Injectored or carbies

[Savtec]

Hi guys, im in the process of building another engine for the ke, the block and head is sorted just wondering what i should use for intake? Injected or carbies?
whats the pros and cons of both?
Any help here would be good
cheers Gav

[slydar]

it basically comes down to who you know and your experience. there is no denying carbs can work, and work very well. but the tuning is somewhat less straight forward than efi.

you either need experience, or to know someone with a lot of experience to guide you. if youve got that, it can work out a fair bit cheaper than efi.

[Savtec]

yeah, that is what i was think, my dad is a carby king, so im thinking i might go that way,

[Jonny Rochester]

Carby king as in a 4 throttle setup, and he has a selection of different jets, both airs and mains? Or king of the old Sigma? It sort of makes a difference.

[Rian]

i think carby will work out cheaper eaither way.. and will sound a shit load better..

keeping them in tune will suck.. but jets and the like a cheap as chips.. and its cheaper to get a tune on them then on an aftermarket ecu i believe.

go that way.

[Hen may possibly be a nut]

^^^^ That entirely depends who you know.

Carbies can be easy and cheap if you have experience with them, parts lying around and can tune them/your dad can tune them. If not they can be expensive.

EFI can be easy and cheap if you have experience with it, like electronics and have some wires and plugs lying around. If not it can be expensive.

In either case the tune is very important and can cost you a fair bit and/or your motor.

Pick whichever you are more comfortable with. I'd tend to lean toward EFI as you can play with more parameters to make sure you get the right fuel and spark all the time, part throttle, hot days, cold start etc etc.

Hen

[Vance]

im lazy. i cbf changing the fuel system in a carbie car to suit a new injected engine.

go carbs. the sounds will blow your mind

[shift_rook]

i prefer efi, newer tech, end, carbs can look and sound better but, quads can sound just as cool on an efi setup

[Savtec]

Cool thanks for that guys also, what carbs to look for and what to stay away from?
IM thinking about motor bike carbs, short fast throttle response :shocked:

[slydar]

they can all work.

webers are the easiest to set up. simply because of parts availability and the fact that a lot of peopple are familiar with them.

delortos and mikuni PHHs a close 2nd. thought parts are harder.

as far as bike carbs. its not that simple. you dont just pull the carbs off any old bike.

most bike carbs arent really "tuneable". the ones you see jap 86 dudes using are usually either Keihin FCRs, or Mikuni RS. both are aftermarket type carbs (a few bikes did come with fcrs, but very very rare).

theyre awesome. but.. not a lot of know how out there. also.. not cheap. youre not likely to get even a 2nd hand set for less than a grand. especially now the $ has dropped.

[af300e]

Yeah agreed, the flat slides (fcr) are the ones to go for. I've tuned a few of them (keihins) as singles on dirt bikes and they seem wonderfully tunable although race bikes can be allowed a little less user friendliness when it comes to driveability. They are known to buck and fart a little at lower throttle openings even with a great tune. Whether the extra inertia of a car would have a significant negative effect on driveability I don't know. At a guess I'd say it will.
That notwithstanding, fcr's would be my personal choice due to experience/knowledge in tuning.

Any bike shop worth its salt will carry a good range of jets, slow, main, leak and the better ones even carry an array of needles with differing tapers. A bike dyno tuner will have the best range naturally.


I think I remember seeing them advertised new for close to $2000 a little while ago in bike trader.