Choke broken- reason why bike won't start?
 

Hello Guys.

I had my bike, a 98 SH, sitting for over a year in my garage. Yesterday, I drained all the fuel out of the tank. I also drained the fuel out of the carb by using the carb drain screw. Also bought a new battery and fresh fuel. I was very careful in connecting back all the right hoses to the tank especially the little one that goes to the petcock's vacuum port, and turning the petcock CCW to on.

The problem is - the choke end that connects to the carb is broken off, that black plastic nut that screws in to the carb is broken in half and I could see the spring and the actual choke cable.

Will this prevent the bike from starting, or should I say turn over, because of vacuum leak causing fuel starvation? The bike cranks fine, it just would not turn over.

Do you think the petcock diaphragm is shot too causing the same vacuum leak?

Any help or info is greatly appreciated.

Thank you guys.

I think most people consider "cranking" and "turning over" to mean the same thing so I'm assuming your engine does indeed turn over but doesn't start.

It is difficult to start the engine with one broken choke fastener. It is possible to get it running on one cylinder (I've done that) and concievable that if you played the throttle and kept it running long enough to warm it up the other cylinder might start firing.

But what you really need to do is go to the Honda dealer and order the little enrichment valve parts package that costs about $33 and carefully, gently replace the broken fastener.

RK1, thanks for your response.

So, from your input I take the broken choke is preventing fuel from flowing from the tank to the carbs, thus a vacuum leak?

I don't think it has anything to do with a vacuum leak. With no choke on the carb with the broken fastener, the mixture flowing to that carb is too lean and that cylinder won't fire when the engine is cold. The only way you can be sure both cylinders will fire from cold is to replace the fastener so both carbs recieve sufficent fuel to ensure both cylinders fire on start up.

Too little. Too late.
 

" I had my bike, a 98 SH, sitting for over a year in my garage. Yesterday, I drained all the fuel out of the tank. I also drained the fuel out of the carb by using the carb drain screw "

If you drained the tank and carb yesterday, that means it's been sitting with fuel in the carb for about a year.
The choke ( which is actually an enrichening circuit ) can only work if it's jet is actually flowing fuel.
It can't because it's likely varnished shut, as is the pilot jet/emulsion tube/main jet and every other orifice that was submerged in the fuel.

You'll get to clean your carbs, sorry.
While you have them apart you can fix the choke plunger that's varnished into the carb body causing the housing to break when you tried to pull the choke out.

Kai Ju

I broken the plastic nut on my choke a while back. They are expensive little bastards. To keep riding while I waited for the part I put the parts back in the carb and held them in place with a screw. Someday I get around to replacing those parts. :)

choke nut out of a mikuni 32mm carb works, and its brass. hav a set on my bike.

Hi. Would you happen to have the part number?

Thank you.

+1 for that.

Those little bastards broke off on me.