kinda thinking that I will be ok.
your pipe is fine... that's how they are supposed to be...

not like MM's which is cut into the fan shroud...

[marylandmark]

My pipe is routed up against the fan shroud..

John- I have the Piggy motor so I guess it is mounted different than yours- that way you have more room.

Here it is taken off the bike- going to see what I can do to get it back in working order...

[Iceman]

Does that inner grid turn or is it stationary. If it is stationary, I would form a sheet of aluminum to cover it and seal it real good. If what I am interpreting from the pic is correct, the cooling air enters the center of the cover. The aluminum would offer some degree of protedtion but I think I would get some heat shield wrap around that section of exhaust (like they use on car headers). Has this problem ever cropped up before (particularly the Zumas) when changing exhaust?

[hybridrazz]

Thats what i was saying before use a sheet of aluminum ,and bend it to that shape,and attach it with very small screws or bolts would work perfect.

[marylandmark]

If it were not cut; air enters the middle hole which is protected by a few bars of plastic, then the stationary grid protects anything big enough to squeeze through the middle hole.

I ended up taking out the inner grid, cutting up a plastic dog bowl and fitting it between the outer shroud and the inner grid. Not air tight but for now I figured anything that would restrict air flow or suction off of the pipe would work.

While I was playing around I had a better idea that would almost negate the fan sucking air off the pipe.. How about a "ram air" type device? Get a 2 inch long 45 degree pipe the diameter of the middle hole. I can poke out the center hole grid and glue it in there. The inner grid will still offer as much protection as I have now. The faster I go, the more air would be forced over the fan. The excess air would cool the fan and then escape through the hole cut in the shroud- blowing any air from the exhaust away and cooling the exhaust because the air would be blowing on that. I know- colol the pipe maybe .0002 of a degree -but than sucking in hot air is the main thing.

What do you think? Seems that would be a lot more air flow which would provide better cooling as well as solve my "exhaust sucking into the fan issue".

[Aviatrixie]

Hi Mark :)

You have the right idea, preventing hot air from being pulled over your pipe. But that pipe gets really hot and I'm assuming the plastic dog bowl piece is really close to your pipe. Keep an eye on it as I suspect it may melt. Probably sheet metal or real thick foil would work better. Just a thought.

[marylandmark]

Thanks and good point!

I figured the dog bowl was thicker than the plastic shroud that is already there and further away from the pipe than the shroud so should be ok.

Once I thought about a "ram air" type thing I put the dog bowl as a temp solution.

My pipe is still not "melted in"- it has a clear coat on it that bakes on to the pipe and turns a diluted coffee color. Once that is done I plan on wrapping it with exhaust wrap if my ram air thing doesn't work.

[hybridrazz]

That make universal air scoops to screw to the plastic shrouds,any color ,and carbon fiber copy style.

[marylandmark]

Sent you an email hybridrazz

[hybridrazz]

Ok thanks mark i sent you a email back.

[florida derbi rocket]

sorry so small..it was one of my avatars...I could have this wrong..but I think the forum laughed at me for suggesting ram air in the past.

[hybridrazz]

Ive always thought it was a good idea cooling the engine more.

[Iceman]

This whole discussion made me curios about my Zuma so I took a look and it appears to have a forward facing scoop and a bottom opening that allows excess air to pass through. It looks like it is pretty well open and far from the stock exhaust. May see some room to tinker since this thread started me thinking about better cooling :confused:

[Lennox]

There IS room for improvement with the stock "ram-air"

Check this out (http://www.provoscooter.com/vbull/showthread.php?t=2317)

[van ringostein]

sorry so small..it was one of my avatars...I could have this wrong..but I think the forum laughed at me for suggesting ram air in the past.

Where did you get that ram-air piece....I personally have never liked a sideways facing shrowd, would prefer to have something like that on my derbi

[Lennox]

this is from my friends MZ Moskito...... when we installed the pipe, there was at least an 1/8" space between the pipe and shroud. The heat melted it, and now it touches and stinks. Mark, I think metal might be needed.

oh BTW, the rust on the pipe is what happens when you live near the beach, and leave your scoot outside all the time :rolleyes:

[Aviatrixie]

HAH!!!! I knew it!!!!!! LOL

Mark... ditch the dog dish and use metal, honey. ;)

[marylandmark]

HAHH- Yes dear, I knew you were right!

I threw in the dog bowl just to help me until I got a ram air going. I think I might order one of these. Not really a fan of carbon fiber going to get that because it will match my air fliter..

http://badmotorscooterparts.com/misc/scops.jpg

http://badmotorscooterparts.com/misc/tscop.jpg

[Aviatrixie]

they look like bizarre propholactics

[marylandmark]

No comment... HHAHA J/K!

I think I can fabricate (I love that word!) some thing that would work better than those "bizarre propholactics". TomorrowI will get some PVC to see what I can come up with- I was thinking some thing with like John/FL DerbiRocket has. Not sure if going with metal or PVC but PVC easier to work with so going to mock it up first and then decide what material to use and make it all pretty.

[Aviatrixie]

no!!!!


Kinda on this same subject... Has anyone taken off the plastic shroud that covers the cylinder head? Wouldn't that help more than anything to keep it cooler?

[florida derbi rocket]

Where did you get that ram-air piece....I personally have never liked a sideways facing shrowd, would prefer to have something like that on my derbi Hey Ben. that scoot picture isnt mine..although I am still going to work on something like that. My fan shroud (as well as rear fender) is a LOT smaller (lower profile) and the fins are shorter on the fan itself ,so I know it moves less air than Marks does. Mine...2002....Marks...2004. But there is a raised circle edge that I could fit a scoop around. hmm..another project ...another day
::handleba John

[marylandmark]

I noticed some thing- don't think I need to worry but figured I would toss it out there you fine folk to comment on.

The inner ring is the only protection for the fan- if I cut that grate out like I plan on doing and then glue in a PVC 90 if anything we to get into the PVC it would route straight into my fan blades.... I guess I could re-use or fabricate (did I tell you how much I love that word?) the grate that I cut out..

[hybridrazz]

Yeah its just there to keep debris out of the shroud,and away from the fan.Im thinking maybe you could re attach it the the pvc elbow or just leave it on the shroud seems like it would'nt make much of a difference where it was located on the shroud, or in the elbow would still be a slight restriction.

[marylandmark]

I went to the store and bought 7 PVC fittings:
45 and 90 degree 1 1/4 inch
45 and 90 degree 1 1/2 inch
45 and 90 degree 2 inch
90 degree 1 inch to 3/4 inch reducer

I had a few questions so I went with cutting out the smaller center webbing of the fan shroud (see above for pic with center webbing before). Then put in the 3/4 side of the 3/4 to 1 inch 90 reducer in this hole with the cut out webbing glued inside the PVC to protect things from flying up there. This gives me a larger end to catch air but a good beginning mounting option- if I need more cooling I can cut the rest of the webbing and mount a larger PVC or if this doesn't do any good I have some protection for my fan still...

Would a large pipe force too much air on the fan which in turn would the the motor to have to work harder to turn the fan? The fan is connected to the magneto and then both of them are connected to the crank so if I am causing resistance I am losing RPM's?

Anyway- here are the pics. Fits in there NICE- think PVC is easier to mount (pipe glue could glue me to the ceiling) than metal. I am wondering if I can make get it black to match the bike better? I also have some Marine-Tex that I use on my boat and it seems like to glue anything to anything so that might be an option as well.

4th pic gives a really has a good idea of where it is getting the air from- the black platform above the PVC is the rear passenger foot rest, hard to see but the white (really grey) stripe on the top right of the pic is the center of the bike- battery under that, the black at the bottom with the grey at the front where it looks like the pipe is coming out of is the bottom faring which would direct air into the PVC..

[florida derbi rocket]

Mark,Here is my 2002 fan shroud in case you wanted to see it. It is just under 4" wide (the opening)..so I cant go with PVC....gonna be way too big...but just for kicks I'm gonna go through the shed and look. Oh...I am picking up my Piggy Motor tomorrow , so any photo's you post are a help....Thanks, John

[marylandmark]

WOW- mine is only 2" and that is iffy, would have to take the shroud off to make sure but think what I have is going to work ok.. You don't even need an intake- pleanty of clearance for your pipe and 4" opening should do it. I don't think I would have never messed with mine if they didn't cut it for my pipe and that became an issue.

[florida derbi rocket]

I understand . I Have the unique oportunity to try to Graft a 2003/4 Piaggio Motor to a 2002 frame.. Because of your problem...I will be carefull when I buy a pipe for this motor...I will make this fit if it is not a direct fit. It cant be that far off...and I have the ultimate "Fabricator" friend involved.(Full Metal shop) ..he really is a McGuyver...it should be fun...Thats what this scooter thing is half about...50%-Riding...50% -Tuning..!!...Or..Umm...might be different for some of the other Members... For anybody else that remembers.. I am still dealing with that "Top Performance" Crank....they are supposedly sending a second one..from Jolly olde England..after 6 weeks they admitted that it was lost. So...I will have 2 motors if the Piggy motor fits.. o_o John

[marylandmark]

Thought that 2nd crank was going to be overnighted?

My setup runs great so if you have the same issues with the pipe/fan shroud just do what I did.. Once I clean it up I think it will look pretty slick- with that PVC next to the pipe makes it look like I really have a hopped up machine! Then I start it blast a 0-60MPH in 30 feet with my pipe rattling your bones. Now your girl wants to ride on the back... :cool:

[marylandmark]

Would a large pipe force too much air on the fan which in turn would the the motor to have to work harder to turn the fan? The fan is connected to the magneto and then both of them are connected to the crank so if I am causing resistance I am losing RPM's?


Anyone think this is an issue? The air is directed towards the center of the fan so not really blowing on the blades might make this issue a non- issue?

[XPS1210]

it's fine mark... you worry to much! LOL!

You are taking a scoop and forcing air onto the fan, center or not it's getting air... more at speeds then standing still but your still getting air...

[marylandmark]

Ok.. ::unk::

I thinking like like if I took my air compressor and blew air at the blades of my garage fan it slows them down or could even stop them.. I thought it would be a "non-issue" but wanted to check with you guys/gals 1st before I glued it on there.

[marylandmark]

GRRRRRRRRRRRRRRRR

When I 1st got my scoot back with the stage III, I rode it about 5 miles and it overheated. They said this was caused by the parts breaking in, which generated more heat and the bike shut itself down, vapor lock or some thing like that. I was ok with that answer and it made sense- have been riding it ever since with 0 problems. I have 104 miles on it- I took it in the shop to stage III it with 12 miles on it. Break in should be done as far as heat build up issues..

Frickin 70+ degrees outside and sunny today- ready to rock on my scoot!! I ran my scoot 5-6 miles 2/3 throttle to WOT the whole time. Then started cutting out and then shut down. 45 minutes later still would not start so called a buddy, tossed it in the truck and brought it home. 2 hours later she starts fine..

So what to do? LC motor would be nice but dealer said I didn't need that unless I was trying to run 50 miles at a time WOT..

GGGGGGGGGGGRRRRRRRRRRRR

Any ideas anyone?

[hybridrazz]

The fan should keep it cool enough, did you get the shroud fixed?

[marylandmark]

I have the plastic dog bowl piece covering where the shroud is cut at. The plastic shroud, dog bowl- none of it is even curling if too much heat was coming from there. It could still be an issue, however with the dog bowl blockage and the "Ram air" thing it would almost take an act of God for the exhaust to be sucked in by the fan..