fuel gayness

Hillchop · Full Member Joined: Sep 09, 2008 Posts: 108 Location: 604

hey fellas...seems i've run into a fuel problem? been riding my bike for the better part of the summer with more or less no troubles until recently...decided when building the bike i would run velocity stacks and now i have a feeling the bike is running like shite because of it? bike idles great but during acceleration tends to "slip" or "shudder"....the bike will accelerate but not without well, the best term seems to be, shuddering in doing so...carbs need a good disassembling and cleaning from running stacks? running straight pipes and didn't mess with needle sizes etc because it initially ran great... really pissing me off as we probably only have a few weeks of good riding out here before the torrential downpour hits....any advice would be greatly appreciated...thanks in advance

p.s searching similar troubles on the board as i type this Laughing

yamaman · Posted: September 1, 2009, 8:45 pm Post subject: Re: fuel gayness

What were you running before? Stock air box? Put it back that way & see if that fixes it.

You should need to go up a size or 2 with stacks as they will flow a lot more air than stock box.

Do the stacks have filters? I used to run stacks-no filters. I put K&N's on & ditched the stacks the first time I pulled the donk down.......Nasty stuff dust & dirt!

Hillchop · Full Member Joined: Sep 09, 2008 Posts: 108 Location: 604

thanks for the reply yamaman, before the stacks i was running open carbs...not smart i know, but i built the bike as a stripped down chop so unfortunately proper aircleaners weren't an option...never liked the look of the 'pods' either so it had to be velocity stacks...the bike has run awesome all summer except the last few rides so i'm hoping its just a build up of gunk in the system...i've got the carbs apart as we speak and they did have some gummy stuff here and there...the back of the main flapper dealy (on the engine side) had a healthy coating of black oily tarry looking business...a bad sign i'm sure...

also, anyone know the proper way to remove the float assembly on a bs34? off an 80 special....thanks in advance

joe

Hillchop · Full Member Joined: Sep 09, 2008 Posts: 108 Location: 604

so as of now i've rebuilt/cleaned the piss out of the carbs, re-set points, static timed it, swapped petcock, new fuel filter, new plugs, adjusted and readjusted air mixture....i'm at a loss....ran a bit stronger but still the misfiring / shuddering...seem to have a bit of a weep coming from the base of the jug on the right side but would that be enough to make it run like this? it ran awesome just weeks ago???? condenser maybe? checked voltage at battery while running and multimeter says 11-ish? anyone dealt with anything like this?

thanks in advance

joe

highspeedhamish · Full Member Joined: Jun 25, 2009 Posts: 62

Bad coil?

Retiredgentleman · Posted: September 2, 2009, 11:51 pm Post subject: Re: fuel gayness

Your engine will never run right if the voltage is low. 11 volts at idle is bad news. At idle battery voltage should be at least 13 volts. At 3000 RPM battery should be 14.1 to 14.5 volts.

Forget about your carb tuning, until you get your charging system sorted out.

As for your carbs, there's a tremendous amount of info available on this site. Look in the "Vault" under "Carbs". Go down through the "Fuel" forum past threads.

Hillchop · Full Member Joined: Sep 09, 2008 Posts: 108 Location: 604

i hadn't really suspected the electrical system as i've been keeping a close eye on it (or so i thought)...been checking the battery after every ride to see if theres been drain on it and so far its been minimal to non-existant...never checked it under load which i suppose would have been a good idea...in any case i've got some more reading to do...

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