gs850g project bike issues, beginner's perspective

[Busbis]

Hello all!
Two days ago I bought my very first bike, a 1980 GS850g "cafe racer style" that was not running well; My new project. So far I've done some cosmetic things, such as bolting the loose exhaust onto the frame and re attaching the loose gas tank, as well as minor maintenance things (added oil to transmission, filled gas etc...). HOWEVER I have never worked on a motorcycle let alone driven one so far.

I have a few questions on how to get my project running well. My transmission is leaking oil at a pretty significant rate on the brake pedal side only when the bike is running. I'm assuming the oil gets thinned out with the heat and gets spun with the clutch pack? I replaced the gasket on the transmission fill-hole which was literally crumbling, still has the same issue. I have an idea but I will hold it until I see a suggestion.

Second on the agenda, the bike dies after throttle usage AFTER no throttle usage over time. I'm guessing my carburetor has some issues, however I bought the bike with "newly cleaned carburetor" (people lie, the Craigslist seller could have provided false information). For example, the bike sat in my garage for the day, I'm assuming the machine had sat in the prior owner's garage for a while. This morning I let it run for maybe 10 minutes giving it gas in the beginning to even hearing some backfire all in neutral. I tried riding the bike in my lawn about 30 minutes ago and did not get anywhere. The bike died with any and all throttle usage.


Finally, the electronics. I do not even know where to begin when trying to get my electronics to work. The headlight works(high and low), electric start and the left tail light (only one attached). I don't have a speedometer or tachometer attached, but the casing and speedometer did come with my purchase.

Thank you for your time, I can't wait to become involved in the community with my new working bike!
Alex

 

[Guest]

A lot of questions, sounds like the bike needs a good going over. I'm not sure where to begin really.....Maybe the first thing..your bike is air cooled, that means no flowing air and it will heat up until you hear strange noises and your valves start to bend...very bad. I don't let my bike run for more than maybe 5 minutes with out either shutting them off or having a large fan blowing on the engine. Oil does not get thinned out necessarily unless you gas is getting into the crankcase, this may not be happening to your bike but it's simple to test. Take off the oil filler cap and smell.......if it smells at all like gas drain the oil and fix the problem (faulty petcock or bad carbs). I'm not entirely sure which gasket you replaced, I'm guessing it was your clutch cover gasket but a picture would help lots to answer that question. As for the bike dies on throttle, I'd say you have a lot of routine maintenance to do before that question can even remotely be accurately guessed at. Have you looked through Basecliffs site yet? have you seen the thread on routine maintenance? the great thing about anything you're going to have to do to get your bike running perfectly is that you don't have to know a single thing about bikes or mechanics to do it all and the best person to do it is yourself, not a shop, and it can all be done with the help of this site, a lot easier than you would think. Welcome aboard. It might help as well if you put the local area where you live, there's always the chance a helping member might live close by and lend a hand/info.

 

[Brendan W]

I second azr. Here is the link to the site he mentioned http://members.dslextreme.com/users/bikecliff/
It is unlikely that the bike will run and stop safely with only one or two tweaks. There is probably a lot of work to do and the only way is to go through everything methodically. It's pointless trying to diagnose faults otherwise. There is a 'top ten newbie mistakes' thread here somewhere which is very useful.
If I'm reading you right the seal you replaced is an o-ring below the engine oil filler on the top of the right hand case. In front of that is the clutch rod. It's seal can also leak as can the gasket around the side case itself.
There are three oil fill points on the 850. The big one on the right is engine and clutch and gears. The second is on the opposite side by the shift lever and takes gear oil. The third is on the rear wheel hub, again gear oil.

 

[Busbis]

Thank you both, once I do some more working around with the bike and come to some more fine-tuned conclusions I'll ask a few more questions. Until then, I really appreciate your help so far.

Cheers!

 

[80GS850GBob]

Anything to report back on yet? There are a few of us here in Illinois.....

 

[520eek]

Oh...and some pictures! They are always fun!

 

[80GS850GBob]

Pictures are ok...bikes are more funerer...yeah, I said that.

Just remember....pick one thing at a time and fix it, then another.....we got a while before Spring.

 

[loud et]

This is not a stab at you at all, but every person new to bikes has dreams of having the coolest sweetest ride out there....we plan the paint color, the new cafe style seat and the big racing number on the side......
But we never want to start at step one.
My new procedure for new bikes is 1- full carburator rebuild as described on bikecliffs site.That means new o rings(cycleorings.com ) and bench syncing. 2-Intake boots. If your intake manifolds are leaking all you will ever accomplish is burning your exhaust pipes and have a crap running bike. This means buying new intake boots if they have cracks or are separating and new intake of rings (cycleorings.com )
Now you know you have a good fuel delivery system. They whole reason we do those steps is to get it running reasonably well to make sure we can test ride it.
What if you start painting your dream bike and buying all sorts of trick parts and LATER when you finally get it running you learn it pops out of 3rd gear on a hard shift. Or The clutch is just worn and wasted or worse yet there are some other internal broken engine bits.
Point is there are a ton of things to do to get a GS running before it's time to get fancy.
I always end up with all the body and seat off with a good running bike before I even care bout polishing a single part.

 

[loud et]

1- rebuild carbs 14$ o ring kit
2 intake boots or o rings. Inspect/replace. 5$ o rings
3 I hate to say it but do a valve adjustment. Scary at first but it's truly a simple operation and not expensive. Can trade shims here free in the gs shim club.
4 make sure you have spark on all 4.
5 don't even use the petcock and gas tank while you are getting the bike running. The petcock could be faulty and it can give you trouble getting the bike running. Just use a temporary fuel bottle. It gets the tank out of the way and let's you see what you are doing on the bike. Or just spring for a new petcock.
You have various oil leaks, we'll until the bike is running good your will never know the extent and number or leaks and other issues the mechanical part of the bike really has.
It seems like a long road but you just have to do things in the right order.
Just trying to hammer that point home especially because you are new to these old bikes.
Most important like has been said go to bike cliffs site and read. It will all make sense as you start wrenching.

 

[80GS850GBob]

To make an old cycle reliable, the owner needs to address anything that is worn, in need of cleaning {carbs], and in need of adjustment...do this and you'll be fine.

1st suggested order is to thru the carbs....to run right a bike needs fuel {dispensed and metered correctly}, air and spark. I'd check the carb boots for cracking and invest in a set of o-rings that go between them and the head - that way it's sealed. The petcock can bleed air and cause a lean issue with #2 cylinder...add out of adjustment for valve gap and you can trash the valves/seats. Clean out the carbs really well an see how she runs...