Bros question!!!!

xseanx

This is my first bike which i love to bits.
At the minute im having a choke problem, which i think is making my bike run to rich. Im using a lot of petrol and when i rev hard, black smoke comes from the exaust (not blue). Today i went for a ride up the sallys gap and it seemed to be not putting out any power and there was a strong smell of fuel from the exaust, so I end up turning around and going home.

Can anybody shed some light on whats going on.
Could it just be due a good service and a new choke cable?

Cheers.

thehomeofDob

Can you explain how you're using the choke? The choke on the Bros I had never worked right, which was a mighty pain in the winter. How long do you leave the choke on after starting the bike? At this time of year and on a day like today it shouldn't need to be on for more than a minute or so. After that you'll be running rich.

xseanx

So should the choke be totally off and the nut under the tank be closed or open when I'm driving? I'm new to bikes so sorry if I seem a bit slow. But I do appreciate your reply. It just seems like when I'm using the choke lever it has a mind of its own and I really just have to use that nut to let more fuel in.

Peanut2011

You use choke to start the bike. The minute engine starts warming up you close it. At the moment for me the choke would be on for about 2min max. That is the time it takes me to get out of the estate on a main road. After that throttle is out and no need for choke.

xseanx

Peanut2011 wrote: »

You use choke to start the bike. The minute engine starts warming up you close it. At the moment for me the choke would be on for about 2min max. That is the time it takes me to get out of the estate on a main road. After that throttle is out and no need for choke.

Ok thanks. So what way should that little nut be?

Idleater

xseanx wrote: »

Ok thanks. So what way should that little nut be?

Iirc the little nut switches between reserve and normal. I don't remember which one is which but horizontal is off.

It should say on it but you don't want to be driving normally on the reserve setting unless you like walking in bike gear :-)

CJhaughey

The nut you speak of is the fuel tap I think, that should be in the On position There should also be a Reserve and an Off position that you should use when parked.
It sounds to me like the same thing that you hear this time of year with any engine that has been parked up with fuel in it.
The fuel absorbs water and evaporates over time leaving behind deposits, these could be a kind of varnish or a green slime or sometimes corroded alloy dust.
Any or all of these deposits eventually block the carb internals, jets or galleries leading to the kind of issues you have described.
If the jets are blocked then the choke will allow the engine to run (badly).
The only way around it is to clean the carbs and refit.
Best to drain the tank and fill with fresh fuel as well not a mix of old and new fuel.

xseanx

CJhaughey wrote: »

The nut you speak of is the fuel tap I think, that should be in the On position There should also be a Reserve and an Off position that you should use when parked.
It sounds to me like the same thing that you hear this time of year with any engine that has been parked up with fuel in it.
The fuel absorbs water and evaporates over time leaving behind deposits, these could be a kind of varnish or a green slime or sometimes corroded alloy dust.
Any or all of these deposits eventually block the carb internals, jets or galleries leading to the kind of issues you have described.
If the jets are blocked then the choke will allow the engine to run (badly).
The only way around it is to clean the carbs and refit.
Best to drain the tank and fill with fresh fuel as well not a mix of old and new fuel.

I don't think it's the fuel reserve because when I adjust it, the revs increase.

Wossack

idle adjustment? sorry dont have a bros myself

CJhaughey

xseanx wrote: »

I don't think it's the fuel reserve because when I adjust it, the revs increase.

Is it a black plastic knurled knob?

xseanx

CJhaughey wrote: »

Is it a black plastic knurled knob?

Yes man

Alkers

If it's the idle adjustment your fiddling with, you only need to set that once then you can leave it alone. Once your bike is warmed up, leave it tickover in neutral and adjust it so the rpm is around 1,500 (not sure what it should be for a BROS but somewhere in that region), you only need to adjust it if your bike it cutting out at idle or revving too high at idle.

xseanx

Simona1986 wrote: »

If it's the idle adjustment your fiddling with, you only need to set that once then you can leave it alone. Once your bike is warmed up, leave it tickover in neutral and adjust it so the rpm is around 1,500 (not sure what it should be for a BROS but somewhere in that region), you only need to adjust it if your bike it cutting out at idle or revving too high at idle.

Ok so my choke should be off when warmed up and that idle knob should be adjusted so the bike is at 1500 revs, when idle. correct?

Alkers

Yes, then you don't need to go near the knob again unless you're cutting out or revving too high when at idle.