[mag]

imported post

I'm still having flooding issues with #1 carb, it seems. However, all the plugs read white now. The bike starts with choke, but seems to not catch easily. I have to start a couple of times, then shut off choke once running, then throttle it and leave the throttle lock at 2000 rpm for a couple of minutes. It idles fine, no smoke, though sometimes the idle drops erratically. There is a constant drop of gas on the float bowl drain screw. I couldn't get the float in #1 to pivot totally free. I changed the pivot pin, float, etc. It seems there might be a casting problem with the pinion, ie alignment, so that it causes a 'wow' in the pin or something. It slides in easily, then at the last 1/3rd of the pin length i have to tap it into place. I don't want to break the aluminum pinions by trial/error tapping on the float pin to 'straighten' it? Also, worried about over-sizing the float pin mount holes in the pinions by burnishing them or reaming with a dremel. Suggestions? I'm only getting 28-35 mpg now. Maybe i set the float too high in an effort to seat the float valve? Before i was having fuel leaks, but at least 40mpg.

 

[mag]

imported post

Thanks, Paul. As i said, i have replaced the float pin twice. The current one rolls flat, i checked before. I only have to throttle open at initial startup, a couple of pulls, then it idles fine. The bike accelerates great, and apart from a little choke/throttle at startup, it runs great. But my mileage really sucks now. All other tuneup issues are resolved.

 

[mag]

imported post

If my float level was too high, why wouldn't the plug read black, ie, running rich. With the plugs almost all white, could the bike be running lean, ie not enough fuel delivery in carb 1, and causing higher fuel consumption overall?

 

[mag]

imported post

So if my mileage has gone down, and it seems like it's not getting enough fuel at startup, would this still suggest a flooding problem? I assume this is why my float bowl screw is seeping gas, though maybe it is just worn.

 

[mag]

imported post

definitely too high, and definitely binding on the float pivot pin, since i've replaced all the other parts, including swapping out floats/pins/valves. But the pin rolls flat on a table!

 

[mag]

imported post

Thanks, Marco. Both the pin and the float pin hole are clear and smooth. The problem actually seems to be with the carb casting. The pin slides in smoothly, and when it reaches the last 1/4 of the way, i have to tap it in. I think it causes a 'wow' in the pivot pin at this point?

 

[mag]

imported post

ok. I realize now i was adjusting the float from the valve tang, and not the float arm tang. I had assumed it was the smaller pin valve tang since this is what makes contact with the valve assembly. Wrong, i guess. THis is possibly why the valve isn't seating? off-angle, not plumb float action.

 

[mag]

imported post

#1 is the only one leaking out the float bowl drain screw, and the only one i adjusted, from memory.

 

[mag]

imported post

i took off the carbs, put the OEM fuel screen on the #1 float valve that i had from my other carb set, and adjusted the float to 21mm with the float arm tang. This seems to have stopped the leakage/flooding. The bike idles perfect now. Still needs a little choking at startup, but warms up quick. Not sure on the mileage thing, will report back. The bike seems to accelerate smoother at low rpm now. I still noticed 'hiccuping' from the carbs at startup, though. I think maybe my vacuum pistons are hanging up (i was in a rush to ride, so didn't take off the carb tops -- doh!).

 

[mag]

imported post

Hey Guys -- just went out for a ride, topped up and checked the mileage -- 41mpg city!! Not a drop of gas leaking anywhere, the bike idles perfect and runs smooth as silk.

Still a little choppy at first startup of the day, though i wonder if that is because i am starting it right after turning the petcock on. I would think there's enough gas in the float bowls. Once it catches, it holds idle without choke, but it sputters for a little while with choke on full at first. If i take it off choke briefly, crack the throttle a couple of times, then re-choke for 30 seconds, it holds fine.

Anyway, the bike runs like a hot damn now!!!!

 

[mag]

imported post

Ok, so float drain screw was still leaking, and over the course of 1/2 a tank, mileage dropped. Also, backfiring. So, off came the carbs, again. I decided to have a closer inspection of the air-cut valve, and discovered i had installed it upsidedown /forums/images/emoticons/shock.gif So, i put it in properly, pin side up, and proceeded to readjust all the float heights in the carbs. Turns out some of the float heights were out a few mm, when measured on the inside set of the floats. Back together, whammo, runs great. So far, fuel consumption looks excellent. No backfiring, no leak so far. Crossing fingers.

 

[mag]

imported post

Thanks, Exavid. I wish it was the case. Just checked the mileage, and got only 31 mpg. I've adjusted the pilot screws to lean it out a bit. The #1 float drain screw still leaks, which is odd, because it was at rest overnight with petcock off. Makes me think it's not from overfilled bowl, but just an old o-ring. Anyway, no smoking, decent acceleration, great idle, but still low mpg. Kinda stymied. Maybe leaning out the pilots will affect mpg next tankful. Can't see how.

 

[mag]

imported post

I had assumed that the carb drain screw is leaking because of an overfilled bowl. On these bikes, there are no overflow tubes. The plugs read normal now that the aircut valve is in properly, i actually get a little gradation on the plugs rather than bone white. As i said, it's certainly not smoking, the plugs aren't fouled, the timing is spot-on, it idles and accelerates fine. I'll check brake drag, and will also put a new carb drain screw o-ring on. Perhaps pilot screw adjustment will make a diff, though it wouldn't seem so after 3000rpm. It has a newer K&N air filter, which i can see through still. Maybe i should try the stock paper one. Also, could a clogged gas cap vent cause rich running? I don't even know where the vent is in the cap.