Bike won't start ! Yes, another one

[Guest]

Hey guys,

I just registered to this forum because I need help. I have read a bunch of old post regarding GS's (or any other motorcycle) not starting and others about How to troubleshoot a motorcycle but nothing helped.

Here is the story:
I bought my 1980 GS750 3 years ago., I rode all summer and never had a problem with it. Then I stored it for the winter and didn't touch it for 2 years. Now back when I stored it I didn't do anything special to it, other than unplugging the battery. Now fast forward to this year, the bike won't start. So I check the plugs, I get a spark on all four. So I try a little bit of ether, you know to give it a little push. The bike starts but dies as soon as it runs out of ether. So it seems like a fuel problem. Make sense since I didn't put any fuel stabilizer in it before storing it. So it could be 2 things, either the petcock clogged up or the carburetors. I have an automatic petcock so I decide to bypass it by using a bottle of gas and by blocking the vacuum hose. Nothing, the bike won't start and the plugs are still dry. So I decide to clean the carbs. When I open them I realized there already quite clean. No gum, nothing. But anyway since I was there, I cleaned all four. I put everything back and still nothing. The bike won't start and even when I try to flood it, the plugs all still dry.

Other things to mention:
I have change the old gas for new one. The compression looks good but I didn't measure it.

So that pretty much sums it up, any idea ?

Thanks in advance

EDIT: Forgot to mention, I have gas in all the carbs. I have unscrewed the bottom bolt and fuels comes out

[Alexander]

1st, make sure nobody messed with the spark plugs, the long plugs should be on the inside cylinders. In a bike I just rebuilt, someone had switched the plugs on the right side of the engine and I wasted 3 hours. 2nd, if you have spark and nobody messed with the timing, you could be getting air from the carb boots or connection of carb to boots. In mine the boots fell apart and had to get new ones. I assume you pull the choke up and you set your tank on prime just to make sure. Good luck.

[Allie]

It sounds like 1) gas is getting to your carbs. 2) gas is not getting to your cylinders. Therefore either a) there is not enough vacuum to pull gas into the cylinders or b) there is something blocking the gas from being pulled in OR not unlikely c) both.

FUEL
Did you dip the carbs and clean out ever tiny little orifice? How are the o-rings? If something is blocking fuel flow it has to be there.

AIR
-How are your carb boots and o-rings? If they're old and frazzled they could be allowing a mild to severe vacuum leak that would be detrimental to fuel flow. If there's air escaping it's probably there.

- Just for $hits and giggles check your air intake tract. Make sure there is not a family of mice in there blocking airflow, that would also stop you in your tracks. If there is air blockage it is probably there.

Be sure and read the carb rebuild tutorial if you haven't, there's a lot of info that can save you time, money, and loss of life force.

There could still be things wrong that would make the bike run poorly, but your first mission is to get gas into those cylinders, toot sweet soldier!



Those are my humble suggestions.

[llant]

Thanks for the responses,

To Alexander:
All my plugs are the same, is that normal ? The bike was running with them before. Nobody touched the bike since it was stored. The boots are in good condition, the choke was up and I have an automatic petcock on the tank :S

To Allie:
I followed this tutorial for cleaning the carbs : https://www.youtube.com/watch?v=dD3UWtLfzX4. I saw that the guide from this forum is more detailed. I will go over it tomorrow and reclean the carbs. Also, as soon as I am done typing this reply I will go and see if there are any intruders in the intake tract... I really hope it's something like that !

[Allie]

You never know about them varmints. I had a 550 that I was trying to make run. I'd cleaned up the air intake, moved on to clean the carbs etc, and the thing would NOT run. Going over all the things I could have screwed up in the carbs, looking at ignition, the whole works ya know... it turned out to be a mouse nest in the air box that was erected after I cleaned it out. Nice...

On my current bike I had a mouse family living in the neighborhood of the battery box. They didn't bother anything so I left them alone but every time I went out for a ride they'd all come shooting out from under the seat as soon as I put the bike in gear, land in the gravel and scamper off. Next day they'd do the same thing. They eventually moved, they probably got tired of having a home that would r-u-n-n o-f-t on them all the time. Cute little things.

[eil]

Allie's got it right. Clean those carbs!

mrmaxstorey (the dude in the video) is a great laid-back fellow and I enjoy his videos. But the man does not know how to properly clean carbs. Follow the guide in the forum. Get yourself an o-ring kit from cycleorings.com and follow the carb rebuild tutorial to a tee.

Then do the rest of the maintenance, all of which can be found in your Suzuki service manual, see the link to BassCliff's mega-welcome in my signature.

[Steve]

mrmaxstorey (the dude in the video) is a great laid-back fellow and I enjoy his videos. But the man does not know how to properly clean carbs. Follow the guide in the forum.

I did not watch the entire video, then I saw this post. If that is the same guy, we got my son's 850 from him several years ago.

He used to be a member here, I think is username was "Max".

.

[chuck hahn]

Go here.. Look at the right hand side as you scroll down the home page. See the CV CARB REBUILD link??? Hit it. Get a CV oring kit from our member Robert Barr at his website. 1 Kit does the full rack. And while the carbs are off, redo the intake manifold gasket orings. Take yours off and measure the ID of theb groove and order thev appropriate size. His site has the info and pics of the orings so look the place over before completing your order.

http://members.dslextreme.com/users/bikecliff/

http://cycleorings.com/

[llant]

I got the bike started ! I was going to take apart the carbs but I wanted to try one last time... just in case. So I gave the battery a good charge, pull the choke lever and let it try to start for a good 2 min. I was just about to give up and I heard a change in the noise it was making. It started about 30 second later.

I know I should still reclean the carbs but it's a relief that the bike started. At least now I know that I'm not crazy and that the bike works

[Allie]

Great news, so obviously you're getting fuel in there. A good carb dipping and attention to air intake will give you piece of mind, for sure. But don't worry, you can have a running bike and still be crazy. Just look around you at your new 'associates'. lol