I'm new to the site and know this thread is almost a year old, but I am just starting to install a Vape system on my 71 RT1. MarkT's posts have been VERY helpful. The one question I didn't see clearly answered here or in the instructions are that in order to retain the original operation of the lights (only with key in lights position and engine running), should the stock rectifier be retained? The instructions say to alleviate it and jump the wires, but the posts above say it may be needed to keep stock functionality. Thanks.

I think I was pretty clear in Post #2 of this thread. 

Just remember there are at least half a dozen methods to adapt the VAPE to your RT1.   Each one is like a "recipe" that has different outcomes.  A mistake many people seem to make (in my opinion) is they use bits and pieces of various "recipes" (instructions) and wonder why they end up with something that doesn't work out. 

That would be like using a cookbook to bake a chocolate cake but using some of the main instructions from an apple pie recipe.  I'd never say don't try something like that if you are an experienced cook with knowledge of what you're doing because you might end up with an amazing new dessert!  But what you get is not the chocolate cake of the original recipe OR the apple pie of the other recipe. 

P.S.  VAPE has various versions of instructions...  most are "generic" and may not get everything working on your Yamaha properly even if you follow them exactly...

For example some VAPE instructions reportedly will say to use a relay for ignition kill (which you don't need on your bike).  Their instructions are just very basic and meant to be used as an "aid".  An experienced cook can follow a "generic" recipe and will know when ingredient swaps are okay or even needed.

 

Yes, you absolutely covered a lot things that were very helpful in your posts. The one thing that I couldn't get clarity on (and I read them several times) was the need for the stock regulator or not. I've done several restorations, including 74 DT360 before this RT1, but electrical wiring is not my strong suit and this particular part has me baffled. Thanks.  

Edit - think this part of your post says to keep the rectifier, I just want to verify:

 If you leave the original rectifier in place, the headlight will only work with key in the "lights on" position and engine running.  . 
 

Rectifier, not regulator. Sorry.

Yes, if you wire the VAPE output wire to the yellow and greens where the original stator connected, leaving the rectifier (just a diode) prevents the battery from "backfeeding" the headlight yellow wire. 

Stock Rectifier left in place- headlight will only work with engine running.  (If you have an early "plate" rectifier, I'd suggest using the later rectifier version or bypassing)

Rectifier bypassed- battery will be able to feed the headlight with key in headlight on position even if engine quits. 

On the early models like yours, it's not as critical a choice as you have the key switch to kill the headlight. 

Later US models (starting around 1978) do not have any kind of headlight on-off switch so if you follow the method I described and bypass the rectifier the headlight will be on all the time...  (ALL the time, at least until battery dies)  Unless you add a headlight on-off switch.

perfect-thanks for the quick reply!