smoke from under the coolant bottle

[oz1961]

I started this thread on another forum but I wanted to change to here to get your ideas and suggestions

I went for a bike ride the other morning and everything was great
When I was nearly home and sitting at the lights smoke came from under the airfilter cover

Last night I had time to strip it down and there was no electrical damage or water pipe leaks and everything was wroking okay

I started it and everything worked and ran fine

BUT

When I got it to working Temperature suddenly I found some smoke

I found it comming from under the coolant bottle

When I removed it I could see a rubber pipe maybe a breather and some somke comming from it

Before I go any further I was wondering

Is it meant to be there?
Is it meant to be connected to anything?

If its breather, is it an engine or gearbox breather?
can I fix the little smokking problem or is it a worn motor?

Maybe there are other questions but your help, like always, would be great

 

[sdt354]

Yes, it vents the crankcase and should be connected to the air box if it's used and you don't want to see the smoke.
Some smoke isn't a worry. After a while motors can develop some piston blow by but still run very well.

 

[oz1961]

Yes, it vents the crankcase and should be connected to the air box if it's used and you don't want to see the smoke.
Some smoke isn't a worry. After a while motors can develop some piston blow by but still run very well.

Okay! I will have a look tonight and see if I can find out where it goes onto the airbox and reconect it.

My bike has only done 8,000 miles but its an 1985

Its the first time I have noticed and smoke so it was a big worry when I saw it first:bang head:

 

[95spfldmax]

It's a bit of a bitch to connect back on to the air box but can and should be done. Helps to have the overflow reservoir out of the way and a pair of oversize needle-nosed pliers.

 

[sdt354]

When I had the air box,I used a screw clamp instead of the factory one. I could, like Mike said, remove the coolant tank and get at the clamp with a long screw driver or 1/4 drive extension. When I put a tee in to vent from the oil cap while still keeping the air box, I put the tee below the carb bracket so I could easily push up on the tee and tighten the clamp. The hose from tee to air box I lengthened. I chose now, to not suck air into my system from the crank case vent anymore. And, run the hose up high by the front of the carbs. The air box makes this about impossible to do though.

 

[oz1961]

last night I pulled the airbox off.
The hose was actually on the opposite side of the connecting bracket for the two rear carbys.
I suspect that the carbs were removed at one stage and when replaced they didnt put the breather hose back on .
I was able to slip it through the other side of the bracket and push it over the airbox pipe when I refitted it
But I didnt have a clamp so I will do that this weekend to make sure it stayes.

I will have a look at other threads to see if there is a better fix as some have mentioned.

 

[MaxMidnight]

I will have a look at other threads to see if there is a better fix as some have mentioned.

Use thick walled heater hose which is self supporting and only needs guiding onto the air-box spigot as you push it down. A couple of Jubilee clips to make sure it is oil tight.

 

[dannymax]

I never ran a clamp with the stock airbox, just held the tube in place with 12" hemostats and lowered the airbox onto it....it always stayed in place.