can anyone tell me what make the cbr600 carbs are as in are the mikuni or keihin. also while I'm at it what make are the r1 carbs? i know I'm going to need to re jet whatever i get so just wanted to see which it is easier to get bits for

can anyone tell me what make the cbr600 carbs are as in are the mikuni or keihin. also while I'm at it what make are the r1 carbs? i know I'm going to need to re jet whatever i get so just wanted to see which it is easier to get bits for

My cbr 600 are keihin but can't say for any others.think they are roughly 2000 model or there abouts

Does anyone actually have any power figures for a carbed Gt? Not sure if its worth shelling out and doing mine properly and getting it on the rolling road... Coupled with 4 branch, 268/268 cam, p+p head, full stainless system be looking at a steady 100bhp?

or would it be going backwards in terms of tuning?

does any one have any idea which bike carbs have a 40-41mm diameter bore? cbr900's are only 38mm not realy big enough for what i have planned and yes 41mm will run on a gt

Does anyone actually have any power figures for a carbed Gt? Not sure if its worth shelling out and doing mine properly and getting it on the rolling road... Coupled with 4 branch, 268/268 cam, p+p head, full stainless system be looking at a steady 100bhp?

or would it be going backwards in terms of tuning?

well last week my gt with gt cam, p+p head, 4 branch with 2" system on ecu to control ignition was 90bhp at the flywheel and 70bhp at the wheels

1 week later with mk2 ignition was 87bhp at the flywheel and 66.9 at the wheels so you aint going to hit 100bhp with those mod unless mine is an spi block which was bought as a gt lump

Does anyone actually have any power figures for a carbed Gt? Not sure if its worth shelling out and doing mine properly and getting it on the rolling road... Coupled with 4 branch, 268/268 cam, p+p head, full stainless system be looking at a steady 100bhp?

or would it be going backwards in terms of tuning?

well last week my gt with gt cam, p+p head, 4 branch with 2" system on ecu to control ignition was 90bhp at the flywheel and 70bhp at the wheels

1 week later with mk2 ignition was 87bhp at the flywheel and 66.9 at the wheels so you aint going to hit 100bhp with those mod unless mine is an spi block which was bought as a gt lump

Well my gt is supposed to be running 103bhp, (kerrlys old one now with p+p head and dewedged tb) so i dont think i will bother going down that route!

well iv just looked at my rolling road print out and the fueling is correct but their is not enough air gettin in its suposed to be 14:1 14 parts air to 1 part fuel and mine is running 12.7:1 so i think i need those bigger carbs as my ports are rather large compaired to if you bought a p+p head

38mm are more than big enough for any 1.3, the CBR600's are 36.5mm and are fitted to Max_crox's 128bhp 1.4 16v as well as my 1.6 16v.

900's are good enough for a 2.0, so I'm sure they're okay for a 1.3. Especially given the valve sizing of the 8v small block Polo engine..

If you're not getting enough air through the carbs,its probably the opening rate of the flat slide throttles. Different springs are available,though i doctored mine. These also control the needle opening,so the jet sizing will have to be re-evaluated too.

Don't believe I'm asking this but cant remember this covered anywhere but where do people feed from for the positive side of the coil? Fuel relay?

just wired in everything and realised that i had no positive feed

Edited 4 April, 201016 yr by Cymro

i take mine from the black wire from the ignition switch, but you can use a direct feed from the battery if you fit a relay in place which takes a signal from the ignition switch (again the black wire) to tell it when to turn on.

in both cases make sure you fit an inline fuse and ideally an inertia switch

just stuck a set of carbs onto another afh 1.4 16v today (tezmc's)

so out went the fuel rail, dizzy, egr valve, coil and inlet manifold.

plumbing in fuel lines is simple only two inputs going to the existing fuel rail, tee pieced those together and fit the overflow line of the t to the carbs.

fitting the mk2 dizzy amp, loom and coil is simple enough, mk2 coil holder fits in place of the afh coil, ignition amp sits nicely next to the suspension turret, black wire goes to the battery negative, green wire to coil negative, black to coil position (all wires from the mk2 ignition loom only)

feed for the new coil taken from black wire from ignition barrel switch, fitted with inline fuse 15A.

no wiring cut on the 6n loom at all bar splicing the ignition barrel black wire, so can convert back to fuel injection easily.

didnt use the facet pump in the end, will have to get an inline fuel pressure guage to check what the system is running with the t-piece overflow self regulation.

filed mk4 throttle cable down but it got too weak and snapped, so fitted bike throttle cable, what an absolute pain in the arse getting to the throttle lever is with the pedal box, lower dash compartments and steering column, finally by some stevie wonder fumbling n the dark and the use of a cable tie, the throttle cable is fitted, however the lack of the following piece, led to the downfall of not being able to drive the beast home for young terry.

http://www.fastroadcars.co.uk/shop/index.p...mp;productId=54

but it sounds sweet as a nut, will be good to get it sorted and hear another afh on bike carbs blattin it around manc since humer/antoni's afh'd loon left for daaarn saaarf

oh forgot to add, the oil pressure light wsa on but wasnt before the swap, might be an ecu kicking up a fuss because of various sensors, but as its probably a chain driven pump, it'll be reet

Edited 4 April, 201016 yr by grungeisdead

i take mine from the black wire from the ignition switch, but you can use a direct feed from the battery if you fit a relay in place which takes a signal from the ignition switch (again the black wire) to tell it when to turn on.

in both cases make sure you fit an inline fuse and ideally an inertia switch

Ta.

literally pre-fitted all the wiring, coil & amp and thought i should test the coil and then thought shit where do i get the positive from

so just ran a wire straight to the battery to test the dizzy and coil. ill most likely run it off a relay with a direct battery feed, but will be looking at the haynes to see if its possible to take the relay signal off something in the bay.

What igniton setting have you guys found runs best?? Satndard is 10-12 degrees i believe. I am at the trial and error stage. Also spark plugs are tanned colour at high rpm but black at low rpm. Do you think i should lowwer the needle to lean the mixture or make the air pilot jet bigger???

What igniton setting have you guys found runs best?? Satndard is 10-12 degrees i believe. I am at the trial and error stage. Also spark plugs are tanned colour at high rpm but black at low rpm. Do you think i should lowwer the needle to lean the mixture or make the air pilot jet bigger???

Its leaning out at higher rpm so its possible the needle profile isn't ideal. This is a bit of an issue with the current stage of development regarding bike carbs on cars,but different needles are available.

My needles have a step of profile in them,are designed to open up the fueling considerably once past the midrange or under heavy labouring,but my other set are consistently progressive. They gave me the problem you have though,not opening the jet up enough top end.

However,it does sound most like the opening of the flat slides is a little premature in your case,causing low revs to get too much,and yet give correct fueling once the engine demands they're fully open. Worth checking (stretching the diaphram springs like i did is a pikey method to tighten them,yet still requires great care to ensure they're all perfectly matched).

I have actually cut a few coils out of the springs so they open fully under full throttle. I am running mukuni's and the air mixture screw adjusts the amount of fuel and flow from idle-1/4throttle. So i have re-adjusted it and gunna give it a run

right, bit of an update. throttle linkage adjuster turned up, so me and saf set about getting the throttle working yesterday.

it now returns ok, not perfect but it'll do for now!

2 new issues that we noticed.

at first, petrol was leaking from the breathers on the back of the carbs. we thought this might have been because the floats were too full after the car failing to start a few times? petrol also seems to be spitting out of chamber 2 on the carbs every so often.

we are running the carbs off of the standard 6n fuel pump with the carbs being fed from a t-piece and getting the backpressure from the main fuel lines.

also, we noticed some oil spitting out of the exhaust. i connected up my oil pressure gauge and it was reading 70 psi :s

any ideas guys?

cheers again!

What pressure you getting from the t-piece to carb line?

Could be too high a pressure to the carbs causing it to blow out the overflows.

High pressure like that could point to another problem, someone mentioned that it points to worn piston rings, but it could be a blockage or dodgy pressure valve.

ant came over and we took the carbs apart, and the back plate (float covers?) screws were mega tight with one of the nipple things snapped and leaking fuel, one was cross threaded, inside they were tres dirty, all of the needles and jets were mega tight, one of the needles was cross threaded so we darent take it out, but whipping out the other three needles, they were very dull in colour, and the holes themselves were full of crud.

suffice it to say, the carbs have seen better days!

we dont have a fuel pressure guage, and its running a t-piece back to the tank, but now with a filter king low pressure regulator, although i personally think it would benefit from a high pressure reg then low pressure reg, then t piece, as the standard valver pump buts out 2 bar pressure apparently!

but we managed to get it running without spraying fuel everywhere once we regulated the fuel flow to an acceptable level, but tez just needs to get some new carbs and hopefully he should be smiling with glee!

aye, new carbs are ordered and should be arriving today! i went for a bit of a run out on saturday, but noticed i had a bit of a fuel leak on the high pressure side of the regulator. might just have been the gash jubilee clips i had though. got some proper ones and going to replace it after work tonight.

it seems to be running ok with the shagged carbs as long as you dont go anywhere near full throttle

i'll see how i get on with the new carbs, and get a high pressure reg if needs be.

win for brapping it about =D

aye, will be mighty pissed if i've not got some shiny new carbs sat at home for me tonight! got back and realised i had a pool of fuel next to my alternator haha. close call really. tonights plan of action is hopefully fit new carbs, solder + heatshrink wiring and fit my omp wheel

I have two sets of carbs

1995 CBR600 FS/FT - Jetted as 144/142

1999 CBR600 FX - Jetted at 134/132

FS/FT needle on the left, FX needle on the right

the FX needle in the picture above still has the jet fitted in situ.

you can see the FS/FT needle is very dull, it should be bright and shiny like the FX's.

The carbs I have been running since November have been the 95 model, which I believe Max_Crox is too. His have been set up by Bogg Bros however.

I think Mikey is currently running FX's on his 1.6 16v hybrid but I may stand corrected.

My carbs currently sound wet when accelerating and i think it is running too lean, and has a lumpy idle like it is mildly cammed however thats probably attributable to the mismatched jets.

I'm going to play with jets this weekend and i want to fit into the fs/ft carbs - 4 x 144 jets, fx needles (as they are still nice and shiney) and see how the car fares.

might buy a set of 4 x 150 too and clean up my fs/ft needles as they were matched to the 144 jets.

would it be detrimental fitting the larger jets to the fx's needles, considering thier original jet size was 132/134

Superb link about setting jets, needle heights and idle speed

Edited 22 April, 201016 yr by grungeisdead

found this interesting bike carb rebuild specialist in manchester

http://www.nrp-carbs.co.uk/index.htm

just dropped them an email and hope to pop in and see them tomo or saturday.

doh they are emulsion tubes not needles, that place in manc stock all knds of jets 4 quid each, couldnt get in today as i got stuck in standstill motorgay traffic =[

slowly building my gt again properly on crb600 carbs, at the min I'm using the standard gt inline fuel pump but not sure if this will be ok. ill be putting an abd in soon but having all sorts of issues with the filter king reg aswell. any advise on the best fuel pump setup to use, facet ect and the best pres reg. cheers