I tried tuning emulsion tubes, under the theory's iv read on the net.

Ie, holes nearer the top of tube effect lower rpm/throttle, like lower needle position, thus less holes = less air = richer.

Kinda didnt work that way at all ahah

Interesting. I'm going to have a look to see if mine are blocked then, as its stupidly rich (as you know!)

Mine wernt blocked as such, i connected them to the return line which clearly had some sort of large effect lol.

did you send your carbs to bogg bros to be stripped/cleaned etc?

Did i fuck!

I had my breathers connected to eachother at some point and it wouldn't run at all well! The fact that only one set is now overflowing says to me there's an issue somewhere. Especially as it was happy to tick over for ages lasy week

Blocking emulsion tubes is brutal. There are various differerent ones allowing you to change emulsion rates if you're a bit out of zone.

Mine are custom, i took a set with less holes and narrower bore which slashed my emulsion too far down, drilled the bore back open a fair bit to reduce fuel speed and allow more emulsion back into play, still less than before.

I did this because i felt that 170 jets were too far away from standard but i didn't wanna block the jets - now down to 145.

I tried playing with emulsion tubes and didn't really achieve much tbh, mine works, is reliable, faster than cars with more power and economical enough if you drive it economically, therefore it maybe brutal, but I don't care haha

I have no wiring loom in my car atm, and was just wondering if there was a quick and easy way to just rig the car up to start or this is complicating things?

Just plugging the fuse box in and just wiring in the needed plugs and mk2 ignition?

Let me know if this is a pointless excersise haha

Non at all ? Not even headlight loom ?

If not .. Wire up a relay to the fuel pump and coil live, then just have a switch .. Flick that, Turns pump and coil live ..

None at all mate, the harness i have is in AN awfull way with cut wires and loose connectors!

Is there anyway i can use the 1ltr wiring loom and plumb into the mk2 ignition system....

I've just about finished putting my freshly rebuilt AFH with CBR600 carbs and a Bogg Bros manifold into my mk2 saloon. Had a tinker this afternoon and I found that the engine starts pretty well (Vac adv disconnected and plugged) but will hang on to revs and sometimes increase revs with no pressure on the throttle. Shit me up when It did it as the engine has all new bearings, rings, etc.

If you rev it to say 2k rpm and take your foot off the throttle, the engine will keep revving to 2.5 - 3k, then slowly drop revs until the engine cuts out.

It has jets drilled by Bogg to 1.5mm. Fuelling is via the CBR 600 bike pump, no return line (pump cuts in when needed from back pressure).

I've set the timing to the "Z" mark as per factory settings, but at this stage I've not balanced the carbs together as I need to buy some kit for that. The throttle is definitely snapping closed looking at the throttle wheel...

Anyone seen this before?

Edited 16 December, 201213 yr by Vic

Simon had a similar issue, had the same with my friends car too, even though his throttle was snapping shut an extra spring helped it.

Ignition could probably be advanced a bit more if you're not using vac advanced,

Balance will help too, have you had a listen to each inlet to see if the sound of the air flow into each varies much?

Id recommend getting the carbs balanced too. There isnt much point trying to tune them untill this is taken care of mate

One minute they can be idling and revving up sweet, restart the engine and its way off again.

Also triple check that seal and gasket is air tight.

Thanks a lot for the advice. I'll try the throttle wheel spring first. I'll try balancing carbs like you say, I can go over them again when my vacuum kit arrives. Tried various timing positions but seemed to make little difference to the revs hanging on. Will have a tinker tomorrow!

Yeah, definantely worth checking for air leaks (lost ability to spell)

On mine I put an extra return spring on the throttle wheel and also on on the throttle pedal

Only takes a small air leak to cause a great deal of messing about and chasing your tale.

Id recommend checking for;

1. Air leaks with a suitable solution in a squeezey bottle, snoop etc

2. Balancing

3. Timing/mixture

Had a good look at my setup today and have it running very sweetly now, the idle adjustment was all the way out meaning that the car was trying to idle on the main jets. The throttle wheel IS sticking, so it needs an additional return spring. Starts on the button now and idles so steadily, dab of welding and a carb balance then i'll be on the road.

FAO Max, however useful to others.

This is a spare set of carbs where the air jet is blanked. This takes away the air supply to the emulsion tube which makes it a lot richer (it made mine over 40 main jet sizes richer)

These can be soldered up with silver solder.

Was trying to find this out before, getting an AFR for xmas, so starting to read about these.

But if you solder them up, how d'you get them out if you don't like it? Might look at machining a cap or something, good bit of info to have though. Searched for ages but couldn't find anything.

Mine arnt soldered up - I have proper blanking caps that come on some bikes standard

Yeah, tried to search for them too, couldn't find any. :( I'l phone around.

When experimenting, i used matches to block the air jets. As i said before though, i ended up using more restrictive emulsion tubes instead, as i wasn't happy with the economy commuting when blocked.

You can sleeve the emulsion tubes for the same effect - partially sleeved to block however many holes you like, or fully sleeved for complete blockage (same as blocking the jet itself). Simply warm some nylon airline and wedge it over the emulsion tube.

Yeah mikey, I gave up with emulsion tubes haha, I read up on them and blanking certain areas should effect certain bits, but in the end it didn't really seem to work out for me.

I know from an emissions/economy/atomisation point of view blocking the emulsion tubes isn't a good idea, after all them holes are there for a reason hey!

Just worked for me, yet in other cases, such as a friends car it just didn't work out and much larger main jets were the answer

got a question for you guys, decided to carb my 1.3 mk 2 coupe, pretty new to this so been doin some research to try find out as much as possible an i see the best carbs to use are 600cc on a 1.3. got a set of carbs off my mate for free, they're off a ninja but he doesnt know what cc bike it was. they're 38mm bore. if i was to ensure the main jets are the right size is there any reason as to why these wouldnt work if they are off something other than a 600cc bike? also roughly what size should the main jets be to get it up and running untill i can get it to a rolling road?

sorry if anything iv said is noobish like i said I'm new to this just trying to learn

any infomation will be appreciated, cheers :)

Can you take a picture of the carbs so i can try to narrow it down?

Just as a warning if there off a kawasaki then your main jet might be a lot bigger than the people running CBR's.

With Kawasaki carbs your ideal main jet would be in the 160+ range (trust me mine are 180's). Of course this does depend on manifold, and other engine mods.

Can you take a picture of the carbs so i can try to narrow it down?

Just as a warning if there off a kawasaki then your main jet might be a lot bigger than the people running CBR's.

With Kawasaki carbs your ideal main jet would be in the 160+ range (trust me mine are 180's). Of course this does depend on manifold, and other engine mods.

http://i1276.photobucket.com/albums/y480/v...zps6a6a0488.jpg

http://i1276.photobucket.com/albums/y480/v...zpse046e650.jpg

http://i1276.photobucket.com/albums/y480/v...zpsdfb6f455.jpg

pics are in photobucket dude, links above. cheers :)