Bonneville America Forums Forums Technical Forums General Tech Running rough

This is about my Daytona, but I'm asking here because there are several people w/ triples on here, and smart mechanics too. The bike's a 2000 Daytona 955 (fuel injected). When the outside temperature gets warm (over 80 F), this bike runs rough. It idles rough and just seems to be "missing." It's worse at steady throttle positions, and the bike still accellerates strong on warm days. It's bad enough that the bike's not fun to ride when it's warm, and it just sounds bad inside my helmet. When it's cooler outside, the bike runs much smoother across the entire throttle range.

Also, not sure if this is related, but when I get off the bike on a warm day, I have an exhaust stench on me that is worse than any I've ever smelled before. I don't smell that bad after riding on a cool day. Is it possible I've got an exhaust leak that gets worse when it's warm? And would this have anything to do with the rough running?

I've synced throttle bodies, replaced plugs and air filter, and didn't notice a difference. I'm going to take a look at the fuel filter when I get a chance to open up the tank.

Anybody have any ideas or suggestions?

Thanks,

Will

Not an expert, but it sounds like it is running rich. Maybe check connections on TPS and/or whatever else would control mixture.

Hey, Will, pop the air cleaner out, ride around the block and see what happens...that's likely to diagnose a rich/lean condition right away.

Ed,
I'll give that a try this weekend. On the Daytona, that's a little bit of a chore. You have to remove the gas tank just to get to the air filter. But that's not as bad as trying to get to the spark plugs on that bike...but, when it's running right, it's a helluva fun bike. If I don't get it sorted out, it might just become my winter bike and then I'll "summerize" it and store it from May-September.

Thanks,

Will

Does it have a catalytic converter?

It doesn't have a catalytic converter.

Removing the tank, the o-ring on one of the fuel connectors got buggered up. Before I can re-install the tank and go for a spin, I'll need to get up to the store. The way things are going around here, it might be next week before that happens...

After stripping it down and cranking it up, I'm pretty sure there is not an exhaust leak. I'm going to pull the airbox and take a look at the plugs later. I've had some people tell me it could be the oxygen sensors need to be re-set, or it might need a re-map. I'm not convinced that fuel injection is such a great thing...at least for my wallet. Jets and shims are a lot cheaper than a trip to the dealer.

Will

I pulled the plugs yesterday while I had the bike broken down, and took a couple of shots of them. I'm never really sure exactly what to look for in a plug, but what do you guys think? Here's two of them; the third looked about the same as these (and my camera memory card was full).

Thanks,

Will

The plugs are fine.

Those plugs look good,in the past the whole insulator should have been brown but with todays gas formulations they don't color as much or as fast. That tan/light brown color is exactly what you want to see.

Pulled my plugs yesterday for the first time, and they were almost entirely covered with soot. Only a small part of each insulator was still white. Can't believe the bike is running that rich, especially considering much of its life is spent at hwy speeds. If anything, the jetting should be slightly lean. I'm also bothered by the fact that the color wasn't uniform around the insulator. Haven't ever seen anything like that.

Dang, Will, those plugs look just right. Makes me wonder if maybe you pinched a water or oil line in that tumble you took and you have a heat issue in one cylinder.

I didn't see any lines that looked pinched when I had it apart. I did pull the fuel pump plate off the tank and replace the fuel filter while I had it off the bike. Cleaned out a little bit of crud in the tank while I was in there (but not too much). Replaced the air filter, and cleaned some carbon build-up off the throttle bodies. I tried to sync the throttle bodies...but the Motion Pro Pro Sync and I weren't working on the same page last night (it might end up listed in the classified section soon...or the trash can).

So, I just put it all back together and filled it up with fresh gas and took it around the block a few times. It ran great, but the temp was down in the 70's by the time I was out. Supposed to hit close to 90 for the next few days, so I'll see what happens then.

Thanks everyone for the ideas and plug reading help.

Will