45 replies to this topic

[Surestick]

If you can fit the stock airbox between the carbs & the firewall you could use the stock filter or K&N version thereof.

Look at the pics on this page. The guy that built it is an RPR member & posted it a while back.

[lilneedle]

I was wondering if these cbr600 keihin 32mm carbs are gonna give me power....a guy from a carb place told me to find my flow in my engine somehow he said to find your bottle cap of flow or sumthing???i didn't get it and something bout a flow bench....I just want these to work good when I get them on my 1.5...help...TOM
p.s anyone used 32's or 600 carbs??

[Surestick]

I think you mean bottle-neck...
What the guy meant was that you should find the most restrictive part of the intake/head/exhaust system & modify that first then the next most restrictive & so on.


On a stock carbed motor that is most likely the stock carb & to a lesser extent the downdraft intake manifold so yes, the bike carbs, if properly jetted, should give you a pretty big improvement.

[lilneedle]

Heard or 32 being run????I'm just worried they are to small.....TOM

[juliansavino]

Heard or 32 being run????I'm just worried they are to small.....TOM

<{POST_SNAPBACK}>

dont worry about it, if you feel they are to small after you install them then put em back on ebay, and buy new ones, i have a pair of mikuni 40 phh's in the mail headin my way right now. i cant wait to get em, if you truly want alot of gains ive heard your best route is either the mikunis im gettin or the webber dcoe 40's. also dont quote me on this but most the people using motorcycle carbs i belive go with 36's or 38's. and to get the most out of the carbs your still gunna need a better flowing exhaust, and maybe a cam upgrade. also a good p&p job is a must. Total flow products will give you a full stage2 p&p for $800.

[Surestick]

Depends on the power you want to make.
Most 600s are making about 100 hp so the carbs are good for that if not a bit more with a change of needles to flow more fuel. I suspect you are probably looking at quite a bit more than 100hp before they become what's holding you back. I don't have any numbers to back this up but w/o a ported head & race exhaust you will most likely be more than ok w/600 carbs.
Most 1000cc sportbikes are at ~120hp & would be the same as above...

With a fixed venturi carb (like a Weber DCOE or pretty much all downdrafts) the size of the venturi is important. If it's too small it becomes a major restriction & limits power, if it's too big the carb becomes hard/impossible to tune properly as it's not getting enough vacuum signal.
With a CV carb like most motorbike carbs this is less of an issue. Unless you are using grossly undersized carbs (scooter carbs or something) the carb will adjust the venturi size to match the airflow. You just need to find a set of needles that give you the right mixture for your motor's needs. Most likely you will be off in the top end, either lean or rich depending on the motor the carbs came off of, but ok everywhere else.

[phatboycrxhf]

Depends on the power you want to make.
Most 600s are making about 100 hp so the carbs are good for that if not a bit more with a change of needles to flow more fuel. I suspect you are probably looking at quite a bit more than 100hp before they become what's holding you back.  I don't have any numbers to back this up but w/o a ported head & race exhaust you will most likely be more than ok w/600 carbs.
Most 1000cc sportbikes are at ~120hp & would be the same as above...

With a fixed venturi carb (like a Weber DCOE or pretty much all downdrafts) the size of the venturi is important. If it's too small it becomes a major restriction & limits power, if it's too big the carb becomes hard/impossible to tune properly as it's not getting enough vacuum signal.
With a CV carb like most motorbike carbs this is less of an issue. Unless you are using grossly undersized carbs (scooter carbs or something) the carb will adjust the venturi size to match the airflow. You just need to find a set of needles that give you the right mixture for your motor's needs. Most likely you will be off in the top end, either lean or rich depending on the motor the carbs came off of, but ok everywhere else.

<{POST_SNAPBACK}>

wow that is some good info makes me wanna do it now thnaks for the info even though it wasent meant for me

[lilneedle]

Well... I got the bike carbed motor running today...its running weird...vac advance is not hooked up,intake/exaust man. gaskets were reused for now,missing a few studs for exaust man. and just running the down pipe..what yall think here???she was idling sorta low early one then it idles high now...and I cant get a full and smooth rev..what yall thinks going down here????

[Shinobi's_Underwear]

Are you running filters yet? They cant be drawing from open air or you will get slide flutter and weird popping backfires (and very random idle quality). Bike carbs need a filter for a vacuum reference. Let me know, and we can go from there. Later dude.

[jjamiemmark]

we need video?????????????????????????...

[Shinobi's_Underwear]

Sorry if it takes forever to reply. I'm switching everything over to wireless and the only thing I have working is my PSP. I suck at texting, this took 20 minutes.

[lilneedle]

Its all good...so what to do about the vac advance????booster????and are you sure ya can't run witout filters...what would be the best,quickest,affordable route for solving that????also there is no ajustments on these keihins is there...just jets...how will I know how to dial them in good???i'z stumped...TOM

[ibcnya]

Hello all...Me and my boy cyrus(1rstgencrxlover) when to the yard and dug up a si intake today...then we cut and modded it at his job..as you can see I plugged the injector ports with ep-200 epoxy..luv that stuff!!!
All in all this cbr600 carbs project is comming along...now all I need is a si head,and an electric fuel pump....I hope..lol
What yall think...any input on this project ???TOM

<{POST_SNAPBACK}>

where do you hook up your line for your brake booster....?

[lilneedle]

I didn't ...but you can use one of your injector intake ports....some people have used tire valve things...they seal it in there with expoxy or sum. The u remove that little valve out of it and hook a vac line to it...or just drill and slap a vac source somewhere inthe middle...let me know if this helps brother...thanx..
TOM

[ibcnya]

I didn't ...but you can use one of your injector intake ports....some people have used tire valve things...they seal it in there with expoxy or sum. The u remove that little valve out of it and hook a vac line to it...or just drill and slap a vac source somewhere inthe middle...let me know if this helps brother...thanx..
TOM

<{POST_SNAPBACK}>

yeah thatll work...not that i have bike throttle bodys or thinking about trying it