Bonneville America Forums Forums Technical Forums General Tech Choke not working

Hi,

So, literally overnight, the choke on my '05 does nothing to raise RPM when starting. In fact, ambient temp is warm enough that it will idle rough with the choke in (or out) but will run better with the choke in (off). It will rev with throttle, and after a few minutes, I can drive off and she will run pretty well. Once warmed up, it runs pretty much normal. If I pull the choke out while cruising along, she will bog down. I don't know if that's normal - I've never had cause to pull out the choke while riding once warmed up, however, I've never really noticed the bike start to run rough if I forget to put the choke in.

I know these chokes are not really chokes, but enrichment mechanisms, so I'm thinking that either a passage is blocked, or something is preventing the choke from doing it's "enriching." It certainly seems like a fuel starvation issue, but does not appear to be either the pilot or main jet, unless the pilot jet is part of the choke mechanism.

Any thoughts on this?

Thanks for any advice!

Hidden filter becoming plugged?

You mean air? Removed it, no change.

No, Ryk means a tiny inline fuel filter located just before the carbs. Most people pull them just to eliminate another variable in the troubleshooting equation... that, and the fact that the petcock has a perfectly effective fuel filter anyway.

oh oh

Ok, I'll try that. If that filter is between the petcock and the carbs, wouldn't that affect the entire RPM range, especially higher, due to faster demand rate?

I have a tech manual, and it has zero info about the choke and what it consists of - not even an exploded diagram. Can anyone describe the choke - like does it have it's own passage for fuel?

Thanks for the suggestions!

A fuel filter will manifest itself more at higher RPM's .. (more fuel demand/less flow= starvation issues) sounds like an internal carb issue to me.

I'd be tempted to run some Seafoam or StarTron thru the system and see if an additive gives you a quick fix.

I've been running a dose of Lucas UCL, about 50 miles so far, no change. Going to try Redline SI-1 next. Sure seems like however the choke mechanism delivers a charge of fuel is being inhibited. I would think it has to flow through some passage separate from the jets, but I haven't tore into them yet to see what that would be. Or maybe there is a linkage that is broken so that pulling the choke doesn't move whatever allows the fuel to move. Another thing - it's "finicky" -- moving it in a little or wiggling it affects RPM slightly or will shut it down completely from a rough idle. Weird.

Your linkage definitely deserves a good inspect, before you tear your carbs apart. I would think just removing the fuel tank and a good light with an inspection mirror would yay or nay your linkage's functionality.

The "choke" mechanism doesn't actually choke anything. It works via a mixture enrichment system. When the mechanism is engaged it allows the engine to draw additional fuel into the combustion chamber.
Not sure "snake oil" will fix your problem.. sounds like a restricted vacuum passage.. I would look carefully at your choke linkage though.

Quick look indicates that the linkage is fine. I found an exploded diagram that shows the linkage operates a plunger that opens or closes the enrichment passage. Soon as I can get some time, I'll remove those plungers and see if I learn anything.