Adding a primer system

fourbarrel

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Has anyone every successfully added a primer to the carb rack on a Yamaha triple?I remember reading some time back about having to drill a hole for a spigot or whatnot but wondered if there was an easier less invasive way to do it.My cousin and I added a plunger type to our friends Mach Z,but the flatslide rack on that sled had a factory installed spigot installed already,all we had to do was pull the cap off and slide the gas line of. It worked like a charm.
 

IMO the starter circuit is much better than a primer. All a primer system does is squirt fuel into the air horn. Very little of it actually atomizes. As long as your bowls have fuel and the starter circuits are clear, it should pull fuel through the starter orifice as it turns over. Are you attempting to correct another issue, or do you really want a primer system for some reason? I have never seen an inlet on the TM carbs Yamaha uses so either I simply have missed it or you would have to drill and tap one in.
 
I wonder if you might be able to add something to the reed spacers? Just an idea. Drill and tap a barb in the spacer. And then you would have to tie your primer into the fuel system.
 
I have to say the thought of a primer on my mtn max has crossed my mind. It's not a hard starter, 2 maybe 3 pulls even on the coldest days. When it fights me is after I've been away at work for 2 weeks.

I have been getting spoiled with the primer on my 700 poo twin. That was a factory installed system. I added a system on my doo 500 fan. Same deal round slide mikuni's with the primer nipple already there. That is a piston port motor and it's a bear to start after sitting any length of time without the primer. It's been a life saver on that sled.
 
One thing to note is that for the starter circuit to work well the throttle needs to be at idle. On a mod sled the idle might be high which actually causes the overall starting mixture to be leaner and thus possibly difficult to start.
 
I have 2 sleds here that someone added a primer to. They drilled and siliconed lines into the reed boots on 2 of the cylinders. Sure is noce for the first start of the season or after a trip up the mountain on the trailer. pump till I feel fuel going thru and then starts first pull evertime. I have wondered about airflow blockage of the lines where they are but have nothing to compare to. I would sell you the one setup cheap if you wanted to try it..
 
I have 2 sleds here that someone added a primer to. They drilled and siliconed lines into the reed boots on 2 of the cylinders. Sure is noce for the first start of the season or after a trip up the mountain on the trailer. pump till I feel fuel going thru and then starts first pull evertime. I have wondered about airflow blockage of the lines where they are but have nothing to compare to. I would sell you the one setup cheap if you wanted to try it..

It's funny you mentioned adding lines to the carb boots because that's exactly the sort of thing I had envisioned doing.Actually I thought about a small 90 degree brass elbow sealed into the boot with a gas line going to it from a plunger.I'm thinking a person would only need to do one because once the engine fires the other 2 will pick up,mine usually does anyway.
 
The first SRX I bought was a '99 from a buddy of mine. He had a primer bulb from a boat in the hose going from the tank to the pump. I thought it was kinda shtunky at first. After I cleaned the carbs and went to start it for the first time, I pulled like a mad man. Then I remembered the bulb. I pumped it until I saw fuel moving in the lines. Three pulls later she fired. Just my $.02.
 


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