Bike Carbs For A Pinto

[Guest cryoman]

, would there be any difference performace in whether the carbs were from a 600cc bike or something nearer 1000?

 

is their a good online guide to the whole process of fitting them? (i'm just on the way out to look for PPC)

The 600 gsxr carbs have a choke of 36mm ish and the larger the engine the bigger the choke. I believe the gsxr1000 has a choke of 40mm (i think)

[Guest paul091085]

The more topics i read on here, the bigger my jobs list becomes! Have decided to give the bike carbs a try and have got some R1 carbs with a fuel pump and with a bit of arm twisting my brother has agreed to make me a manifold. Back home from uni in 2 weeks, so will let u know how i get on.

 

Paul

[Guest docter fox]

I tried to get hold of a copy of PPC today but nowhere had the right issue (although one had a copy from december)

I'd be very grateful if someone could scan it in and email me a copy

[Guest salty_monk]

Any bike card between about 38mm (600cc bike) & 45mm will be ok.

 

40mm is approx equivalent to 45mm Webbers.

 

I believe you measure them where they meet the manifold.

 

Dan

[Snapperpaul]

Q: Hiya, are these jetted and set up to suit or will they need setting up ? What sort of throttle linkage is required? Thanks.

14-Mar-06 

A: because these are of an SU type carb they respond to the air speed running through them. they may require a small amount of set up,

 

Interesting because in my early years with SU carbed cars the size was quoted in inches i think it equated to the choke size, also the tuning of the carb to the engine was done by a mixture of jet size and the needle profile.

 

Still a bit hit and miss but seems to work, throttle bodies and ECU more controlable.

 

have a look at this site about SU needles, Needle info if bike carbs use needles then there is a fair bit of tuning available.

[Longboarder]

The SU carb is 80 year old technology and if you look at a one from the 30's and one from the 80's you can hardly see a difference. The Japanese took the principal and made it work so well that carbs were retained on bikes long after fuel injection was standard on all their cars. The eventual switch to fuel injection on bikes was largely for emission reasons, not power or drivability.

 

Nigel

[Snapperpaul]

Do bike carbs with needles have different profiles?

[Longboarder]

No idea. Boggs just alter the jet size when they set them up for cars.

 

Nigel

[Guest MrSandman]

I have looked at the parts list for R1 carbs and only one needle is listed.

 

I will try bike tuning firms next as I am fairly certain that they will be available. It is highly unlikely that any carb will be fitted to only one engnie derivative so I guess other needles will be available.

The other option is to jet slightly too weak and then reprofile the needle with a needle file to get the desired mixture at each point of throttle opening. This used to work fairly well in my mini tuning days.

Some bike carbs have various slots in the needle to allow for slight up/down adjustment and variation of the mixture. I have not taken one apart yet to check but this is on my list of jobs to do.

Just the small matter of a respray and finishing the Megajolt install to do first.

[Guest MrSandman]

Mikuni Carb Set up info

 

This site gives some useful advice on which parts of the carb need adjusting to alter mixture at various throttle openings.

 

Also has a list of needles with measurements.

[Guest Kieran]

A lot of bike carb needles have 3 or 4 groves for a e clip to sit in. You can then alter the height of the needle for mid range mixture.

 

Kieran

[Guest vacinc]

A lot of bike carb needles have 3 or 4 groves for a e clip to sit in. You can then alter the height of the needle for mid range mixture.

 

Kieran

correct, have did quite a bit of tuning on quad"s 2 strokes, there is lots you can do with bike cards, move the circlip down one notch, file top of the slider, remove secondary idle jet and so on, but i"d leave it alone, and keep it simple, you can spend weeks tinkering with them babies,

[Guest paul091085]

finally got my bike carbs fitted over the easter holidays and just need them setting up properly now. Im thinking about booking a rolling road setup with bogg brothers, has anyone else had theirs done by them?

 

Paul

[Snapperpaul]

Show us some photos.

 

Boggs brothers seem to be the men.

Let us know what bhp you get and what other mods you have done.

[Guest paul091085]

dont have any photos with me at the moment, but will put some up once im back home in couple of weeks.

 

my engine is a 2.1 pinto with standard head with a lightened and balanced flywheel and bottom end.

 

Not sure what BHP ill get, dont know what its running at the moment either, so will be interesting to find out.

 

Paul