carb woes

[workerbee]

Hello all, I'm not an XS owner (although I used to own a 78 XS750, gave it to a buddy who rode it from Alaska to Oregon... www.neon-buddha.net for that story,) I'm currently making a little money working at a bike shop that specializes in 70’s – 80’s bikes and am having some “issues” with a 78 model XS1100E. It originally came in with charging problems, easily fixed but now it’s back with carburetor troubles. When started it likes to idle up to about 3 grand, if I pull the choke and push it back in quickly it’ll settle down around 1 grand but when you rev it up it stays at 3 grand and slowly comes back to idle. Runs rich as hell. It fouls plugs about as quickly as I can put them in. I’ve had the carbs off several times for cleaning, it’s been synced and there are no intake leaks. I replaced 2 slides that showed cracking in the diaphragms and lowered all the needles one notch to try and alleviated the richness – no joy. It’s got 137.5 mains and the pilots have no numbers, but after research (on this site) should be 45’s. We’ve ordered new 42.5 and 45 pilots and will put them in next week. I need to get this beast out of the shop so it’s owner can ride it, (he’s thinking of selling it after all the troubles he’s had,) Any help would be appreciated. Thanks guys.

[TopCatGr58]

Hey there Workerbee,

Well, as you have found from your research, the carbs have a lot of issues, when they are NOT working right!
Okay, checklist:
1.) ordered "NEW" pilots, hopefully Mikuni, not K&L!!
2.) is Float height set right!
3.) are carb bowl vent tubes free breathing, not plugged up, or not connected to vented chamber....check airbox to ensure they aren't clogged!
4.) Are the pilot screws set to about 1-1/4 turns out from gentle seat?
5.) Are the pilot screws INTACT, the tips like to break off, and clogg the circuit?
6.) IIRC, there is a rubber plug that goes over the end of the pilot jet on the underside of the carb, at least on some models, so are they in place vs. missing? They prevent the pilot circuit from sucking fuel straight from the bowl, instead of thru the main jet branch circuit!
7.) IT sounds like it will need to be resynched, roaming idle is symptom of that, but have to get previous items straight first!

FINALLY, how about telling the OWNER about this web site! I'm glad that you work for a shop that specializes in the CLASSIC bikes, we need more shops like that, but he might be willing to learn how to work on it himself once he finds THIS SUPPORT GROUP!? Not trying to take away your business, lots of folks don't necessarily like to work on their machines! Good luck with the carbs!

[workerbee]

Should get the jets in this week, hope that'll fix it, didn't think about the airbox though - I'll check that tomorrow. I appreciate the help and I'll keep y'all posted. I'll also send the owner here.

Safe riding

[skids]

There are many out there that either do not want to work on their bikes or are just too intimidated by it. It is refreshing to know that there are mechanics for hire that do a little research to get the work done right! My hat is off for those that are willing to take on these old bikes.

Originally posted by workerbee
Should get the jets in this week, hope that'll fix it, didn't think about the airbox though - I'll check that tomorrow. I appreciate the help and I'll keep y'all posted. I'll also send the owner here.

Safe riding

[MAXIMAN]

Workerbee,

Wherya at? I'm in Stillwater. There's a guy in Broken Arrow...Turbo's Bike repair. The Yammy shop wouldn't touch mine with a 10 foot pole. They sent me to Turbo. He's real good and works on lots of old bikes.

He will usually spend a few minutes on the phone with ya giving help when he's not swamped.

Cg

[workerbee]

We're out of Nicoma Park - (OKC/MWC) R&R Cycles, I just turn wrenches :-) no management worries. We should be in the book. Let me know if you get down this way.

Cheers!

P.S.

No jets yet.

[workerbee]

we dug some #45 jets out of a set of parts carbs, (who knows what the old ones were, they had no numbers,) stuck 'em in and it looks as if they did the trick. Carbs re-balanced and onto adjusting the air/fuel ratio and re-rebalancing. Yea! I hope I get to test ride it.

[Dennyz]

If the jet where unmarked, they could have been the K&L stuff that is know to cause problems.