Updates..

Chat for Falco Owners.

Moderators: Aladinsaneuk, MartDude, D-Rider, Moderators

Message
Author
morepower
Carbon-Based Life Form
Posts: 110
Joined: Thu Mar 05, 2015 11:41 pm

#91 Post by morepower » Tue Apr 26, 2016 2:27 pm

Andy let me nip over tomorrow and try a fuel cap.. It will fit on an RS250 tank so I can seal it off and pull a vacuum over the cap to see how it breathes.... It should be OK its usually just if the breather clogs up on the Aprilia caps...

User avatar
D-Rider
Admin
Admin
Posts: 15560
Joined: Wed Jan 03, 2007 1:09 pm
Location: Coventry

#92 Post by D-Rider » Tue Apr 26, 2016 3:28 pm

morepower wrote:Andy let me nip over tomorrow and try a fuel cap.. It will fit on an RS250 tank so I can seal it off and pull a vacuum over the cap to see how it breathes.... It should be OK its usually just if the breather clogs up on the Aprilia caps...
Yep - Rich and I are meeting up tomorrow evening to do a bit of experimenting .... hopefully we'll get to the bottom of this and my fears will be unfounded :smt001
“Scientists investigate that which already is. Engineers create that which has never been.”
-- Albert Einstein

morepower
Carbon-Based Life Form
Posts: 110
Joined: Thu Mar 05, 2015 11:41 pm

#93 Post by morepower » Tue Apr 26, 2016 4:32 pm

I did a really quick and dirty test with an OEM Aprilia fuel cap and a Carbon Aprilia RS250 tank I made that I fit a breather to. I blocked the breather off and blew into where the fuel tap mounts and it had no build up of pressure and seems fine so just need to test a Falco fuel cap the same way. The RS250 tank has no breather or drain pipes either even though the OEM one does.

morepower
Carbon-Based Life Form
Posts: 110
Joined: Thu Mar 05, 2015 11:41 pm

#94 Post by morepower » Fri Apr 29, 2016 11:57 am

Went over to see Andy and yes the tank does breathe.... Just and my not be enough with the plastic insert (float chamber) the cap closes against. So I have tried my RS250 steel insert which does not have the same hole in the insert which the cap breather seals against. It works fine and I am taking the tank over to Andy to try soon. I have ordered a couple of them just in case but here is the Aprilia part number for the correct one.

AP8102526

Fowlers list them as an order only part but the price is about £16.00 plus VAT and you do not need to swap your cap for an aftermarket one and can keep the OEM locking cap on the bike.

Image

User avatar
Firestarter
Twisted Firestarter
Posts: 1410
Joined: Thu Jan 04, 2007 8:28 am
Location: Northwich, Cheshire

#95 Post by Firestarter » Fri Apr 29, 2016 1:30 pm

Just for my simple brain, things will work as they are but you're not entirely happy, the part you've listed will work ok with the standard key-locked cap?
Aprilia SL1000 Falco '04 in Black & Red

User avatar
D-Rider
Admin
Admin
Posts: 15560
Joined: Wed Jan 03, 2007 1:09 pm
Location: Coventry

#96 Post by D-Rider » Fri Apr 29, 2016 2:09 pm

I'm not convinced they will work OK with the standard cap. With it in place, sucking air out through the fuel return line can create quite a vacuum. The vacuum isn't perfect as after a few minutes, if you open the cap, the inrush of air isn't that great but if you do the same after a minute or two, it's pretty significant.
Whether or not it's OK will depend on how quickly the fuel volume decreases when "going for it".

Certainly the Falco (and Mille) are designed to breathe through one of the tubes that goes through the tank.
The RS250 appears different in this respect though I think the caps are basically the same except for the part that Rich has identified.
He took my tank last night so he could try the Falco carbon tank with a Falco fuel cap but using the RS250 part he identified (oddly listed as a "float chamber"!).
Rich reported back that works so it seems we can either go for that RS250 part in tandem with our OE fuel caps or we can find aftermarket caps with a different venting system.
“Scientists investigate that which already is. Engineers create that which has never been.”
-- Albert Einstein

User avatar
Viking
SuperBike Racer
SuperBike Racer
Posts: 1150
Joined: Wed Jan 03, 2007 10:17 pm
Location: The land down under

#97 Post by Viking » Sat Apr 30, 2016 7:09 am

Hey all,

The CF tank is on the bike - took a shitload of fiddling. :smt013 Compared to the old plastic tank, the CF one is over 1/4" longer, so all the mounting brackets are screwed up.

I ended up filing the bolt holes in the front mounting bracket into ovals, all the way back to the 'vertical' bit of the bracket, and then file about 3mm out of the rear bracket (where the long bolt runs through the tank pivot point).

I also had to relocate all the wiring for the tip-over sensor and the fuse-block thing to get enough free space.

I fired her up, and everything works (yay!!) but haven't run her long enough to see if there's an issue with the tank not breathing correctly.

Given my current lack of free time, it may be a while before I can give her a proper test.

And I have to say - with the dark coloured frame rails, the tank looks f**king amazing!!

https://drive.google.com/file/d/0B2EFSY ... sp=sharing

https://drive.google.com/file/d/0B2EFSY ... sp=sharing


EDIT: I've given DropBox the finger and moved to Google Drive, so updating some of the links to pictures.
Last edited by Viking on Mon Oct 31, 2016 1:15 pm, edited 1 time in total.
It's the V-twin thing. There's just something about it that inline-4s don't have at all, and V-4s don't have enough of.

User avatar
Viking
SuperBike Racer
SuperBike Racer
Posts: 1150
Joined: Wed Jan 03, 2007 10:17 pm
Location: The land down under

#98 Post by Viking » Sat Apr 30, 2016 9:59 am

I don't think we need to worry about the filler cap and breathing issues.

If you think about it - the two hoses come into the recess under the filler lid, but outside the rubber seal that keeps the fuel inside the tank.

If you look at the bottom of the red plastic piece on the filler cap there are 4 small holes. These appear to vent to slots above the rubber seal - they do allow the passage of air, as my housemate blew through them. (The crazy bastard.)

Perhaps it's best with a crude drawing...

https://drive.google.com/file/d/0B2EFSY ... sp=sharing
Last edited by Viking on Mon Oct 31, 2016 1:15 pm, edited 1 time in total.
It's the V-twin thing. There's just something about it that inline-4s don't have at all, and V-4s don't have enough of.

User avatar
D-Rider
Admin
Admin
Posts: 15560
Joined: Wed Jan 03, 2007 1:09 pm
Location: Coventry

#99 Post by D-Rider » Sat Apr 30, 2016 12:21 pm

Not quite that simple - though that is effectively what adding the RS250 part allows to happen ... I'll try to get some pics later to explain.
“Scientists investigate that which already is. Engineers create that which has never been.”
-- Albert Einstein

morepower
Carbon-Based Life Form
Posts: 110
Joined: Thu Mar 05, 2015 11:41 pm

#100 Post by morepower » Tue May 03, 2016 7:53 pm

Viking wrote:Hey all,

The CF tank is on the bike - took a shitload of fiddling. :smt013 Compared to the old plastic tank, the CF one is over 1/4" longer, so all the mounting brackets are screwed up.

I ended up filing the bolt holes in the front mounting bracket into ovals, all the way back to the 'vertical' bit of the bracket, and then file about 3mm out of the rear bracket (where the long bolt runs through the tank pivot point).

I also had to relocate all the wiring for the tip-over sensor and the fuse-block thing to get enough free space.

I fired her up, and everything works (yay!!) but haven't run her long enough to see if there's an issue with the tank not breathing correctly.

Given my current lack of free time, it may be a while before I can give her a proper test.

And I have to say - with the dark coloured frame rails, the tank looks f**king amazing!!

Image


Image

Odd.. Andy thought there was a difference in the fit the first time we offered up the tank... But we then took the new plastic one and it fitted exactly the same as the carbon one...

Andy will have his tank back tomorrow with the metal insert (float chamber) fitted I use on the RS250. I have two more arriving this week but I will talk to Andy about a possible free mod to the plastic one if he is willing to try it...

User avatar
D-Rider
Admin
Admin
Posts: 15560
Joined: Wed Jan 03, 2007 1:09 pm
Location: Coventry

#101 Post by D-Rider » Tue May 03, 2016 10:57 pm

Yep .... looks as though that's another oddness about the yellow bikes - even their tanks don't seem to conform.
:smt009


The mould was taken from a brand new yellow tank that Nooj sourced from the USA


Oh - and sorry I've not yet found time to explain about the breather in more detail ... I will get round to it sometime.
“Scientists investigate that which already is. Engineers create that which has never been.”
-- Albert Einstein

morepower
Carbon-Based Life Form
Posts: 110
Joined: Thu Mar 05, 2015 11:41 pm

#102 Post by morepower » Wed May 04, 2016 10:50 am

Had a play with the plastic insert (saucer) that the cap fit into. Sorry Andy if you want I will buy a new one..

I ground back the cupped vent in the plastic to be flatter and more like the RS250 tank one..

Image

Image
The steel one does not have a hole at all so just shortening the plastic one would be the same.

It does breathe more and blowing or sucking into the fuel pipe has a little resistance but then the breather hole in the cap is only about 2mm in size so would be the one bit of resistance and now the flow has increased so should now be fine..

User avatar
Falcopops
GP Racer
GP Racer
Posts: 2514
Joined: Mon Dec 18, 2006 4:00 pm
Location: NOT sweating in the tropics

#103 Post by Falcopops » Wed May 04, 2016 10:53 am

on the back of all the talk about venting and a wet ride resulting in water not draining, I was having a look and I thought the same as Viking. The breather tube opens under the steel part of the fuel cap outside the rubber seal, so I was thinking that the tank should breathe ok.

I'm more concerned about the age old issue of rainwater passing the outer cap and having no drain and then falling into the tank once opened.

User avatar
D-Rider
Admin
Admin
Posts: 15560
Joined: Wed Jan 03, 2007 1:09 pm
Location: Coventry

#104 Post by D-Rider » Wed May 04, 2016 11:33 am

Yes as standard it doesn't vent ito the area under the flap as it seals to the bit that Rich has modified and the air path normally then goes through one of the 2 pipes in the tank - which don't exist on the carbon tank.
What Rich has done is what I was thinking of doing myself (so no problem Rich - I don't need a replacement). This should stop the seal forming and allow it to breathe.

It is the other hole that on a standard bike acts as as a drainpipe through the tank and keeps out any rainwater. Clearly we no longer have this facility so it remains to be seen how big a problem really exists. I must admit, now understanding a bit more about how the tank breathes and seals ..... and how it always rains whenever more than 1 Falco is within 2 miles of another .... I'm a bit apprehensive.
Of course, there is that lip around the filler hole and you only tend to open the filler when on the sidestand - so I guess a fair bit has to collect before it stands too much of a chance of entering the tank.
Maybe we just need to have a handy sponge available when we open the tank .... or cut a small notch in the flap into which you can insert a tube on the end of a syringe to suck out any excess rainwater before you open it.

Any better suggestions gratefully received.
“Scientists investigate that which already is. Engineers create that which has never been.”
-- Albert Einstein

morepower
Carbon-Based Life Form
Posts: 110
Joined: Thu Mar 05, 2015 11:41 pm

#105 Post by morepower » Wed May 04, 2016 12:39 pm

Dont forget you have the rubber seal round the cap too so the amount of water getting down there will be reduced and so far in over 18 months now I have not had one person have an issue with water in the fuel tank and all aftermarket tanks are built the same way with no drain.


If you do get water in that area you can get to it just by opening the cap and as andy pointed out use a syringe.


Glad me grinding back the raised plastic was OK.. I had to know..

Post Reply