could you post a closer look at yer decompression lever? Mine sits on top.. I'd like to see how yers is configured/bolted underneath..
Sneezles61

Sure looks like when you pull towards you.. then the cable is being pulled also.. I'll forget some times and when I realize its not running right.. The light bulb goes off... close the valve!  Wouldn't it be nice if it did that all by its self?
Sneezles61

If you search there's a whole bunch of debates on where lever "should" be mounted...  kind of like an oil thread. 

The experts seem to agree that mounting on top is "correct"...  promo photos can be found showing both ways. 

"The light bulb goes off... close the valve!  Wouldn't it be nice if it did that all by its self?"

Yamaha thought the same, and fitted the 1974 (DT360A) on bikes with the valve linked to the kick starter.

It actually makes sense to mount it on the right if underneath. 

Like I said, there's been a lot of debate on that feature and what's "correct"...  Yamaha diagrams and photos show multiple variations.

Sooo.. it depends what mood yer in? That depicts the local?  
Perhaps when I do my resto, I'll move it underneath... 
Mauser, yers springs back? Don't need to fiddle with it after it starts? I won't say there is a big difference running with the valve open.. but I can tell when you are loping around and need to get after it..
Sneezles61

Mauser . You have confused the front brake light switch , with the decompression lever assy .
In your defence , it does look similar in the diagram , but they were all mounted on the left .

Since the decomp lever isn't spring loaded you'll want to close it after the bike starts. If you haven't been doing that the valve may not completely close now with carbon built up. The little spring on the valve itself isn't strong enough to spring back the lever. You'll be losing compression and power. My RT3 and RT1 both run differently at startup until I close the valve via the lever. Using new parts and cables too.

Never gave much thought to the effects of it getting gumpuckied up from exhaust.. Makes sense..
Sneezles61

MAUSER...glad it works for you. Pretty small spring on the decompression unit. Maybe I'm running my lever on the handlebars snugged down too much. Anyway, just my experience.