Honda CB 550 Complete Carb Rebuild: UPDATE REDUX

Float Needle and Seat for the CB550

Back into the carbs I went…I think this makes it 4 or 5 times now.  I removed all the float bowls, and swapped out the main jets for the ones that had been in my old carbs.  They didn’t necessarily look any better to the naked eye, so maybe it’s superstitious, but they worked on the old carbs pretty well.  I also took out the slow (pilot) jets, put a VERY small copper wire through them, and sprayed them with aerosol carb cleaner, and lastly blew them out with the air compressor.  These things seem pretty sparkling now.  They better work!

I then double (or is it quadruple at this point???) checked the float levels.  They all seemed pretty tight to exactly 22mm, but I just wanted to make sure.  One thing I noticed, is that the float needles that I had cleaned up and reinstalled from this new rack of carbs, did not seem to allow the spring to flex under the weight of the float itself.  To determine the correct float height, it is imperative that you measure the distance between the lip of the bowl, with the top of the float itself.  You need to be sure that you are measuring when the tang of the float JUST hits the needle, not allowing the weight to depress it in any way.  If it does, your measurement will be off by only a few millimeters, but will cause you no end of headaches later.  I checked the needles in the old carbs, and although the measurements were the same, exactly at 22mm, the needle easily depressed in from the weight.  I decided to swap these out as well.  I made sure to spray some cleaner through the needle seat while I had them out of there.

Reassembled the carbs with the float bowls on them.  This time, made sure that the drain screws were all facing the correct direction, to make it easy to check float levels when I have them back on the bike.  Knowing that the last time I removed the carbs, would be the last with the easy pod removal, I wanted to make sure there would be very little chance I would need to do this again.  The air box to carb boots I bought arrived, and this time, the assembly would be with the full, stock air box on.  If you have never done this installation, trust me when I tell you, it’s a total pain in the ass.  Getting the carbs on, with the air box in the way, makes people scream, and I am one of those people!  But I held it together, long enough to get the carbs on, with a new trick of removing the battery and tray from its location behind the air box.  This allows you to line up the carbs on the manifolds, and then sneak the air box into place from the rear.  Much easier, and much less cursing going on.  After that, it’s easy to install the battery again in minutes…problem solved.  Something tells me that I will use this trick again…and again, and again…

Carbs rebuilt and ready to go on the bike...AGAIN!

The first test, after getting it all assembled, was to see if the gas would come pouring out again, from the overflow tubes on the bottom of the float bowls.  This is common, since the carbs have been turned every which way while off the bike, causing the floats to be hung up on the edge of the bowl when turned upright.  The quick fix to this, believe it or not, is to smack the bowls gently with a rubber mallet or hammer.  if that fails, take the bike off the stand, and rock it sideways several times, letting it dip about a foot towards the ground, in both directions (have some help on hand if you are uncomfortable with this, to make sure you don’t drop the bike).  This allows the gas to swish around in there and free up the jam.

I opened the petcock, and let the gas loose to the carbs.  No leak.  Nice!  Unfortunately, the large garage door is not working now at the shop, and with the other fellas working in here, I figured it best to avoid the carbon monoxide in the space.  The real test, firing it up, would have to wait until tomorrow.  Stay tuned, I have a good feeling about this…

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