Air Filter for Avanti

[Rick]

Hi Chaps

Im looking to put an Air filter on my Avanti do you think this will be ok, will it get enough air? it will be on a 30mm Dellorto
http://www.pmtuning.co.uk/pm-tuning-x-t ... -phbl-phvb
I don't want to be putting a hole in my panel and get it wrong and I rather like the red

Chars Warrick

[Adam_Winstone]

I think it will strangle it quite badly. That is listed for PHBL carbs, which go to a maximum size of 26mm and are very common as 24-25mm versions, which might be ok with such a small/restrictive filter but I'd not use one on a bigger carb. Also, I imagine PM recommend these for PHBL on reed motors (as in the 25 PHBL that was fitted to my pal's PM tuned Runner 180), which don't need to 'gulp' as much air as quickly as a piston port motor (shorter inlet timing).

Also, the bit about double foam layer = better filtration but more restriction. What you need is a much bigger/longer filter, ideally single skinned. I've used the Breathe Sweet filter from Cambridge Lambretta in combination with a GP airhose + short plumbing adaptor sections so that it fits correctly, comes back away from panel and sits nicely between toolbox and petrol tank. I think that Coaster may be doing the same and may have posted some photos on here(?).

NB: Small filters will completely strangle a tuned piston port motor... bigger filters can work very well.

Adam

[Minority]

You mean like this Adam?

[corrado]

Above picture shows a breath sweet type filter on top of a GP air hose. The complete breath sweet has a bigger rubber air hose.




The breath sweet filter is better than an adapted gp air hose as the rubber part has a bigger 60mm mouth to fit directly to the screw on plastic bellmouth that you should already have on your Dellorto PHBH carb. The plastic screw on bellmouth would have come with the carb when new if it's not very old, they can be purchased separately if your carb has a threaded section to screw it onto. A 60mm hole going into the carb is going to allow more air into the carb than the restricted GP air hose.

[coaster]

....I think that Coaster may be doing the same and may have posted some photos on here(?).

Yes I did Adam although I can't remember if I ever posted any pics I'll have a look on my other laptop when I get home. Either way, I found that by using an MB 'short' rubber I am able to use the breathsweet elbow AND filter without any significant squashing of the elbow. That's on an Avanti with 30 PHBH slimstyle panels (Jet 200)

[Adam_Winstone]

^... yep, that's the kiddie. I found that the standard Breathe Sweet hose, although a better option if it does fit with your manifold/rubber/panel combination, was too big and squashed badly against my GP panels, even with a machined shorter CDC manifold.

There are various configurations that can be used with the Breathe Sweet filter, you just need to figure out what works best for your setup.

Adam

PS - Well done and thanks to all those that came back with photos

[speedy]

Eh up folks, just a question regards the breathe sweet. I would lie to use one on my Jet 200, but wonder if it will work properly regards airflow? I have bought a new 30mm phbh solid mount job and it appears the screw on plastic bellmouth is now an accessory, so gotta get one of those. Now with the jet frame having no airhole on the top of the loop, would there be sufficient air under the panels for the filter system to work? cheers,Speedy.

[corrado]

I don't think the old solid mounts PHBH carbs have the thread at the carb mouth to utilise the threaded plastic bellmouth and you'll probably need to use the GP air hose. The breathsweet hose was available to fit a 44mm fitting as well as the 60mm one, mainlt to fit Mikuni TM24 but it might fit the solid mount Delly too. You'd need to measure the opening on the carb.
Breathsweet is also available in 50/52mm [forget which exactly] that fits PWK/Keihin copies and some Mikunis.
I've also bonded breathsweet filters onto 20mm GP hoses to fit PHBL carbs.

[coaster]

..... with the jet frame having no airhole on the top of the loop, would there be sufficient air under the panels for the filter system to work? cheers,Speedy.

As mentioned above, I'm using one on my Jet 200 with an Avanti TT3, no problem with air flow, there's a sodding great big gap between the frame and the road

[Rick]

Thanks for the replies.. Tbh I've never had much luck with filters in the past I did look at the breath sweet filters but sort of made my mind up on putting a hole in the panel. My scooter drinks so a bigger tank is on the list. Are there any other filters that would work with an Avanti?