Confirm my thoughts, please.

[Hermit]

Ok,

1) From day one (that I got it, mid July) my 1979 GS750 has had a leak. It leaks gas from the #3 (assuming that while sitting on the bike, the left-most carb/cylinder is #1) little drain tube thingy from under the carb. From what I can/have seen, it does NOT leak from the other tubes/carbs. Is that a petcock problem, or is it carb related?

2) Front brake pulsates, but in a grab-release-grab-release etc...pattern. Out of true front disc?

3) Black schmoo (oil) around the finning where the head and "barrels" meet is evidence of a blown/bad head gasket, correct? AFAIK, the bike isn't burning oil, my wife didn't notice any smoking from the exhaust while following me recently.

4) Where my tach cable screws into the engine/head, oil kinda leaks/sprays out. Minute amounts that, when hot, make a sorta bubbling mess. It's small, but makes a mess. Is there an o-ring in there that might need replacement?

Thanks. This site is tremendous.

[Anonymous]

1) From day one (that I got it, mid July) my 1979 GS750 has had a leak. It leaks gas from the #3 (assuming that while sitting on the bike, the left-most carb/cylinder is #1) little drain tube thingy from under the carb. From what I can/have seen, it does NOT leak from the other tubes/carbs. Is that a petcock problem, or is it carb related?

Check the float bowl drain screw (the screw that blocks off the drain tube). It could be loose, letting some fuel escape. Possibly you have a leaking petcock, but your carbs should not overflow fuel any way. It may fill your crankcase with fuel, but it should not get onto the ground.

2) Front brake pulsates, but in a grab-release-grab-release etc...pattern. Out of true front disc?

Sounds like a warped rotor. If the frequency of the pulsing changes with road speed, it is almost certainly a warped rotor.

3) Black schmoo (oil) around the finning where the head and "barrels" meet is evidence of a blown/bad head gasket, correct?

I wouldn't say blown (your bike will run like garbage if at all with a truly blown gasket), but it is not sealing the oil perfectly. You can try re-torquing your head bolts to see if that does it, but the fix will likely be a new gasket.

Don't know about #4.

Mark

[Anonymous]

Re: Confirm my thoughts, please.

Ok,

1) From day one (that I got it, mid July) my 1979 GS750 has had a leak. It leaks gas from the #3 (assuming that while sitting on the bike, the left-most carb/cylinder is #1) little drain tube thingy from under the carb. From what I can/have seen, it does NOT leak from the other tubes/carbs. Is that a petcock problem, or is it carb related?

2) Front brake pulsates, but in a grab-release-grab-release etc...pattern. Out of true front disc?

3) Black schmoo (oil) around the finning where the head and "barrels" meet is evidence of a blown/bad head gasket, correct? AFAIK, the bike isn't burning oil, my wife didn't notice any smoking from the exhaust while following me recently.

4) Where my tach cable screws into the engine/head, oil kinda leaks/sprays out. Minute amounts that, when hot, make a sorta bubbling mess. It's small, but makes a mess. Is there an o-ring in there that might need replacement?

Thanks. This site is tremendous.

1) It's a carb problem. You'll have to check the float hight on carb #3.
Also check the float needle. It might be worn and not closing correctly.

2) Could be a warped front disc. But I would check the brake pads first and see if they need replacing.

3) Yes, looks like the head gasket is leaking. It needs to be replaced.

4) Most likely the o-ring in the tach drive on the cylinder head needs to be replaced.
It's a small o-ring/oil seal; Suzuki Part# 09289-05002.
It's part# 28 in this picture: http://67.15.65.225/spst/1979%20GS750/17.gif .
Check the fiche at http://www.alpha-sports.com/suzuki_parts.htm .

[Anonymous]

On #4, there is both a standard o-ring and an oil seal in the tach housing on the engine. Both should be replaced. Only a few $.

--Tyler

[Anonymous]

Gasket leak and roter thumping from truck fall

I'm looking to get a replacement front rotor for my '81 Suzuki gs550T since it seems to pulsate a whole bunch during stops. From what I know the cycle fell off a moving truck 20 years ago and it rides straight except for breaking. Can someone recommend the size/type of rotor I would need?
Secondly, it seems I have an slow oil leak from the clutch shift lever and was told it might need a new gasket. Is the gasket difficult to replace and is it just a generic item or suzuki specific?

and finally, I've replaced the stock crusier bars with shorter flanders superbike bars which are great but it seems my clutch and throttle cables are too long (my throttle picks revs when i turn the bike to the right cause it gets pushed around alittle), can i just order cables that are an inch or two shorter or should I splice the current cables myself?