Bought V&H full exhaust, pre-jetted carb bodies, and a K&N lunchbox to go with them from the For Sale forum here, brought them home, and finally got everything slapped onto my bike yesterday. The bike fires up fine with about 1/4 to 1/2 choke and warms up quickly, however, it will stumble and die after any throttle input. If I ease the choke back on after it's warmed up, the engine revs as I feed it more choke, which seems strange to me since the motor dies when I apply the throttle. Just going by smell and the smoky exhaust, I'm guessing it's running rich, but the revving when I apply the choke is throwing me for a loop.
Just wanted to run through the checklist of stuff I've gathered that I should look for this afternoon from reading the gajillion other threads on the subject:
1) Check for vacuum leaks
2) Air mix screws
3) Float height (pretty sure this is set OK, but I'll double-check)
4) ?
I've already checked the choke and throttle cables and slides, and they're routed properly and moving freely. What else do I need to look for, and in what order?
Thanks
We've have had floats in some people's carbs open when its being tossed about by the UPS guy and it stays open when you fit it on the bike ... then you take it off and miracle of miracles its fine ... all the shaking taking it off fixes it ... :x ... worse than a problem you cant figure out is a fix you cant figure. That be my first guess ... OK you got overflowing fuel ??? if not OK not that problem ... BTW people say the carbs were clean and they swear up and down ... and turns out (in my XS 650's case) he cleaned them 3 years ago and never rode it after ... and he now cannot believe its gummed up ... welll duh ... I rode my bike 2-3 days minimum every week and never cleaned the carbs in 5 years ... and its never been a problem ... Not fair ... booo hoooo :? ... but its perfectly normal.
Cool.
Srinath.
pulled the carbs back off, took them apart, measured float height per the clymer's manual etc. etc. Sprayed the jets down with some carb cleaner, they're all clean, slides move fine, etc.
I put the carbs back on, checked for vacuum leaks, hooked up a fuel line and kicked it over - same problem. Bike runs on half- to quarter-choke for a bit, then no choke after about 30 seconds. If I feather the throttle up, as soon as it gets to just over 2 grand it stumbles and dies.
The previous set of carbs, which were gummed all to hell, work fine other than showing the signs of being gummy - delayed throttle response, etc. The problems there are that they aren't jetted for a lunchbox and an aftermarket exhaust (they're Cali carbs so they're already lean as is) and whatever mechanic the previous owner took the bike to did a carb cleaning 3 years ago and in the process stripped the screws on the right float bowl and I can't get the damned things out no matter how hard I try -- meaning, I can't get to them to clean them well.
I'm about ready to suck it up and take it to a stealership to let them get the damned thing running, I'm tired of banging my head against the wall.
send me your spare carbs ... I'll get it jetted for K&N and V&H for $40. Yea add shipping and make a note of what you want me to do on it.
Cool.
Srinath.
round three, m'f'ers --
Sleeping on it for the night made me realize I really don't want to dump another couple of hundred bucks into the bike and wait for weeks before I get it back from the shop, so I decided to give it one more go.
I pulled apart both sets of carbs as best I could, and took notes. Here's what I found:
Jetted carbs (the ones I'm trying to use):
37.5 pilots (factory) and 134 mains - I'll swap these to your recommended sizes once I actually get the bike running :x
The o-rings from under the vacuum fittings at the top of the carbs (the little ones that are up by the slide diaphragms) were missing -- replaced.
The needles were resting on top of the spring seat instead of underneath it. Fixed that.
Lastly, the needles from each set of carbs looked different. Here's a picture. On the left is a needle from the carbs I'm trying to use, and on the right is a needle from the stock carbs. The needle on the left is about 1mm longer, tapered, has notches for adjusting the placement of the clip at the top, and has/had no plastic donuts. Should I stick with these needles, or swap the ones over from the stock carbs and shim them up with some #4 washers as in the FAQ?
(http://count-funkula.com/needles.jpg)
That 150 and washer etc is all for stock needle. You have DJ in it. You on your own there ... someone has to have one of these working ... try posting asking for help ... with DJ crabs ...
Cool.
Srinath.
I *think* I have it running now, but won't know for sure until I take it out for a ride. I'll report back later this evening or tomorrow with the results -- I haven't put the bike back together yet and I have a project due and a test tomorrow.
Thanks for pointing out that those were DJ needles, Srinath -- I downloaded their manual and worked from there. Right now I'm set with the circlip at the last (topmost) notch in the needle (DJ recommends starting at the 2nd notch), shimmed underneath that with the plastic donuts from the factory carbs, 2.5 turns out on the idle mix screws (DJ recommends starting at 2 turns out).
DJ crabs indeed :x