Hey all...
first post here, so go easy. :oops:
heres the scoop. (the short version)
my friend bought a 97 gs500e aobut 2 weeks ago. not having his motorcycle license yet, i was elected to ride his new toy home. it was a salvaged bike, as it had been dropped on the left side, definately a sliding accident (i doubt it cartwheeled). anyway, if i remeber correctly, it has something like 11K on the odometer, and im pretty sure it hasnt had much (if any) preventative maintenance.
on the ride home, i had to fight to keep it going, and it seemed to run out of steam at about 85 - 90 mph, even with a full throttle. it ran very rich, to the point where i could smell gas when i was stopped. i didnt see anything peeing out of the carbs, so i believer the floats were set OK. also, when stopped, it wouldnt idle for crap. i had to keep reving the engine to keep it from dying. and when it did die, it was really hard to start. the other idle problem is that it wouldnt return to idle once the throttle was closed. it would climb to ~4K and then slowly decline to a sputter.
so, im thinking valve clearances are zero.
i pulled the valve cover and tried to check the valves... i couldnt get a feeler gauge in there. i dont remember of the top of my head how small i went, but the clearances are zero, or almost zero. so, i have a dilemma... once i recheck the valve clearances and im expecting them to be zero, how do i order shims when i dont have a baseline clearance between the cam lobe and the shim. should i just go one size down, or should i go 2 sizes down? :icon_confused: i know what to do if i have a clearance measurement, but at zero clearance im a bit unfamiliar.
anyway, enough rambling for now, im gonna have more questions as i work on his bike. im pretty good around a motorcycle, so i should be able to do most anything on the bike. but, i am definately not going to go at this problem blindly and throw money away chasing the solutions.
feel free to ask me to clarify anything, i typed this pretty fast, so i hope it all makes sense.
later...
~mike
get a washer, and take the size of it.
remove shim under cam lob
install washer
take new size, add washer size to the gap you should now have. this will tell you what size you will need.
Welcome!
Quote from: zrxmonkey on June 01, 2006, 01:31:35 PM
On the ride home, I had to fight to keep it going, and it seemed to run out of steam at about 85 - 90 mph, even with a full throttle.
Are both sparkplugs giving spark?
Quote from: zrxmonkey on June 01, 2006, 01:31:35 PM
It ran very rich, to the point where I could smell gas when I was stopped. I didn't see anything peeing out of the carbs, so I believe the floats were set OK.
But gas could be flooding the airbox. Check the float level by using some clear tubing hooked up to the drain spigot of a floatbowl. Hold it up next to the floatbowl, and open the drainscrew, the gas will rise to its current level. If it's over the floatbowl gasket surface it's too high.
Quote from: zrxmonkey on June 01, 2006, 01:31:35 PM
Also, when stopped, it wouldnt idle. I had to keep reving the engine to keep it from dying. And when it did die, it was really hard to start.
Screw in the brass idle adjustment knob, it's hanging down inbetween the carbs. But, there may be more.
Quote from: zrxmonkey on June 01, 2006, 01:31:35 PM
The other idle problem is that it wouldn't return to idle once the throttle was closed. It would climb to ~4K and then slowly decline to a sputter.
This would indicate a lean condition, or an airleak somewhere (which could also allow gas to get by, giving you that gas smell).
And welcome! :cheers:
On the valve clearance questions, see if the "TOO TIGHT" note on this diagram (http://www.bbburma.net/Documents/ValveAdjustmentVideo/GS500_Valve_Shim_Selection_Chart.gif) makes sense.
Quote from: rangerbrown on June 01, 2006, 01:57:27 PM
get a washer, and take the size of it.
remove shim under cam lob
install washer
take new size, add washer size to the gap you should now have. this will tell you what size you will need.
good idea, i will have to remember to do that when i head up to work on his bike.
Quote from: scratch on June 01, 2006, 01:58:05 PM
Are both sparkplugs giving spark?
yes, i pulled the plugs and both have a fat blue spark.
Quote from: scratch on June 01, 2006, 01:58:05 PM
But gas could be flooding the airbox. Check the float level by using some clear tubing hooked up to the drain spigot of a floatbowl. Hold it up next to the floatbowl, and open the drainscrew, the gas will rise to its current level. If it's over the floatbowl gasket surface it's too high.
i have not had a chance to dive into the carb work yet, but the tubing level gauge is usually how i check my vintage bike carbs. i didnt check the airbox for gas when i pulled the air cleaner. i'll check on that next time.
Quote from: scratch on June 01, 2006, 01:58:05 PM
Screw in the brass idle adjustment knob, it's hanging down inbetween the carbs. But, there may be more.
i fidgeted with the idle knob quite a bit during the ride, trying to see if i could find a steady idle point, but i couldnt get it to sit at a good idle speed.
Quote from: scratch on June 01, 2006, 01:58:05 PM
This would indicate a lean condition, or an airleak somewhere (which could also allow gas to get by, giving you that gas smell).
i would agree that the lean condition would result in erratic idle, but the gas smell seems to be due to something else. especially if the air leak is in the carb manifolds. since they are under constant vacuum, i wouldnt expect any fumes to be leaking out, only air leaking in. im not trying to say you are wrong, but it is hard for me to see it that way right now.
thanks for the ideas so far. i know that he really wants to get his bike running the way it should.
is there anything i should be on the lookout for? any common problems to check on?
~mike
Quote from: Kerry on June 01, 2006, 02:05:26 PM
On the valve clearance questions, see if the "TOO TIGHT" note on this diagram (http://www.bbburma.net/Documents/ValveAdjustmentVideo/GS500_Valve_Shim_Selection_Chart.gif) makes sense.
yeah, that note makes sense.
basically, if it is loose enough to rotate, but too tight for the feeler gauge, then you still have some tiny bit of clearance between the lobe and the bucket, and one size down will bring you into the accepable clearnace range. if it is too tight to rotate then the cam lobe is contacting the bucket shim (when it isnt supposed to) and you will most likely have some clearance between the valve and the valve seat... going down two shim sizes will most likely bring you into the acceptable range, and also take up the clearance between the valve and the valve seat.
~mike
You got it. :thumb:
I have seen valves that were 3 and 4 shim sizes off. But like you said,
"going down two shim sizes will
most likely bring you into the acceptable range"[/list]
your going to have to take the shimm out and see what size it is . they only go up and down in .5mm incraments .....