New rider, new bike!

[1034am]

I can't speak to GSJack's specs, but i just did my shims this weekend. I used a medium crow bar and inserted it between the cam lobe and shim, from the inside angle. (I needed it for the leverage, my buckets were really hard to depress.) When you get it depressed, insert a large flat head screw driver, w/the head sideways, between the cam lobe and the bucket (the outer rim.) That will keep it depressed, use tweezers and a magnet to fish out the shim. And put a rag in the center to keep shims from falling into the crankcase.
Good luck!

[EdChen]

I believe you're correct on the specified tolerances, but gsJack's ridden many miles and been through more GS500s than most, and in his experience, setting the exhaust valves on the loose end (even looser than spec) has worked well. If I recall correctly, on his early GS, he put them right to spec each adjustment and that ended in excessive wear, to the point that at the end of that engine's life, there weren't shims thin enough to set the clearance properly.

I can attest that my valve shim combination allowed me to put the space at either .06mm or .11mm and I went with 0.11mm, and after 5k miles, I went back in and all the clearances were just about exactly the same as it was. Bike runs great.

Here's the screw driver gsJack uses:
http://gstwins.com/gsboard/index.php?topic=35746.0

[SonofBochy]

Alright, thanks again gentlemen. I think I'm just gonna purchase the actual shim removal tool from somewhere just for my peace of mind that I'm doing things right.

At the same time, while I'm at it... I might as well purchase a repair manual. Is there a big difference between the clymer and the Haynes?

Thanks


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[bombsquad83]

By experience members here have found that running the exhaust side somewhat looser (0.08-0.13mm) extends the time between shim swaps with no noticeable impact to performance.   I second the opinion that your clearances are good, no need to swap them out at this time.

If you do ever need to do a swap, I recommend buying the tool.  I tried with a screwdriver, and while some have been successful, I found it to be too cumbersome for me. 

[bmf]

+1 for the shim tool.

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[ShowBizWolf]

(a little late to the party but...) Just wanted to say welcome to the site and congrats on the bike!! Another informative thread that was fun to read through... 

[SonofBochy]

Alright, guys, I thought I had a possible breakthrough and that one of the previous owners switched the fuel lines up. I'm really confused now... I was hoping to clean these lines out with an air hose but I want to make sure I connect everything CORRECTLY.

BaltimoreGS' video on valve clearance check and adjustment shows removal of the two fuel lines connecting the gas tank petcock to the frame-mounted petcock as being connected to the PRI and RES positions. Here's the video: https://www.youtube.com/watch?v=GWrlaIafIAU&feature=youtu.be&safe=active
skip to 2:00 in to see what I'm talking about.


But this page on the hose routing says that the lines connecting the gas tank petcock connects to the Main (on) and Reserve positions on the frame-mounted petcock. Here's the page http://www.gstwin.com/fuel_hose_routing.htm

I've only disconnected the two fuel lines that attached to the gas tank petcock. The Reserve was definitely one of the ones disconnected, but the other one, I'm not so sure; that one non-reserve line was disconnected from what looked like the PRI plug-in on the frame-mounted petcock. The lines that were left after removing the tank were attached (on the FRAME-mounted petcock) from what looks like the on position to the lower T connection between the carbs, and the vacuum hose going to the RIGHT carb (this is different from the fuel hose routing page where it says the vacuum hose connects to the LEFT carb).

I have a suspicion I'm over thinking this and should just attach everything back to where it came from, but if these lines were mixed up, could one experience the fuel starvation problems I was having? I'll post a picture of the frame-mounted petcock in a minute.

[SonofBochy]

Lines left after removing fuel tank:






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[EdChen]

I'm not sure I totally understand the issue, but basically, the gas tank has 2 hoses, the main fuel outlet, and the reserve fuel outlet (only difference is that the reserve nipple draws the fuel at a lower point in the tank).

From there, they go to the frame petcock. The frame petcock has 2 fuel inlets, the main fuel connection, and the reserve connection. It has one outlet that goes to the carbs. When knob is set to ON, the fuel comes from the main connection to the tank, then gets stopped by the vacuum operated valve. When it's set to RES, the fuel comes from the reserve line, then gets stopped by the vacuum operated valve. When it's set to PRI, the fuel flows freely from the RES outlet straight through the frame petcock.

This link might describe it better/differently: http://wiki.gstwins.com/index.php?n=Upgrades.Petcock

Routing Info here:
http://wiki.gstwins.com/index.php?n=Main.HoseRouting

The hose routing, for the most part, shouldn't affect the running of the engine and the operation of the frame petcock. As long as the frame petcock fuel outlet is connected to the carbs, and the tank is connected to the two inlets (can be switched), it should be ok. Even if it was switched around, switching to PRI and/or opening the fuel tank cap would still work to help diagnose the problem.

[SonofBochy]

got it. long story short, im just an idiot. still learning. thanks.

[SonofBochy]

Please delete

[SonofBochy]

Ok guys, got everything put back together, new battery filled and charged and installed works great. Still having the same fuel issue I was having before. I filled the gas tank, went for a run and 5 miles in have the same problem at the same exact spot after a 50-55mph run for maybe a mile or two mostly downhill.  I switched the Petcock over to prime and it's still happening. The bike idles completely fine (although a bit low at 1,000rpms). While its idling I can throttle the engine up very responsively once or twice, but the third time it isn't as responsive, so it struggles and dies.

Is it time to take out the carbs and clean and rejet?

Maybe put seafoam in first? There is an aftermarket K&N air filter in there and I have no way of knowing whether or not the previous owners rejected afterwards

[Slack]

Did you try opening the gas tank cap when it happened to see if it fixed the problem?
If that didn't work I would clean out or replace (with a manual non vacuum) the frame petcock. The site has a "how to" somewhere on how to clean out the petcock, if you don't want to swap it with a manual one.
It shouldn't be the carbs, it really sounds like fuel starvation.

[SonofBochy]

I did try opening the tank, it didn't seem to do anything and I didn't hear any air rush into it when I opened.

So after switching to prime and making sure the tank isn't a vacuum, you're saying the next step should be to clean the frame Petcock, instead of the carbs? I guess that makes sense since it's the first place after the tank that stuff could get clogged up...


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[EdChen]

You could bypass all that stuff and just see how well the fuel flows. Maybe pull the fuel line from the carb and see how well it flows into a bucket?

[SonofBochy]

Switching to the manual non vacuum Petcock might be best.... Anyone know of a good replacement one for under $50?


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[SonofBochy]

EdChen, good call, thanks. I tried that and fuel flowed freely when the Petcock was set to the prime position, but trickled to almost a complete stop when on main or reserve positions... So what does that tell me exactly?


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[Slack]

That's tells you that at least the prime pathway is clear.  The engine has to be running for on/res to work. Do all you future tests/riding in prime. Then if we can fix the bike in prime, and it starts happening in on/res you had 2 problems. But DON'T leave the bike in prime between rides!!!

If you still want to upgrade a honda cr250f (i think that's it) fit's well with just a little bit of quick dremel work.

I still think the problem is that your fuel bowls aren't filling quick enough. We just need to figure out why. To test this you could get a short piece of clear hose, run the bike until it stops working right, and quickly check both fuel bowl float heights. If one or both are way low and slowly fill up, you know there is a clog somewhere.

Wait a sec...  I think I remember reading about someone who had a coil go out once. It would work when cold, but as it warmed up something stopped working right. 

[SonofBochy]

http://www.gstwin.com/float_height_check.htm

You're talking about this test, right?


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[Slack]

yep. try that before and after the bike starts having problems and see if the levels differ.