!HELP! 1983gs450a Bogged down on the freeway at high revs

[tkent02]

Just a WAG, your petcock is probably not flowing quite enough fuel for the full power operation.

But yeah, you have to do all the other stuff.

[zoso83GS450a]

Ok that all sounds like stuff my buddy and I can tackle. The only two things i worry about are getting into carbs and valves but as the 10 newbie mistakes says i might as well tough it through and do all the work so i know what is not wrong.....i will pay special attention to the charging and fuel/air systems. Thanks i dont know what i would do with out this library of knowledge!

[pete]

And you'll need an impact driver! Not sure if those starter kits include one or not, but expect to use one *a lot* if the sprocket cover and clutch cover etc. haven't been off for 30 years... better to invest in one of those than having to deal with chewed out philips heads...

[mike_of_bbg]

tkent02 might be right about your petcock. You can take your fuel bowl drain screws out and make sure there's a good amount of fuel in there. I might also suspect a gummed up cap vent or petcock strainer. You need to make sure your whole fuel system is clean: tank, petcock, fuel lines, tees, carbs. Even little chunks of rust are like boulders to the tiny passages in your carbs.

Just to follow-up on the tool part:

For most of your maintenance, you'll reach for your 1/4"-drive set with metric sockets from 6-14mm. Most stuff falls in that range. My oil drain plug is an odd sort of size like 22mm, though I can't be sure it's original. The set I linked to should have most of what you'd need, though I'm not necessarily married to Craftsman tools. Mine have lasted over 20 years and saved me thousands in that time.

Remember that this is not a car; it's a motorcycle with stuff threaded straight into aluminum! One of the most common issues is to over-torque bolts and strip threads. Most of the torque specs are in the 3-12 ft-lb range (36-144 in-lbs). Do a search sometime for stripped oil filter cover studs and see how common that is - or oil plugs. Torque wrenches may seem expensive but definitely can save you a ton in the long run.

For your valve check/adjust you'll need the above plus a gasket scraper and a set of metric feeler gauges that go down to 0.03mm.

Impact drivers are handy, though I've not needed the impact until I've gotten under the covers. The screws on your bike are soft steel JIS, or Japanese Industrial Standard, philips. It's different. Getting screwdrivers that fit well is a huge advantage. I have the Craftsman black impact driver set which is about $20, though I rarely need to put a hammer to it. The bits in that set are excellent and grab lots of screws that my other screwdrivers would strip in a heartbeat. Having a access to a dremel and vice-grips helps for the eventual stripped screws.

One reason mechanics usually refuse to work on bikes older than 10 years is the high risk that fasteners will break, strip, etc. and turn a profitable job into a loser. When it's your bike you have the advantage of being able to be patient. Some of your most important tools will be chemicals. Hit fasteners with PB Blaster well in advance of putting a wrench on them; let it soak in and do its work. Use anti-seize thread compound where steel bolts go into aluminum. Berryman's dip cans are great for the carbs. Dielectric silicone compound on those bullet connectors will help keep them from corroding after they've been cleaned.

[850 Combat]

.seeing as how my bike was running fine for 400-500 miles when she bogged down

How old was the oil in it? I think you said you never changed it.

Have you verified that fuel is available from the petcock? It is common for them to fail, and also to clog if the fuel tank is not clean inside.

Have you verified that there is spark?

You described a sound the starter made. Was the motor spinning slowly on the starter? If so, it may not be charging properly. If it isn't charging properly, the ignition will run out of sparks.

There is a lot you need to do in order to narrow down your search as to what the problem is.

[1948man]

+1 on the charging possibility. Since your battery was showing problems
that sounds suspect and just like something I experienced. Bike bogged and died at about 45 mph and wouldn't restart. Regulator/regulator (on bottom of battery box) was fried. You might want to read thru the Stator Papers. Still you need to get used to the idea that you'll be working through the other issues listed above to get the bike reliable even if it does turn out to be a charging issue.