Came for C70, left with Aero..with busted "fuel mixing tube"

[caddyss]

Great forum guys...I bought a complete 1970 C70 to help with my 1962 C102 rebuild, and for a few bucks more, the guy threw in an 85 Aero 50 NB50 M. Awesome for me, not so much for the wife. Aero runs like a champ once its running...but to start it you have to put mix into the spark plug hole. Will keep starting right up for a few hours after that but the next morning same thing. Upon carb reassembly after a thorough cleaning, I noticed the tube off to the side that would be under the by starter broken off. The two brass tubes/towers in the middle are fine. The Wikispreedia article on "what's a by starter?" calls it a "fuel mixing tube". I researched it on the forum, and noticed a couple of you had the same problem, but strangely your symptoms were different.

Would the broken tube cause this type of trouble? If the bystarter is retracted when the bike is cold, why would the broken tube cause it not to start (assumingly gas is still trickling down)? The bystarter was tested and seems fine.

Also, if this is the problem, where (if anywhere) can I find just this tube to buy? Can I "pop" one out of another carb? The scooter runs great otherwise except for a pretty stiff lurch into second gear (which I'll save for another post ), and I don't really want to get a whole new carb if I can help it. I'm driving to Key West in a couple days (scooter capital of Florida) and thought I could find one in a shop/yard down there maybe.

Thanks everybody, I have no experience with scooters this "new".
Dave

[caddyss]

No takers on this?

[Wheelman-111]

Greetings:

I think it's because nobody's too sure what you mean by "fuel mixing tube". The main jet holder is a cast tower with threads for the jet that holds down the emulsion tube. The Pilot jet feeds mixture through a brass standpipe that's simply pressed into the carb body. The standpipe can be removed with care by slipping a drill bit into the pipe that is JUST barely small enough to fit. Then a Vise-Grip can be employed - without crushing the pipe - to wiggle-tug-wiggle-tug the tube out. Once removed, if the wiggle didn't enlarge the bore in the carb body too much, a replacement can be pressed back in the same way. However if the previous owner didn't know enough to put it back, or Couldn't for reasons mentioned, there's no telling what crazy mixture that engine is inhaling whether the bystarter system works or not. Plus the tube may not be the only thing wrong.

It's possible someone can send you a replacement standpipe, but far more likely someone has removed a PA carb from an Aero or Elite to replace it with a bigger aftermarket Polini or OKO. That take-off carb, presumably in good working condition, typically sells for $35 give or take a few dollars. That, along with consideration of the Aftermarket yourself, is almost certainly the better option.

[caddyss]

Hmmm...sorry. I got the term "fuel mixing tube" from the Wikispreedia article on "what is a by starter". The guy who wrote the article called it that and has a blue arrow pointing to it. It is the tube that would be directly under the by starter needle when the carb is assembled. It is the "3rd" pipe or tube off to the side of the carb. Also, I searched on here, and a few other people referred to it by that name as well. Mine is busted off, and am curious if this is causing those symptoms.

Thanks again

[Wheelman-111]

Greetings:

Mr. Mousewheels has probably forgotten more about Spree carbs and electronics than the Forum Collective has ever known. Unfortunately he doesn't come on the Forum any more. We miss him. This was mostly his doing: http://hondaspree.net/wiki/index.php5?t ... at_It_Does
One can only imagine what happens to a carb mixture when all this marvelous engineering is rudely busted off. Used Honda bystarter replacements are generally considered superior to brand-new cheap cloned stuff from Asia. Find a good used one.

[caddyss]

Thank you wheelman,
The bystarter itself is new...I'm curious if just the brass tube in the picture itself (which is not part of the bystarter) can be purchased or found somehow.

[caddyss]

I'd like to thank Bones for his very gracious offer to help me while I was in the Keys. Thanks for the know-how, the parts, and the hospitality. And it was a pleasure hanging out with you too...look forward to seeing you again next year. I'll give the parts a whirl when the temps up here get over 30 degrees.

[bonesv]

'twas a pleasure man and I hope you do get that fixed. I really enjoyed meeting you and the fam-awesome dinner and thanks for the shout back! I'm getting the new carpet installed on the Capt's boat and my fishing reels will be ready bro!!!

[motormike]

Just in case you get stumped again with the repair, I have a spare 85 Aero 50 parts bike complete with carburetor.
Get back to me if you decide that a replacement is in order...

[caddyss]

Thanks motormike...will do. Right now the only thing that the bike does not have is the hardware holding the plastic panels on. I'll take a closer look soon.

[caddyss]

Update: after putting in Bones' fuel mixture tube (looks just like a jet), the Aero seems to be doing great. I popped out the broken off piece, slid in the new tube and even after a couple days sitting without running, it started right up. Thanks again! One thing that did surprise me while testing it out was how crappy the bike runs without the air filter cover on. I couldn't figure out why it was bogging down so much at mid and full throttle...put the cover back on and runs fine. This doesn't occur so drastically with my other bikes.

[motormike]

Update: the Aero seems to be doing great.
even after a couple days sitting without running, it started right up.

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