springtime questions

[Nooner]

Last year I purchased a 1981 550-T, I use it to commute when I can. I'm new at the sport and tend to avoid any traffic; as an upstate PA resident, I can manage this.
At the end of last year, I noticed that the bikes performance seemed to fade. Most noticeable was a tendency for the engine to hesitate slightly when I rolled the throttle. I also noticed that the engine would seem to run rough occassionaly. Both symptoms seemed to happen when the engine was hot or cold.
At the end of last season, the problem had grown worse - to the point that it was very difficult to turn over. I put my new baby on a trickle charger, put some sta-bil in the tank, covered her with a nice wool blanket and got my skis out. Spring is here and I am reborn as an old guy with a cycle complex.
I suspect a fuel supply problem and possibly a carbeurator issue. Any help as to how I might troubleshoot? Thanks.

 

[Larry D]

What maintenence have you done ?

And this should be in the tech forum........

 

[Nooner]

not much, I've kept it clean and filled the tires, I am about to start with the maintenance, that's why I posted. I thought this might go under the tech heading, but wasn't sure; sorry about that.

 

[Larry D]

No problem...but, you'd get more answers there.

If you've done any searching and research in the forums, I think you know the answer. Carb cleaning, valve adjustment, no air leaks, etc.....

 

[Nooner]

Thanks Larry, I'll keep searching in the other forums. I was hoping there was a step by step guide that I might follow, similar to the one posted for diagnosing the electrics. I'm not a mechanic, but try to pretend I'm one - so I was looking for a procedure that would take me from the least potentially destrucive fixes toward the most destructive fixes.

 

[gsgeezer]

As mentioned, if you buy and old bike, you're gonna have to clean the carbs!.

When (before) I get one, I check the gas tank for corrosion, too.
If a tank has corrosion, I take it to a radiator place and have it scoured inside and epoxy coated.

 

[Guest]

hi nooner,

have you seen bike cliffs little site? it has LOADS of great info.
http://members.dslextreme.com/users/bikecliff/

as mentioned, start with the valves, and carbs. these bikes will put up with a lot if you address those 2 big issues.....

greg

 

[Larry D]

hi nooner,

have you seen bike cliffs little site? it has LOADS of great info.
http://members.dslextreme.com/users/bikecliff/

as mentioned, start with the valves, and carbs. these bikes will put up with a lot if you address those 2 big issues.....

greg

Also, here's the carb cleaning tutorial from the homepage of this site.

http://www.thegsresources.com/gs_carbrebuild.htm

I was just having the same discussion the other day with Griffin. The first two things that should be done to one of our vintage bikes is carb cleaning and a valve adjustment. After doing these two things, you'll solve some common problem areas and learn alot more about your bike in the process.

 

[Nooner]

Thanks for the sources

Thanks for the sources

Thank You for the sources, had I taken the time to explore the site in more detail, I could have asked better questions. The site with all the pictures is a big help; my mechanical skills don't run all that deep.

I'll start to tackle this job this week and will keep you posted. Who knows, maybe I'll get my gearhead buddies to quit picking on me because I wear a tie to work.

Thanks again, you advise and direction was very useful. I'll keep you posted. Nooner


quote: Life is what happens while you're making your plans.

 

[spyug]

No question you need to do a carb cleaning and rebuild. Not hard just a little time consuming and fiddly. The key is to be organized and work in a well lighted area were you can leave parts out for a day or two without fear of losing them. Don't try and do it all in one fell swoop...a bit here abit there. You may need to a carb rebuild kit if the gaskets and orings have dried or cracked and I'd think Z1 Enterprises would be best for those.

Do one carb at a time if you can and keep all the parts seperate. after cleaning bits and pieces I put them in a zip lock bag and mark them with indelible marker.

If you are going to all the trouble of cleaning the carbs you should look after the rest of the fuel system, so as mentioned have your tank cleaned of any lose rust and clean and rebuild your petcock. You can do tank cleaning and sealing yourself and there are lots of how tos on this. If there is a rad shop in your area it might be easier and cheaper to have them do it however.

If the bike has some mileage on it the valves likely also should be adjusted since this too is a major problem for hard starting. In addition, the electricals in the old bikes get lots of corroded connectors which cause resistance in circuits and can produce weak spark. Clean all the connectors from the battery terminals, fuse block, solenoid and coils at least. When you have more time do the same with all the connectors into the headlight bucket and at the switch gear. When you get familiar with your electricals, a really useful modification is the "coil relay mod" again displayed in great detail on BC's website. This modification will insure you have good solid spark from your coils and helps a lot with hard starting.

Again, don't try to do everything all at once. Put in a couple of hours every other day or so and you'll have it running at peak performance in no time.

Good luck with it.
Cheers,
Spyug