Bogs down at high speeds

[Rak8986]

Hey guys,

Sorry if this has been answered already but here goes. Today while riding I hopped on the highway to see how my 1980 xs400 did. After about 4 miles going 75mph the bike started to bog down and lose power. After pulling over the bike stalled. After about ten seconds I started it back up and it was still bogging down a bit for about a mile and then was fine. At this point I got off the highway and did about 10 more miles at 55mph and the bike was fine. Most of the driving I do is at 55-60mph range and the bike runs great. I think I need to have the carbs cleaned but is there something else that could be causing the bogging down problem. I was told that my breather on my gas cap could be clogged a little bit and causing it to run lean. Could that be it also?

Any ideas would be great. Thanks again guys

 

[corruptmind]

Could be the floats need to be adjusted. Kinda sounds like the bike is running out of fuel.

 

[ThePsuedoMonkey]

Mine did that once last year when the stations switched to the winter fuel. I tried adding 1/2 a bottle of octane booster just for shiggles, it didn't bog down after that, even without adding the booster during the following fill ups. Sooo it happened and fixed itself...

 

[Rak8986]

I took the bolts out of the bowls and let them drain and now the bike runs great.

 

[Blazernut]

I will have to try that. I can't rev over 6500 rpm without it bogging down. Really a PITA when entering the freeway! I just refreshed the spark plug connections and new plugs.

 

[DanMach]

Something that is overlooked:

Bad petcocks. It can cause a ton of weird issues. My bike had high RPM issues and would sometimes hesitate at or near WOT. I replaced my petcock and its all good now.

 

[Drewcifer]

since it's actually really easy to go into your carbs and clean them out, I'd suggest getting it over with. It's really not hard.

Drewcifer

 

[HoughMade]

Something that is overlooked:

Bad petcocks. It can cause a ton of weird issues. My bike had high RPM issues and would sometimes hesitate at or near WOT. I replaced my petcock and its all good now.

Excellent, excellent point.

 

[Blazernut]

Something that is overlooked:

Bad petcocks. It can cause a ton of weird issues. My bike had high RPM issues and would sometimes hesitate at or near WOT. I replaced my petcock and its all good now.

I just did a carb clean and new jets etc. Petcock seems like the next best bet.