Motorcycles? Yammy troubles

[benscool1]

My buddy has an 80 Yamaha XS 850 Triple Midnight Special that he bought last summer. He and I rode it a bit and it basically sat this winter when he got his car. He has since wrecked his car(got a DUI) and has decided to fix his bike and drive it when he gets his license back in a few months. We've been working on it a little bit but neither of us really know much about working on bikes. Heres the problem: When it first starts up(if you can get it started) it basically won't run at all without the choke on, then when it gets warm it won't run if the choke is on but as soon as you try to give it gas it dies. It idles really low, and it sounds almost like its missing whne you first lay on it(clanging sound, like maybe there could be a dead cylinder) but once it gets into the higher RPMs it is just fine. What could be the problem? Carbs need rebuilt, air/fuel mixture wrong, coils?

And then it won't hold a charge. We put a new battery in it when he bought it, but we have never been able to start it without jumping it or putting it on a battery charger first. What would cause this to happen? I'd assume its the stator or something but I don't have any real idea. What is the problem and how can we fix it?

Any advice would be great.

- Ben

[cableguy0]

first of all pull the carb apart clean it out and rebuild it bike carbs are about as simple as it gets. then just work from there

[chevyhouse]

Before you rebuild the carbs, try syncing them. Out of sync carbs can cause lots of problems and if you say it sounds like a dead cylindar that may be money. I look for the link to instructions......

[chevyhouse]

Step by step for my yamaha, you just have to find your own vacuum ports

http://forums.delphiforums.com/star_...es?msg=60365.3

Making your own gauge

http://www.powerchutes.com/manometer.asp

[Randy70C-10]

Sounds like the needle valve is stuck, when you give it throttle you're "drowning" it with air. This is common with any motorcycle that sits for a while, since the float bowl is so small it doesn't take as long for the fuel in it to gum up (varnish). Hey, it's the man with the same last name is I. Wazzup Ben!!

[dubie]

Originally Posted by Randy70C-10

Sounds like the needle valve is stuck, when you give it throttle you're "drowning" it with air. This is common with any motorcycle that sits for a while, since the float bowl is so small it doesn't take as long for the fuel in it to gum up (varnish). Hey, it's the man with the same last name is I. Wazzup Ben!!

That would be my guess to. Bike carbs aren't very different from ski doo carbs and this has been the cause of a lot of running problems on sleds I have owned. Take the carb apart, clean it out, replaced the gasket(s) and lube the needle.

[benscool1]

Thanks for the info guys, I'll pass it on to my buddy. Heck, I'll probably end up doing a lot of the work anyway. Whats happenin Randy!

[Mudder]

Ben I am sorry I moved this by mistake. Just woke up and thought I was somewhere else. Sorry.

[Randy70C-10]

Just don't do that while you're driving.

[VetteVet]

My Honda 1000 did the same thing every spring when I fired it the first time and all I did was let it run with the choke on for a few minutes until it got warm enough for all the cylinders to kick in. I never had to do anything to the carbs but I did put new plugs in once. Sitting over the winter shouldn't build any varnish in the carbs. If you let it run where it wants to and gradually increase rpms until all three cylinders are firing it should take off and go. If you very carefully touch the pipes after it starts the cold one is the one that either isn't getting gas or spark. Remember I said very carefully?

bike batteries don't hold a charge well after sitting for over a week, they need to be started and run or charged often and always use a small charger. It's easy to overheat and burn out one with a car battery charger.

Vettevet-- Hope my 1100 Virago starts next month.

[68 Stepside]

I had an 83 SECA 750 that had the same prob Ben. The 4 carbs would get gummed up after sitting through an Illinois winter. I was lucky once, and was able to run it full choke, let it warm up, and gradually kill the choke, I then rode it for a while, took it out into the country, and "cleaned the cobwebs out". That worked ONCE. Any other time I had to pull the carbs, clean them, sync them, and go. I'd suggest pulling the carbs and cleaning them as well, it's your best bet. Be sure to sync them when they go back on also.

[benscool1]

OK, all this sounds good to me. He's gonna plan on taking it to one of his family members who is a bike mechanic and have him fix the carbs and everything. It's a fun job trying to get it started at first w/the chocke because the choke lever is broken off, so you have to use pliers to hold the choke on, lol. I think when we take the carbs apart I'm either going to weld a new choke lever onto it, or he may just end up buying a different set of carbs on ebay if worse comes to worse.

So does anybody have any other ideas on what would cause it to not hold a charge now besides the battery? When we start it we usually jump it but as soon as we disconnect the cables it will die, unless we're revving it above 2500 RPMS or so. I thought it could be the stator or something(I don't know much about bikes, like I said so I just assumed) so we took the stator cover off and looked at it, and everything looked fine to us(but like I said, I didn't really know what I was looking for). Everything looked to be in good condition, no loose wires or whatever. The battery was new last summer but now that I think about it, I don't think we followed directions when we initially charged it. I think once you filled the battery up the directions said to let it sit for about an hour or so...well we didn't do that. I think we let it go for about 15 minutes until it said it was fully charged and then put it in. Damn impatient kids, lol. Could that have something to do with it as well?