funky PO re-jet

[pete_s]

I agree to recommend to buy Mikuni jets only, I wasted time with pilot jets from www.jackssmallengines.com
and they looked perfect and new but were twice the bore size of stock for the same numerical number.
#45 mikuni was about .012 inch
#45 Jacks was about .025 and the bike would not run at all!

[Espiritus]

Stuck tip

Been there, done that

OK, Boots, I have been exactly where you are now, right down to the irritation with crotch-rocket bikes flying by as I diddled with that wretched carb with the broken tip. Then there was TopCat telling me that I HAD to get it OUT. . .

Cussing and drinking didn't help.

Anyway, I tried just about everything. What finally worked for me was using a blow dryer set on high and very small pieces of ice, and a set of dental size tools with cushioned handles that I bought from Home Depot for $4.99. Walmart has them as well. I set the blow dryer to blow INSIDE the throat of the carb while putting tiny pieces of ice in the tower to try to keep the brass tip colder than the aluminum. I got it very hot on the inside and then pushed the tip out with the right angle tool.

I've been told that aluminum heats quicker than brass. I did try dipping just the carb that had the tip into boiling water (with some dishsoap in it) to see if that would work. I have the absolutely CLEANEST carbs in the whole world, but after the "bath" I still had that tip in it.

I had already enlarged the hole around it in my frustration to get it out. It had been gouged by the PO, which led me to greater frustration when I realized that he had mislead me about the condition of the carbs even worse than I had expected.
The JB Weld that I used to repair the enlargement has been in for almost two weeks and is holding. It is something that I will have to check on every so often to make sure that it continues to hold but the carb is firing and idling.

It really will come out. . . eventually.



Cam

[jimmy boots]

throttled body

okay, so i huffed, and puffed, and then i DRILLED that b**ch out with a #60 bit cuz i couldn't stand it anymore. wuz holdin up my project. the hole is tiny but definitely larger than normal, two of my other carbs seem to have been given the same tlc by a po. half a millimeter seems difficult to adjust with JB weld, tho i did just do a bang-up job on my float post with the stuff:



as far as the pilot screw holes go, can I try to use them as is? also a bit of chafe inside the throat of carb, is this going to have negative effects?


thoughts?

[bikerphil]

broken off tips

The set of carbs on my Special had broken off tips in 3 of the 4 carbs when I bought it. One tip I got out easily, but the other two I had to eventually drill out. I bought new idle screws, but what I had to do was shorten the spring on the screws that keep them from turning so they would go down into the carb body further. Now the sharp tips of those screws stick down in the carb throat much more than normal. I did manage to get the mixtures set correctly, but it wasn't easy. The adjustment was very, very sensitive, but she idles very good at 900 RPM and the transition between idle and main circuits are silk smooth. So what it's worth, the carbs CAN be tuned without patching the needle holes, but it will be a lot more difficult. Good luck!

[jimmy boots]

what's the deal with airline food?

Hey all,

Finally put the carbs on, but I am having trouble tracing the cause of crappy idle. Cyls 3 & 4 are gas fouling and the pipes, while warm, don't sizzle when wet like 1 & 2. Oh, and a bit of white smoke out of the right tailpipe.
It idled, needle steady at 1k for a few minutes but didn't sound smooth, eventually died and didn't want to start back up.
Carbs are clean, stock jetted, twist-tie pre-synched, floats all meter fuel evenly on the bench. Spark plugs are new bp6es, sparks all nice and purple. Petcocks are clean, all settings work as intended. Idle screws all 1 1/4 turns out.
The only difference I can think of is that the idle screw holes are drilled out a tiny bit bigger (on carbs 1 & 2!). So they might be getting a leaner mix, and maybe I have the main idle speed knob opened too much to compensate, and that in turn is sending too rich a mix into 3 & 4 cyls?
If that makes no sense, I am open to more learned advice. Play with the idle screws or look elsewhere?

some wisdom por favor

[skids]

The pilots are not air screws, they are fuel screws. Bigger holes can mean richer mixtures. I drilled out a couple also. I had them adjusted pretty good, but going down long grades with the throttle shut down would vacuum fuel through the enlarged holes. They would pop in the pipes. Otherwise they were fine.

[jimmy boots]

ya know, i never worked out exactly how the pilot screws function, seems like a hole that goes nowhere since the other end is threaded in. are there other holes inside the idle screw tower that lead down to the float bowl?

anyhoo, how can i get those two cylinders unflooded?