HELLP = Choke problems... !

[georgesgiralt]

Have you checked that the idle screws are in order ? The tip is very fragile.
Have you ascertained that the tiny passageways  for idle are free ?
Have you checked that the butterfly are set properly ?
If your carbs are clean and the brass is in order, the bike will start at once with the basic settings.
Of course she lay not run perfectly because the engine is not new and the gas today is not the same as it was 30 years ago, but it is a good baseline.


Last but not least, the P/N of the carbs are stamped on  them, vertically near the top cover.

[Barry]

The carb type number is on the web  between the main venturi and the and the diaphragm housing.

[guyom]

Hi Guys thanks Barry (again) i found the number... 64/32/325-and 326... so 3/4 turns for baseline and i will tune up with this. I also change the fuel hose. I will try the bike soon.

[guyom]

Hi Georges thanks for help. Yes i checked the idle screws (clean and spring ok), the hole connected to the enricher discs, etc... that's strange... I found the number of the carbs : just 3/4 turns... but if the enrichers are not related to the cab tune up... that does change any things about the choke... i need to make new tests on road. Thanks for time.

By the way, another question : my silencer exhaust are shorter than stock ones (17" compare to 25" i think) i know that the total length of the exhaust can influence the tune up of the carbs.

--> Is that right ?

--> If yes, to your opinion, should i find the correct air/fuel ratio up or down the 3/4 turns ?

Thanks !

[Barry]

By the way, another question : my silencer exhaust are shorter than stock ones (17" compare to 25" i think) i know that the total length of the exhaust can influence the tune up of the carbs.

--> Is that right ?

--> If yes, to your opinion, should i find the correct air/fuel ratio up or down the 3/4 turns ?

Using different silencers may well result in a weaker mixture due to a reduction in back pressure and reflected pulses so it's something to check at high revs/load but it's not likely to have much impact on the idle mixture settings.

[guyom]

oK thanks I have a Carbtune to try to adjust the carbs as good as possible. I will try !
Guyom

[montmil]

Although the enricheners are installed correctly and mechanically functional, that bit of fuel from those mini carburetors has to get into the Bing's throat. If that's not happening, it might be time for a thorough cleaning of all the fuel passages within the carb bodies.

[guyom]

Hi guys l'm a bit confusing... I reset my carb, but clearly when chokes on, motor starts caughing and stops. RPM inscreases a bit at the beggining of the choke and after the motor stops.  When the choke is full on, no way to start the motor without a bit of gaz, otherwise, it stops !
I also saw another problem : to have the same RPM level at baseline when the motor is hot, sometime it's low, around 800-1000', and the next stop, at neutal position, it,s 2000 RPM. I put the fist gear and then the RPM decreases at normal 800-1000). Is it possible that my clutch is not correct ?

[Barry]

To be blunt the enricher on a Bing Carb is a relatively crude device and some work better than others. If you need to use full enrichment to start the engine you should reduce the amount of enrichment immediately. There is no way the engine will run on full enrichment except perhaps in the middle of winter. Also you can't necessarily expect the engine to idle with the enricher on or with it off until the engine has warmed up. Basically use the minimum enrichment needed and turn it off as soon as the engine runs without it but don't expect the engine to idle until you have ridden a few miles.

The high revs problem. Are you saying it's 2000 RPM in neutral and 1000 RPM with the clutch pulled in ?  If so that may well indicate the clutch is dragging and needs adjustment.  

[guyom]

ok so mine does not work well. but as you said perhaps in the middle of Winter, in Quebec, we have good winter ;-)

For the RPM problem : another road test looks better than the first one... at neutral, RPM looks more stable (around 1000) but something, they were high 2000 and to decrease them, i put the first gear, then release the clutch a bit and the RPM decrease to 1000. Then i put the neutral and that's ok (1000). So the clutch ?

[guyom]

Again : other remark on my tuning : when i accelerate, middle RPM are low and then increase... I joint a draw ;-). Do you have any idea why ?