Thanks! Yeah each carb was disassembled and cleaned even though they looked good. I agree about the boots; 30 bucks is worth eliminating the possibility of that being an issue.

 

Might also be worth running a bit of Seafoam through the gas. Does a nice job cleaning out gunk that might be clogging stuff.

Nice find if you can get it running cheap. I needed a parts bike recently (mostly for a frame) and didn't look around on here at pricing first. I ended up paying waaaay to much for a POS that barely gets above 60mph because I rode it around town and it seemed to run OK then. All I wanted was the frame and title but it would have been nice to have paid three or four hundred rather than the nine that I did pay. Live and learn, I guess.

 

The kid I bought it from said he had just put some in, but as clean as things were when I found it I am going to try regular gas first once I get it together.


Did you at least get some good parts from it for what you spent?


My carb boots arrived yesterday but I didn't have time to work on it.

 

After rebuilding some 20 sets of CBR carbs and many from other bikes, I'm not a big advocate of Sea Foam.


It may work on a bike that sat for a month and is running rough, but most of the pilot circuits I have seen are plugged pretty good. Some I had to throw the pilot jets away and buy new because they wouldn't clear even with boiling and ultrasonics.


The CBR carbs in particular are quite finicky. They have to be spotless in order to run properly. Sea Foam won't do that. It's a "quick fix" in my experience and not a very good one. I know there are people that swear by the stuff, I'm just not one of them.

 

+1 on what Dennis said about seafoam. I've tried it as a test and it didn't help at all. My carbs looked pretty much the same before/after.
I had an even worse experience when I used it in my weed eater. Put it in exactly to the directions. The weed eater started up fine, ran for about 30 seconds then seized up tigher than a drum. I guess in retrospect, it was a good thing as I hated that thing and wanted a new one anyway.

 

I guess we all have our own experiences but I have the exact opposite of yours, Dennis.

First of all, I seriously doubt that Seafoam could cause a weed-eater to seize up. Physically impossible. It is a cleaner mixed with a light oil and all it does it lubricate and dissolve. However, since correlation is not causation I suspect that it was about to freeze anyway and just happened to when you ran the cleaner.

On the carbs, I have been a Harley mechanic for about twenty years. (Caveat: the HD carbs are the exact same carbs but without the air pilot since they don't have to be balanced as it is a single carb setup. Maybe that makes a difference on chemical cleaners versus disassembly. More on that later.) However, if a bike has been sitting for a few months (Harley's never run rough after just a month of sitting but often do after six or more months) I drain the gas, flush the carb, refill with fresh gas and about an ounce of Seafoam. This works about 3/4 of the time, gets the bike running decently and then just being run regularly with fresh gas will usually clean out any residual gunk. If it doesn't take care of the problem or if the bike has been sitting for years I disassemble and rebuild right off the bat. (Got a "three years since..." project coming in this weekend)

As far as it not being a particularly good quick fix I disagree. I can put .50 worth of cleaner in and see what happens. If it doesn't work, I am out .50 and I rebuild the carb. As I said above, probably works 3/4 of the time in my fairly extensive experience.

Now, getting back to my caveat, I know a lot less about multi-carb setups. Maybe that pilot circuit is so fine that they clog up really easily and the Seafoam just never gets in there. For many applications, including EFI however, my experience has been pretty positive.

 

Got the title I needed. Was going to use the carbs but after the running issues with the parts bike I sent my original bank in to Wired George instead. Hopefully I'll get most of my $$ back when I get rid of the parts bike (sans frame) and then at least it will just be a learning experience rather than an expensive learning experience.

:-)

 

Comparing apples to oranges here. Harley engines are large capacity with single carbs.


A Honda 600cc is half the size or smaller than most Harley's. The CBR has 4 carbs...one for each cylinder. Essentially it is four 150cc engines with its own carb. The fuel circuits inside the carbs are very small. The pilot circuit is essential in starting and running. They generally won't start with a dirty pilot circuit. The pilot jets are approximately .030" These carbs are also very different from a Harley carb. I've rebuilt Harley carbs and they are nothing like a CBR carb other than the basic design. CBR carbs are very finicky to get tuned properly. Harley's will run with dirty carbs...maybe then if you can keep them running the Sea Foam has a chance to do something...not unlike just getting gas to move thru a dirty carb. Problem is most CBR's if they sit there is no way you will get anything to flow thru them.


You might have success on Harley's but I've never gotten Sea Foam to do anything on a CBR with dirty carbs...or any of my other bikes which run the gambit from 50cc's to 1200.

 

That was sort of my point. There were a couple blanket condemnations of Seafoam but really the issue is a specific type of design for which it isn't effective.

I agree with you totally on the CBR carbs. Given that they are both (Harley and Honda) Keihin CV carbs I figured I could easily rebuild my own bank with twenty years of experience. Tore them apart, was really careful to keep track of what went where, how many turns various screws were set at, etc. Did that four times before I finally sent them to Wired George. Gah!

Maybe I'll take the bank off the parts bike (which runs albeit poorly) and do a rebuild for practice with no pressure since it's going to be parted out anyway. See if it runs better before I tear it apart and get rid of all the bits. Can't hurt.

 

I would say it's more like you found "one" specific type that it works on. Some of the time.


It is not just CBR carbs...pretty much any bike I have worked on with multiple carbs. That includes metric V-Twins BTW. Also anything with a small engine. From my perspective since I rarely work on Harley's, that is pretty much everything.


My perspective is if it needs cleaning take it apart and clean it. Sorry I can't give you a thumbs up for Seafoam.