Bike perrforming poorly

[djg42]

The last couple times i took my bike out it has seemed slower than usual, just feels like theres a decrease in power. Its cold here, this winter Ive been taking it for short rides(30 min. once or twice a weekend). I took out out today, stopped in at the store, then it didnt want to start. I put it on prime for a second, and then it started up. Um not sure if its just the cold weather effecting the performance, or if all these short rides ive been going on have caused it. What do you think? Any suggestions would be greatly appreciated!
DG

[Big T]

It could be a lot of things, but short, cold rides are just bad for your bikes.

I'd start by checking your spark plugs and changing them if they look black (or post up some pics)

Then, take it for a long (20-30 min) ride and runs it up to redline a few times

[Dave8338]

How many miles on the bike?
Valves adjusted?
Petcock on its way out, starving for fuel?

When the temps dropped here the first year I got my 650 rolling, I ended up shiming up the slide needles about 1/2 notch, just to keep it from bogging slightly in the midrange.

[djg42]

Theres 10,500 miles on the bike. I would like to learn to adjust the valves anyway, so im going to try.
The drop in performance seemed to drop pritty quickly though, if the valves need to be adjusted would it occur gradually?
What is the method to check the petcock? Thanks again!

[duaneage]

I vote petcock. Drive it on PRI and while cruising along go to On (or RES) and see if it acts up. The diaphram inside the petcock goes south after a few decades, Also the rubber hose from the carb to it gets leaky, and that affects the bike running well just as much as the petcock.

Pull the petcock out of the tank (messy but doable) and see what the screen looks like. Maybe it's gunked up.

[djg42]

thanks will do! I have noticed some gunk on the engine, cooud have been leaking gas,

[sscott]

Not meaning to hijack this thread but asking a question. If the diapram is going bad would there be gas in the crank case? Just asking for trouble shooting reasons. Thanks!

[djg42]

It was a nice today so I took it out for a ride, tried switching it on PRIME- and the bike was back to its old self again, guess im gonna need a new petcock?

[tkent02]

Take it apart and clean it.

[djg42]

is it necessary get a petcock repair kit or can I just clean it? Thanks again,
DG

[duaneage]

It depends on the condition of the diaphram on the side. Open it up and see. I would rebuild it to increase confidence in the bike.