1987 Yamaha Radian starting issues

Hi Evan,

I’m having some issues with my Radian. It sat for about a year in an unheated garage and it didn’t start when I pulled it out (as expected). The fuel had stabilizer in it, but the battery was also in it during this time.

So far I’ve:
– pulled and recharged the battery on a trickle charger, water level is fine
– replaced the spark plugs (the old ones looked fine, though)
– drained the old gas from the tank/carbs and put in new gas (with a bottle of seafoam mixed in)
– carbs #1 and #2 are receiving little/no gas

The bike wouldn’t start from the (recharged) battery or by jumpstart from a (turned off) car. If I hold the start button it chugs and visible exhaust comes out of the right-hand pipe (fed by carbs #3 and #4) and I can feel exhaust from the left-hand exhaust pipe.

So, what next? I don’t think I can avoid pulling the carbs and cleaning them up (I found this forum through your guide), but could this be caused by something else? The left two carbs are receiving fuel – shouldn’t the bike start if everything else is in order?

Is it necessary to ‘adjust’ the carbs in order for the bike to work (assuming everything else is working)? Do those adjustments just make the bike more efficient/less rough or are they necessary before the bike will start?

Please let me know if I’ve left any necessary info out. Any and all advice is appreciated!

Misc notes:
– I tried starting with the choke all the way out and all the way in, no dice with either.
– The battery read 13.6 after the charge and about 12.6 after a couple of start attempts.
– I set the petcock on prime to test if gas was going to each carb (by opening the drain screws). On Prime, when the drain screws were closed, the gas would come out in a steady stream from an overflow tube near the rear wheel. Is this supposed to happen?

Thanks! Also, amazing website!

Hi Ant –

Definitely sounds carb related to me. Technically, yes, if 2 of the cylinders are getting fuel than it ‘should’ start, but not necessarily. It would run like garbage anyway.

When gas is coming out from the overflow tubes by the rear wheel that is an immediate signal that the carbs need to be opened up. That happens due to stuck/sticky floats which are not properly metering the level of fuel entering the carbs. Chances are, if the floats are gummed up, so are the jets and needles.

Pull those carbs and give them a clean.

When storing the bike in the future, disconnect the fuel hose and put a cap over it. Then drain the fuel from the bowls of the carbs using the drain screws. Store the bike with the carbs empty so there isn’t fuel to evaporate. Over the course of a season it WILL evaporate and gum things up.

Let me know how it goes!


Evan Fell

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