Anybody with a decent knowledge on carbs?

[ducatilover]

I am thinking what size jets to go to on the spada to try run an open carb set up. I was thinking of spacing the mains up? I cannot find what size the standard jets are [100-105 would sound right to me]
Any ideas? There is no information around on modifying these toys :pinch:
Would a 130 main jet be too big?
I have attached a piccy of the carbs.

[The Pastor]

picture fail.

on my mc22 i went with a 145 jet on open carbs.

What bike are you talking about? with no airbox you will lose all your bottom end power.

[ducatilover]

picture fail.

on my mc22 i went with a 145 jet on open carbs.

What bike are you talking about? with no airbox you will lose all your bottom end power.

The spada. I will try un-fail the picture

[The Pastor]

the only way you'll know is either trail and error (hard to do) or on a dyno with trail and error (expensive).

the air will be getting pretty choppy coming into the carbs, i still have my lower bitof the air box attachd, and the velosity stacks, without them it cut out at 14000 rpm.

[ducatilover]

Sadly I don't have as much dyno access now. I might try doing the jets and retaining the air box then.

[The Pastor]

I think its best to leave the airbox on but take off the air filter.

but gettting the right jetting is really hard to do. its guess work.

[ducatilover]

I think its best to leave the airbox on but take off the air filter.

but gettting the right jetting is really hard to do. its guess work.

That's how it is at the moment, 34rwhp isn't bad for a 250 twin. Never seen more actually. I want to fuck with it though;)

[The Pastor]

oh yeah totally. messing with bikes is fun. just remember that the bike designers know what they are doing, and they have put effort into getting the air box right.

[ducatilover]

oh yeah totally. messing with bikes is fun. just remember that the bike designers know what they are doing, and they have put effort into getting the air box right.

Yeah that is why I wanted to ask about it;) But there is always a compromise. E.g the exhaust system on the spada is a dirty big fat compromise :crazy:
I am not so worried about low down, just want to see what kind of power I can find before the new hairdryer set up is finished. Speaking of which, I got the intercooler in the garage now. :woohoo:
Perhaps I should wait to do the cams before the jetting?

[The Pastor]

jetting is easy to do, and it will take a while to get it right. so keep trying

[ducatilover]

Well, why the hell not. I get the jets for free.:woohoo:

[The Pastor]

Well, why the hell not. I get the jets for free.:woohoo:
what????? hook a negro up!

[ducatilover]

what????? hook a negro up!

My old man is an engineer;) I can just throw old jets at him and scream "DRILL IT BAY!!!!" basically :whistle:

[The Pastor]

My old man is an engineer;) I can just throw old jets at him and scream "DRILL IT BAY!!!!" basically :whistle:
hey! i wanna do some work on my rear subframe, could he help me out? i'll give you the frames for free?

trick is i really wanna learn how to do it myself - i just lack skill and tools.

basicly i've cut my rear subframe in half - want to make the cut square and the same lenght both sides then welding in a small bar.
http://www.kiwibiker.co.nz/forums/picture.php?albumid=14&pictureid=23269
http://www.kiwibiker.co.nz/forums/picture.php?albumid=14&pictureid=23268

If he would like money or beer, ive got a bit of both!

[ducatilover]

hey! i wanna do some work on my rear subframe, could he help me out? i'll give you the frames for free?

trick is i really wanna learn how to do it myself - i just lack skill and tools.

basicly i've cut my rear subframe in half - want to make the cut square and the same lenght both sides then welding in a small bar.
http://www.kiwibiker.co.nz/forums/picture.php?albumid=14&pictureid=23269
http://www.kiwibiker.co.nz/forums/picture.php?albumid=14&pictureid=23268

If he would like money or beer, ive got a bit of both!

I will have to ask him, He may be a bit busy and I think it would be better to get somebody local to you to do it? We are all the way in eketahuna and the work would get done in wellington. I have a few mates up here who could help hopefully

[The Pastor]

oh ok, no worries mate, just trying to find someone who can let me use their tools.

its my bike, and im the only one who gets to work on it ;)

[ducatilover]

oh ok, no worries mate, just trying to find someone who can let me use their tools.

its my bike, and im the only one who gets to work on it ;)

We don't have much equipment for welding here at home sorry bro. May I ask why you are doing the subframe mod?

I will have to let you know closer to saturday if I can come up, Mum has her pre-op this week and I may be taking her for the op on saturday. Hopefully I get to blat up to hastings. Poor spada needs a good run, it's been half a day since it got one.....;) I am hoping the fairing mount will fit, The cbr have triple clamps that taper fowards and mine don't to the same degree

[The Pastor]

why? because i can!

[ducatilover]

why? because i can!

Sound like everything I have done to my bike. We would make a good team "2 stroke v7 125? why guys?"
Coz we fuckin want to!" :woohoo:

You must let me ride the mc22....

[The Pastor]

Sound like everything I have done to my bike. We would make a good team "2 stroke v7 125? why guys?"
Coz we fuckin want to!" :woohoo:

You must let me ride the mc22....
only after 25 beers!

[ducatilover]

only after 25 beers!

Dammit! How about you out run the spada and I sit there making a cup of coffee while I try push past 175 [fucking high profile tyre]:crazy:

[Brian d marge]

put the tools down and stand clear off the bike

the bike needs cool still air in order to breathe that's why the air box is there, there is some good gains in power with a properly designed airbox


Jets , you can drill emm , but they are designed for fuel flow

its a spada, sell it and buy a 600 , put the factory plastic in a bag and keeep it safe , replace it with a race fairing ,,, donnt kill yourself have fun


Stephen

[ducatilover]

put the tools down and stand clear off the bike

the bike needs cool still air in order to breathe that's why the air box is there, there is some good gains in power with a properly designed airbox


Jets , you can drill emm , but they are designed for fuel flow

its a spada, sell it and buy a 600 , put the factory plastic in a bag and keeep it safe , replace it with a race fairing ,,, donnt kill yourself have fun


Stephen
I understand what you mean stephen, but I am doing these silly things out of curiosity. To create something that interests me and to provide a challenge. Also, I am going to agree on the air box statement.
Have you got any suggestions as to spacing the jets? ;)

[imdying]

Give something like this a crack (http://motorcycleinfo.calsci.com/Airboxes.html), then jet to suit.

[ducatilover]

Cheers mate!:niceone:

[Brian d marge]

I understand what you mean stephen, but I am doing these silly things out of curiosity. To create something that interests me and to provide a challenge. Also, I am going to agree on the air box statement.
Have you got any suggestions as to spacing the jets? ;)
Rotten phone
I had a message typed out and it dissapeared
I use openfoam to look at air flow through airboxes ( just been looking at the airflow through my bathroom)
When you say spacing the jets do you mean putting a spacer under the needle or choosing the correct jet size for the gear and throttle position

Stephen



When you say spacing the jets, do you mean choosing the jets for the gear and throttle position or adding a spacer under the needle to lift it
I use open foam and netgen to look at airflows through airboxes, though my experience is limited

Stephen

[Brian d marge]

Give something like this a crack (http://motorcycleinfo.calsci.com/Airboxes.html), then jet to suit.
Friend of mine has just done this on his enfield single and. Reports a strong improvement on the midrange he had to jet up a bit
Downside being the tuned length of the snorkle is eeer long when I get home I'll post a photo

Stephen

[ducatilover]

When you say spacing the jets, do you mean choosing the jets for the gear and throttle position or adding a spacer under the needle to lift it
I use open foam and netgen to look at airflows through airboxes, though my experience is limited

Stephen

Adding a spacer to lift it.:whistle: