Honda CB750 Cafe Racer - EP11 - Murray's Carbs Install (It’s Alive!!)

In this episode of the 1992 Honda CB750 Nighthawk cafe racer build we install a carburetor kit from Murray’s Carbs. This let’s us start the CB for the first time and hear the new exhaust!
Using a Murray's Carbs Dual Mikuni VM34 kit we bring the Nighthawk to life.
Shown in this video is the first startup and a running clip after some minor tuning. The eBay/Amazon mufflers sound pretty good!
Items used in this video are:
-Murray's Carbs Dual VM34 Honda Nighthawk 750 Carb Kit

[@brudug713]

Thanks. You’re the first I found that went thru the entire installation. Didn’t want to order without seeing it installed.

[@ncv4708]

Glad the video was useful!

[@TommyFresh521]

Beautiful work!

[@ncv4708]

Thank you!!

[@TommyFresh521]

@@ncv4708 Where are you located? I want a CB750 Cafe Racer.

[@ncv4708]

I’m located in Maryland

[@TommyFresh521]

@@ncv4708 Just my luck. I am in Arizona.

[@CaptainMustardPants]

Also, where did you get those handle bar clips where the old fuse box use to go? Been looking around for them

[@ncv4708]

So I think only the 80’s CB750’s had the fuse panel on the handlebars. The 90’s CB750’s had them under the seat. Maybe the 90’s ones will fit?

[@CaptainMustardPants]

@@ncv4708 for sure man. I have a 1980 honda CB750K and been looking all over for those

[@jayweiner977]

Nice video I just picked up a CB 750 and pull these guys off and clean the carbs since it had been sitting for a full year. I was hoping you were going to show how to adjust the idle and Air screws but nonetheless awesome video.

[@ncv4708]

I did have to adjust the air screws in quite a bit. I believe these carbs are jetted quite a bit on the rich side.

[@jayweiner977]

@@ncv4708 in still figuring mine out for the most part. Hard to get this thing running perfect

[@CaptainMustardPants]

What speedo/tach combo do you have on that bike?

[@ncv4708]

It’s from Amazon for universal use. Item # B09SWQ1XKM

[@Coco-Crisp25]

Those little “pink” tubes on the carburetor just hang out? Great videos btw.

[@ncv4708]

Yup, those tubes are vent tubes that go to atmosphere. Thank you!

[@Loudyotaa]

I am building the same bike right now, and am tempted to go with these instead of rebuilding and jetting the old carburators. I see you rebuilt your originals, why did you go with these? How long did it take you to get them? Were they pretty much plug and play tuning?

[@ncv4708]

They start and ran out of the box. I adjusted them a little for better throttle response which I thought was needed.

[@brudug713]

I’m going to assume the entire stock air box is removed. Please correct me if I’m wrong

[@ncv4708]

Correct, the entire airbox has to be removed to make room for the Murray's kit.

[@MrKneeah]

Hey there, nice video! I am new to the motorcycle community and I don't have a lot of knowledge about carbs. I have a 1993 Honda CB750 and was wondering about this kits' amount of carbs. I assume the 1992 version also has 4 carbs. Could you explain if there is any difference in performance with using 2 instead of 4? Do each of the carbs you installed in this provide the same amount of fuel/air as two of the stock? Thanks for the help!

[@ncv4708]

So this kit has better performance, but uses more fuel. The factory carburetors function off vacuum (CV style) which meters fuel differently than the Mikunis which are a slide style that is directly connected to the throttle. The bike can actually burnout or wheelie now with the new carbs.

[@MrKneeah]

@@ncv4708 thank you for the explanation! I appreciate it.

[@ncv4708]

@@MrKneeah no problem!

[@lunatic9735]

is it possible to install one of these without moving 5o battery location on my 2000 cb750 nighthawk? it says on murrays carbs that you dont have to do any frame mods, but it seems having the relocate the battery is a pretty big task

[@ncv4708]

Unfortunately since the airbox is also the battery box (molded as one piece) I think you have to relocate the battery or hack the battery/airbox down to fit the carbs.

[@lunatic9735]

@@ncv4708 thankyou for the insight, been w8ndering if it was even possible for awhile. at this point idk what to do next besides jetting the current carbs then because im trying to not get too involved with adjusting the frame because ei dont have much experience and its my first and only bike.

[@eddiexplores]

I just picked up a 1982 Yamaha XJ650 Maxim and ik they are completely different but I have a quick question! Did doing the 4 carb conversion to 2 change anything of the bike? the sound or anything at all? They offer the conversion for my Yamaha to and want to know before I order!

[@ncv4708]

It didn't really change the sound, but it did make the bike rev quicker and actually make it capable of picking up the front tire since it got rid of the lag of the CV style carburetors.

[@fitzbro3023]

Is there a gap between the carb boots and the carb

[@ncv4708]

There is, but it's machined that way. They are fully seated though.

[@jamesgordon4754]

Not familiar with Murray carbs, are they better than Mikunis? Saw a build using Mikunis and the throttle was much more responsive and faster abviously. Did you need to rejet the Murrays?

[@deegan727]

They are Mikuni’s. What’s Murray’s is the 2 into one manifolds and the service they do to the carbs to set them up for you needs.

[@ncv4708]

Yup as @deegan727 said. They are Mikunis. You are paying for the carb set up and the special manifolds.

[@theleadfootgunner6804]

How did you delete the stock air box? On the CB650 I’m working on, the box is connected to the rear fender.

[@ncv4708]

This one was pretty similar. Since the rear frame was cut and a new hoop / fender and battery box was added it basically deleted itself. This ultimately led to changing to the Murray's Carbs as the stock CV type carbs do not like to run without the airbox.

[@theleadfootgunner6804]

@@ncv4708 I’m actually installing Murray Carbs twin Mikuni setup. That’s why I ask!

[@ncv4708]

@@theleadfootgunner6804 you won't be disappointed with them! I'm guessing you'll have to replace the rear fender or cut the airbox off to get rid of it and make things look clean.

[@theleadfootgunner6804]

@@ncv4708 thats what I figured was just trimming the stock box off. I appreciate the advice!

[@joshbethel5800]

Question. Is that a stock front rim with a fork swap? I'd like to do a fork swap but want to keep my wheel and brakes.

[@ncv4708]

It is. It's stock for the bike, just painted gold. Stock wheels too

[@joshbethel5800]

@@ncv4708 bolted right to your fork swap? Which forks?

[@ncv4708]

@@joshbethel5800 Oh no. No swap, these are the ones that came with the 1992 CB750 Nighthawk. I just rebuilt these and painted them gold.

[@Coco-Crisp25]

How come you decided to replace the original carburetor after putting cone filter on? Ty

[@ncv4708]

So CV carburetors do not function very well without the airbox. When the airbox is removed the vacuum pulses are disturbed and they will bog amongst other issues. So to make sure the bike would run 100% it was decided to go with traditional style carburetors.

[@Coco-Crisp25]

@@ncv4708 ty for the info. I’m doing the exact same bike and I don’t want to put that air box back in. I also don’t want to spend $700 or more on new carbs.

[@ncv4708]

@@Coco-Crisp25 They are a bit pricy I agree. There may be other solutions to get CV carbs to work without the factory airbox like a shared filter box. Most likely that will be a little expensive as well though.

[@Suzuki_drake]

Can’t get mine to run without it on prime any tips ?

[@ncv4708]

The air screw most likely needs adjustments. Google images has a diagram that will show you what screws are which. I had to make some adjustments to get this set to run right.

[@deywuson680]

Do you think it made a difference in the speed of the bike?

[@ncv4708]

The bike actually didn't run when I received it. Also since we were removing the airbox this seemed like the only option. However compared to bikes with CV carbs I've ridden, the Mikunis have MUCH better throttle response, it's zero lag.

[@shelbyhilliard8677]

Did you have to upgrade the ignition

[@ncv4708]

Nope! Factory ignition works fine with these carbs.

[@nyronalli9750]

How can I get this for my 750night hawk 1992

[@ncv4708]

Murray's Carbs can be found on Google. The carb kits cost about $700 but work directly out of the box.

[@therealyoungfue]

What kind of tank is that

[@ncv4708]

It was an eBay tank. It took a bit of work to get it to fit.

[@clintbeeler5069]

How has it felt riding it since install?

[@ncv4708]

The bike is way more responsive than a CV setup, absolutely zero lag. However out of the box these carbs are jetted a bit rich so fuel economy is awful now.

[@clintbeeler5069]

@Nick Vincent fuel economy is on the absolute bottom of my list of priorities so that works lol. Any difference with your butt dyno?

[@ncv4708]

@@clintbeeler5069 I don't really have a before since the bike wasn't running. But from similar bikes I consider how much difference the response is from takeoff a huge one. CV carbs are just generally more laggy.

[@czortorys4401]

That's new.

[@ncv4708]

I never heard of Murray's Carbs until someone told me about them. It seemed like a really cool idea. They definitely perform too.

[@user-oc2kk9zh6k]

Main jet and pilot jet number? Please🙏

[@ncv4708]

I actually never opened these carburetors up upon receiving them so I don't know what size jets are in them.

[@runeankernielsen6264]

@@ncv4708 in case you do i'm curious as well