TOPIC:

I have two lines coming off of my carb equalizer ports 1 and 3. Not sure what their actual name is but I know they need to be open and aren’t a vacuum port. Anyway, the lines I have run up over the frame and down between my air filter pods. I was pretty sure those lines need to go up before dumping down in case the carbs burp up fuel or something. I am wondering that if those lines one or both get trapped and pinch off during a ride if it would cause the engine to stall like it ran out of fuel?

I’ve been having an issue all summer that I have trouble shooter a few different things and I’m still having the issue. I found yesterday while looking that one of the lines was getting a black skid mark from the tank and a lightbulb went off. I rerouted the lines and they are no longer in the way. Just wondering if it’s feasible that could cause my problem?

The two lines are connectet to the vent ports of the carb bowls and atmosphere, don´t block them with any plug.

Right, but If they got blocked mid ride would the motor shut down ?

Blocked carb vents will cause a partial vacuum in the float bowls leading to fuel starvation at high rpms which will result in a loss of power and eventually cause the engine to cut out.

Also, just routing them to the wrong place can cause ambient airflow to create minor vacuum fluctuations and that can result in jetting changes. Make sure the hoses don't get kinked, but route them to an area of protected air. Preferably up under the tank near where it meets the seat.

I definetly had them routed poorly. When my friend told me to loop them under the tank I didn’t quite think it through. I imagine now it’s much better. No possible way they get kinked now. But that’s what I was wondering. If they were getting pinched it may cause the problem I was having.

Here is how they are routed now

Normally they are routed through that gusset hole, as you have it in the photo, and they stop right there.

Awesome. Yeah I’ve never used that hole until now. Makes sense. I have those lines then dumping down beneath the air pods I run. I’ll cut them so they empty higher up in the better protected air. Thanks everyone

Thank you all for this info. I have a set of Mikuni 33mm smoothbores and have always wondered what those were for. (stupid me).. Are these (in the pic's) vent ports and should they have vent tube lines on them ? They are on #1 and #3 carbs, but as far back as I remember never had lines on them.

Yes. Does your 33's have a accelerator pump?
Steve

Definitely no accelerator pump.

Then what are those four lines about?
Steve