Nope, can't mod it..

I'll get some better pictures tomorrow.

It'll be fine dude, it's not a bodge, it's a refinement.. :)

Nope, can't mod it..

I'll get some better pictures tomorrow.

It'll be fine dude, it's not a bodge, it's a refinement.. :)

fair enuf matey, good luck!

why dont you get some slightly angled pipe ? surely that gap is way too big ? or maybe just use a different filter ?

Slightly angled pipe? What do you mean?

If you've got a better suggestion for filtering air properly on a set of cbr carbs that isnt filter socks (which apparently are crap, and won't filter all of the brass inlet tubes anyway) I'd love to know, although this pipercross filter I'm using at the mo wasn't cheap!

well tbh me and salty and a few others that were at gti fest arent running any filters and it doesnt seem to be a problem i do have proper sock filters but they seem to block some of the air supply and my brass tubes are covered by some thin ally plate i mate that bolts onto the seal and has a hole in the middle for the trumpet i would put a pic up but am not able to upload any more atm

Thats why I don't want to use socks

And I do 1000 miles a month so don't fancy running without filters and cleaning the carbs every other week.

I've decided to weld extensions on to the runners now, although cutting the ends square ready to accept them is a bitch, if only I had a milling machine..

its to do with the way the carbs fuel, single socks dont work well and I've heard reports of them playing havoc with fuelling and it would be better to run without filters at all, the one forrest has is the ideal as it encompasses all 4 or the type that cover just 2 will suffice.

If you bring the carbs closer use something to hold them in place and it should clear the master cylinder.

Cheers Cymro, I thought I'd read that that was the case. I know you need space around the trumpets for the air to flow properly so when I get this fitted (and my manifold finished.. again!) it will work to its best potential. Currently I'm trying to figure out how to make sure my manifold is flat ready to receive the new extensions. Also how to grind the inside of the weld when it's joined. I suppose I'll need to but a long necked die grinder. Doh, this is getting expensive!

i run the twin carb filters, there is something about connecting the vents at the top of the carb back into the air filter, the slight negative air pressure inside the air filter area helps the slides open, but I cant remember where I read it.

new link I've not seen before too: http://www.classicfordmag.co.uk/files/2011...LF166.bike_.pdf

Shit son!

I can't imagine what that'd be like on the over run at 7000rpm!

extending the tubes would be alot better than flexy hoses i guess.

why dont individual socks work well then?

Shit son!

I can't imagine what that'd be like on the over run at 7000rpm!

remember you've only got high manifold vacuum when the engine is at idle. The vacuum drops as the engine speed increases, not to mention the fact that there is much more flow with these carbs as the slides open. PS I haven't driven it like this. Am getting my steel manifold reworked first.

remember you've only got high manifold vacuum when the engine is at idle. The vacuum drops as the engine speed increases, not to mention the fact that there is much more flow with these carbs as the slides open. PS I haven't driven it like this. Am getting my steel manifold reworked first.

I know you said you're sleeving the hoses.

But.........

When the throttle plates slam shut there will be high vacuum behind them.

And at higher rpm it the vacuum will be higher.

So at the redline when you lift off, I imagine the vacuum would distort those hoses even more than at idle.

Thats fine dude, I know what you mean, I'm going to weld 2 inches more tube on the end of each runner to account for that so it will be fine :)

When you change down a gear at speed, and the rev counter shoots up on engine braking, those hoses will be twice that bad, and likely risk collapsing into the combustion chambers..

I've pointed out in various places on here, with script and pics, you can only use hardened stainless spiral wire reinforced tubing. Mine were industrial food-grade vacuum tubes meant for multi million pound machines in a plastics factory.

I now run a full steel manifold, and it's no more responsive than it was with said tubing.

Thanks mikey, I was chatting to you the other day about the hose, as my manifold is 38mm OD and my carbs are 42mm OD I'm gonna use this hose as it will stretch over the carbs but extend the runners so that they are right up to the carbs faces. Job done. Didn't want to use hose (even like yours) over this distance as it will be a weak point whatever hose I use. Slowly I'm learning if a jobs worth doing its worth doing well.

go can get hoses that are different sizes at each end bro

The coiled hose is easier to expand - twist a spring one way and it expands, twist it the other and it contracts.

My carb bodies were a good 6-10mm bigger than the port flanges i'd made, yet some hot water and a twist in the right direction saw them fit both ends. Cant do that easily with the braided stuff you're using.

What heat resistance does it need? Is 60deg enough?

update - heres some pics of my manifold with the vac feeds fitted

ready to have the extender tubes welded on

Update - got my manifold now sorted and fitted. It runs ok although I know I need to sort jets etc just like stinkypete.

Got a few questions about the vacuum advance. Should the ignition advance under higher revs and the mark on the crankshaft pulley move anticlockwise or is it the other way around? It works like that under gentle opening of the throttle but opening it too harshly sends the timing mark clockwise..?

anyone got any ideas? cheers

I am getting it set up by PDQ developments in slough on monday.

But I've found it runs fine without vac advance.. once it's warm and the choke is back in. Although a little thirsty at the moment until it's jetted (100 miles for half a tank!)

When I get my internet working on my PC I'll upload some photos of what I did and how I did it into the FAQ

In the meantime, i have a car running on bike carbs that WORKS!

update

as some of you will know the head that was running these bike carbs snapped a valve after 130 miles

so I've now got a GT head in and is working fine although a bit rich when putting the power down.

Have got an appointment at PDQ tomorrow morning and will report back.

And I'm not running vac advance - although can do, with all four runners ready to connect to the dizzy. will take advice from the RR guys in the morning when the carbs are set up. and we will know once and for all whetehr its betterw ith or without, and if we can get it working.

Not possible mate.. if I do that I haven't got space for the filter. This will work perfect. And I'll probably be the only one running proper filtering with these carbs.

try lengthening the steel tubing so the silicone cant collapse then, the silicone will also soften with age and fuel ingress and the problem will worsen.