Smoke/Hot engine

[r184120]

Hello guys,

First, thanks everyone for all the help Ive gotten up till now.

This weekend I started working on some low hanging fruit on my 1978 750k. I replaced the break pads, which led to me rebuilding the slave. UGH. But it works great now. The air box when I got the bike was falling to pieces and held together with tape. So, I decided to take it off and add pods. I read all the material I could find, and was ok with the performance loss, and knew I would need to rejet to compensate for the additional air.

Well, as you probably know, the top of the airbox has a hose coming out of it, It looked just like a breather that ran to no where, if that right? Reason I ask, is that I took it for a ride, and although it performed better than I thought, the engine got much hotter than usual, and there was a little smoke coming from the area of the pods. I couldnt tell if from the pods themselves, or the hose.

Has anyone run into this? Any advice? THe pods I got were the foam ones with the spring inside, rather than the blingey cheaper metal cones I see a lot. Thanks guys!

 

[madmtnmotors]

What did you do with the crankcase breather hose that was connected to the stock air box? This vent starts at the valve cover, connects to a separator under the battery box, and then to the air box. This vent hose must vent to somewhere, if even to the atmosphere. If you simply cap this vent hose your engine will overheat. If you left the hose dangling un-capped near the pods then it will indeed vent crankcase vapor that will include some oil smoke. When routed to the stock air box it is recirculated through the intake and is never seen under normal operation.

The separator has a hose that runs down under the swingarm and is typically capped at that point and is part of the routine maintenance/tune up the cap is removed and accumulated moisture permitted to drain. The crankcase ventilation system is clearly described in the shop manual...

Unless you are prepared to put forth the proper effort to tune to pods, then I recommend that you source a replacement stock airbox.

 

[r184120]

What did you do with the crankcase breather hose that was connected to the stock air box? This vent starts at the valve cover, connects to a separator under the battery box, and then to the air box. This vent hose must vent to somewhere, if even to the atmosphere. If you simply cap this vent hose your engine will overheat. If you left the hose dangling un-capped near the pods then it will indeed vent crankcase vapor that will include some oil smoke. When routed to the stock air box it is recirculated through the intake and is never seen under normal operation.

The separator has a hose that runs down under the swingarm and is typically capped at that point and is part of the routine maintenance/tune up the cap is removed and accumulated moisture permitted to drain. The crankcase ventilation system is clearly described in the shop manual...

Unless you are prepared to put forth the proper effort to tune to pods, then I recommend that you source a replacement stock airbox.

Thank you madmtnmotors,

That was a very helpful response. I appreciate it. The hose is still there, just hanging out near the pods I am planning, in the next week to put new jets in and clean the carbs as well as tune them. Do you have other recommendations for me by chance?

As I have seen a number of of this year and model running pods, I am curious how others have routed this line so there isnt just smoke pouring out into the atmosphere as you say. Does anyone happen to know how this is solved?

Thanks again!

 

[amc49]

Run the hose off the valve cover up high to frame and plastic wiretie it to drainback any oil that gets in it, the rest of length then let it fall back to behind motor, say between the swingarm and back of engine, low enough to simply spit on the ground. If you got enough smoke still coming out to bother you like that then engine is in poor condition and needs work.

Did you OIL the foam pods?, they have to be oiled to work.