no power to ground

[cruiser58]

Noob here, just bought an 81 gs650g, the bike runs but no power to the ground the rear wheel just barely turns while on the center stand as if the clutch is out. Removed the clutch plates and they seem ok. The drive shaft and pumpkin seem solid, with the bike in 1st gear you can turn the clutch basket with your hand and a little resistance can be felt at which time the wheel tries to turn a little. I'm a pretty good backyard mechanic and willing to learn so I guess I'll be splitting the cases and probably trying a rebuild while I'm at it. Just wondering if there is a weak link in the tranny of these bikes which frequently fails so I will have an idea what to look for. I did try the search, but at 3 am I gave up, forgive me. and thanks in advance!

[tom203]

With bike on centerstand, put in first and try to turn rear wheel in forward direction ( I'll assume your clutch is in place)- what happens? Coming out of trans is a set of bevel gears that turn the propeller shaft. On this bike, fifth gear locks the output shaft to input shaft from clutch, so if you can find fifth,see if turning clutch causes rotation of propellor shaft in same amount.

[rustybronco]

The weak link usually is the splined 'hub' in the rear wheel. remove the rear wheel, clean and check the teeth very closely.

looks like this... http://www.thegsresources.com/_forum...43#post1537943

[fishfarm]

I agree the splined hub in the rear wheel should be checked first. Another related link for your reading pleasure:

Always pull the spline hub to inspect

http://www.thegsresources.com/_forum/showthread.php?t=149097

[Nessism]

When you get this sorted out...Honda 60 moly grease is far and away the best (readily available) lubricant for the splines. Do NOT skip the grease, and don't just use regular grease either. The Honda 60 is 60% moly, which is many times more than auto part store "moly" greases.

[Steve]

The easiest way to diagnose is to put the transmission into ANY gear (not sure why fifth was recommended) while the bike is on the centerstand. Squeeze the rubber boot at the swingarm pivot on the left side, you should feel the u-joint in the driveshaft. Try to turn the rear wheel (either direction). If the wheel moves, but the u-joint does not, the splines in the final drive are the likely suspect. If the u-joint moves, it might be the bevel gears at the transmission output.

.

[DanTheMan]

Don't tear it apart any further than you have to. Keep It Simple.....The most common failure is the splines in the rear hub as was stated. If the engine runs good, has low miles, etc., don't start splitting cases and rebuilding things unless you just need more frustration. My bikes both have high mileage and still work well. I've never split the cases on either one yet.

[cruiser58]

Thanx all, it's great to have some experienced brains to pick. When I pulled the clutch plates I removed the plate on the left side and pulled back the shaft boot, I can hold the u joint and turn the clutch basket, I'm betting on the trans output, bevel gears would make sense because at one point in the rotation there is enough teeth left to try to turn the shaft a little. I got the bike right and was hoping for an easy fix, but I'm resigned to a teardown as it is a high mileage bike and I'm sure the engine could use some "freshening up". My first purchase will be a shop manual, any suggestions? Just hoping it doesn't require a garage full of "specialty" tools. Thanks again!

[Steve]

When I pulled the clutch plates I removed the plate on the left side and pulled back the shaft boot, I can hold the u joint and turn the clutch basket, I'm betting on the trans output, bevel gears would make sense because at one point in the rotation there is enough teeth left to try to turn the shaft a little.

Not sure why you started with the clutch plates, but no matter.

Is the transmission IN GEAR while you are trying this?

Actually it really doesn't matter, because if you are moving the basket, I believe that is the input, and is geared to the crank. It is the center shaft that you will need to try to turn to check the output through the transmission. Would have been better to leave everything together to isolate where the problem is, based on the previous suggestions.

I got the bike right and was hoping for an easy fix, but I'm resigned to a teardown as it is a high mileage bike and I'm sure the engine could use some "freshening up".

Please define "high mileage".

There are MANY of us with "experienced" bikes with virtually no problems, in spite of having "high mileage". My wife's bike has about 65,000 miles, which is our highest-mileage GS. Many others on the forum have 100,000 or more miles, so what do YOU consider to be "high mileage"?

My first purchase will be a shop manual, any suggestions? Just hoping it doesn't require a garage full of "specialty" tools. Thanks again!

I see that BassCliff has not seen your post and given you his Mega Welcome. <-- Click that link to read it, then bookmark his "little" website where you can download an official factory service manual.

Unless you have a VERY small garage, it will not be full of the "specialty" tools you will need.

.

[keman]

Most of the manuals are available to download on Bikecliffs site.

As for special tools , get a set of Japanese Phillips drivers. SAE Phillips will round out every screw on the bike.

Valve adjustment shim tool, or zip tie method for adjusting valves.
Access to a vacuume Carb sync tool
Impact driver tool.
Good set of metrics...

[cruiser58]

The po says 56k on the title the bike was running and hitting on all four when I bought it but I haven't run it enough to tell about the condition. I pulled the clutch cos when the engine was running the wheel would turn slowly THROUGH ALL 5 GEARS as if the clutch was fried. My bad for not explaining more clearly but I was turning the INNER part of the clutch basket, the outer is definitely solid with the crank, the slip is definitely between the clutch output and the u joint, I didn't examine the connection between the u joint and the engine closely, but I will, I'm in no hurry to start another labor intensive project right now, plus I haven't found a vendor who lists the bevel gears and I really hate the "junkyard shuffle". Thanks to all who replied and for your patience with the newbie.

[DanTheMan]

but I'm resigned to a teardown as it is a high mileage bike and I'm sure the engine could use some "freshening up". My first purchase will be a shop manual, any suggestions? Just hoping it doesn't require a garage full of "specialty" tools. Thanks again!

Take a look at my sig line. I have never, ever torn down my engine on the 850 past putting a head gasket in due to overheating in the desert.
That 850 now has 97,600mi on it, burns some oil due to bad valve guide seals but still runs strong. It even has the original clutch plates and springs. The 1100G has about 72,000 miles on it, and I quit riding it due to an oil leak on the cam cover that I didn't want to take the time to fix at the end of the riding season, just went back to riding the 850. I don't see full teardowns of either one in the near future at least. That's why I said "Keep it Simple!

[Nessism]

This link may prove useful...http://members.dslextreme.com/users/...pair_zooks.pdf

[cruiser58]

Nessism that link really has my hopes up, I'll be going back to the garage on a rainy night to take a closer look, if the threads are snapped I'll still have to split the cases but if I use the same gears I won't have to set the backlash and tooth contact, right? Thanks, and thanks Keman for the info on the manual downloads, these forums are a blessing for us working stiffs!

[Nessism]

I don't think you have to split the cases to remove the driven secondary gear. When you get to that point please drop Mr. Zooks a PM to pick his brain on the repair.