DIY air filter

[budd]

Last week I gave the old girl a pre summer service, usual stuff oil, air-oil filters, plugs etc anyway when I changed the air filter I noticed the little foam inserts that protect the carbs from dirt ingress were falling to bits, so following some forum advice to use some air filter foam to make replacement inserts I ordered a piece of air filter foam from ebay (£4).

Well the piece that arrived is aprox 30cm x 30cm so I've got plenlty left over after cutting the required inserts. that's when I noticed the old panel air filter laying on trhe bench and thought why not cut out the paper element part and replace it with foam, the old filter was bound for the bin the filter foam is surplus to requirements so nothing to lose.

So I cut out the paper element part of the old filter, cleaned up the panel a bit then cut the foam very slightly oversize and bonded it in, the grill/mesh supports the foam so I can't see any rerason why this wouldn't function in a similar way a aftermarket filter.
Once the PU adhesive is fully dried (tomorrow) I'll oil it and give it a try, see if it makes any difference.

[VTRDark]

O' it will make a difference alight!!! Most likely cough and splutter until the carbs are dialled into it.

(:-})

[budd]

O' it will make a difference alight!!! Most likely cough and splutter until the carbs are dialled into it.

(:-})

sounds like fun
can I get away with tweaking the carbs or do I need a jetting kit?

[VTRDark]

It depends how lean it makes it really. Maybe shims (small washers) under the needles will help and 48's pilots if you have 45's. It's trial and error really, but don't expect to put a filter in like that and expect it to run perfect without any carb work. Note if the filter is over-oiled then that will also make it cough and splutter too.

(:-})

[budd]

I light mist of PJ1 foam filter oil will surfice I think, then I'll stick it in tomorrow and see how it behaves looks like I'll be fiddleing with the carbs, at least it'll keep me out of the pub

[lloydie]

Or it may restrict the air flow ! Depends on how dense the foam is .
For the sake of £20 for a new standard filter is it really worth all the trouble ?

[budd]

Or it may restrict the air flow ! Depends on how dense the foam is .
For the sake of £20 for a new standard filter is it really worth all the trouble ?

a new OE filter is currently fitted as par service, it's the old one I'm chopping up, if it causes problems i'll just bin it and revert to stock.
Foam is generic MX bike stuff 15mm thick so should be less restrictive than a old OE filter if lightly oiled, I suppose part of the fun of experimenting is the possibility of it going wrong and not working as planned, as witnessed on this very forum more than once.

I was just interested in having a bash with a performance air filter and tweaking the carbs but didn't want to fork out for a Pipercross, BMC or K&N and a dyno-jet kit.

BTW I'll probably be needing some 48 pilot jets and some needle washers where's the best place to get these?

[VTRDark]

There's a very good chance you already have 48's fitted, you wont know until you open the float bowl. If you have never opened the carbs then you never know there may even be a jet kit already installed.

Otherwise there's plenty on eBay. This place is out of stock of 48's at the moment but this gives you an idea as to which type these carbs use.
http://www.ebay.co.uk/itm/130709903414? ... 1423.l2649

Do make a note of all the settings as things stand so it's easy to go back to them if needed and keep notes of any changes you make

It's a whole new trip if you have never played with jetting before and is very rarely a pull carbs, open up, make changes and work perfect straight away. Expect to be pulling the carbs out a few times at least. Great learning curve if it's something you have never done before though.

Have a good read through the following.
http://www.vtr1000.org/phpBB3/viewtopic ... 31&t=14214

(:-})

[tony.mon]

Expect to be pulling the carbs out a few times at least. Great learning curve if it's something you have never done before though.

(:-})

Yep. Once you smell of petrol it's all you will pull.

[budd]

thanks for the input
I've not touched bike carbs since the early '90s when I stopped riding bikes due to waking up in hospital to many times before ending up severely and permanently injured, I then switched to cars but by that time it was all EFi and ECUs so it’s been a while. But it will be nice to tinker with some ‘oily’ bits rather than just plugging in a laptop and flashing the EPROM

[darkember]

What is the standard size on the jets as I'm about to open the float bowls once I manage to remove the shredded possi heads. Damn Honda and their cheap fixings.

[lloydie]

What is the standard size on the jets as I'm about to open the float bowls once I manage to remove the shredded possi heads. Damn Honda and their cheap fixings.

175f 178r

[VTRDark]

I manage to remove the shredded possi heads.

Link to hex head replacements.
http://www.ebay.co.uk/itm/Keihin-Carb-F ... 53e4ffdfc6

(:-})

[budd]

put the DIY filter in this morning along with the little carb filter sponges then went for a quick ride around the block, one junction up the M1 and back with a bit of riding through town and along a dual carriage way probably 10 miles or so, and amazingly it feels great no spluttering or flat spots pulls nice and smooth in fact as well if not better than at any time I’ve owned it.

I’ll put my leathers on tomorrow and take it for a longer run see if it continues to behave well and also whip the front plug out when I get back and have butchers at that, if it’s a nice browny-grey then I can assume it’s running OK and it’s happy days.

Also I’ve found a local source for all my jetting needs (if it turns out I do need some) so if I do encounter problems I can get hold of the jets and hopefully cure any issues.
I think what I need to do is take the carbs off anyway and see what is actually in there, because as someone mentioned earlier it may have been re-jetted previously, but that can wait till the weather turns nasty again, I think I should be riding rather than dismantling it if the weather is nice.

[darkember]

I manage to remove the shredded possi heads.

Link to hex head replacements.
http://www.ebay.co.uk/itm/Keihin-Carb-F ... 53e4ffdfc6

(:-})

Got some nice SS pan heads with a deep slots from work, just the biscuit