Getting Her Going

bul_racer

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I've been working (slowly) on getting my 1980 650SG running again after many years of neglect. Finally got it started but it doesn't want to rev up. I've cleaned the carbs & replaced all the rubber parts within. Adjusted valves, got a new battery. Sprayed carb cleaner into the cylinders and compression was 117-125, which is not great but should be enough to run OK. Any ideas why it won't rev? I'm a 2-stroke guy so don't know much about 4-strokes. If I put my hand over carb intake on a 2-stroke it has strong suction but there's barely any suction when I put my hand over the XS650 carb. Is this an indication of a problem? I do not have air filters on. Not sure if that makes a difference.

Thanks for any insight!
 
OK, I'm an idiot. Looks like maybe it was a loose spark plug wire. Shouldn't be loose but...
Next question: is there any way to get the cover off of the speedometer?
 
Good on you getting R going!
There is a vacuum port on both intakes, stock one connects to the vacuum petcock the other is capped (or should be). Cracked or missing caps happen.
vacuum petcock.jpg
 
Good on you getting R going!
There is a vacuum port on both intakes, stock one connects to the vacuum petcock the other is capped (or should be). Cracked or missing caps happen.
View attachment 242981
Gary, I had so many problems with the petcock that I took it off and replaced it with a regular gravity one. I don't think that can cause problems... Right?
 
OK I have disassembled the tach using the technique recommended by RustyPyles, with a thin grinding wheel around the circumference of the housing. It went OK... Sort of. I have a couple of questions though. First, the pointer has broken. I will replace it by epoxying a new dial to the base. Do I need to do anything special as far as remounting the dial, such as pre-winding the spring or anything or just put it on there pointed at 0 MPH? Also, seems everyone is out of stock on the little light bulbs that go in there. Found a couple on ebay wanting $10 apiece but being the thrifty person I am I'm not keen on paying 400% markup. Wonder if anyone can recommend a more reasonable source?

One more thing: When Rusty posted his repair thread he was not sure that his exoxy would hold up to the bouncing and vibrating. I did not see any update so would like to know if Rusty might see this or if anyone knows if Rusty's or others who've done this repair know whether it has withstood the test of time.

As always, any insight is appreciated,
Kruser
 
LED replacement bulbs are all over eBay cheap, both the push-in type and the twist-lock type. I'm pretty sure your '80 uses the twist-lock kind, what's called a BA9S bulb, so search for that .....

BA9S Bulb Base.jpg
 
My tachometer has 1 screw missing. My hardware store doesn't have anything that small. Looks like maybe 2mm. 3mm was too big. Anyone know where I can get one of these screws?
 
My tachometer has 1 screw missing. My hardware store doesn't have anything that small. Looks like maybe 2mm. 3mm was too big. Anyone know where I can get one of these screws?

Dont know what screw it is .And there are many variants M2 M2.5
But since you got one .A computer store can have something that small / Electronics.supplier
Here in Europe Kits are available with different lengths and sizes .
So one buys that box a 6 -- 7 $

Skruvar: 20x M2,5x12 mm, 20x M2,5x19 mm, 20x M3x12 mm, 20x M3x19 mm och 10x M3x25 mm. Muttrar: 40x M2,5 och 50x M3.


1684792548784.png
 
Dont know what screw it is .And there are many variants M2 M2.5
But since you got one .A computer store can have something that small / Electronics.supplier
Here in Europe Kits are available with different lengths and sizes .
So one buys that box a 6 -- 7 $

Skruvar: 20x M2,5x12 mm, 20x M2,5x19 mm, 20x M3x12 mm, 20x M3x19 mm och 10x M3x25 mm. Muttrar: 40x M2,5 och 50x M3.


View attachment 243546
Thanks Jan! I took a screw out of my laptop. It was the same size but the thread was different. Haven't been able to get to a computer shop yet. Maybe tomorrow.
 
My tachometer has 1 screw missing. My hardware store doesn't have anything that small. Looks like maybe 2mm. 3mm was too big. Anyone know where I can get one of these screws?

The face of the tacho?

Disappointing no one offered a source for the tach screws. Guess I can tap in a larger screw but rather not do that if I don't have to.
Request was buried in a thread with a generic title? Few would have one of those screws laying around loose to measure.
 
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The face of the tacho?


Request was buried in a thread with a generic title? Few would have one of those screws laying around loose to measure.

I'm a bit confused; 9 out of 10 guys open their gauges by straightening the crimped flange, many threads detail the procedure, you dremeled the flange off?
Gary, Thanks for your response. OK, you're saying I should have created a new thread. I'll take that advice for future posts. Wasn't thinking of someone having the screw lying around but maybe remembering where they'd gotten one.

Yes, I saw lots of posts discussing how to get the cap off but I didn't see any that looked like what I have and I didn't see any way to pry the cap off. I didn't see a crimped flange. More like the cap is pressedd onto the plastic part. I figured I could have jammed something into that tiny space but I was afraid I would destroy it in the process. There's just no room between the plastic frame and the cap.

When I saw the post about cutting the plastic to allow removing the cap it seemed like a good idea. Wasn't too hard to do. It's a small kerf so putting it back together shouldn't be a problem, if I can find a suitable screw. It looks like the screw is 2mm but not sure of the thread since it wouldn't take the one I pirated from my laptop.

Sorry, I should have put up pictures to start with.
 

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Gary, Thanks for your response. OK, you're saying I should have created a new thread. I'll take that advice for future posts. Wasn't thinking of someone having the screw lying around but maybe remembering where they'd gotten one.

Yes, I saw lots of posts discussing how to get the cap off but I didn't see any that looked like what I have and I didn't see any way to pry the cap off. I didn't see a crimped flange. More like the cap is pressedd onto the plastic part. I figured I could have jammed something into that tiny space but I was afraid I would destroy it in the process. There's just no room between the plastic frame and the cap.

When I saw the post about cutting the plastic to allow removing the cap it seemed like a good idea. Wasn't too hard to do. It's a small kerf so putting it back together shouldn't be a problem, if I can find a suitable screw. It looks like the screw is 2mm but not sure of the thread since it wouldn't take the one I pirated from my laptop.

Sorry, I should have put up pictures to start with.
So I'm that guy that has one "laying around".
Measured at d=2.17mm 5mm long
speedo screw.jpg

Pitch, oh man my eyes ain't good for this but .35 too fine .5 was too coarse so .4 ?
maybe .45 is a standard.
With an SAE gauge 60 TPI was the closest so that's pretty near the .45
meanwhile I lost the damned screw. :banghead: o_O
EDIT: Found the screw! now just got to get it back where it belongs in TSOIR

1684977357840.png
 
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