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After I got the rectifier deal straightend out, it seems like one side doesn't give off as much exhaust. I am kinda thinking maybe one side is getting more gas because I know the carbs need to be cleaned because they run gas out the overflow tubes. Can somebody point me in the direction of where to get rebuild kits and a general idea of what it takes to do them. Sorry for yet another post about carbs, but thanks for the help.

Hold on there, Pilgrim! (*affects yet another lame impression of John Wayne *)

Are you sure you want to tackle this? Well, if you insist...

Naturally, any decent Honda dealer or bike repair shop can get you the carb kits, but if you want to save a few $ you can find lots of places online to compare prices.

A general overview might go something like this:

*If you have a camera, it is adviseable to take a shot of everything just before you remove it. That way, you can refer to the pics if you're not sure how it needs to go back during re-assembly.*

1) Remove throttle linkage and any fuel/vacuum lines from carbs.
2) Remove carburetors from engine.
3) Disassemble carbs: remove float bowls, jets, etc. Everything you can get off, take it off.
*Note: Take extra care with all brass parts and screws since they're kinda soft. Make sure your screwdrivers are in good condition and fit the slots well.
4) Scrape off the old paper gaskets (gently, don't gouge the carb mating surfaces).
5) Soak the carbs in Carb Dip overnight to clean out the passages. Spray carb-cleaner can be made to work, but dip is easier and does a better job.
6) Install the new parts, gaskets, etc. supplied in the kit.
7) Check and adjust the float levels. This is a critical step. The specs will be in the service manual. It may be necessary to do this before final reassembly of the carbs.
Reinstall the carbs, linkages and lines. Turn on the fuel and check for leaks.
9) No leaks? Fire it up!
10) Synchronize! You'll need a synchronizing tool for this.
11) Wait a sec... there is no step #11. Test run!!!

Questions? Just ask... we'll try to help.

I find my mechanical skills to be on par, is that perhaps not enough to tackle rebuilding a carb? How much would a professional charge?

Also, I am going to be running a Mac's 2 into 1 exhaust because the stock exhaust is shot, so what do I do about jetting?

Why am I getting a headache already?

2 Wheel Virgin wrote:I find my mechanical skills to be on par, is that perhaps not enough to tackle rebuilding a carb? How much would a professional charge?

Also, I am going to be running a Mac's 2 into 1 exhaust because the stock exhaust is shot, so what do I do about jetting?

Why am I getting a headache already?

That headache is a sign to stop sticking your head down by the exhaust for so long.

2 Wheel Virgin wrote:I find my mechanical skills to be on par, is that perhaps not enough to tackle rebuilding a carb? How much would a professional charge?

Also, I am going to be running a Mac's 2 into 1 exhaust because the stock exhaust is shot, so what do I do about jetting?

Why am I getting a headache already?

Sorry, I didn't mean to offend, honest. I have no way of knowing what your skills are, and I didn't want to mislead you into thinking this is a piece of cake. Hopefully it'll be easier for you than it is for me. What usually happens for me is I'll forget to install a certain part or somehow get it in upside-down and not discover my mistake until I'm ready to start the bike. Anyhoo...the main thing is the more methodical and painstaking you are, the better the final result.

I'd say $100 + parts per carb body would be a minimum charge you could expect to pay a skilled pro, if you take him the carbs.

I doubt the pipes will force a re-jet, but if you want to experiment you could order with the kits a couple extra jets in the next larger size (they should come with new jets in the stock size).

Hope you get 'er running well soon. A good long ride should help the headaches ease off some!

One more thing to look at, you said the exhaust is shot.... is the side with less pressure at the end possibly leaking pressure someplace else along it's length?

Like I have stated before a friend of mine just purchased a 78 CB400t as well with all the same problems as yours.

After finding the problem with the one cylinder running and fixing it. I yet found that the exhaust was only exiting from one side as well.

These bikes have a cross over pipe under the bike that goes from one to the other so exhaust is exiting from both sides just not out one of the mufflers.

After removing the clogged side (the right side) I found all of the baffling to be collapsed and blocking the entire exhaust. No big deal I was able to clear all the baffling out and made the exhaust free.

Removing the left side I found the muffler to be completely rotted out. No big deal I ordered a set of universal pipe out of bing.com $36.00 shipped should arrive here buy Friday.

I also found a carb rebuild kit off of eBay for a buy now price of $12.99 I ordered 4 kits since I have another bike a 81 CM400t that I need to get going. All 4 kits with shipping came to $62.00 and was at my front door in three days. Not Bad!

Wow! Glad to see a lot of people willing to share their knowledge. As for the possibility of the exhaust being clogged, it's not. Probably because it is in the dumpster becuase of how rotted it was. The guy I bought the bike from showed me the condition of the stuff and I just threw it away. He had been trying to weld it and it was a mess. So in the mean time he threw a 3' lenght of exhaust pipe on each side straight from the head pipe..... Now you can understand where my headache came from

That is why I am going to order a complete exhaust. Thansks again.

When you removed the mufflers did you remove the cross over pipe as well?

If not then there's your uneven exhaust.

But if you did remove it and if your running off of the header pipes then it sounds like lower compression in one cylinder.

I wouldn't panic about it to much. get an exhaust on it and run it for a day real good then check the compression in both cylinders if it's real close to each other don't worry.

On the two bike in my garage right now (78 400t & 81 CM 400t) with the exhaust off the left side seems to be giving out more exhaust.

Good Luck!!!

and post back!

Mike