CB450 Carbs on a CB360: Taking carbs apart and cleaning

[krukster86]

So when I purchased my bike last year it was sort of a Frankenbike. 80% CB360 with CB450 forks and carburetors. I have been running into problems with one of my floats, and I think my idle jets and bowls need cleaning (sputtering/slight hesistation in power when riding, bad idling and stalling at stoplights). I have been putting this task off for so long but this weekend I think I will pull the carbs, take some of it apart and clean it. I am totally new to cleaning and taking apart carbs so I have 3 questions:

1. Are there any great step by step guides out there for CB450 carbs? I have a service manual that walks you through it, but without a lot of pictures.

2. Are there any special considerations for the mismatched carbs that I have to consider in this process?

3. Someone told me that when I am taking the carbs off, to leave them with the rubber boots on since old rubber tends to crack easily, and just remove the ENTIRE assembly from the engine. Is this true? I thought I could just use a heat gun to loosen them up.

Thanks in advance!

 

[zixxerboy]

I always pull the carbs from the intakes. yes old rubber is harder and slipping them back on is a chore. whatcha goona do...

 

[krukster86]

Maybe this is just me freaking out, but I am starting to think that maybe I just need to get a set of carburetors that are actually designed for my bike vs the CB450 on the 360 that have questionable jetting. One thing that I have been seeing a lot is the Mikuni CB360 Carb set, complete with throttle, throttle cable, carbs, and pod filters. It runs a bit pricey but it looks real nice. Anyone have experience with these/opinions?

http://www.sportingforless.com/Mikuni-V ... -p/c04.htm

 

[sharperdill]

Did you end up getting this carb set?

 

[krukster86]

Nope. I ended up getting my CB450 carbs tuned semi-professionally and they are running really well. I managed to find a parts bike with excellent condition CB360 carbs so if anything I will experiment to see how the bike runs with stock carbs. I hear that the set I mentioned above in the link always claims to be "tuned for a CB360, no need for jetting" but it always ends up that you need to put a lot of work to get them right.

 

[crazypj]

I found a formula for car carbs last night.
Converting to cubic inch, CB360 needs about 38cfm per cyl at 11,000 rpm.
Anyone know max flow of 32mm Mikuni? (80~90 CFM?)
A single 32mm may work well on 360
Thinking about it, Kawasaki 900~1000 drag bikes only used 28~30mm, and that has individual cylinder bigger than 360
(901/4= 225.25cc per cyl, 356/2 = 178cc)
With CV carbs you can get away with too large venturi, it's still driveable.

PJ